Multi-criteria Decision Analysis to Model Ixodes ricinus Habitat Suitability.

Science.gov (United States)

Rousseau, Raphaël; McGrath, Guy; McMahon, Barry J; Vanwambeke, Sophie O

2017-09-01

Tick-borne diseases present a major threat to both human and livestock health throughout Europe. The risk of infection is directly related to the presence of its vector. Thereby it is important to know their distribution, which is strongly associated with environmental factors: the presence and availability of a suitable habitat, of a suitable climate and of hosts. The present study models the habitat suitability for Ixodes ricinus in Ireland, where data on tick distribution are scarce. Tick habitat suitability was estimated at a coarse scale (10 km) with a multi-criteria decision analysis (MCDA) method according to four different scenarios (depending on the variables used and on the weights granted to each of them). The western part of Ireland and the Wicklow mountains in the East were estimated to be the most suitable areas for I. ricinus in the island. There was a good level of agreement between results from the MCDA and recorded tick presence. The different scenarios did not affect the spatial outputs substantially. The current study suggests that tick habitat suitability can be mapped accurately at a coarse scale in a data-scarce context using knowledge-based methods. It can serve as a guideline for future countrywide sampling that would help to determine local risk of tick presence and refining knowledge on tick habitat suitability in Ireland.

The areal extent of brown shrimp habitat suitability in Mobile Bay, Alabama, USA: Targeting vegetated habitat restoration

Science.gov (United States)

Smith, L.M.; Nestlerode, J.A.; Harwell, L.C.; Bourgeois, P.

2010-01-01

The availability of wetlands and shallow water habitats significantly influences Gulf of Mexico (GOM) penaeid shrimp fishery productivity. However, the GOM region has the highest rate of wetland loss in the USA. Protection and management of these vital GOM habitats are critical to sustainable shrimp fisheries. Brown shrimp (Farfantepenaeus aztecus) are a major component of GOM fisheries. We present an approach for estimating the areal extent of suitable habitat for post-larval and juvenile brown shrimp in Mobile Bay, Alabama, using an existing habitat suitability index model for the northern GOM calculated from probabilistic survey of water quality and sediment data, land cover data, and submerged aquatic vegetation coverages. This estuarine scale approach is intended to support targeted protection and restoration of these habitats. These analyses indicate that approximately 60% of the area of Mobile Bay is categorized as suitable to near optimal for post-larval and juvenile shrimp and 38% of the area is marginally to minimally suitable. We identify potential units within Mobile Bay for targeted restoration to improve habitat suitability. ?? 2010 Springer Science+Business Media B.V.

Flow Management to Control Excessive Growth of Macrophytes – An Assessment Based on Habitat Suitability Modeling

Science.gov (United States)

Ochs, Konstantin; Rivaes, Rui P.; Ferreira, Teresa; Egger, Gregory

2018-01-01

Mediterranean rivers in intensive agricultural watersheds usually display outgrowths of macrophytes – notably alien species – due to a combination of high concentrations of nutrients in the water runoff and low flows resulting from water abstraction for irrigation. Standard mechanical and chemical control is used to mitigate the problems associated with excessive growth of plant biomass: mainly less drainage capacity and higher flood risk. However, such control measures are cost and labor-intensive and do not present long-term efficiency. Although the high sensitivity of aquatic vegetation to instream hydraulic conditions is well known, management approaches based on flow management remain relatively unexplored. The aim of our study was therefore to apply physical habitat simulation techniques promoted by the Instream Flow Incremental Method (IFIM) to aquatic macrophytes – the first time it has been applied in this context – in order to model shifts in habitat suitability under different flow scenarios in the Sorraia river in central Portugal. We used this approach to test whether the risk of invasion and channel encroachment by nuisance species can be controlled by setting minimum annual flows. We used 960 randomly distributed survey points to analyze the habitat suitability for the most important aquatic species (including the invasive Brazilian milfoil Myriophyllum aquaticum, Sparganium erectum, and Potamogeton crispus) in regard to the physical parameters ‘flow velocity,’ ‘water depth,’ and ‘substrate size’. We chose the lowest discharge period of the year in order to assess the hydraulic conditions while disturbances were at a low-point, thus allowing aquatic vegetation establishment and subsistence. We then used the two-dimensional hydraulic River2D software to model the potential habitat availability for different flow conditions based on the site-specific habitat suitability index for each physical parameter and species. Our results show

Elk habitat suitability map for North Carolina

Science.gov (United States)

Williams, Steven G.; Cobb, David T.; Collazo, Jaime A.

2015-01-01

Although eastern elk (Cervus elaphus canadensis) were extirpated from the eastern United States in the 19th century, they were successfully reintroduced in the North Carolina portion of the Great Smoky Mountains National Park in the early 2000s. The North Carolina Wildlife Resources Commission (NCWRC) is evaluating the prospect of reintroducing the species in other locations in the state to augment recreational opportunities. As a first step in the process, we created a state-wide elk habitat suitability map. We used medium-scale data sets and a two-component approach to iden- tify areas of high biological value for elk and exclude from consideration areas where elk-human conflicts were more likely. Habitats in the state were categorized as 66% unsuitable, 16.7% low, 17% medium, and <1% high suitability for elk. The coastal plain and Piedmont contained the most suitable habitat, but prospective reintroduction sites were largely excluded from consideration due to extensive agricultural activities and pervasiveness of secondary roads. We ranked 31 areas (≥ 500 km2) based on their suitability for reintroduction. The central region of the state contained the top five ranked areas. The Blue Ridge Mountains, where the extant population of elk occurs, was ranked 21st. Our work provides a benchmark for decision makers to evaluate potential consequences and trade-offs associated with the selection of prospective elk reintroduction sites.

Modelling Fish Habitat Suitability in the Eastern English Channel. Application to community habitat level

OpenAIRE

Vaz, Sandrine; Carpentier, Andre; Loots, Christophe; Koubbi, Philippe

2004-01-01

Valuable marine habitats and living resources can be found in the Eastern English Channel and in 2003, a Franco-British Interreg IIIA project, ‘Eastern Channel Habitat Atlas for Marine Resource Management’ (CHARM), was initiated to support decision-making for management of essential fish habitats. Fish habitat corresponds to geographic areas within which ranges of environmental factors define the presence of a particular species. Habitat Suitability index (HSI) modelling was used to relate fi...

Combining dispersal, landscape connectivity and habitat suitability to assess climate-induced changes in the distribution of Cunningham's skink, Egernia cunninghami.

Science.gov (United States)

Ofori, Benjamin Y; Stow, Adam J; Baumgartner, John B; Beaumont, Linda J

2017-01-01

The ability of species to track their climate niche is dependent on their dispersal potential and the connectivity of the landscape matrix linking current and future suitable habitat. However, studies modeling climate-driven range shifts rarely address the movement of species across landscapes realistically, often assuming "unlimited" or "no" dispersal. Here, we incorporate dispersal rate and landscape connectivity with a species distribution model (Maxent) to assess the extent to which the Cunningham's skink (Egernia cunninghami) may be capable of tracking spatial shifts in suitable habitat as climate changes. Our model was projected onto four contrasting, but equally plausible, scenarios describing futures that are (relative to now) hot/wet, warm/dry, hot/with similar precipitation and warm/wet, at six time horizons with decadal intervals (2020-2070) and at two spatial resolutions: 1 km and 250 m. The size of suitable habitat was projected to decline 23-63% at 1 km and 26-64% at 250 m, by 2070. Combining Maxent output with the dispersal rate of the species and connectivity of the intervening landscape matrix showed that most current populations in regions projected to become unsuitable in the medium to long term, will be unable to shift the distance necessary to reach suitable habitat. In particular, numerous populations currently inhabiting the trailing edge of the species' range are highly unlikely to be able to disperse fast enough to track climate change. Unless these populations are capable of adaptation they are likely to be extirpated. We note, however, that the core of the species distribution remains suitable across the broad spectrum of climate scenarios considered. Our findings highlight challenges faced by philopatric species and the importance of adaptation for the persistence of peripheral populations under climate change.

Combining dispersal, landscape connectivity and habitat suitability to assess climate-induced changes in the distribution of Cunningham's skink, Egernia cunninghami.

Directory of Open Access Journals (Sweden)

Benjamin Y Ofori

Full Text Available The ability of species to track their climate niche is dependent on their dispersal potential and the connectivity of the landscape matrix linking current and future suitable habitat. However, studies modeling climate-driven range shifts rarely address the movement of species across landscapes realistically, often assuming "unlimited" or "no" dispersal. Here, we incorporate dispersal rate and landscape connectivity with a species distribution model (Maxent to assess the extent to which the Cunningham's skink (Egernia cunninghami may be capable of tracking spatial shifts in suitable habitat as climate changes. Our model was projected onto four contrasting, but equally plausible, scenarios describing futures that are (relative to now hot/wet, warm/dry, hot/with similar precipitation and warm/wet, at six time horizons with decadal intervals (2020-2070 and at two spatial resolutions: 1 km and 250 m. The size of suitable habitat was projected to decline 23-63% at 1 km and 26-64% at 250 m, by 2070. Combining Maxent output with the dispersal rate of the species and connectivity of the intervening landscape matrix showed that most current populations in regions projected to become unsuitable in the medium to long term, will be unable to shift the distance necessary to reach suitable habitat. In particular, numerous populations currently inhabiting the trailing edge of the species' range are highly unlikely to be able to disperse fast enough to track climate change. Unless these populations are capable of adaptation they are likely to be extirpated. We note, however, that the core of the species distribution remains suitable across the broad spectrum of climate scenarios considered. Our findings highlight challenges faced by philopatric species and the importance of adaptation for the persistence of peripheral populations under climate change.

Developing user-friendly habitat suitability tools from regional stream fish survey data

Science.gov (United States)

Zorn, T.G.; Seelbach, P.; Wiley, M.J.

2011-01-01

We developed user-friendly fish habitat suitability tools (plots) for fishery managers in Michigan; these tools are based on driving habitat variables and fish population estimates for several hundred stream sites throughout the state. We generated contour plots to show patterns in fish biomass for over 60 common species (and for 120 species grouped at the family level) in relation to axes of catchment area and low-flow yield (90% exceedance flow divided by catchment area) and also in relation to axes of mean and weekly range of July temperatures. The plots showed distinct patterns in fish habitat suitability at each level of biological organization studied and were useful for quantitatively comparing river sites. We demonstrate how these plots can be used to support stream management, and we provide examples pertaining to resource assessment, trout stocking, angling regulations, chemical reclamation of marginal trout streams, indicator species, instream flow protection, and habitat restoration. These straightforward and effective tools are electronically available so that managers can easily access and incorporate them into decision protocols and presentations.

Climate and air pollution impacts on habitat suitability of Austrian forest ecosystems.

Science.gov (United States)

Dirnböck, Thomas; Djukic, Ika; Kitzler, Barbara; Kobler, Johannes; Mol-Dijkstra, Janet P; Posch, Max; Reinds, Gert Jan; Schlutow, Angela; Starlinger, Franz; Wamelink, Wieger G W

2017-01-01

Climate change and excess deposition of airborne nitrogen (N) are among the main stressors to floristic biodiversity. One particular concern is the deterioration of valuable habitats such as those protected under the European Habitat Directive. In future, climate-driven shifts (and losses) in the species potential distribution, but also N driven nutrient enrichment may threaten these habitats. We applied a dynamic geochemical soil model (VSD+) together with a novel niche-based plant response model (PROPS) to 5 forest habitat types (18 forest sites) protected under the EU Directive in Austria. We assessed how future climate change and N deposition might affect habitat suitability, defined as the capacity of a site to host its typical plant species. Our evaluation indicates that climate change will be the main driver of a decrease in habitat suitability in the future in Austria. The expected climate change will increase the occurrence of thermophilic plant species while decreasing cold-tolerant species. In addition to these direct impacts, climate change scenarios caused an increase of the occurrence probability of oligotrophic species due to a higher N immobilisation in woody biomass leading to soil N depletion. As a consequence, climate change did offset eutrophication from N deposition, even when no further reduction in N emissions was assumed. Our results show that climate change may have positive side-effects in forest habitats when multiple drivers of change are considered.

Assessing the suitable habitat for reintroduction of brown trout (Salmo trutta forma fario) in a lowland river: A modeling approach.

Science.gov (United States)

Boets, Pieter; Gobeyn, Sacha; Dillen, Alain; Poelman, Eddy; Goethals, Peter L M

2018-05-01

Huge efforts have been made during the past decades to improve the water quality and to restore the physical habitat of rivers and streams in western Europe. This has led to an improvement in biological water quality and an increase in fish stocks in many countries. However, several rheophilic fish species such as brown trout are still categorized as vulnerable in lowland streams in Flanders (Belgium). In order to support cost-efficient restoration programs, habitat suitability modeling can be used. In this study, we developed an ensemble of habitat suitability models using metaheuristic algorithms to explore the importance of a large number of environmental variables, including chemical, physical, and hydromorphological characteristics to determine the suitable habitat for reintroduction of brown trout in the Zwalm River basin (Flanders, Belgium), which is included in the Habitats Directive. Mean stream velocity, water temperature, hiding opportunities, and presence of pools or riffles were identified as the most important variables determining the habitat suitability. Brown trout mainly preferred streams with a relatively high mean reach stream velocity (0.2-1 m/s), a low water temperature (7-15°C), and the presence of pools. The ensemble of models indicated that most of the tributaries and headwaters were suitable for the species. Synthesis and applications . Our results indicate that this modeling approach can be used to support river management, not only for brown trout but also for other species in similar geographical regions. Specifically for the Zwalm River basin, future restoration of the physical habitat, removal of the remaining migration barriers and the development of suitable spawning grounds could promote the successful restoration of brown trout.

Ecological Flow Assessment to Improve the Spawning Habitat for the Four Major Species of Carp of the Yangtze River: A Study on Habitat Suitability Based on Ultrasonic Telemetry

Directory of Open Access Journals (Sweden)

Lixiong Yu

2018-05-01

Full Text Available Four major species of Chinese carp, namely black carp (Mylopharyngodon piceus, grass carp (Ctenopharyngodon idellus, silver carp (Hypophthalmichthys molitrix and bighead carp (Hypophthalmichthys nobilis, are important economic freshwater fish varieties in China. They primarily inhabit and breed in the Yangtze River. Unfortunately, the construction and operation of the Gezhouba Dam and the Three Gorges Dam have dramatically changed the hydrodynamic conditions in the middle reaches of the Yangtze River, leading to a sharp decline in the reproduction rates of these carp. The egg abundance of the four species of carp downstream from the Three Gorges Dam reached 8.35 billion in 1965, but abundance during 2005–2012 was only 0.25 billion. One of the main reasons was that the hydrodynamic conditions of the spawning ground could not meet the four species’ breeding requirements. However, due to the limitations of traditional detection tools, the spawning characteristics of these four species of carp were still unclear. In this study, the ultrasonic telemetry and a three–dimensional hydrodynamic model were utilized to build the habitat suitability index (HSI curves for the four species of carp. The habitat suitability model was then built based on HSI curves to assess spawning habitat quantity under different flow conditions. Finally, the habitat suitability model in the Yidu spawning ground was validated using 32 groups of sampling data in 2015 and 2017. The statistical results showed that the most suitable velocity ranged from 0.78 m/s to 0.93 m/s. The most suitable water depth ranged from 14.56 m to 16.35 m, and the most suitable Froude number ranged from 0.049 to 0.129. The habitat suitability model simulation results indicated that when the discharge was between 15,000 m3/s and 21,300 m3/s, the weighted usable area (WUA values in both the Yidu and Zhicheng spawning grounds would remain at a high level. The validation results showed that most

A habitat suitability model for Pacific oysters (Crassostrea gigas) in the Oosterschelde

NARCIS (Netherlands)

Schellekens, T.; Wijsman, J.W.M.; Brink, van den A.M.

2012-01-01

The modelled habitat suitability maps show a reasonable estimation of the suitability for oysters throughout the Delta and can be used to broadly indicate the consequences of the effect of climate change and infrastructural changes on the habitat suitability for oysters. The largest effect on the

Assessing the Habitat Suitability of Dam Reservoirs: A Quantitative Model and Case Study of the Hantan River Dam, South Korea

Directory of Open Access Journals (Sweden)

Hyeongsik Kang

2016-11-01

Full Text Available The main objective of this study was to investigate ecologically healthy regions near a dam reservoir. This study developed a model for assessing habitat suitability as a proxy for the ecological value of reservoirs. Three main factors comprising nine assessment variables were selected and classified as having a habitat suitability (HS between 0 and 1: (1 geomorphic factors of altitude, slope steepness, and slope aspect; (2 vegetation factors of forest physiognomy, vegetation type, and tree age; and (3 ecological factors of land cover, ecological quality index, and environmental conservation value assessment. The spatial distribution of the nine HS indices was determined using geographic information systems and combined into one HS index value to determine ecologically healthy regions. The assessment model was applied to areas surrounding the Hantan River Dam, South Korea. To verify the model, wildlife location data from the national ecosystem survey of the Ministry of Environment were used. Areas with an HS index between 0.73 and 1 were found to contain 72% of observed wildlife locations. Ecologically healthy areas were identified by adding the indices of each variable. The methods shown here will be useful for establishing ecological restoration plans for dam reservoirs in South Korea.

Climate and air pollution impacts on habitat suitability of Austrian forest ecosystems

Science.gov (United States)

Djukic, Ika; Kitzler, Barbara; Kobler, Johannes; Mol-Dijkstra, Janet P.; Posch, Max; Reinds, Gert Jan; Schlutow, Angela; Starlinger, Franz; Wamelink, Wieger G. W.

2017-01-01

Climate change and excess deposition of airborne nitrogen (N) are among the main stressors to floristic biodiversity. One particular concern is the deterioration of valuable habitats such as those protected under the European Habitat Directive. In future, climate-driven shifts (and losses) in the species potential distribution, but also N driven nutrient enrichment may threaten these habitats. We applied a dynamic geochemical soil model (VSD+) together with a novel niche-based plant response model (PROPS) to 5 forest habitat types (18 forest sites) protected under the EU Directive in Austria. We assessed how future climate change and N deposition might affect habitat suitability, defined as the capacity of a site to host its typical plant species. Our evaluation indicates that climate change will be the main driver of a decrease in habitat suitability in the future in Austria. The expected climate change will increase the occurrence of thermophilic plant species while decreasing cold-tolerant species. In addition to these direct impacts, climate change scenarios caused an increase of the occurrence probability of oligotrophic species due to a higher N immobilisation in woody biomass leading to soil N depletion. As a consequence, climate change did offset eutrophication from N deposition, even when no further reduction in N emissions was assumed. Our results show that climate change may have positive side-effects in forest habitats when multiple drivers of change are considered. PMID:28898262

Climate and air pollution impacts on habitat suitability of Austrian forest ecosystems.

Directory of Open Access Journals (Sweden)

Thomas Dirnböck

Full Text Available Climate change and excess deposition of airborne nitrogen (N are among the main stressors to floristic biodiversity. One particular concern is the deterioration of valuable habitats such as those protected under the European Habitat Directive. In future, climate-driven shifts (and losses in the species potential distribution, but also N driven nutrient enrichment may threaten these habitats. We applied a dynamic geochemical soil model (VSD+ together with a novel niche-based plant response model (PROPS to 5 forest habitat types (18 forest sites protected under the EU Directive in Austria. We assessed how future climate change and N deposition might affect habitat suitability, defined as the capacity of a site to host its typical plant species. Our evaluation indicates that climate change will be the main driver of a decrease in habitat suitability in the future in Austria. The expected climate change will increase the occurrence of thermophilic plant species while decreasing cold-tolerant species. In addition to these direct impacts, climate change scenarios caused an increase of the occurrence probability of oligotrophic species due to a higher N immobilisation in woody biomass leading to soil N depletion. As a consequence, climate change did offset eutrophication from N deposition, even when no further reduction in N emissions was assumed. Our results show that climate change may have positive side-effects in forest habitats when multiple drivers of change are considered.

Combining dispersal, landscape connectivity and habitat suitability to assess climate-induced changes in the distribution of Cunningham’s skink, Egernia cunninghami

Science.gov (United States)

Stow, Adam J.; Baumgartner, John B.; Beaumont, Linda J.

2017-01-01

The ability of species to track their climate niche is dependent on their dispersal potential and the connectivity of the landscape matrix linking current and future suitable habitat. However, studies modeling climate-driven range shifts rarely address the movement of species across landscapes realistically, often assuming “unlimited” or “no” dispersal. Here, we incorporate dispersal rate and landscape connectivity with a species distribution model (Maxent) to assess the extent to which the Cunningham’s skink (Egernia cunninghami) may be capable of tracking spatial shifts in suitable habitat as climate changes. Our model was projected onto four contrasting, but equally plausible, scenarios describing futures that are (relative to now) hot/wet, warm/dry, hot/with similar precipitation and warm/wet, at six time horizons with decadal intervals (2020–2070) and at two spatial resolutions: 1 km and 250 m. The size of suitable habitat was projected to decline 23–63% at 1 km and 26–64% at 250 m, by 2070. Combining Maxent output with the dispersal rate of the species and connectivity of the intervening landscape matrix showed that most current populations in regions projected to become unsuitable in the medium to long term, will be unable to shift the distance necessary to reach suitable habitat. In particular, numerous populations currently inhabiting the trailing edge of the species’ range are highly unlikely to be able to disperse fast enough to track climate change. Unless these populations are capable of adaptation they are likely to be extirpated. We note, however, that the core of the species distribution remains suitable across the broad spectrum of climate scenarios considered. Our findings highlight challenges faced by philopatric species and the importance of adaptation for the persistence of peripheral populations under climate change. PMID:28873398

Quantitative validation of a habitat suitability index for oyster restoration

Directory of Open Access Journals (Sweden)

Seth eTheuerkauf

2016-05-01

Full Text Available Habitat suitability index (HSI models provide spatially explicit information on the capacity of a given habitat to support a species of interest, and their prevalence has increased dramatically in recent years. Despite caution that the reliability of HSIs must be validated using independent, quantitative data, most HSIs intended to inform terrestrial and marine species management remain unvalidated. Furthermore, of the eight HSI models developed for eastern oyster (Crassostrea virginica restoration and fishery production, none has been validated. Consequently, we developed, calibrated, and validated an HSI for the eastern oyster to identify optimal habitat for restoration in a tributary of Chesapeake Bay, the Great Wicomico River (GWR. The GWR harbors a high density, restored oyster population, and therefore serves as an excellent model system for assessing the validity of the HSI. The HSI was derived from GIS layers of bottom type, salinity, and water depth (surrogate for dissolved oxygen, and was tested using live adult oyster density data from a survey of high vertical relief reefs (HRR and low vertical relief reefs (LRR in the sanctuary network. Live adult oyster density was a statistically-significant sigmoid function of the HSI, which validates the HSI as a robust predictor of suitable oyster reef habitat for rehabilitation or restoration. In addition, HRR had on average 103-116 more adults m^−2 than LRR at a given level of the HSI. For HRR, HSI values ≥0.3 exceeded the accepted restoration target of 50 live adult oysters m^−2. For LRR, the HSI was generally able to predict live adult oyster densities that meet or exceed the target at HSI values ≥0.3. The HSI indicated that there remain large areas of suitable habitat for restoration in the GWR. This study provides a robust framework for HSI model development and validation, which can be refined and applied to other systems and previously developed HSIs to improve the efficacy of

A habitat suitability model for Chinese sturgeon determined using the generalized additive method

Science.gov (United States)

Yi, Yujun; Sun, Jie; Zhang, Shanghong

2016-03-01

The Chinese sturgeon is a type of large anadromous fish that migrates between the ocean and rivers. Because of the construction of dams, this sturgeon's migration path has been cut off, and this species currently is on the verge of extinction. Simulating suitable environmental conditions for spawning followed by repairing or rebuilding its spawning grounds are effective ways to protect this species. Various habitat suitability models based on expert knowledge have been used to evaluate the suitability of spawning habitat. In this study, a two-dimensional hydraulic simulation is used to inform a habitat suitability model based on the generalized additive method (GAM). The GAM is based on real data. The values of water depth and velocity are calculated first via the hydrodynamic model and later applied in the GAM. The final habitat suitability model is validated using the catch per unit effort (CPUEd) data of 1999 and 2003. The model results show that a velocity of 1.06-1.56 m/s and a depth of 13.33-20.33 m are highly suitable ranges for the Chinese sturgeon to spawn. The hydraulic habitat suitability indexes (HHSI) for seven discharges (4000; 9000; 12,000; 16,000; 20,000; 30,000; and 40,000 m3/s) are calculated to evaluate integrated habitat suitability. The results show that the integrated habitat suitability reaches its highest value at a discharge of 16,000 m3/s. This study is the first to apply a GAM to evaluate the suitability of spawning grounds for the Chinese sturgeon. The study provides a reference for the identification of potential spawning grounds in the entire basin.

A test of the habitat suitability model for Merriam's wild turkeys

Science.gov (United States)

Mark A. Rumble; Stanley H. Anderson

1996-01-01

An important research area regarding the wild turkey (Meleagris gallopavo) is development of sound habitat models. Habitat models provide standardized methods to quantify wild turkey habitat and stimulate new research hypotheses. Habitat suitability index (HSI) models show species-habitat relationships on a scale of O-l, with 1 being optimum. A...

High-resolution assessment of land use impacts on biodiversity in life cycle assessment using species habitat suitability models.

Science.gov (United States)

de Baan, Laura; Curran, Michael; Rondinini, Carlo; Visconti, Piero; Hellweg, Stefanie; Koellner, Thomas

2015-02-17

Agricultural land use is a main driver of global biodiversity loss. The assessment of land use impacts in decision-support tools such as life cycle assessment (LCA) requires spatially explicit models, but existing approaches are either not spatially differentiated or modeled at very coarse scales (e.g., biomes or ecoregions). In this paper, we develop a high-resolution (900 m) assessment method for land use impacts on biodiversity based on habitat suitability models (HSM) of mammal species. This method considers potential land use effects on individual species, and impacts are weighted by the species' conservation status and global rarity. We illustrate the method using a case study of crop production in East Africa, but the underlying HSMs developed by the Global Mammals Assessment are available globally. We calculate impacts of three major export crops and compare the results to two previously developed methods (focusing on local and regional impacts, respectively) to assess the relevance of the methodological innovations proposed in this paper. The results highlight hotspots of product-related biodiversity impacts that help characterize the links among agricultural production, consumption, and biodiversity loss.

Mapping anuran habitat suitability to estimate effects of grassland and wetland conservation programs

Science.gov (United States)

Mushet, David M.; Euliss, Ned H.; Stockwell, Craig A.

2012-01-01

The conversion of the Northern Great Plains of North America to a landscape favoring agricultural commodity production has negatively impacted wildlife habitats. To offset impacts, conservation programs have been implemented by the U.S. Department of Agriculture and other agencies to restore grassland and wetland habitat components. To evaluate effects of these efforts on anuran habitats, we used call survey data and environmental data in ecological niche factor analyses implemented through the program Biomapper to quantify habitat suitability for five anuran species within a 196 km2 study area. Our amphibian call surveys identified Northern Leopard Frogs (Lithobates pipiens), Wood Frogs (Lithobates sylvaticus), Boreal Chorus Frogs (Pseudacris maculata), Great Plains Toads (Anaxyrus cognatus), and Woodhouse’s Toads (Anaxyrus woodhousii) occurring within the study area. Habitat suitability maps developed for each species revealed differing patterns of suitable habitat among species. The most significant findings of our mapping effort were 1) the influence of deep-water overwintering wetlands on suitable habitat for all species encountered except the Boreal Chorus Frog; 2) the lack of overlap between areas of core habitat for both the Northern Leopard Frog and Wood Frog compared to the core habitat for both toad species; and 3) the importance of conservation programs in providing grassland components of Northern Leopard Frog and Wood Frog habitat. The differences in habitats suitable for the five species we studied in the Northern Great Plains, i.e., their ecological niches, highlight the importance of utilizing an ecosystem based approach that considers the varying needs of multiple species in the development of amphibian conservation and management plans.

Habitat suitability and nest survival of white-headed woodpeckers in unburned forests of Oregon

Science.gov (United States)

Hollenbeck, Jeff P.; Saab, Victoria A.; Frenzel, Richard W.

2011-01-01

We evaluated habitat suitability and nest survival of breeding white-headed woodpeckers (Picoides albolarvatus) in unburned forests of central Oregon, USA. Daily nest-survival rate was positively related to maximum daily temperature during the nest interval and to density of large-diameter trees surrounding the nest tree. We developed a niche-based habitat suitability model (partitioned Mahalanobis distance) for nesting white-headed woodpeckers using remotely sensed data. Along with low elevation, high density of large trees, and low slope, our habitat suitability model suggested that interspersion–juxtaposition of low- and high-canopy cover ponderosa pine (Pinus ponderosa) patches was important for nest-site suitability. Cross-validation suggested the model performed adequately for management planning at a scale >1 ha. Evaluation of mapped habitat suitability index (HSI) suggested that the maximum predictive gain (HSI = 0.36), where the number of nest locations are maximized in the smallest proportion of the modeled landscape, provided an objective initial threshold for identification of suitable habitat. However, managers can choose the threshold HSI most appropriate for their purposes (e.g., locating regions of low–moderate suitability that have potential for habitat restoration). Consequently, our habitat suitability model may be useful for managing dry coniferous forests for white-headed woodpeckers in central Oregon; however, model validation is necessary before our model could be applied to other locations.

Using urban forest assessment tools to model bird habitat potential

Science.gov (United States)

Lerman, Susannah B.; Nislow, Keith H.; Nowak, David J.; DeStefano, Stephen; King, David I.; Jones-Farrand, D. Todd

2014-01-01

The alteration of forest cover and the replacement of native vegetation with buildings, roads, exotic vegetation, and other urban features pose one of the greatest threats to global biodiversity. As more land becomes slated for urban development, identifying effective urban forest wildlife management tools becomes paramount to ensure the urban forest provides habitat to sustain bird and other wildlife populations. The primary goal of this study was to integrate wildlife suitability indices to an existing national urban forest assessment tool, i-Tree. We quantified available habitat characteristics of urban forests for ten northeastern U.S. cities, and summarized bird habitat relationships from the literature in terms of variables that were represented in the i-Tree datasets. With these data, we generated habitat suitability equations for nine bird species representing a range of life history traits and conservation status that predicts the habitat suitability based on i-Tree data. We applied these equations to the urban forest datasets to calculate the overall habitat suitability for each city and the habitat suitability for different types of land-use (e.g., residential, commercial, parkland) for each bird species. The proposed habitat models will help guide wildlife managers, urban planners, and landscape designers who require specific information such as desirable habitat conditions within an urban management project to help improve the suitability of urban forests for birds.

Habitat suitability and movement corridors of grey wolf (Canis lupus) in Northern Pakistan

Science.gov (United States)

Kabir, Muhammad; Hameed, Shoaib; Ali, Hussain; Bosso, Luciano; Din, Jaffar Ud; Bischof, Richard; Redpath, Steve

2017-01-01

Habitat suitability models are useful to understand species distribution and to guide management and conservation strategies. The grey wolf (Canis lupus) has been extirpated from most of its historic range in Pakistan primarily due to its impact on livestock and livelihoods. We used non-invasive survey data from camera traps and genetic sampling to develop a habitat suitability model for C. lupus in northern Pakistan and to explore the extent of connectivity among populations. We detected suitable habitat of grey wolf using a maximum entropy approach (Maxent ver. 3.4.0) and identified suitable movement corridors using the Circuitscape 4.0 tool. Our model showed high levels of predictive performances, as seen from the values of area under curve (0.971±0.002) and true skill statistics (0.886±0.021). The main predictors for habitat suitability for C. lupus were distances to road, mean temperature of the wettest quarter and distance to river. The model predicted ca. 23,129 km2 of suitable areas for wolf in Pakistan, with much of suitable habitat in remote and inaccessible areas that appeared to be well connected through vulnerable movement corridors. These movement corridors suggest that potentially the wolf range can expand in Pakistan’s Northern Areas. However, managing protected areas with stringent restrictions is challenging in northern Pakistan, in part due to heavy dependence of people on natural resources. The habitat suitability map provided by this study can inform future management strategies by helping authorities to identify key conservation areas. PMID:29121089

Comparing habitat suitability and connectivity modeling methods for conserving pronghorn migrations.

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Erin E Poor

Full Text Available Terrestrial long-distance migrations are declining globally: in North America, nearly 75% have been lost. Yet there has been limited research comparing habitat suitability and connectivity models to identify migration corridors across increasingly fragmented landscapes. Here we use pronghorn (Antilocapra americana migrations in prairie habitat to compare two types of models that identify habitat suitability: maximum entropy (Maxent and expert-based (Analytic Hierarchy Process. We used distance to wells, distance to water, NDVI, land cover, distance to roads, terrain shape and fence presence to parameterize the models. We then used the output of these models as cost surfaces to compare two common connectivity models, least-cost modeling (LCM and circuit theory. Using pronghorn movement data from spring and fall migrations, we identified potential migration corridors by combining each habitat suitability model with each connectivity model. The best performing model combination was Maxent with LCM corridors across both seasons. Maxent out-performed expert-based habitat suitability models for both spring and fall migrations. However, expert-based corridors can perform relatively well and are a cost-effective alternative if species location data are unavailable. Corridors created using LCM out-performed circuit theory, as measured by the number of pronghorn GPS locations present within the corridors. We suggest the use of a tiered approach using different corridor widths for prioritizing conservation and mitigation actions, such as fence removal or conservation easements.

Comparing habitat suitability and connectivity modeling methods for conserving pronghorn migrations.

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Poor, Erin E; Loucks, Colby; Jakes, Andrew; Urban, Dean L

2012-01-01

Terrestrial long-distance migrations are declining globally: in North America, nearly 75% have been lost. Yet there has been limited research comparing habitat suitability and connectivity models to identify migration corridors across increasingly fragmented landscapes. Here we use pronghorn (Antilocapra americana) migrations in prairie habitat to compare two types of models that identify habitat suitability: maximum entropy (Maxent) and expert-based (Analytic Hierarchy Process). We used distance to wells, distance to water, NDVI, land cover, distance to roads, terrain shape and fence presence to parameterize the models. We then used the output of these models as cost surfaces to compare two common connectivity models, least-cost modeling (LCM) and circuit theory. Using pronghorn movement data from spring and fall migrations, we identified potential migration corridors by combining each habitat suitability model with each connectivity model. The best performing model combination was Maxent with LCM corridors across both seasons. Maxent out-performed expert-based habitat suitability models for both spring and fall migrations. However, expert-based corridors can perform relatively well and are a cost-effective alternative if species location data are unavailable. Corridors created using LCM out-performed circuit theory, as measured by the number of pronghorn GPS locations present within the corridors. We suggest the use of a tiered approach using different corridor widths for prioritizing conservation and mitigation actions, such as fence removal or conservation easements.

Transferability of habitat suitability criteria for fishes in warmwater streams

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Freeman, Mary C.; Bowen, Z.H.; Crance, J.H.

1997-01-01

We developed habitat suitability criteria and tested their transferability for nine fishes inhabiting unregulated Piedmont and Coastal Plain streams in Alabama. Cr iteria for optimal habitat were defined as ranges of depth, velocity, substrate type and cover type for which a species' suitability index (proportional abundance divided by proportional habitat availability, scaled from 0 to 1) equalled or exceeded 0.4. We evaluated the transferability of criteria between study sites by testing the null hypothesis that species occurrence in a sample was independent of whether or not the sample was taken in optimal habitat. We also tested criteria transference to a large, flow-regulated river sampled during low flow periods. Depth, velocity and most substrate criteria developed for the bronze darter Percina palmaris successfully transferred between unregulated streams and to the flow-regulated river samples. All criteria developed for a pair of closely related, allopatric darter species, Etheostoma chuckwachattee and E. jordani, transferred sucessfully when applied between species (in the unregulated sites) and to the regulated river samples. In contrast, criteria for the Alabama shiner Cyprinella callistia failed nearly all tests of transferability. Criteria for E. stigmaeum, P. nigrofasciata, an undescribed Percina species, and a pair of related, allopatric Cyprinella species transferred inconsistently. The species with good criteria transference had high suitability indices for shallow depths, fast current velocities and coarse substrates, characteristic of riffle species. We suggest that microhabitat criteria for riffle fishes are more likely to provide a transferable measure of habitat quality than criteria for fishes that, although restricted to fluvial habitats, commonly occupy a variety of pool and riffle habitats.

Modelling seasonal habitat suitability for wide-ranging species: Invasive wild pigs in northern Australia.

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Jens G Froese

Full Text Available Invasive wildlife often causes serious damage to the economy and agriculture as well as environmental, human and animal health. Habitat models can fill knowledge gaps about species distributions and assist planning to mitigate impacts. Yet, model accuracy and utility may be compromised by small study areas and limited integration of species ecology or temporal variability. Here we modelled seasonal habitat suitability for wild pigs, a widespread and harmful invader, in northern Australia. We developed a resource-based, spatially-explicit and regional-scale approach using Bayesian networks and spatial pattern suitability analysis. We integrated important ecological factors such as variability in environmental conditions, breeding requirements and home range movements. The habitat model was parameterized during a structured, iterative expert elicitation process and applied to a wet season and a dry season scenario. Model performance and uncertainty was evaluated against independent distributional data sets. Validation results showed that an expert-averaged model accurately predicted empirical wild pig presences in northern Australia for both seasonal scenarios. Model uncertainty was largely associated with different expert assumptions about wild pigs' resource-seeking home range movements. Habitat suitability varied considerably between seasons, retracting to resource-abundant rainforest, wetland and agricultural refuge areas during the dry season and expanding widely into surrounding grassland floodplains, savanna woodlands and coastal shrubs during the wet season. Overall, our model suggested that suitable wild pig habitat is less widely available in northern Australia than previously thought. Mapped results may be used to quantify impacts, assess risks, justify management investments and target control activities. Our methods are applicable to other wide-ranging species, especially in data-poor situations.

Managing Environmental Flows for Impounded Rivers in Semi-Arid Regions- A Habitat Suitability Index (HSI) Approach for the Assessment of River Habitat for Salmonid Populations

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Pai, H.; Sivakumaran, K.; Villamizar, S. R.; Flanagan, J.; Guo, Q.; Harmon, T. C.

2013-12-01

Balancing ecosystem health in water-scarce, agriculturally dominated river basins remains a challenge. In dry water years, maintaining conditions for restored and sustained indigenous fish populations (a frequently used indicator for ecosystem health) is particularly challenging. Competing human demands include urban and agricultural water supplies, hydropower, and flood control. In many semi-arid regions, increasing drought intensity and frequency under future climate scenarios will combine with population increases to water scarcity. The goal of this work is to better understand how reservoir releases affect fish habitat and overall river aquatic ecosystem quality. Models integrating a diverse array of physical and biological processes and system state are used to forecast the river ecosystem response to changing drivers. We propose a distributed parameter-based Habitat Suitability Index (HSI) approach for assessing fish habitat quality. Our river ecosystem HSI maps are based on a combination of the following: (1) In situ data describing stream flow and water quality conditions; (2) Spatial observations, including surveyed cross-sections, aerial imagery and digital elevation maps (DEM) of the river and its riparian corridor; and (3) Simulated spatially distributed water depths, flow velocities, and temperatures estimated from 1D and 2D river flow and temperature models (HEC-RAS and CE-QUAL-W2, respectively). With respect to (2), image processing schemes are used to classify and map key habitat features, namely riparian edge and shallow underwater vegetation. HSI maps can be modified temporally to address specific life cycle requirements of indicator fish species. Results are presented for several reaches associated with the San Joaquin River Restoration Project, focusing on several components of the Chinook salmon life cycle. HSI maps and interpretations are presented in the context of a range of prescribed reservoir release hydrographs linked to California water

Ecological variables governing habitat suitability and the distribution ...

African Journals Online (AJOL)

governed by soil particle size distribution), in combination with the cover provided by trees, as the two ecological factors that best explained habitat suitability for Juliana's golden mole at the three localities. An IndVal analysis failed to identify ...

A Bayesian spawning habitat suitability model for American shad in southeastern United States rivers

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Hightower, Joseph E.; Harris, Julianne E.; Raabe, Joshua K.; Brownell, Prescott; Drew, C. Ashton

2012-01-01

Habitat suitability index models for American shad Alosa sapidissima were developed by Stier and Crance in 1985. These models, which were based on a combination of published information and expert opinion, are often used to make decisions about hydropower dam operations and fish passage. The purpose of this study was to develop updated habitat suitability index models for spawning American shad in the southeastern United States, building on the many field and laboratory studies completed since 1985. We surveyed biologists who had knowledge about American shad spawning grounds, assembled a panel of experts to discuss important habitat variables, and used raw data from published and unpublished studies to develop new habitat suitability curves. The updated curves are based on resource selection functions, which can model habitat selectivity based on use and availability of particular habitats. Using field data collected in eight rivers from Virginia to Florida (Mattaponi, Pamunkey, Roanoke, Tar, Neuse, Cape Fear, Pee Dee, St. Johns), we obtained new curves for temperature, current velocity, and depth that were generally similar to the original models. Our new suitability function for substrate was also similar to the original pattern, except that sand (optimal in the original model) has a very low estimated suitability. The Bayesian approach that we used to develop habitat suitability curves provides an objective framework for updating the model as new studies are completed and for testing the model's applicability in other parts of the species' range.

Himalayan ibex (Capra ibex sibirica habitat suitability and range resource dynamics in the Central Karakorum National Park, Pakistan

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Garee Khan

2016-07-01

Full Text Available The study investigates Himalayan ibex (Capra ibex sibirica and their range resource condition within the preferred habitat in the Central Karakoram National Park, Pakistan. We apply ecological niche factor analysis (ENFA using 110 ibex sighting data and 6 key biophysical variables describing the habitat conditions and produce habitat suitability and maps with GIS and statistical tool (BioMapper. The modeling results of specialization factor shows some limitation for ibex over the use of slope, elevation, vegetation types and ruggedness. The habitat area selection for the ibex is adjusted to the ibex friendly habitat available conditions. The model results predicted suitable habitat for ibex in certain places, where field observation was never recorded. The range resource dynamics depict a large area that comes under the alpine meadows has the highest seasonal productivity, assessed by remote sensing based fortnightly vegetation condition data of the last 11 years. These meadows are showing browning trend over the years, attributable to grazing practices or climate conditions. At lower elevation, there are limited areas with suitable dry steppes, which may cause stress on ibex, especially during winter.

Influence of discharge on fish habitat suitability curves in mountain watercourses in IFIM methodology

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Macura Viliam

2018-03-01

Full Text Available In this study, the quality of the aquatic habitats of mountain and piedmont streams was evaluated using the ‘Instream Flow Incremental Methodology (IFIM’ decision-making tool. The quality of habitats was interpreted from the behaviour of bioindicators in the form of habitat suitability curves (HSCs. From 1995 until the present, 59 different reaches of 43 mountain streams in Slovakia and 3 validation reaches were evaluated, and the results analysed. The aim of this study was to generalize the parameters of the HSCs for the brown trout. The generalized curves will be useful for water management planning. It is difficult and time-consuming to take hydrometrical and ichthyological measurements at different water levels. Therefore, we developed a methodology for modifying suitability curves based on an ichthyological survey during a low flow and a flow at which fish lose the ability to resist the flow velocity. The study provides the information how such curves can be modified for a wider flow range. In summary, this study shows that generalized HSCs provide representative data that can be used to support both the design of river restoration and the assessment of the impacts of the water use or of climate change on stream habitat quality.

Multiscale habitat suitability index models for priority landbirds in the Central Hardwoods and West Gulf Coastal Plain/Ouachitas Bird Conservation Regions

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John M. Tirpak; D. Todd Jones-Farrand; Frank R., III Thompson; Daniel J. Twedt; William B., III Uihlein

2009-01-01

Habitat Suitability Index (HSI) models were developed to assess habitat quality for 40 priority bird species in the Central Hardwoods and West Gulf Coastal Plain/Ouachitas Bird Conservation Regions. The models incorporated both site and landscape environmental variables from one of six nationally consistent datasets. Potential habitat was first defined from unique...

Habitat Suitability analysis of Koklass (Pucrasia macrolopha) Pheasant in Churdhar Wildlife Sanctuary of Himachal Pradesh, India using Geospatial Technology

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Eliza, K.; Sarma, K.

2014-12-01

Pheasants are at the brink of destruction due to degradation of forests, environmental pollution, climatic changes and extensive hunting of wild floras and faunas.The problem is more acute in the developing countries where wildlife and biodiversity conservation are often less prioritized due to more pressing demands of food security and poverty alleviation. Koklass Pheasant (Pucrasia macrolopha) species is distributed from Afghanistan and Pakistan in the east along the Himalayas to southeastern Tibet, western China and southeastern Mongolia.This species is grouped under endangered species in Red Data Book of Zoological Survey of India and also classified as least concern species according to IUCN Red List of Threatened Species.Conservation biologists and managers need a range of both classical analyses and specific modern tools to face the increasing threats to biodiversity. Among these tools, habitat-suitability modeling has recently emerged as a relevant technique to assess global impacts to define wide conservation priorities.The present study is carried out using remote sensing satellite imagery and GIS modeling technique for assessing habitat suitability of Koklass Pheasants and finding out the habitat factors influencing the Koklass distribution in Churdhar Wildlife Sanctuary, India. Effective management and conservation of wildlife populations and their habitats largely depend on our ability to understand and predict species-habitat interactions. Different thematic maps viz., land use/cover, forest types, drainage buffer, multiple ring buffers of sighting locations and multiple ring buffers of roads have been prepared to support the objective of the study. The Weighted Overlay Analysis model is used for identifying different potential areas of habitat for this endangered species. The most suitable area for Koklass Pheasant within the Wildlife Sanctuary is found to be about 23.8 percent of the total area which is due to favourable habitat conditions for the

High Resolution Habitat Suitability Modelling For Restricted-Range Hawaiian Alpine Arthropod Species

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Stephenson, N. M.

2016-12-01

Mapping potentially suitable habitat is critical for effective species conservation and management but can be challenging in areas exhibiting complex heterogeneity. An approach that combines non-intrusive spatial data collection techniques and field data can lead to a better understanding of landscapes and species distributions. Nysius wekiuicola, commonly known as the wēkiu bug, is the most studied arthropod species endemic to the Maunakea summit in Hawai`i, yet details about its geographic distribution and habitat use remain poorly understood. To predict the geographic distribution of N. wekiuicola, MaxEnt habitat suitability models were generated from a diverse set of input variables, including fifteen years of species occurrence data, high resolution digital elevation models, surface mineralogy maps derived from hyperspectral remote sensing, and climate data. Model results indicate that elevation (78.2 percent), and the presence of nanocrystalline hematite surface minerals (13.7 percent) had the highest influence, with lesser contributions from aspect, slope, and other surface mineral classes. Climatic variables were not included in the final analysis due to auto-correlation and coarse spatial resolution. Biotic factors relating to predation and competition also likely dictate wēkiu bug capture patterns and influence our results. The wēkiu bug range and habitat suitability models generated as a result of this study will be directly incorporated into management and restoration goals for the summit region and can also be adapted for other arthropod species present, leading to a more holistic understanding of metacommunity dynamics. Key words: Microhabitat, Structure from Motion, Lidar, MaxEnt, Habitat Suitability

Habitat suitability modeling for the endangered Hawaiian petrel on Kauai and analysis of predicted habitat overlap with the Newell’s shearwater

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Jeff R. Troy

2017-10-01

Full Text Available The endangered Hawaiian petrel (Pterodroma sandwichensis is endemic to the main Hawaiian Islands and has undergone a breeding range contraction since the arrival of humans. Using abiotic and biotic environmental variables, we developed a terrestrial habitat suitability model for the species on the island of Kauai based on contemporary sites where the species is known (or strongly suspected to nest, as well as a habitat/threat-isolation index that combined predictions from this suitability model with spatial information on two anthropogenic threats to the species. After accounting for large-scale relative spatial positioning of sites in modeling procedures, the habitat suitability model suggests that the probability that a location on Kauai could be suitable for Hawaiian petrel nesting activity increases with increasing mean annual wind speed, and may also increase somewhat with increasing slope and native vegetation cover. The habitat suitability model (which does not incorporate spatial information on anthropogenic threats to the species predicts approximately 74 km2 of Kauai, mostly in the interior of the island, as being potentially suitable with predicted probability > 0.7 for Hawaiian petrel terrestrial activity, and about 35 km2 with predicted probability > 0.9. Encouragingly, almost 50 km2 of land with predicted probability > 0.7 and almost 24 km2 with predicted probability > 0.9 is currently protected, being located on either government or private reserve land. Based on the habitat/threat-isolation index, most land predicted to be both suitable (based on environmental variables and as isolated from threats as a large number of the known contemporary Hawaiian petrel sites, is found in government and private reserves. Some degree of predicted habitat overlap between the Hawaiian petrel and Newell’s shearwater (Puffinus newelli, another Hawaiian seabird of conservation concern, suggests that some of the same larger tracts of land

A comparative framework to infer landscape effects on population genetic structure: Are habitat suitability models effective in explaining gene flow?

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Maria C. Mateo-Sanchez; Niko Balkenhol; Samuel Cushman; Trinidad Perez; Ana Dominguez; Santiago Saura

2015-01-01

Most current methods to assess connectivity begin with landscape resistance maps. The prevailing resistance models are commonly based on expert opinion and, more recently, on a direct transformation of habitat suitability. However, habitat associations are not necessarily accurate indicators of dispersal, and thus may fail as a surrogate of resistance to...

Development of habitat suitability criteria for Neotropical stream fishes and an assessment of their transferability to streams with different conservation status

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Fabrício Barreto Teresa

Full Text Available We assessed the preference of 10 fish species for depth and velocity conditions in forested streams from southeastern Brazil using habitat suitability criteria (HSC curves. We also tested whether preference patterns observed in forested streams can be transferred to deforested streams. We used data from fish sampled in 62 five-meter sites in three forested streams to construct preference curves. Astyanax altiparanae, A. fasciatus, Knodus moenkhausii, and Piabina argentea showed a preference for deep slow habitats, whereas Aspidoras fuscoguttatus, Characidium zebra, Cetopsorhamdia iheringi, Pseudopimelodus pulcher, and Hypostomus nigromaculatus showed an opposite pattern: preference for shallow fast habitats. Hypostomus ancistroides showed a multimodal pattern of preference for depth and velocity. To evaluate whether patterns observed in forested streams may be transferred to deforested streams, we sampled 64 five-meters sites in three deforested streams using the same methodology. The preference for velocity was more consistent than for depth, as success in the transferability criterion was 86% and 29% of species, respectively. This indicates that velocity is a good predictor of species abundance in streams, regardless of their condition

Silvicolous on a small scale: possibilities and limitations of habitat suitability models for small, elusive mammals in conservation management and landscape planning.

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Becker, Nina I; Encarnação, Jorge A

2015-01-01

Species distribution and endangerment can be assessed by habitat-suitability modelling. This study addresses methodical aspects of habitat suitability modelling and includes an application example in actual species conservation and landscape planning. Models using species presence-absence data are preferable to presence-only models. In contrast to species presence data, absences are rarely recorded. Therefore, many studies generate pseudo-absence data for modelling. However, in this study model quality was higher with null samples collected in the field. Next to species data the choice of landscape data is crucial for suitability modelling. Landscape data with high resolution and ecological relevance for the study species improve model reliability and quality for small elusive mammals like Muscardinus avellanarius. For large scale assessment of species distribution, models with low-detailed data are sufficient. For regional site-specific conservation issues like a conflict-free site for new wind turbines, high-detailed regional models are needed. Even though the overlap with optimally suitable habitat for M. avellanarius was low, the installation of wind plants can pose a threat due to habitat loss and fragmentation. To conclude, modellers should clearly state the purpose of their models and choose the according level of detail for species and environmental data.

Spatial Heterogeneity of Habitat Suitability for Rift Valley Fever Occurrence in Tanzania: An Ecological Niche Modelling Approach

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Sindato, Calvin; Stevens, Kim B.; Karimuribo, Esron D.; Mboera, Leonard E. G.; Paweska, Janusz T.; Pfeiffer, Dirk U.

2016-01-01

Background Despite the long history of Rift Valley fever (RVF) in Tanzania, extent of its suitable habitat in the country remains unclear. In this study we investigated potential effects of temperature, precipitation, elevation, soil type, livestock density, rainfall pattern, proximity to wild animals, protected areas and forest on the habitat suitability for RVF occurrence in Tanzania. Materials and Methods Presence-only records of 193 RVF outbreak locations from 1930 to 2007 together with potential predictor variables were used to model and map the suitable habitats for RVF occurrence using ecological niche modelling. Ground-truthing of the model outputs was conducted by comparing the levels of RVF virus specific antibodies in cattle, sheep and goats sampled from locations in Tanzania that presented different predicted habitat suitability values. Principal Findings Habitat suitability values for RVF occurrence were higher in the northern and central-eastern regions of Tanzania than the rest of the regions in the country. Soil type and precipitation of the wettest quarter contributed equally to habitat suitability (32.4% each), followed by livestock density (25.9%) and rainfall pattern (9.3%). Ground-truthing of model outputs revealed that the odds of an animal being seropositive for RVFV when sampled from areas predicted to be most suitable for RVF occurrence were twice the odds of an animal sampled from areas least suitable for RVF occurrence (95% CI: 1.43, 2.76, p < 0.001). Conclusion/Significance The regions in the northern and central-eastern Tanzania were more suitable for RVF occurrence than the rest of the regions in the country. The modelled suitable habitat is characterised by impermeable soils, moderate precipitation in the wettest quarter, high livestock density and a bimodal rainfall pattern. The findings of this study should provide guidance for the design of appropriate RVF surveillance, prevention and control strategies which target areas with

Development of tiger habitat suitability model using geospatial tools-a case study in Achankmar Wildlife Sanctuary (AMWLS), Chhattisgarh India.

Science.gov (United States)

Singh, R; Joshi, P K; Kumar, M; Dash, P P; Joshi, B D

2009-08-01

Geospatial tools supported by ancillary geo-database and extensive fieldwork regarding the distribution of tiger and its prey in Anchankmar Wildlife Sanctuary (AMWLS) were used to build a tiger habitat suitability model. This consists of a quantitative geographical information system (GIS) based approach using field parameters and spatial thematic information. The estimates of tiger sightings, its prey sighting and predicted distribution with the assistance of contextual environmental data including terrain, road network, settlement and drainage surfaces were used to develop the model. Eight variables in the dataset viz., forest cover type, forest cover density, slope, aspect, altitude, and distance from road, settlement and drainage were seen as suitable proxies and were used as independent variables in the analysis. Principal component analysis and binomial multiple logistic regression were used for statistical treatments of collected habitat parameters from field and independent variables respectively. The assessment showed a strong expert agreement between the predicted and observed suitable areas. A combination of the generated information and published literature was also used while building a habitat suitability map for the tiger. The modeling approach has taken the habitat preference parameters of the tiger and potential distribution of prey species into account. For assessing the potential distribution of prey species, independent suitability models were developed and validated with the ground truth. It is envisaged that inclusion of the prey distribution probability strengthens the model when a key species is under question. The results of the analysis indicate that tiger occur throughout the sanctuary. The results have been found to be an important input as baseline information for population modeling and natural resource management in the wildlife sanctuary. The development and application of similar models can help in better management of the protected

Ensemble modeling to predict habitat suitability for a large-scale disturbance specialist

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Quresh S. Latif; Victoria A. Saab; Jonathan G. Dudley; Jeff P. Hollenbeck

2013-01-01

To conserve habitat for disturbance specialist species, ecologists must identify where individuals will likely settle in newly disturbed areas. Habitat suitability models can predict which sites at new disturbances will most likely attract specialists. Without validation data from newly disturbed areas, however, the best approach for maximizing predictive accuracy can...

Modeling mountain pine beetle habitat suitability within Sequoia National Park

Science.gov (United States)

Nguyen, Andrew

Understanding significant changes in climate and their effects on timber resources can help forest managers make better decisions regarding the preservation of natural resources and land management. These changes may to alter natural ecosystems dependent on historical and current climate conditions. Increasing mountain pine beetle (MBP) outbreaks within the southern Sierra Nevada are the result of these alterations. This study better understands MPB behavior within Sequoia National Park (SNP) and model its current and future habitat distribution. Variables contributing to MPB spread are vegetation stress, soil moisture, temperature, precipitation, disturbance, and presence of Ponderosa (Pinus ponderosa) and Lodgepole (Pinus contorta) pine trees. These variables were obtained using various modeled, insitu, and remotely sensed sources. The generalized additive model (GAM) was used to calculate the statistical significance of each variable contributing to MPB spread and also created maps identifying habitat suitability. Results indicate vegetation stress and forest disturbance to be variables most indicative of MPB spread. Additionally, the model was able to detect habitat suitability of MPB with a 45% accuracy concluding that a geospatial driven modeling approach can be used to delineate potential MPB spread within SNP.

Assessment of fine-scale resource selection and spatially explicit habitat suitability modelling for a re-introduced tiger (Panthera tigris) population in central India.

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Sarkar, Mriganka Shekhar; Krishnamurthy, Ramesh; Johnson, Jeyaraj A; Sen, Subharanjan; Saha, Goutam Kumar

2017-01-01

Large carnivores influence ecosystem functions at various scales. Thus, their local extinction is not only a species-specific conservation concern, but also reflects on the overall habitat quality and ecosystem value. Species-habitat relationships at fine scale reflect the individuals' ability to procure resources and negotiate intraspecific competition. Such fine scale habitat choices are more pronounced in large carnivores such as tiger ( Panthera tigris ), which exhibits competitive exclusion in habitat and mate selection strategies. Although landscape level policies and conservation strategies are increasingly promoted for tiger conservation, specific management interventions require knowledge of the habitat correlates at fine scale. We studied nine radio-collared individuals of a successfully reintroduced tiger population in Panna Tiger Reserve, central India, focussing on the species-habitat relationship at fine scales. With 16 eco-geographical variables, we performed Manly's selection ratio and K-select analyses to define population-level and individual-level variation in resource selection, respectively. We analysed the data obtained during the exploratory period of six tigers and during the settled period of eight tigers separately, and compared the consequent results. We further used the settled period characteristics to model and map habitat suitability based on the Mahalanobis D 2 method and the Boyce index. There was a clear difference in habitat selection by tigers between the exploratory and the settled period. During the exploratory period, tigers selected dense canopy and bamboo forests, but also spent time near villages and relocated village sites. However, settled tigers predominantly selected bamboo forests in complex terrain, riverine forests and teak-mixed forest, and totally avoided human settlements and agriculture areas. There were individual variations in habitat selection between exploratory and settled periods. Based on threshold limits

Guidelines for using the Delphi Technique to develop habitat suitability index curves

Science.gov (United States)

Crance, Johnie H.

1987-01-01

Habitat Suitability Index (SI) curves are one method of presenting species habitat suitability criteria. The curves are often used with the Habitat Evaluation Procedures (HEP) and are necessary components of the Instream Flow Incremental Methodology (IFIM) (Armour et al. 1984). Bovee (1986) described three categories of SI curves or habitat suitability criteria based on the procedures and data used to develop the criteria. Category I curves are based on professional judgment, with 1ittle or no empirical data. Both Category II (utilization criteria) and Category III (preference criteria) curves have as their source data collected at locations where target species are observed or collected. Having Category II and Category III curves for all species of concern would be ideal. In reality, no SI curves are available for many species, and SI curves that require intensive field sampling often cannot be developed under prevailing constraints on time and costs. One alternative under these circumstances is the development and interim use of SI curves based on expert opinion. The Delphi technique (Pill 1971; Delbecq et al. 1975; Linstone and Turoff 1975) is one method used for combining the knowledge and opinions of a group of experts. The purpose of this report is to describe how the Delphi technique may be used to develop expert-opinion-based SI curves.

Hydrographic influence on the spawning habitat suitability of western Baltic cod (Gadus morhua)

DEFF Research Database (Denmark)

Hüssy, K.; Hinrichsen, H.-H.; Huwer, B.

2012-01-01

Hydrographic influence on the spawning habitat suitability of western Baltic cod (Gadus morhua) – ICES Journal of Marine Science, 69: 1736–1743.Recruitment variability of marine fish is influenced by the reproductive potential of the stock (i.e. stock characteristics and abundance) and the survival...... of early life stages, mediated by environmental conditions of both a physical (water temperature, salinity and oxygen conditions, ocean currents) and a biological nature (i.e. food, predators). The objective of this study is to assess the importance of variability in environmental conditions within...... allowing survival of western Baltic cod eggs indicates that favourable conditions predominantly occurred during the late spawning season in April/May, while minimum survival rates could be expected from January to March. Unsuitable time periods and habitats exhibiting the highest mortality rates...

Assessment of fine-scale resource selection and spatially explicit habitat suitability modelling for a re-introduced tiger (Panthera tigris population in central India

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Mriganka Shekhar Sarkar

2017-11-01

Full Text Available Background Large carnivores influence ecosystem functions at various scales. Thus, their local extinction is not only a species-specific conservation concern, but also reflects on the overall habitat quality and ecosystem value. Species-habitat relationships at fine scale reflect the individuals’ ability to procure resources and negotiate intraspecific competition. Such fine scale habitat choices are more pronounced in large carnivores such as tiger (Panthera tigris, which exhibits competitive exclusion in habitat and mate selection strategies. Although landscape level policies and conservation strategies are increasingly promoted for tiger conservation, specific management interventions require knowledge of the habitat correlates at fine scale. Methods We studied nine radio-collared individuals of a successfully reintroduced tiger population in Panna Tiger Reserve, central India, focussing on the species-habitat relationship at fine scales. With 16 eco-geographical variables, we performed Manly’s selection ratio and K-select analyses to define population-level and individual-level variation in resource selection, respectively. We analysed the data obtained during the exploratory period of six tigers and during the settled period of eight tigers separately, and compared the consequent results. We further used the settled period characteristics to model and map habitat suitability based on the Mahalanobis D2 method and the Boyce index. Results There was a clear difference in habitat selection by tigers between the exploratory and the settled period. During the exploratory period, tigers selected dense canopy and bamboo forests, but also spent time near villages and relocated village sites. However, settled tigers predominantly selected bamboo forests in complex terrain, riverine forests and teak-mixed forest, and totally avoided human settlements and agriculture areas. There were individual variations in habitat selection between exploratory

Predicted Habitat Suitability for Leptoseris in the Au'au Channel Region

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National Oceanic and Atmospheric Administration, Department of Commerce — This raster denotes predicted habitat suitability for Leptoseris in the Au'au Channel region. Maximum Entropy (MaxEnt) modeling software was used to create this...

Predicted Habitat Suitability for Porites in the Au'au Channel Region

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National Oceanic and Atmospheric Administration, Department of Commerce — This raster denotes predicted habitat suitability for Porites in the Au'au Channel region. Maximum Entropy (MaxEnt) modeling software was used to create this...

Future habitat suitability for coral reef ecosystems under global warming and ocean acidification.

Science.gov (United States)

Couce, Elena; Ridgwell, Andy; Hendy, Erica J

2013-12-01

Rising atmospheric CO2 concentrations are placing spatially divergent stresses on the world's tropical coral reefs through increasing ocean surface temperatures and ocean acidification. We show how these two stressors combine to alter the global habitat suitability for shallow coral reef ecosystems, using statistical Bioclimatic Envelope Models rather than basing projections on any a priori assumptions of physiological tolerances or fixed thresholds. We apply two different modeling approaches (Maximum Entropy and Boosted Regression Trees) with two levels of complexity (one a simplified and reduced environmental variable version of the other). Our models project a marked temperature-driven decline in habitat suitability for many of the most significant and bio-diverse tropical coral regions, particularly in the central Indo-Pacific. This is accompanied by a temperature-driven poleward range expansion of favorable conditions accelerating up to 40-70 km per decade by 2070. We find that ocean acidification is less influential for determining future habitat suitability than warming, and its deleterious effects are centered evenly in both hemispheres between 5° and 20° latitude. Contrary to expectations, the combined impact of ocean surface temperature rise and acidification leads to little, if any, degradation in future habitat suitability across much of the Atlantic and areas currently considered 'marginal' for tropical corals, such as the eastern Equatorial Pacific. These results are consistent with fossil evidence of range expansions during past warm periods. In addition, the simplified models are particularly sensitive to short-term temperature variations and their projections correlate well with reported locations of bleaching events. Our approach offers new insights into the relative impact of two global environmental pressures associated with rising atmospheric CO2 on potential future habitats, but greater understanding of past and current controls on coral

Evaluating timber harvesting impacts on wildlife habitat suitability using FOREX

Science.gov (United States)

Chris B. LeDoux

1997-01-01

Precommercial, commercial, and final harvesting operations can impact wildlife habitat suitability by altering the vegetation composition on a given site. Harvesting operations remove trees and many times provide the necessary perturbation to trigger successional conditions different from those that existed prior to the harvest. Although these new successional changes...

The Spatial Suitable Habitat Model of Acacia decurrens in Mount Merbabu National Park

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Yoko Untoro

2017-09-01

Full Text Available Green wattle (Acacia decurrens is an invasive alien species (IAS found in the Mount Merbabu National Park (TNGMb. This study aim to obtain spatially studies on habitat suitability models of A. decurrens in TNGMb region. In fact, this species became as a high invasive and dominance in the TNGMb and contributes the negative impact to the ecosystem. In addition, the result of this study should be useful for controling activities of A. decurrens. Predictor variables in this research were (altitude, slope, rainfall, air temperature, distance from river, NDVI, NDMI, distance from hiking trail, and distance from burnt area. The survey was conducted with random sampling of presence or absence of A. decurrens by marking the coordinate point of location using GPS. Data analysis in this research was used binary logistic regression enter method. Binary logistic regression involves the data acquisition of the presence and absence of A. decurrens as the y variable, while the predictor variable map as the variable x. The type of spatial distribution of A. decurrens in the TNGMb was identified as clumped. The Nagelkerke R2 values obtained in the model was 39,2%, while 60,8% was explained by other variables were not used in the model. The results of the logistic regression model showed a high percentage of suitability of 64,29%, a medium suitability of 28,57%, and a low suitability of 7.14% then the Implications for controlling activities of A. decurrens in TNGMb could be prioritized in high suitability habitat. Keywords: Acacia decurrens, green wattle, invasive, spatial suitable habitat 

Application of GIS to predict malaria hotspots based on Anopheles arabiensis habitat suitability in Southern Africa

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Gwitira, Isaiah; Murwira, Amon; Zengeya, Fadzai M.; Shekede, Munyaradzi Davis

2018-02-01

Malaria remains a major public health problem and a principal cause of morbidity and mortality in most developing countries. Although malaria still presents health problems, significant successes have been recorded in reducing deaths resulting from the disease. As malaria transmission continues to decline, control interventions will increasingly depend on the ability to define high-risk areas known as malaria hotspots. Therefore, there is urgent need to use geospatial tools such as geographic information system to detect spatial patterns of malaria and delineate disease hot spots for better planning and management. Thus, accurate mapping and prediction of seasonality of malaria hotspots is an important step towards developing strategies for effective malaria control. In this study, we modelled seasonal malaria hotspots as a function of habitat suitability of Anopheles arabiensis (A. Arabiensis) as a first step towards predicting likely seasonal malaria hotspots that could provide guidance in targeted malaria control. We used Geographical information system (GIS) and spatial statistic methods to identify seasonal hotspots of malaria cases at the country level. In order to achieve this, we first determined the spatial distribution of seasonal malaria hotspots using the Getis Ord Gi* statistic based on confirmed positive malaria cases recorded at health facilities in Zimbabwe over four years (1996-1999). We then used MAXENT technique to model habitat suitability of A. arabiensis from presence data collected from 1990 to 2002 based on bioclimatic variables and altitude. Finally, we used autologistic regression to test the extent to which malaria hotspots can be predicted using A. arabiensis habitat suitability. Our results show that A. arabiensis habitat suitability consistently and significantly (p < 0.05) predicts malaria hotspots from 1996 to 1999. Overall, our results show that malaria hotspots can be predicted using A. arabiensis habitat suitability, suggesting

Hydropower Production and Fish Habitat Suitability: Impact and Effectiveness of Environmental Flow Prescriptions

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Castellarin, A.; Galeati, G.; Ceola, S.; Pugliese, A.; Ventura, M.; Montanari, A.

2017-12-01

The anthropogenic alteration of the natural flow regime of a river for hydropower production can significantly modify the processes and functions associated with fluvial ecosystems. In order to preserve the fluvial habitat downstream of dams and diversion structures, environmental flows are commonly defined. Such environmental flows are generally computed from empirical methodologies, which are seldom based on site-specific studies, and may not be representative of local ecological and hydraulic conditions. Here we present the results of a quantitative analysis on the effectiveness of two alternative environmental flow scenarios prescribed in Central Italy (time-invariant experimental and empirically-based flow release versus time-variant hydrogeomorphologically-based flow release) and their impact on hydropower production and fish habitat suitability. The latter is examined by means of several models of habitat suitability curve, which is a well-known approach capable of analysing fluvial species preferences as a function of key eco-hydraulic features, such as water depth, flow velocity and river substrate. The results show an evident loss of hydropower production moving from the time-invariant experimental flow release to the hydrogeomorphological one (nearly 20% at the annual scale). Concerning the effects in terms of fish habitat suitability, our outcomes are less obvious, since they are species- and life stage-specific. The proposed analysis, which can be easily adapted to different riparian habitats and hydrological contexts, is a useful tool to guide the derivation of optimal water resource management strategies in order to ensure both hydropower production and fluvial ecosystem protection.

Predicted Habitat Suitability for Montipora Corals in the Au'au Channel Region

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National Oceanic and Atmospheric Administration, Department of Commerce — This raster denotes predicted habitat suitability for Montipora in the Au'au Channel region. Maximum Entropy (MaxEnt) modeling software was used to create this...

Predicted Habitat Suitability for Leptoseris Corals in the Au'au Channel Region

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National Oceanic and Atmospheric Administration, Department of Commerce — This raster denotes predicted habitat suitability for Leptoseris in the Au'au Channel region. Maximum Entropy (MaxEnt) modeling software was used to create this...

Development of habitat suitability criteria for Neotropical stream fishes and an assessment of their transferability to streams with different conservation status

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Fabrício Barreto Teresa

Full Text Available We assessed the preference of 10 fish species for depth and velocity conditions in forested streams from southeastern Brazil using habitat suitability criteria (HSC curves. We also tested whether preference patterns observed in forested streams can be transferred to deforested streams. We used data from fish sampled in 62 five-meter sites in three forested streams to construct preference curves. Astyanax altiparanae, A. fasciatus, Knodus moenkhausii, and Piabina argentea showed a preference for deep slow habitats, whereas Aspidoras fuscoguttatus, Characidium zebra, Cetopsorhamdia iheringi, Pseudopimelodus pulcher, and Hypostomus nigromaculatus showed an opposite pattern: preference for shallow fast habitats. Hypostomus ancistroides showed a multimodal pattern of preference for depth and velocity. To evaluate whether patterns observed in forested streams may be transferred to deforested streams, we sampled 64 five-meters sites in three deforested streams using the same methodology. The preference for velocity was more consistent than for depth, as success in the transferability criterion was 86% and 29% of species, respectively. This indicates that velocity is a good predictor of species abundance in streams, regardless of their conditionNeste estudo avaliamos a preferência de 10 espécies de peixes por condições de profundidade e fluxo em riachos florestados do sudeste do Brasil por meio do critério de adequabilidade de habitat (habitat suitability criteria - curvas HSC. Testamos também se os padrões de preferência observados nos riachos florestados podem ser transferidos para riachos desmatados. Foram realizadas amostragens da ictiofauna em 62 trechos de cinco metros de extensão em três riachos florestados para a construção das curvas de preferência. Astyanax altiparanae, A. fasciatus, Knodus moenkhausii e Piabina argentea apresentaram preferência por habitats lentos e profundos, enquanto Aspidoras fuscoguttatus, Characidium zebra

Hydro-power production and fish habitat suitability: Assessing impact and effectiveness of ecological flows at regional scale

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Ceola, Serena; Pugliese, Alessio; Ventura, Matteo; Galeati, Giorgio; Montanari, Alberto; Castellarin, Attilio

2018-06-01

Anthropogenic activities along streams and rivers may be of major concern for fluvial ecosystems, e.g. abstraction and impoundment of surface water resources may profoundly alter natural streamflow regimes. An established approach aimed at preserving the behavior and distribution of fluvial species relies on the definition of ecological flows (e-flows) downstream of dams and diversion structures. E-flow prescriptions are usually set by basin authorities at regional scale, often without a proper assessment of their impact and effectiveness. On the contrary, we argue that e-flows should be identified on the basis of (i) regional and (ii) quantitative assessments. We focus on central Italy and evaluate the effects on habitat suitability of two near-threatened fish species (i.e. Barbel and Chub) and an existing hydro-power network when shifting from the current time-invariant e-flow policy to a tighter and seasonally-varying soon-to-be-enforced one. Our example clearly shows that: (a) quantitative regional scale assessments are viable even when streamflow observations are entirely missing at study sites; (b) aprioristic e-flows policies may impose releases that exceed natural streamflows for significantly long time intervals (weeks, or months); (c) unduly tightening e-flow policies may heavily impact regional hydro-power productivity (15% and 42% losses on annual and seasonal basis, respectively), yet resulting in either marginal or negligible improvements of fluvial ecosystem.

Coral Reef Habitat Suitability in Future Climate Scenarios from NCAR CESM1 considering a Suite of Biogeochemical Variables

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Freeman, L. A.; Kleypas, J. A.; Miller, A. J.

2013-12-01

A maximum entropy species distribution model (Maxent) is used to describe coral reef habitat in current climate conditions and to predict changes to that habitat during the 21st century. Two climate change scenarios (RCP4.5 and RCP8.5) from the National Center for Atmospheric Research's Community Earth System Model version 1 (CESM1) were used with Maxent to determine environmental suitability for the family of corals Scleractina in 1° by 1° cells. Input environmental variables most suitable for representing coral habitat limitation are isolated using a principal component analysis and include cumulative thermal stress, salinity, light availability, current speed, phosphate levels and aragonite saturation state. Considering a suite of environmental variables allows for a more synergistic view of future habitat suitability, although individual variables are found to be limiting in certain areas- for example, aragonite saturation state is limiting at higher latitudes. Climate-driven coral reef habitat changes depend strongly on the oceanic region of interest and the region of corals used to train the niche model. Increased global coral habitat loss occurred in both RCP4.5 and RCP8.5 climate projections as time progressed through the 21th century. Maximum suitable habitat loss was 82% by 2100 for RCP8.5. When only Caribbean/Atlantic coral reef environmental data is applied globally, 88% of global habitat was lost by 2100 for RCP8.5. The global runs utilizing only Pacific Ocean reefs' ability to survive showed the most significant worldwide loss, 90% by 2100 for RCP8.5. When Maxent was trained with Indian Ocean reefs, an increase in suitable habitat worldwide was estimated. Habitat suitability was found to increase by 38% in RCP4.5 by 2100 and 28% in RCP8.5 by 2050. This suggests that shallow tropical sites in the Indian Ocean basin experience conditions today that are most similar to future worldwide climate projections. Indian Ocean reefs may be ideal candidate

A Modelling Framework to Assess the Effect of Pressures on River Abiotic Habitat Conditions and Biota.

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Jochem Kail

Full Text Available River biota are affected by global reach-scale pressures, but most approaches for predicting biota of rivers focus on river reach or segment scale processes and habitats. Moreover, these approaches do not consider long-term morphological changes that affect habitat conditions. In this study, a modelling framework was further developed and tested to assess the effect of pressures at different spatial scales on reach-scale habitat conditions and biota. Ecohydrological and 1D hydrodynamic models were used to predict discharge and water quality at the catchment scale and the resulting water level at the downstream end of a study reach. Long-term reach morphology was modelled using empirical regime equations, meander migration and 2D morphodynamic models. The respective flow and substrate conditions in the study reach were predicted using a 2D hydrodynamic model, and the suitability of these habitats was assessed with novel habitat models. In addition, dispersal models for fish and macroinvertebrates were developed to assess the re-colonization potential and to finally compare habitat suitability and the availability/ability of species to colonize these habitats. Applicability was tested and model performance was assessed by comparing observed and predicted conditions in the lowland Treene River in northern Germany. Technically, it was possible to link the different models, but future applications would benefit from the development of open source software for all modelling steps to enable fully automated model runs. Future research needs concern the physical modelling of long-term morphodynamics, feedback of biota (e.g., macrophytes on abiotic habitat conditions, species interactions, and empirical data on the hydraulic habitat suitability and dispersal abilities of macroinvertebrates. The modelling framework is flexible and allows for including additional models and investigating different research and management questions, e.g., in climate impact

Habitat suitability index model of the sea cucumber Apostichopus japonicus (Selenka): A case study of Shandong Peninsula, China.

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Zhang, Zhipeng; Zhou, Jian; Song, Jingjing; Wang, Qixiang; Liu, Hongjun; Tang, Xuexi

2017-09-15

A habitat suitability index (HSI) model for the sea cucumber Apostichopus japonicus (Selenka) was established in the present study. Based on geographic information systems, the HSI model was used to identify potential sites around the Shandong Peninsula suitable for restoration of immature (25g) A. japonicus. Six habitat factors were used as input variables for the HSI model: sediment classification, water temperature, salinity, water depth, pH and dissolved oxygen. The weighting of each habitat factor was defined through the Delphi method. Sediment classification was the most important condition affecting the HSI of A. japonicus in the different study areas, while water temperature was the most important condition in different seasons. The HSI of Western Laizhou Bay was relatively low, meaning the site was not suitable for aquaculture-based restoration of A. japonicus. In contrast, Xiaoheishan Island, Rongcheng Bay and Qingdao were preferable sites, suitable as habitats for restoration efforts. Copyright © 2017 Elsevier Ltd. All rights reserved.

Shifts in the suitable habitat available for brown trout (Salmo trutta L.) under short-term climate change scenarios.

Science.gov (United States)

Muñoz-Mas, R; Lopez-Nicolas, A; Martínez-Capel, F; Pulido-Velazquez, M

2016-02-15

The impact of climate change on the habitat suitability for large brown trout (Salmo trutta L.) was studied in a segment of the Cabriel River (Iberian Peninsula). The future flow and water temperature patterns were simulated at a daily time step with M5 models' trees (NSE of 0.78 and 0.97 respectively) for two short-term scenarios (2011-2040) under the representative concentration pathways (RCP 4.5 and 8.5). An ensemble of five strongly regularized machine learning techniques (generalized additive models, multilayer perceptron ensembles, random forests, support vector machines and fuzzy rule base systems) was used to model the microhabitat suitability (depth, velocity and substrate) during summertime and to evaluate several flows simulated with River2D©. The simulated flow rate and water temperature were combined with the microhabitat assessment to infer bivariate habitat duration curves (BHDCs) under historical conditions and climate change scenarios using either the weighted usable area (WUA) or the Boolean-based suitable area (SA). The forecasts for both scenarios jointly predicted a significant reduction in the flow rate and an increase in water temperature (mean rate of change of ca. -25% and +4% respectively). The five techniques converged on the modelled suitability and habitat preferences; large brown trout selected relatively high flow velocity, large depth and coarse substrate. However, the model developed with support vector machines presented a significantly trimmed output range (max.: 0.38), and thus its predictions were banned from the WUA-based analyses. The BHDCs based on the WUA and the SA broadly matched, indicating an increase in the number of days with less suitable habitat available (WUA and SA) and/or with higher water temperature (trout will endure impoverished environmental conditions ca. 82% of the days). Finally, our results suggested the potential extirpation of the species from the study site during short time spans. Copyright © 2015

Predicting spatial and temporal distribution of Indo-Pacific lionfish (Pterois volitans) in Biscayne Bay through habitat suitability modeling

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Bernal, Nicholas A.; DeAngelis, Donald L.; Schofield, Pamela J.; Sullivan Sealey, Kathleen

2014-01-01

Invasive species may exhibit higher levels of growth and reproduction when environmental conditions are most suitable, and thus their effects on native fauna may be intensified. Understanding potential impacts of these species, especially in the nascent stages of a biological invasion, requires critical information concerning spatial and temporal distributions of habitat suitability. Using empirically supported environmental variables (e.g., temperature, salinity, dissolved oxygen, rugosity, and benthic substrate), our models predicted habitat suitability for the invasive lionfish (Pterois volitans) in Biscayne Bay, Florida. The use of Geographic Information Systems (GIS) as a platform for the modeling process allowed us to quantify correlations between temporal (seasonal) fluctuations in the above variables and the spatial distribution of five discrete habitat quality classes, whose ranges are supported by statistical deviations from the apparent best conditions described in prior studies. Analysis of the resulting models revealed little fluctuation in spatial extent of the five habitat classes on a monthly basis. Class 5, which represented the area with environmental variables closest to the best conditions for lionfish, occupied approximately one-third of Biscayne Bay, with subsequent habitats declining in area. A key finding from this study was that habitat suitability increased eastward from the coastline, where higher quality habitats were adjacent to the Atlantic Ocean and displayed marine levels of ambient water quality. Corroboration of the models with sightings from the USGS-NAS database appeared to support our findings by nesting 79 % of values within habitat class 5; however, field testing (i.e., lionfish surveys) is necessary to confirm the relationship between habitat classes and lionfish distribution.

Prospects for population expansion of the exotic aoudad (Ammotragus lervia; Bovidae) in the Iberian Peninsula: clues from habitat suitability modelling

DEFF Research Database (Denmark)

Cassinello, Jorge; Acevedo, Pelayo; Hortal, Joaquín

2006-01-01

We studied the geographical distribution and habitat suitability of an introduced ungulate, the aoudad (Ammotragus lervia), that is currently expanding its range in south-eastern Iberian Peninsula. We assessed the niche of the species using Ecological Niche Factor Analysis (ENFA) on (1......) environmental variables (climate and habitat type), and (2) potential aoudad landscape avoidance and human disturbance variables. We compared both niche descriptions to study the impact of human interference on niche selection of the species. ENFA models were calibrated using data on the population expanded...

Temporal habitat suitability modeling of Caspian shad (Alosa spp. in the southern Caspian Sea

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Ali Haghi Vayghan

2015-11-01

Full Text Available To comprehensively manage an ecosystem such as that of the Caspian Sea, the world’s largest lake, detailed knowledge of the habitat traits of the living organisms in the ecosystem is essential. The present study examined environmental variables and used the Habitat Suitability Index (HSI model to determine the most preferred seasonal habitat and optimal environmental range of Caspian shad (Alosa spp. The fish preferred deep waters with low levels of total organic matter and sea level anomaly in winter and productive areas with a high concentration of chlorophyll-a (Chla and relatively high benthos biomass in spring. The number per unit area (NPUA-based HSI model determined that the geometric mean model (GMM was the optimal model for defining a suitable habitat in winter. For spring, the arithmetic mean model (or GMM in the NPUA-based HSI model most accurately predicted preferred habitat for Caspian shad. The average NPUA in both seasons increased with the HSI; areas with an HSI of between 0.4 and 0.6 in spring and between 0.6 and 0.8 in winter had a high percentage of total catch. Areas with an HSI of more than 0.5 had over 91% and 63% of the total catch in spring and winter, respectively, demonstrating the reliability of the NPUA-based HSI model in predicting Caspian shad habitat. The present study shows that remotely sensed data plus depth are the most critical environmental variables in Caspian shad habitats and that Chla and SLA are the most critical remotely sensed parameters for near real-time prediction of Caspian shad habitat.

Climate change and tree-line ecosystems in the Sierra Nevada: Habitat suitability modelling to inform high-elevation forest dynamics monitoring

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Moore, Peggy E.; Alvarez, Otto; McKinney, Shawn T.; Li, Wenkai; Brooks, Matthew L.; Guo, Qinghua

2017-01-01

.Overall, models indicated that suitable habitats for whitebark and foxtail pine are more likely to shift geographically within the parks by 2100 rather than decline precipitously. This implies park managers might focus conservation efforts on stressors other than climate change, working toward species resilience in the face of threats from introduced disease and elevated native insect damage. More specifically, further understanding of the incidence and severity of white pine blister rust and other stressors in high elevation white pines would help assess vulnerability from threats other than climate change.

Habitat suitability models for cavity-nesting birds in a postfire landscape

Science.gov (United States)

Robin E. Russell; Victoria A. Saab; Jonathan G. Dudley

2007-01-01

Models of habitat suitability in postfire landscapes are needed by land managers to make timely decisions regarding postfire timber harvest and other management activities. Many species of cavity-nesting birds are dependent on postfire landscapes for breeding and other aspects of their life history and are responsive to postfire management activities (e.g., timber...

Predicted Habitat Suitability for All Mesophotic Corals in the Au'au Channel Region

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National Oceanic and Atmospheric Administration, Department of Commerce — This raster denotes predicted habitat suitability for all mesophotic corals in the Au'au Channel region. Maximum Entropy (MaxEnt) modeling software was used to...

Global Habitat Suitability and Ecological Niche Separation in the Phylum Placozoa.

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Omid Paknia

Full Text Available The enigmatic placozoans, which hold a key position in the metazoan Tree of Life, have attracted substantial attention in many areas of biological and biomedical research. While placozoans have become an emerging model system, their ecology and particularly biogeography remain widely unknown. In this study, we use modelling approaches to explore habitat preferences, and distribution pattern of the placozoans phylum. We provide hypotheses for discrete ecological niche separation between genetic placozoan lineages, which may also help to understand biogeography patterns in other small marine invertebrates. We, here, used maximum entropy modelling to predict placozoan distribution using 20 environmental grids of 9.2 km2 resolution. In addition, we used recently developed metrics of niche overlap to compare habitat suitability models of three genetic clades. The predicted distributions range from 55°N to 44°S and are restricted to regions of intermediate to warm sea surface temperatures. High concentrations of salinity and low nutrient concentrations appear as secondary factors. Tests of niche equivalency reveal the largest differences between placozoan clades I and III. Interestingly, the genetically well-separated clades I and V appear to be ecologically very similar. Our habitat suitability models predict a wider latitudinal distribution for placozoans, than currently described, especially in the northern hemisphere. With respect to biogeography modelling, placozoans show patterns somewhere between higher metazoan taxa and marine microorganisms, with the first group usually showing complex biogeographies and the second usually showing "no biogeography."

Pan-Arctic sea ice-algal chl a biomass and suitable habitat are largely underestimated for multiyear ice.

Science.gov (United States)

Lange, Benjamin A; Flores, Hauke; Michel, Christine; Beckers, Justin F; Bublitz, Anne; Casey, John Alec; Castellani, Giulia; Hatam, Ido; Reppchen, Anke; Rudolph, Svenja A; Haas, Christian

2017-11-01

There is mounting evidence that multiyear ice (MYI) is a unique component of the Arctic Ocean and may play a more important ecological role than previously assumed. This study improves our understanding of the potential of MYI as a suitable habitat for sea ice algae on a pan-Arctic scale. We sampled sea ice cores from MYI and first-year sea ice (FYI) within the Lincoln Sea during four consecutive spring seasons. This included four MYI hummocks with a mean chl a biomass of 2.0 mg/m 2 , a value significantly higher than FYI and MYI refrozen ponds. Our results support the hypothesis that MYI hummocks can host substantial ice-algal biomass and represent a reliable ice-algal habitat due to the (quasi-) permanent low-snow surface of these features. We identified an ice-algal habitat threshold value for calculated light transmittance of 0.014%. Ice classes and coverage of suitable ice-algal habitat were determined from snow and ice surveys. These ice classes and associated coverage of suitable habitat were applied to pan-Arctic CryoSat-2 snow and ice thickness data products. This habitat classification accounted for the variability of the snow and ice properties and showed an areal coverage of suitable ice-algal habitat within the MYI-covered region of 0.54 million km 2 (8.5% of total ice area). This is 27 times greater than the areal coverage of 0.02 million km 2 (0.3% of total ice area) determined using the conventional block-model classification, which assigns single-parameter values to each grid cell and does not account for subgrid cell variability. This emphasizes the importance of accounting for variable snow and ice conditions in all sea ice studies. Furthermore, our results indicate the loss of MYI will also mean the loss of reliable ice-algal habitat during spring when food is sparse and many organisms depend on ice-algae. © 2017 The Authors. Global Change Biology Published by John Wiley & Sons Ltd.

Shaken but not stirred: Multiscale habitat suitability modeling of sympatric marten species (Martes martes and Martes foina) in the northern Iberian Peninsula

Science.gov (United States)

Maria Vergara; Samuel A. Cushman; Fermin Urra; Aritz Ruiz-Gonzalez

2016-01-01

Multispecies and multiscale habitat suitability models (HSM) are important to identify the environmental variables and scales influencing habitat selection and facilitate the comparison of closely related species with different ecological requirements. Objectives This study explores the multiscale relationships of habitat suitability for the pine (Martes...

Using forest inventory data to assess fisher resting habitat suitability in California.

Science.gov (United States)

William J. Zielinski; Richard L. Truex; Jeffrey R. Dunk; Tom Gaman

2006-01-01

The fisher (Martes pennanti) is a forest-dwelling carnivore whose current distribution and association with late-seral forest conditions make it vulnerable to stand-altering human activities or natural disturbances. Fishers select a variety of structures for daily resting bouts. These habitat elements, together with foraging and reproductive (denning) habitat,...

Water-quality models to assess algal community dynamics, water quality, and fish habitat suitability for two agricultural land-use dominated lakes in Minnesota, 2014

Science.gov (United States)

Smith, Erik A.; Kiesling, Richard L.; Ziegeweid, Jeffrey R.

2017-07-20

Fish habitat can degrade in many lakes due to summer blue-green algal blooms. Predictive models are needed to better manage and mitigate loss of fish habitat due to these changes. The U.S. Geological Survey (USGS), in cooperation with the Minnesota Department of Natural Resources, developed predictive water-quality models for two agricultural land-use dominated lakes in Minnesota—Madison Lake and Pearl Lake, which are part of Minnesota’s sentinel lakes monitoring program—to assess algal community dynamics, water quality, and fish habitat suitability of these two lakes under recent (2014) meteorological conditions. The interaction of basin processes to these two lakes, through the delivery of nutrient loads, were simulated using CE-QUAL-W2, a carbon-based, laterally averaged, two-dimensional water-quality model that predicts distribution of temperature and oxygen from interactions between nutrient cycling, primary production, and trophic dynamics.The CE-QUAL-W2 models successfully predicted water temperature and dissolved oxygen on the basis of the two metrics of mean absolute error and root mean square error. For Madison Lake, the mean absolute error and root mean square error were 0.53 and 0.68 degree Celsius, respectively, for the vertical temperature profile comparisons; for Pearl Lake, the mean absolute error and root mean square error were 0.71 and 0.95 degree Celsius, respectively, for the vertical temperature profile comparisons. Temperature and dissolved oxygen were key metrics for calibration targets. These calibrated lake models also simulated algal community dynamics and water quality. The model simulations presented potential explanations for persistently large total phosphorus concentrations in Madison Lake, key differences in nutrient concentrations between these lakes, and summer blue-green algal bloom persistence.Fish habitat suitability simulations for cool-water and warm-water fish indicated that, in general, both lakes contained a large

Predicting Species Distributions Using Record Centre Data: Multi-Scale Modelling of Habitat Suitability for Bat Roosts.

Science.gov (United States)

Bellamy, Chloe; Altringham, John

2015-01-01

Conservation increasingly operates at the landscape scale. For this to be effective, we need landscape scale information on species distributions and the environmental factors that underpin them. Species records are becoming increasingly available via data centres and online portals, but they are often patchy and biased. We demonstrate how such data can yield useful habitat suitability models, using bat roost records as an example. We analysed the effects of environmental variables at eight spatial scales (500 m - 6 km) on roost selection by eight bat species (Pipistrellus pipistrellus, P. pygmaeus, Nyctalus noctula, Myotis mystacinus, M. brandtii, M. nattereri, M. daubentonii, and Plecotus auritus) using the presence-only modelling software MaxEnt. Modelling was carried out on a selection of 418 data centre roost records from the Lake District National Park, UK. Target group pseudoabsences were selected to reduce the impact of sampling bias. Multi-scale models, combining variables measured at their best performing spatial scales, were used to predict roosting habitat suitability, yielding models with useful predictive abilities. Small areas of deciduous woodland consistently increased roosting habitat suitability, but other habitat associations varied between species and scales. Pipistrellus were positively related to built environments at small scales, and depended on large-scale woodland availability. The other, more specialist, species were highly sensitive to human-altered landscapes, avoiding even small rural towns. The strength of many relationships at large scales suggests that bats are sensitive to habitat modifications far from the roost itself. The fine resolution, large extent maps will aid targeted decision-making by conservationists and planners. We have made available an ArcGIS toolbox that automates the production of multi-scale variables, to facilitate the application of our methods to other taxa and locations. Habitat suitability modelling has the

Present and Future Projections of Habitat Suitability of the Asian Tiger Mosquito, a Vector of Viral Pathogens, from Global Climate Simulations.

Science.gov (United States)

Proestos, Y.; Christophides, G.; Erguler, K.; Tanarhte, M.; Waldock, J.; Lelieveld, J.

2014-12-01

Climate change can influence the transmission of vector borne diseases (VBDs) through altering the habitat suitability of insect vectors. Here we present global climate model simulations and evaluate the associated uncertainties in view of the main meteorological factors that may affect the distribution of the Asian Tiger mosquito (Aedes albopictus), which can transmit pathogens that cause Chikungunya, Dengue fever, yellow fever and various encephalitides. Using a general circulation model (GCM) at 50 km horizontal resolution to simulate mosquito survival variables including temperature, precipitation and relative humidity, we present both global and regional projections of the habitat suitability up to the middle of the 21st century. The model resolution of 50 km allows evaluation against previous projections for Europe and provides a basis for comparative analyses with other regions. Model uncertainties and performance are addressed in light of the recent CMIP5 ensemble climate model simulations for the RCP8.5 concentration pathway and using meteorological re-analysis data (ERA-Interim/ECMWF) for the recent past. Uncertainty ranges associated with the thresholds of meteorological variables that may affect the distribution of Ae. albopictus are diagnosed using fuzzy-logic methodology, notably to assess the influence of selected meteorological criteria and combinations of criteria that influence mosquito habitat suitability. From the climate projections for 2050, and adopting a habitat suitability index larger than 70%, we estimate that about 2.4 billion individuals in a land area of nearly 20 million square kilometres will potentially be exposed to Ae. albopictus. The synthesis of fuzzy-logic based on mosquito biology and climate change analysis provides new insights into the regional and global spreading of VBDs to support disease control and policy making.

A GIS model of habitat suitability for Solanum conocarpum (Solanaceae) in St. John, US Virgin Islands

Science.gov (United States)

Palumbo, Matthew D.; Fleming, Jonathan P.; Monsegur, Omar A.; Vilella, Francisco

2016-01-01

Solanum conocarpum (Solanaceae) (Marron Bacora) is a rare, dry-forest shrub endemic to the island of St. John, US Virgin Islands, considered for listing under the Endangered Species Act. Given its status as a species of conservation concern, we incorporated environmental characteristics of 3 observed populations and 5 additional known locations into a geographic information system (GIS) analysis to create a habitat-suitability model for the species on the island of St. John. Our model identified 1929.87 ha of highly suitable and moderately suitable habitat. Of these, 1161.20 ha (60.2%) occurred within the boundaries of Virgin Islands National Park. Our model provides spatial information on potential locations for future surveys and restoration sites for this endemic species of the US Virgin Islands.

Models to predict suitable habitat for juvenile bull trout in Washington state

Science.gov (United States)

Jason B. Dunham; G. L. Chandler

2001-01-01

This report describes results of research conducted in 2000 to develop models of suitable habitat for juvenile bull trout (Salvelinus confluentus) in Washington State. The research is associated with a cooperative agreement (Agreement #134100H001) between U.S. Fish and Wildlife Service (USFWS) and the U.S. Forest Service, Rocky Mountain Research...

Assessing habitat connectivity for ground-dwelling animals in an urban environment.

Science.gov (United States)

Braaker, S; Moretti, M; Boesch, R; Ghazoul, J; Obrist, M K; Bontadina, F

To ensure viable species populations in fragmented landscapes, individuals must be able to move between suitable habitat patches. Despite the increased interest in biodiversity assessment in urban environments, the ecological relevance of habitat connectivity in highly fragmented landscapes remains largely unknown. The first step to understanding the role of habitat connectivity in urban ecology is the challenging task of assessing connectivity in the complex patchwork of contrasting habitats that is found in cities. We developed a data-based framework, minimizing the use of subjective assumptions, to assess habitat connectivity that consists of the following sequential steps: (1) identification of habitat preference based on empirical habitat-use data; (2) derivation of habitat resistance surfaces evaluating various transformation functions; (3) modeling of different connectivity maps with electrical circuit theory (Circuitscape), a method considering all possible pathways across the landscape simultaneously; and (4) identification of the best connectivity map with information-theoretic model selection. We applied this analytical framework to assess habitat connectivity for the European hedgehog Erinaceus europaeus, a model species for ground-dwelling animals, in the city of Zurich, Switzerland, using GPS track points from 40 individuals. The best model revealed spatially explicit connectivity “pinch points,” as well as multiple habitat connections. Cross-validation indicated the general validity of the selected connectivity model. The results show that both habitat connectivity and habitat quality affect the movement of urban hedgehogs (relative importance of the two variables was 19.2% and 80.8%, respectively), and are thus both relevant for predicting urban animal movements. Our study demonstrates that even in the complex habitat patchwork of cities, habitat connectivity plays a major role for ground-dwelling animal movement. Data-based habitat connectivity

Climate Change, Northern Birds of Conservation Concern and Matching the Hotspots of Habitat Suitability with the Reserve Network

Science.gov (United States)

Virkkala, Raimo; Heikkinen, Risto K.; Fronzek, Stefan; Leikola, Niko

2013-01-01

National reserve networks are one of the most important means of species conservation, but their efficiency may be diminished due to the projected climatic changes. Using bioclimatic envelope models and spatial data on habitats and conservation areas, we studied how efficient the reserve network will be in preserving 100 forest, mire, marshland, and alpine bird species of conservation concern in Finland in 2051–2080 under three different climate scenarios. The occurrences of the studied bird species were related to the amount of habitat preferred by each species in the different boreal zones. We employed a novel integrated habitat suitability index that takes into account both the species’ probability of occurrence from the bioclimatic models and the availability of suitable habitat. Using this suitability index, the distribution of the topmost 5% suitability squares (“hotspots”) in the four bird species groups in the period 1971–2000 and under the three scenarios were compared with the location of reserves with the highest amounts of the four habitats to study the efficiency of the network. In species of mires, marshlands, and Arctic mountains, a high proportion of protected habitat was included in the 5% hotspots in the scenarios in 2051–2080, showing that protected areas cover a high proportion of occurrences of bird species. In contrast, in forests in the southern and middle boreal zones, only a small proportion of the protected habitat was included in the 5% hotspots, indicating that the efficiency of the protected area network will be insufficient for forest birds in the future. In the northern boreal zone, the efficiency of the reserve network in forests was highly dependent on the strength of climate change varying between the scenarios. Overall, there is no single solution to preserving biodiversity in a changing climate, but several future pathways should be considered. PMID:23700420

Predicting the effects of proposed Mississippi River diversions on oyster habitat quality; application of an oyster habitat suitability index model

Science.gov (United States)

Soniat, Thomas M.; Conzelmann, Craig P.; Byrd, Jason D.; Roszell, Dustin P.; Bridevaux, Joshua L.; Suir, Kevin J.; Colley, Susan B.

2013-01-01

In an attempt to decelerate the rate of coastal erosion and wetland loss, and protect human communities, the state of Louisiana developed its Comprehensive Master Plan for a Sustainable Coast. The master plan proposes a combination of restoration efforts including shoreline protection, marsh creation, sediment diversions, and ridge, barrier island, and hydrological restoration. Coastal restoration projects, particularly the large-scale diversions of fresh water from the Mississippi River, needed to supply sediment to an eroding coast potentially impact oyster populations and oyster habitat. An oyster habitat suitability index model is presented that evaluates the effects of a proposed sediment and freshwater diversion into Lower Breton Sound. Voluminous freshwater, needed to suspend and broadly distribute river sediment, will push optimal salinities for oysters seaward and beyond many of the existing reefs. Implementation and operation of the Lower Breton Sound diversion structure as proposed would render about 6,173 ha of hard bottom immediately east of the Mississippi River unsuitable for the sustained cultivation of oysters. If historical harvests are to be maintained in this region, a massive and unprecedented effort to relocate private leases and restore oyster bottoms would be required. Habitat suitability index model results indicate that the appropriate location for such efforts are to the east and north of the Mississippi River Gulf Outlet.

Re-establishing the pecking order: Niche models reliably predict suitable habitats for the reintroduction of red-billed oxpeckers.

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Kalle, Riddhika; Combrink, Leigh; Ramesh, Tharmalingam; Downs, Colleen T

2017-03-01

Distributions of avian mutualists are affected by changes in biotic interactions and environmental conditions driven directly/indirectly by human actions. The range contraction of red-billed oxpeckers ( Buphagus erythrorhynchus ) in South Africa is partly a result of the widespread use of acaracides (i.e., mainly cattle dips), toxic to both ticks and oxpeckers. We predicted the habitat suitability of red-billed oxpeckers in South Africa using ensemble models to assist the ongoing reintroduction efforts and to identify new reintroduction sites for population recovery. The distribution of red-billed oxpeckers was influenced by moderate to high tree cover, woodland habitats, and starling density (a proxy for cavity-nesting birds) with regard to nest-site characteristics. Consumable resources (host and tick density), bioclimate, surface water body density, and proximity to protected areas were other influential predictors. Our models estimated 42,576.88-98,506.98 km 2 of highly suitable habitat (0.5-1) covering the majority of Limpopo, Mpumalanga, North West, a substantial portion of northern KwaZulu-Natal (KZN) and the Gauteng Province. Niche models reliably predicted suitable habitat in 40%-61% of the reintroduction sites where breeding is currently successful. Ensemble, boosted regression trees and generalized additive models predicted few suitable areas in the Eastern Cape and south of KZN that are part of the historic range. A few southern areas in the Northern Cape, outside the historic range, also had suitable sites predicted. Our models are a promising decision support tool for guiding reintroduction programs at macroscales. Apart from active reintroductions, conservation programs should encourage farmers and/or landowners to use oxpecker-compatible agrochemicals and set up adequate nest boxes to facilitate the population recovery of the red-billed oxpecker, particularly in human-modified landscapes. To ensure long-term conservation success, we suggest that

Evaluating methods to establish habitat suitability criteria: A case study in the upper Delaware River Basin, USA

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Galbraith, Heather S.; Blakeslee, Carrie J.; Cole, Jeffrey C.; Talbert, Colin; Maloney, Kelly O.

2016-01-01

Defining habitat suitability criteria (HSC) of aquatic biota can be a key component to environmental flow science. HSC can be developed through numerous methods; however, few studies have evaluated the consistency of HSC developed by different methodologies. We directly compared HSC for depth and velocity developed by the Delphi method (expert opinion) and by two primary literature meta-analyses (literature-derived range and interquartile range) to assess whether these independent methods produce analogous criteria for multiple species (rainbow trout, brown trout, American shad, and shallow fast guild) and life stages. We further evaluated how these two independently developed HSC affect calculations of habitat availability under three alternative reservoir management scenarios in the upper Delaware River at a mesohabitat (main channel, stream margins, and flood plain), reach, and basin scale. In general, literature-derived HSC fell within the range of the Delphi HSC, with highest congruence for velocity habitat. Habitat area predicted using the Delphi HSC fell between the habitat area predicted using two literature-derived HSC, both at the basin and the site scale. Predicted habitat increased in shallow regions (stream margins and flood plain) using literature-derived HSC while Delphi-derived HSC predicted increased channel habitat. HSC generally favoured the same reservoir management scenario; however, no favoured reservoir management scenario was the most common outcome when applying the literature range HSC. The differences found in this study lend insight into how different methodologies can shape HSC and their consequences for predicted habitat and water management decisions. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

An approach of habitat degradation assessment for characterization on coastal habitat conservation tendency.

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Zhou, Xi-Yin; Lei, Kun; Meng, Wei

2017-09-01

Coastal zones are population and economy highly intensity regions all over the world, and coastal habitat supports the sustainable development of human society. The accurate assessment of coastal habitat degradation is the essential prerequisite for coastal zone protection. In this study, an integrated framework of coastal habitat degradation assessment including landuse classification, habitat classifying and zoning, evaluation criterion of coastal habitat degradation and coastal habitat degradation index has been established for better regional coastal habitat assessment. Through establishment of detailed three-class landuse classification, the fine landscape change is revealed, the evaluation criterion of coastal habitat degradation through internal comparison based on the results of habitat classifying and zoning could indicate the levels of habitat degradation and distinguish the intensity of human disturbances in different habitat subareas under the same habitat classification. Finally, the results of coastal habitat degradation assessment could be achieved through coastal habitat degradation index (CHI). A case study of the framework is carried out in the Circum-Bohai-Sea-Coast, China, and the main results show the following: (1) The accuracy of all land use classes are above 90%, which indicates a satisfactory accuracy for the classification map. (2) The Circum-Bohai-Sea-Coast is divided into 3 kinds of habitats and 5 subareas. (3) In the five subareas of the Circum-Bohai-Sea-Coast, the levels of coastal habitat degradation own significant difference. The whole Circum-Bohai-Sea-Coast generally is in a worse state according to area weighting of each habitat subarea. This assessment framework of coastal habitat degradation would characterize the landuse change trend, realize better coastal habitat degradation assessment, reveal the habitat conservation tendency and distinguish intensity of human disturbances. Furthermore, it would support for accurate coastal

Bioclimatic predictions of habitat suitability for the biofuel switchgrass in North America under current and future climate scenarios

International Nuclear Information System (INIS)

Barney, Jacob N.; DiTomaso, Joseph M.

2010-01-01

Dedicated biofuel crops, while providing economic and other benefits, may adversely impact biodiversity directly via land use conversion, or indirectly via creation of novel invasive species. To mitigate negative impacts bioclimatic envelope models (BEM) can be used to estimate the potential distribution and suitable habitat based on the climate and distribution in the native range. We used CLIMEX to evaluate the regions of North America suitable for agronomic production, as well as regions potentially susceptible to an invasion of switchgrass (Panicum virgatum) under both current and future climate scenarios. Model results show that >8.7 million km 2 of North America has suitable to very favorable habitat, most of which occurs east of the Rocky Mountains. The non-native range of western North America is largely unsuitable to switchgrass as a crop or potential weed unless irrigation or permanent water is available. Under both the CGCM2 and HadCM3 climate models and A2 and B2 emissions scenarios, an overall increase in suitable habitat is predicted over the coming century, although the western US remains unsuitable. Our results suggest that much of North America is suitable for switchgrass cultivation, although this is likely to shift north in the coming century. Our results also agree with field collections of switchgrass outside its native range, which indicate that switchgrass is unlikely to establish unless it has access to water throughout the year (e.g., along a stream). Thus, it is the potential invasion of switchgrass into riparian habitats in the West that requires further investigation. (author)

Assessing juvenile salmon rearing habitat and associated predation risk in a lower Snake River reservoir

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Tiffan, Kenneth F.; Hatten, James R.; Trachtenbarg, David A

2015-01-01

Subyearling fall Chinook salmon (Oncorhynchus tshawytscha) in the Columbia River basin exhibit a transient rearing strategy and depend on connected shoreline habitats during freshwater rearing. Impoundment has greatly reduced the amount of shallow-water rearing habitat that is exacerbated by the steep topography of reservoirs. Periodic dredging creates opportunities to strategically place spoils to increase the amount of shallow-water habitat for subyearlings while at the same time reducing the amount of unsuitable area that is often preferred by predators. We assessed the amount and spatial arrangement of subyearling rearing habitat in Lower Granite Reservoir on the Snake River to guide future habitat improvement efforts. A spatially explicit habitat assessment was conducted using physical habitat data, two-dimensional hydrodynamic modelling and a statistical habitat model in a geographic information system framework. We used field collections of subyearlings and a common predator [smallmouth bass (Micropterus dolomieu)] to draw inferences about predation risk within specific habitat types. Most of the high-probability rearing habitat was located in the upper half of the reservoir where gently sloping landforms created low lateral bed slopes and shallow-water habitats. Only 29% of shorelines were predicted to be suitable (probability >0.5) for subyearlings, and the occurrence of these shorelines decreased in a downstream direction. The remaining, less suitable areas were composed of low-probability habitats in unmodified (25%) and riprapped shorelines (46%). As expected, most subyearlings were found in high-probability habitat, while most smallmouth bass were found in low-probability locations. However, some subyearlings were found in low-probability habitats, such as riprap, where predation risk could be high. Given their transient rearing strategy and dependence on shoreline habitats, subyearlings could benefit from habitat creation efforts in the lower

Present habitat suitability for Anopheles atroparvus (Diptera, Culicidae and its coincidence with former malaria areas in mainland Portugal

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César Capinha

2009-05-01

Full Text Available Malaria was a major health problem in the first half of the 20th Century in mainland Portugal. Nowadays, although the disease is no longer endemic, there is still the risk of future endemic infections due to the continuous occurrence of imported cases and the possibility of transmission in the country by Anopheles atroparvus Van Thiel, 1927. Since vector abundance constitute one of the foremost factors in malaria transmission, we have created several habitat suitability models to describe this vector species’ current distribution. Three different correlative models; namely (i a multilayer perceptron artificial neural network (MLP-ANN; (ii binary logistic regression (BLR; and (iii Mahalanobis distance were used to combine the species records with a set of five environmental predictors. Kappa coefficient values from k-fold cross-validation records showed that binary logistic regression produced the best predictions, while the other two models also produced acceptable results. Therefore, in order to reduce uncertainty, the three suitability models were combined. The resulting model identified high suitability for An. atroparvus in the majority of the country with exception of the northern and central coastal areas. Malaria distribution during the last endemic period in the country was also compared with the combined suitability model, and a high degree of spatial agreement was obtained (kappa = 0.62. It was concluded that habitat suitability for malaria vectors can constitute valuable information on the assessment of several spatial attributes of the disease. In addition, the results suggest that the spatial distribution of An. atroparvus in the country remains very similar to the one known about seven decades ago.

Assessing Impacts of Hydropower Regulation on Salmonid Habitat Connectivity to Guide River Restoration

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Buddendorf, Bas; Geris, Josie; Malcolm, Iain; Wilkinson, Mark; Soulsby, Chris

2016-04-01

Anthropogenic activity in riverine ecosystems has led to a substantial divergence from the natural state of many rivers globally. Many of Scotland's rivers have been regulated for hydropower with increasing intensity since the 1890s. At the same time they sustain substantial populations of Atlantic Salmon (Salmo salar L.), which have a range of requirements in terms of flow and access to habitat, depending on the different life-stages. River barriers for hydropower regulation can change the spatial and temporal connectivity within river networks, the impacts of which on salmon habitat are not fully understood. Insight into such changes in connectivity, and the link with the distribution and accessibility of suitable habitat and areas of high productivity, are essential to aid restoration and/or conservation efforts. This is because they indicate where such efforts might have a higher chance of being successful in terms of providing suitable habitat and increasing river productivity. In this study we applied a graph theory approach to assess historic (natural) and contemporary (regulated) in-stream habitat connectivity of the River Lyon, an important UK salmon river that is moderately regulated for hydropower. Historic maps and GIS techniques were used to construct the two contrasting river networks (i.e., natural vs. regulated). Subsequently, connectivity metrics were used to assess the impacts of hydropower infrastructure on upstream and downstream migration possibilities for adults and juveniles, respectively. A national juvenile salmon production model was used to weight the importance of reaches for juvenile salmon production. Results indicate that the impact of barriers in the Lyon on the connectivity indices depends on the type of barrier and its location within the network, but is generally low for both adults and juveniles, and that compared to the historic river network the reduction in the amount of suitable habitat and juvenile production is most marked

Wildlife Habitats Suitability Modelling using Fuzzy Inference System: A Case Study of Persian Leopard (Panthera pardus saxicolor in Shimbar Protected Area

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Z. Obeidavi

2017-06-01

Full Text Available Several modelling techniques have been developed for habitat suitability modelling. In the meantime, the Fuzzy Inference System (FIS with ability to model uncertainty of input variables is an effective method to model wildlife species habitat suitability. So, Persian Leopard habitat suitability was predicted in Shimbar Protected Area using FIS. Therefore, the effective environmental variables were determined. We also defined and determined the linguistic variables, linguistic values, and range of them. Then, we designed the membership functions of the fuzzy sets of the input and output variables. Also, the definition of the fuzzy rules in the system was performed. Finally, the defuzzification of output was carried out. The accuracy of the predictive model was tested using AUC. Also, 11 FISs were developed to determine sensitivity of the models and important variables in modelling. The results showed that the predictive model was more efficient than the random model (AUC=0.960. In addition, the ‘distance to capra’ was the most important predictor. According to the success of FIS in Persian Leopard habitat suitability modelling, we suggest this method to improve and complete the existing spatial information of wildlife habitats in Iran, especially about regions and species that have been less studied.

Landscape Metrics to Assess Habitat Suitability for Conversation Bird Species in the Southeastern United States

National Research Council Canada - National Science Library

Dove, Linda

2001-01-01

.... The degree to which a given species is affected by habitat fragmentation is dependent on the complex interaction of the habitat requirements of the species and the shape, size, and makeup of the fragmented habitat...

Habitat suitability and ecological niches of different plankton functional types in the global ocean

Science.gov (United States)

Vogt, Meike; Brun, Philipp; Payne, Mark R.; O'Brien, Colleen J.; Bednaršek, Nina; Buitenhuis, Erik T.; Doney, Scott C.; Leblanc, Karine; Le Quéré, Corinne; Luo, Yawei; Moriarty, Róisín; O'Brien, Todd D.; Schiebel, Ralf; Swan, Chantal

2013-04-01

Marine plankton play a central role in the biogeochemical cycling of important elements such as carbon, nitrogen, and sulphur. While our knowledge about marine ecosystem structure and functioning is still scarce and episodic, several recent observational studies confirm that marine ecosystems have been changing due to recent climate change, overfishing, and coastal eutrophication. In order to better understand marine ecosystem dynamics, the MAREDAT initiative has recently collected abundance and biomass data for 5 autotrophic (diatoms, Phaeocystis, coccolithophores, nitrogen fixers, picophytoplankton), and 6 heterotrophic plankton functional types (PFTs; bacteria, micro-, meso- and macrozooplankton, foraminifera and pteropods). Species distribution models (SDMs) are statistical tools that can be used to derive information about species habitats in space and time. They have been used extensively for a wide range of ecological applications in terrestrial ecosystems, but here we present the first global application in the marine realm, which was made possible by the MAREDAT data synthesis effort. We use a maximum entropy SDM to simulate global habitat suitability, habitat extent and ecological niches for different PFTs in the modern ocean. Present habitat suitability is derived from presence-only MAREDAT data and the observed annual and monthly mean levels of physiologically relevant variables such as SST, nutrient concentration or photosynthetic active radiation received in the mixed layer. This information can then be used to derive ecological niches for different species or taxa within each PFT, and to compare the ecological niches of different PFTs. While these results still need verification because data was not available for all ocean regions for all PFTs, they can give a first indication what present and future plankton habitats may look like, and what consequences we may have to expect for future marine ecosystem functioning and service provision in a warmer

Variability of Suitable Habitat of Western Winter-Spring Cohort for Neon Flying Squid in the Northwest Pacific under Anomalous Environments.

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Wei Yu

Full Text Available We developed a habitat suitability index (HSI model to evaluate the variability of suitable habitat for neon flying squid (Ommastrephes bartramii under anomalous environments in the Northwest Pacific Ocean. Commercial fisheries data from the Chinese squid-jigging vessels on the traditional fishing ground bounded by 35°-45°N and 150°-175°E from July to November during 1998-2009 were used for analyses, as well as the environmental variables including sea surface temperature (SST, chlorophyll-a (Chl-a concentration, sea surface height anomaly (SSHA and sea surface salinity (SSS. Two empirical HSI models (arithmetic mean model, AMM; geometric mean model, GMM were established according to the frequency distribution of fishing efforts. The AMM model was found to perform better than the GMM model. The AMM-based HSI model was further validated by the fishery and environmental data in 2010. The predicted HSI values in 1998 (high catch, 2008 (average catch and 2009 (low catch indicated that the squid habitat quality was strongly associated with the ENSO-induced variability in the oceanic conditions on the fishing ground. The La Niña events in 1998 tended to yield warm SST and favorable range of Chl-a concentration and SSHA, resulting in high-quality habitats for O. bartramii. While the fishing ground in the El Niño year of 2009 experienced anomalous cool waters and unfavorable range of Chl-a concentration and SSHA, leading to relatively low-quality squid habitats. Our findings suggest that the La Niña event in 1998 tended to result in more favorable habitats for O. bartramii in the Northwest Pacific with the gravity centers of fishing efforts falling within the defined suitable habitat and yielding high squid catch; whereas the El Niño event in 2009 yielded less favorable habitat areas with the fishing effort distribution mismatching the suitable habitat and a dramatic decline of the catch of O. bartramii. This study might provide some potentially

Creating a Ruggedness Layer for Use in Habitat Suitability Modeling for Ikh Nart Nature Reserve, Mongolia

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Nanette Bragin

2013-12-01

Full Text Available Spatially-explicit wildlife habitat models are increasingly used to study optimal habitat for species of conservation focus. A ruggedness layer, that summarizes aspect and slope, provides a useful tool for analyses conducted in a Geographic Information System (GIS, such as developing a habitat suitability index model to measure species habitat use. Ruggedness layers prove especially useful in areas where topography represents a key habitat component. We created a ruggedness layer for the Ikh Nart Nature Reserve and surrounding areas in northern Dornogobi Aimag (province, Mongolia. Using a 90 m Shuttle Radar Topography Mission (SRTM digital elevation model (DEM and ArcGIS 10 spatial analyst, we created 9 categories for ruggedness. When combined with other thematic layers such as vegetation, the ruggedness layer becomes a powerful tool for analyzing habitat use by individual animals. The results of such analyses may inform decision makers in protected area planning and conservation of endangered species.

Coupling habitat suitability and ecosystem health with AEHRA to estimate E-flows under intensive human activities

Science.gov (United States)

Zhao, C. S.; Yang, S. T.; Zhang, H. T.; Liu, C. M.; Sun, Y.; Yang, Z. Y.; Zhang, Y.; Dong, B. E.; Lim, R. P.

2017-08-01

Sustaining adequate environmental flows (e-flows) is a key principle for maintaining river biodiversity and ecosystem health, and for supporting sustainable water resource management in basins under intensive human activities. But few methods could correctly relate river health to e-flows assessment at the catchment scale when they are applied to rivers highly impacted by human activities. An effective method is presented in this study to closely link river health to e-flows assessment for rivers at the catchment scale. Key fish species, as indicators of ecosystem health, were selected by using the foodweb model. A multi-species-based habitat suitability model (MHSI) was improved, and coupled with dominance of the key fish species as well as the Index of Biological Integrity (IBI) to enhance its accuracy in determining the fish-preferred key hydrologic habitat variables related to ecosystem health. Taking 5964 fish samples and concurrent hydrological habitat variables as the basis, the combination of key variables of flow-velocity and water-depth were determined and used to drive the Adapted Ecological Hydraulic Radius Approach (AEHRA) to study e-flows in a Chinese urban river impacted by intensive human activities. Results showed that upstream urbanization resulted in abnormal river-course geomorphology and consequently abnormal e-flows under intensive human activities. Selection of key species based on the foodweb and trophic levels of aquatic ecosystems can reflect a comprehensive requirement on e-flows of the whole aquatic ecosystem, which greatly increases its potential to be used as a guidance tool for rehabilitation of degraded ecosystems at large spatial scales. These findings have significant ramifications for catchment e-flows assessment under intensive human activities and for river ecohealth restoration in such rivers globally.

Relative effects of road risk, habitat suitability, and connectivity on wildlife roadkills: the case of tawny owls (Strix aluco).

Science.gov (United States)

Santos, Sara M; Lourenço, Rui; Mira, António; Beja, Pedro

2013-01-01

Despite its importance for reducing wildlife-vehicle collisions, there is still incomplete understanding of factors responsible for high road mortality. In particular, few empirical studies examined the idea that spatial variation in roadkills is influenced by a complex interplay between road-related factors, and species-specific habitat quality and landscape connectivity. In this study we addressed this issue, using a 7-year dataset of tawny owl (Strix aluco) roadkills recorded along 37 km of road in southern Portugal. We used a multi-species roadkill index as a surrogate of intrinsic road risk, and we used a Maxent distribution model to estimate habitat suitability. Landscape connectivity was estimated from least-cost paths between tawny owl territories, using habitat suitability as a resistance surface. We defined 10 alternative scenarios to compute connectivity, based on variation in potential movement patterns according to territory quality and dispersal distance thresholds. Hierarchical partitioning of a regression model indicated that independent variation in tawny owl roadkills was explained primarily by the roadkill index (70.5%) and, to a much lesser extent, by landscape connectivity (26.2%), while habitat suitability had minor effects (3.3%). Analysis of connectivity scenarios suggested that owl roadkills were primarily related to short range movements (habitat quality and landscape connectivity are globally high for the study species. Nevertheless, the study supported the view that functional connectivity should be incorporated whenever possible in roadkill models, as it may greatly increase their power to predict the location of roadkill hotspots.

Utilizing NASA Earth Observations to investigate habitat suitability of the Cape Vulture in the Western Cape Province of South Africa

Science.gov (United States)

Gray, D.; Estes, M. G., Jr.; Griffin, R.; Estes, S. M.

2017-12-01

As the global urban population rapidly increases, many wild species lose habitat to human development. The Western Cape of South Africa contains one of Earth's 35 biodiversity hotspots, with remarkably high levels of species richness and endemism. Understanding the relationship between anthropogenic changes and key species in this region is crucial for conservation of its threatened ecosystems. The objective of this research was to investigate the effect that climate change and urbanization each have on habitat suitability of the Cape Vulture. This research utilized NASA satellite data and crowdsourced species sightings to model past, current, and future habitat suitability for this key species in the Western Cape. Data used from NASA Earth Observations included: Landsat 8- derived Land Cover, Modis Land Surface Temperature, Digital Elevation Models from the Shuttle Radar Topography Mission, and precipitation data which integrated in-situ stations with Infrared data. Species observations were sourced from the Global Biodiversity Information Facility online database. A geospatial modelling framework was used to generate maps of present, past and future suitable habitats for analysis and comparison. Changes in precipitation and temperature may be a factor in the extreme loss of habitat since 1995, and predict even more drastic loss in the future. This research provides insights on anthropogenic effects on a species' range which may be used to inform discussions of conservation as an element of environmentally sustainable development.

Assessing the Effects of Water Right Purchases on Stream Temperatures and Fish Habitat

Science.gov (United States)

Elmore, L.; Null, S. E.

2012-12-01

Warm stream temperature and low flow conditions are limiting factors for native trout species in Nevada's Walker River. Water rights purchases are being considered to increase instream flow and improve habitat conditions. However, the effect of water rights purchases on stream temperatures and fish habitat have yet to be assessed. Manipulating flow conditions affect stream temperatures by altering water depth, velocity, and thermal mass. This study uses the River Modeling System (RMSv4), an hourly, physically-based hydrodynamic and water quality model, to estimate flows and stream temperatures in the Walker River. The model is developed for two wet years (2010-2011). Study results highlight reaches with cold-water habitat that is suitable for native trout species. Previous research on the Walker River has evaluated instream flow changes with water rights purchases. This study incorporates stream temperatures as a proxy for trout habitat, and thus explicitly incorporates water quality and fish habitat into decision-making regarding water rights purchases. Walker River

Future habitat suitability for coral reef ecosystems under global warming and ocean acidification

OpenAIRE

Couce, Elena M; Ridgwell, Andy J; Hendy, Erica

2013-01-01

Rising atmospheric CO2 concentrations are placing spatially divergent stresses on the world’s tropical coral reefs through increasing ocean surface temperatures and ocean acidification. We show how these two stressors combine to alter the global habitat suitability for shallow coral reef ecosystems, using statistical Bioclimatic Envelope Models rather than basing projections on any a priori assumptions of physiological tolerances or fixed thresholds. We apply two different modeling approaches...

Using population viability analysis, genomics, and habitat suitability to forecast future population patterns of Little Owl Athene noctua across Europe.

Science.gov (United States)

Andersen, Line Holm; Sunde, Peter; Pellegrino, Irene; Loeschcke, Volker; Pertoldi, Cino

2017-12-01

The agricultural scene has changed over the past decades, resulting in a declining population trend in many species. It is therefore important to determine the factors that the individual species depend on in order to understand their decline. The landscape changes have also resulted in habitat fragmentation, turning once continuous populations into metapopulations. It is thus increasingly important to estimate both the number of individuals it takes to create a genetically viable population and the population trend. Here, population viability analysis and habitat suitability modeling were used to estimate population viability and future prospects across Europe of the Little Owl Athene noctua , a widespread species associated with agricultural landscapes. The results show a high risk of population declines over the coming 100 years, especially toward the north of Europe, whereas populations toward the southeastern part of Europe have a greater probability of persistence. In order to be considered genetically viable, individual populations must count 1,000-30,000 individuals. As Little Owl populations of several countries count <30,000, and many isolated populations in northern Europe count <1,000 individuals, management actions resulting in exchange of individuals between populations or even countries are probably necessary to prevent losing <1% genetic diversity over a 100-year period. At a continental scale, a habitat suitability analysis suggested Little Owl to be affected positively by increasing temperatures and urban areas, whereas an increased tree cover, an increasing annual rainfall, grassland, and sparsely vegetated areas affect the presence of the owl negatively. However, the low predictive power of the habitat suitability model suggests that habitat suitability might be better explained at a smaller scale.

Assessing three fish species ecological status in Colorado River, Grand Canyon based on physical habitat and population models.

Science.gov (United States)

Yao, Weiwei; Chen, Yuansheng

2018-04-01

Colorado River is a unique ecosystem and provides important ecological services such as habitat for fish species as well as water power energy supplies. River management for this ecosystem requires assessment and decision support tools for fish which involves protecting, restoring as well as forecasting of future conditions. In this paper, a habitat and population model was developed and used to determine the levels of fish habitat suitability and population density in Colorado River between Lees Ferry and Lake Mead. The short term target fish populations are also predicted based on native fish recovery strategy. This model has been developed by combining hydrodynamics, heat transfer and sediment transport models with a habitat suitability index model and then coupling with habitat model into life stage population model. The fish were divided into four life stages according to the fish length. Three most abundant and typical native and non-native fish were selected as target species, which are rainbow trout (Oncorhynchus mykiss), brown trout (Salmo trutta) and flannelmouth sucker (Catostomus latipinnis). Flow velocity, water depth, water temperature and substrates were used as the suitability indicators in habitat model and overall suitability index (OSI) as well as weight usable area (WUA) was used as an indicator in population model. A comparison was made between simulated fish population alteration and surveyed fish number fluctuation during 2000 to 2009. The application of this habitat and population model indicates that this model can be accurate present habitat situation and targets fish population dynamics of in the study areas. The analysis also indicates the flannelmouth sucker population will steadily increase while the rainbow trout will decrease based on the native fish recovery scheme. Copyright © 2018. Published by Elsevier Inc.

Invasion establishment and habitat suitability of Chromolaena odorata (L. King and Robinson over time and space in the western Himalayan forests of India

Directory of Open Access Journals (Sweden)

Gautam Mandal

2014-12-01

Full Text Available Habitat suitability assessment of the invasive species Chromolaena odorata (L. King and Robinson from Himalayan forests reveals some interesting findings and conclusions. At different study sites, 29 of 72 species were exotic and invasive and comprised 21 genera and eight families. Indigenous species accounted for 59% of the total species and comprised 26 genera and 11 families. Perennials outnumbered the annuals in all study sites. Chromolaena odorata and Lantana camara L. were the only invasive species that were common to all sites with high importance value index values. The present work reveals that sites with high biotic pressure, maximum temperature variation, open forest canopy, and free from herbivory are the most suitable habitat for the growth of C. odorata. An elevated level of phosphorus, potassium, magnesium, soil organic matter, and nitrogen and acidic soil in all invaded sites are possible reasons for further invasion of C. odorata.

Using habitat suitability models to target invasive plant species surveys.

Science.gov (United States)

Crall, Alycia W; Jarnevich, Catherine S; Panke, Brendon; Young, Nick; Renz, Mark; Morisette, Jeffrey

2013-01-01

Managers need new tools for detecting the movement and spread of nonnative, invasive species. Habitat suitability models are a popular tool for mapping the potential distribution of current invaders, but the ability of these models to prioritize monitoring efforts has not been tested in the field. We tested the utility of an iterative sampling design (i.e., models based on field observations used to guide subsequent field data collection to improve the model), hypothesizing that model performance would increase when new data were gathered from targeted sampling using criteria based on the initial model results. We also tested the ability of habitat suitability models to predict the spread of invasive species, hypothesizing that models would accurately predict occurrences in the field, and that the use of targeted sampling would detect more species with less sampling effort than a nontargeted approach. We tested these hypotheses on two species at the state scale (Centaurea stoebe and Pastinaca sativa) in Wisconsin (USA), and one genus at the regional scale (Tamarix) in the western United States. These initial data were merged with environmental data at 30-m2 resolution for Wisconsin and 1-km2 resolution for the western United States to produce our first iteration models. We stratified these initial models to target field sampling and compared our models and success at detecting our species of interest to other surveys being conducted during the same field season (i.e., nontargeted sampling). Although more data did not always improve our models based on correct classification rate (CCR), sensitivity, specificity, kappa, or area under the curve (AUC), our models generated from targeted sampling data always performed better than models generated from nontargeted data. For Wisconsin species, the model described actual locations in the field fairly well (kappa = 0.51, 0.19, P guiding invasive species monitoring, and we support the use of an iterative sampling design for

Assessing Potential Habitat and Carrying Capacity for Reintroduction of Plains Bison (Bison bison bison in Banff National Park.

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Robin Steenweg

Full Text Available Interest in bison (Bison bison, B. bonasus conservation and restoration continues to grow globally. In Canada, plains bison (B. b. bison are threatened, occupying less than 0.5% of their former range. The largest threat to their recovery is the lack of habitat in which they are considered compatible with current land uses. Fences and direct management make range expansion by most bison impossible. Reintroduction of bison into previously occupied areas that remain suitable, therefore, is critical for bison recovery in North America. Banff National Park is recognized as historical range of plains bison and has been identified as a potential site for reintroduction of a wild population. To evaluate habitat quality and assess if there is sufficient habitat for a breeding population, we developed a Habitat Suitability Index (HSI model for the proposed reintroduction and surrounding areas in Banff National Park (Banff. We then synthesize previous studies on habitat relationships, forage availability, bison energetics and snowfall scenarios to estimate nutritional carrying capacity. Considering constraints on nutritional carrying capacity, the most realistic scenario that we evaluated resulted in an estimated maximum bison density of 0.48 bison/km2. This corresponds to sufficient habitat to support at least 600 to 1000 plains bison, which could be one of the largest 10 plains bison populations in North America. Within Banff, there is spatial variation in predicted bison habitat suitability and population size that suggests one potential reintroduction site as the most likely to be successful from a habitat perspective. The successful reintroduction of bison into Banff would represent a significant global step towards conserving this iconic species, and our approach provides a useful template for evaluating potential habitat for other endangered species reintroductions into their former range.

Spatial transferability of habitat suitability models of Nephrops norvegicus among fished areas in the Northeast Atlantic: sufficiently stable for marine resource conservation?

Directory of Open Access Journals (Sweden)

Valentina Lauria

Full Text Available Knowledge of the spatial distribution and habitat associations of species in relation to the environment is essential for their management and conservation. Habitat suitability models are useful in quantifying species-environment relationships and predicting species distribution patterns. Little is known, however, about the stability and performance of habitat suitability models when projected into new areas (spatial transferability and how this can inform resource management. The aims of this study were to model habitat suitability of Norway lobster (Nephrops norvegicus in five fished areas of the Northeast Atlantic (Aran ground, Irish Sea, Celtic Sea, Scotland Inshore and Fladen ground, and to test for spatial transferability of habitat models among multiple regions. Nephrops burrow density was modelled using generalised additive models (GAMs with predictors selected from four environmental variables (depth, slope, sediment and rugosity. Models were evaluated and tested for spatial transferability among areas. The optimum models (lowest AICc for different areas always included depth and sediment as predictors. Burrow densities were generally greater at depth and in finer sediments, but relationships for individual areas were sometimes more complex. Aside from an inclusion of depth and sediment, the optimum models differed between fished areas. When it came to tests of spatial transferability, however, most of the models were able to predict Nephrops density in other areas. Furthermore, transferability was not dependent on use of the optimum models since competing models were also able to achieve a similar level of transferability to new areas. A degree of decoupling between model 'fitting' performance and spatial transferability supports the use of simpler models when extrapolating habitat suitability maps to different areas. Differences in the form and performance of models from different areas may supply further information on the processes

Increase in quantity and quality of suitable areas for invasive species as climate changes.

Science.gov (United States)

Bertelsmeier, Cleo; Luque, Gloria M; Courchamp, Franck

2013-12-01

As climatically suitable range projections become increasingly used to assess distributions of species, we recommend systematic assessments of the quality of habitat in addition to the classical binary classification of habitat. We devised a method to assess occurrence probability, captured by a climatic suitability index, through which we could determine variations in the quality of potential habitat. This relative risk assessment circumvents the use of an arbitrary suitability threshold. We illustrated our method with 2 case studies on invasive ant species. We estimated invasion potential of the destroyer ant (Monomorium destructor) and the European fire ant (Myrmica rubra) on a global scale currently and by 2080 with climate change. We found that 21.1% of the world's landmass currently has a suitable climate for the destroyer ant and 16% has a suitable climate for European fire ant. Our climatic suitability index showed that both ant species would benefit from climate change, but in different ways. The size of the potential distribution increased by 35.8% for the destroyer ant. Meanwhile, the total area of potential distribution remained the same for the European fire ant (>0.05%), but the level of climatic suitability within this range increased greatly and led to an improvement in habitat quality (i.e., of invasive species' establishment likelihood). Either through quantity or quality of suitable areas, both invasive ant species are likely to increase the extent of their invasion in the future, following global climate change. Our results show that species may increase their range if either more areas become suitable or if the available areas present improved suitability. Studies in which an arbitrary suitability threshold was used may overlook changes in area quality within climatically suitable areas and as a result reach incorrect predictions. Incremento de la Cantidad y Calidad de Áreas Idóneas para Especies Invasoras a Medida que Cambia el Clima. �

Sage-grouse habitat selection during winter in Alberta

Science.gov (United States)

Carpenter, Jennifer L.; Aldridge, Cameron L.; Boyce, Mark S.

2010-01-01

Greater sage-grouse (Centrocercus urophasianus) are dependent on sagebrush (Artemisia spp.) for food and shelter during winter, yet few studies have assessed winter habitat selection, particularly at scales applicable to conservation planning. Small changes to availability of winter habitats have caused drastic reductions in some sage-grouse populations. We modeled winter habitat selection by sage-grouse in Alberta, Canada, by using a resource selection function. Our purpose was to 1) generate a robust winter habitat-selection model for Alberta sage-grouse; 2) spatially depict habitat suitability in a Geographic Information System to identify areas with a high probability of selection and thus, conservation importance; and 3) assess the relative influence of human development, including oil and gas wells, in landscape models of winter habitat selection. Terrain and vegetation characteristics, sagebrush cover, anthropogenic landscape features, and energy development were important in top Akaike's Information Criterionselected models. During winter, sage-grouse selected dense sagebrush cover and homogenous less rugged areas, and avoided energy development and 2-track truck trails. Sage-grouse avoidance of energy development highlights the need for comprehensive management strategies that maintain suitable habitats across all seasons. ?? 2010 The Wildlife Society.

Upward Altitudinal Shifts in Habitat Suitability of Mountain Vipers since the Last Glacial Maximum.

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Masoud Yousefi

Full Text Available We determined the effects of past and future climate changes on the distribution of the Montivipera raddei species complex (MRC that contains rare and endangered viper species limited to Iran, Turkey and Armenia. We also investigated the current distribution of MRC to locate unidentified isolated populations as well as to evaluate the effectiveness of the current network of protected areas for their conservation. Present distribution of MRC was modeled based on ecological variables and model performance was evaluated by field visits. Some individuals at the newly identified populations showed uncommon morphological characteristics. The distribution map of MRC derived through modeling was then compared with the distribution of protected areas in the region. We estimated the effectiveness of the current protected area network to be 10%, which would be sufficient for conserving this group of species, provided adequate management policies and practices are employed. We further modeled the distribution of MRC in the past (21,000 years ago and under two scenarios in the future (to 2070. These models indicated that climatic changes probably have been responsible for an upward shift in suitable habitats of MRC since the Last Glacial Maximum, leading to isolation of allopatric populations. Distribution will probably become much more restricted in the future as a result of the current rate of global warming. We conclude that climate change most likely played a major role in determining the distribution pattern of MRC, restricting allopatric populations to mountaintops due to habitat alterations. This long-term isolation has facilitated unique local adaptations among MRC populations, which requires further investigation. The suitable habitat patches identified through modeling constitute optimized solutions for inclusion in the network of protected areas in the region.

Habitat quality assessment for the Eurasian otter (Lutra lutra on the river Jajrood, Iran

Directory of Open Access Journals (Sweden)

Roohallah Mirzaei

2010-06-01

Full Text Available Abstract There is little information about the status and ecology of the Eurasian otter (Lutra lutra in Iran. We assessed the habitat suitability for otters of the River Jajrood, Tehran province, measuring, or visually estimating, 12 environmental parameters along 16 600 m long river stretches (sampling sites. The downstream stretches of the river were found to be more suitable for otters with respect to the upper part of its course. Although the assessments of habitat suitability for the otter may be affected by several limits, the current distribution of the species on the river agrees with the results of this study. The preservation of the otter in Tehran province should involve the restoration of the ecosystem of the River Jajrood in order to improve the length of suitable river stretches.
Riassunto Stima dell’idoneità ambientale per la lontra (Lutra lutra del fiume Jajrood, Iran. Le informazioni relative alla lontra (Lutra lutra in Iran sono scarse. L’idoneità ambientale per la specie del fiume Jajrood, provincia di Tehran, è stata valutata, misurando o stimando 12 parametri ambientali lungo 16 stazioni di campionamento, coincidenti con tratti di fiume della lunghezza di 600 m. I tratti più a valle sono risultati più idonei rispetto al corso superiore del fiume. Malgrado i numerosi limiti del metodo di stima dell’idoneità ambientale adottato, i risultati sono in accordo con l’attuale distribuzione della lontra lungo il fiume Jajrood. La conservazione della lontra nella provincia di Tehran dovrebbe prevedere miglioramenti ambientali volti a incrementare lo sviluppo lineare degli habitat idonei lungo il fiume Jajrood.

doi:10.4404/hystrix-20.2-4447

Impact of Alternative Environmental Flow Prescriptions on Hydropower Production and Fish Habitat Suitability

Science.gov (United States)

Castellarin, A.; Ceola, S.; Pugliese, A.; Galeati, G. A.

2015-12-01

Anthropogenic activities along streams and rivers are increasingly recognized to be a major concern for fluvial ecosystems. The management of water resources, by means of e.g. flow diversions and dams, for industrial, agricultural, water-supply, hydropower production and flood protection purposes induces significant changes to the natural streamflow regime of a river. Indeed, the river flow regime is known to be a major abiotic factor influencing fluvial ecosystems. An established approach aimed at preserving the behaviour and distribution of fluvial species relies on the definition of minimum streamflow requirements (i.e., environmental flows) downstream of dams and diversion structures. Such environmental flows are normally identified through methodologies that have an empirical nature and may not be representative of local ecological and hydraulic conditions. While the effect of imposing a minimum discharge release is easily predictable in terms of e.g. loss of hydropower production, the advantages in terms of species preferences are often poorly understood and seldom assessed. To analyze the interactions between flow releases and the behaviour and distribution of fluvial species (i.e., from periphyton, to benthic invertebrate and fish), one may use a habitat suitability curve, which is a fundamental tool capable of describing species preferences influenced by any generic environmental variable. The outcomes of a real case study applied to several Italian rivers, located in the Marche administrative district in Central Italy (∽10000km2), in which we quantitatively assess the effects of alternative environmental flow scenarios on the existing hydropower network and on two fish species that are quite abundant in the study area (i.e., Leuciscus cephalus cabeda and Barbus barbus plebejus), will be presented and discussed. The proposed analysis, which can be easily adapted to different riparian habitats and hydrological contexts, is a useful tool to guide the

Deep-Sea Soft Coral Habitat Suitability

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Deep-sea corals, also known as cold water corals, create complex communities that provide habitat for a variety of invertebrate and fish species, such as grouper,...

Deep-Sea Stony Coral Habitat Suitability

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Deep-sea corals, also known as cold water corals, create complex communities that provide habitat for a variety of invertebrate and fish species, such as grouper,...

Fish habitat simulation models and integrated assessment tools

International Nuclear Information System (INIS)

Harby, A.; Alfredsen, K.

1999-01-01

Because of human development water use increases in importance, and this worldwide trend is leading to an increasing number of user conflicts with a strong need for assessment tools to measure the impacts both on the ecosystem and the different users and user groups. The quantitative tools must allow a comparison of alternatives, different user groups, etc., and the tools must be integrated while impact assessments includes different disciplines. Fish species, especially young ones, are indicators of the environmental state of a riverine system and monitoring them is a way to follow environmental changes. The direct and indirect impacts on the ecosystem itself are measured, and impacts on user groups is not included. Fish habitat simulation models are concentrated on, and methods and examples are considered from Norway. Some ideas on integrated modelling tools for impact assessment studies are included. One dimensional hydraulic models are rapidly calibrated and do not require any expert knowledge in hydraulics. Two and three dimensional models require a bit more skilled users, especially if the topography is very heterogeneous. The advantages of using two and three dimensional models include: they do not need any calibration, just validation; they are predictive; and they can be more cost effective than traditional habitat hydraulic models when combined with modern data acquisition systems and tailored in a multi-disciplinary study. Suitable modelling model choice should be based on available data and possible data acquisition, available manpower, computer, and software resources, and needed output and accuracy in the output. 58 refs

Predicted effects of future climate warming on thermal habitat suitability for Lake Sturgeon (Acipenser fulvescens, Rafinesque, 1817) in rivers in Wisconsin, USA

Science.gov (United States)

Lyons, John D.; Stewart, Jana S.

2015-01-01

The Lake Sturgeon (Acipenser fulvescens, Rafinesque, 1817) may be threatened by future climate warming. The purpose of this study was to identify river reaches in Wisconsin, USA, where they might be vulnerable to warming water temperatures. In Wisconsin, A. fulvescens is known from 2291 km of large-river habitat that has been fragmented into 48 discrete river-lake networks isolated by impassable dams. Although the exact temperature tolerances are uncertain, water temperatures above 28–30°C are potentially less suitable for this coolwater species. Predictions from 13 downscaled global climate models were input to a lotic water temperature model to estimate amounts of potential thermally less-suitable habitat at present and for 2046–2065. Currently, 341 km (14.9%) of the known habitat are estimated to regularly exceed 28°C for an entire day, but only 6 km (0.3%) to exceed 30°C. In 2046–2065, 685–2164 km (29.9–94.5%) are projected to exceed 28°C and 33–1056 km (1.4–46.1%) to exceed 30°C. Most river-lake networks have cooler segments, large tributaries, or lakes that might provide temporary escape from potentially less suitable temperatures, but 12 short networks in the Lower Fox and Middle Wisconsin rivers totaling 93.6 km are projected to have no potential thermal refugia. One possible adaptation to climate change could be to provide fish passage or translocation so that riverine Lake Sturgeon might have access to more thermally suitable habitats.

Effect of spatial and temporal scales on habitat suitability modeling: A case study of Ommastrephes bartramii in the northwest pacific ocean

Science.gov (United States)

Gong, Caixia; Chen, Xinjun; Gao, Feng; Tian, Siquan

2014-12-01

Temporal and spatial scales play important roles in fishery ecology, and an inappropriate spatio-temporal scale may result in large errors in modeling fish distribution. The objective of this study is to evaluate the roles of spatio-temporal scales in habitat suitability modeling, with the western stock of winter-spring cohort of neon flying squid ( Ommastrephes bartramii) in the northwest Pacific Ocean as an example. In this study, the fishery-dependent data from the Chinese Mainland Squid Jigging Technical Group and sea surface temperature (SST) from remote sensing during August to October of 2003-2008 were used. We evaluated the differences in a habitat suitability index model resulting from aggregating data with 36 different spatial scales with a combination of three latitude scales (0.5°, 1° and 2°), four longitude scales (0.5°, 1°, 2° and 4°), and three temporal scales (week, fortnight, and month). The coefficients of variation (CV) of the weekly, biweekly and monthly suitability index (SI) were compared to determine which temporal and spatial scales of SI model are more precise. This study shows that the optimal temporal and spatial scales with the lowest CV are month, and 0.5° latitude and 0.5° longitude for O. bartramii in the northwest Pacific Ocean. This suitability index model developed with an optimal scale can be cost-effective in improving forecasting fishing ground and requires no excessive sampling efforts. We suggest that the uncertainty associated with spatial and temporal scales used in data aggregations needs to be considered in habitat suitability modeling.

Defining geo-habitats for groundwater ecosystem assessments: an example from England and Wales (UK)

Science.gov (United States)

Weitowitz, Damiano C.; Maurice, Louise; Lewis, Melinda; Bloomfield, John P.; Reiss, Julia; Robertson, Anne L.

2017-12-01

Groundwater ecosystems comprising micro-organisms and metazoans provide an important contribution to global biodiversity. Their complexity depends on geology, which determines the physical habitat available, and the chemical conditions within it. Despite this, methods of classifying groundwater habitats using geological data are not well established and researchers have called for higher resolution habitat frameworks. A novel habitat typology for England and Wales (UK) is proposed, which distinguishes 11 geological habitats (geo-habitats) on hydrogeological principles and maps their distribution. Hydrogeological and hydrochemical data are used to determine the characteristics of each geo-habitat, and demonstrate their differences. Using these abiotic parameters, a new method to determine abiotic habitat quality is then developed. The geo-habitats had significantly different characteristics, validating the classification system. All geo-habitats were highly heterogeneous, containing both high quality habitat patches that are likely to be suitable for fauna, and areas of low quality that may limit faunal distributions. Karstic and porous habitats generally were higher quality than fractured habitats. Overall, 70% of England and Wales are covered by lower quality fractured habitats, with only 13% covered by higher quality habitats. The main areas of high quality habitats occur in central England as north-south trending belts, possibly facilitating dispersal along this axis. They are separated by low quality geo-habitats that may prevent east-west dispersal of fauna. In south-west England and Wales suitable geo-habitats occur as small isolated patches. Overall, this paper provides a new national-scale typology that is adaptable for studies in other geographic areas.

Modeling suitable habitat of invasive red lionfish Pterois volitans (Linnaeus, 1758) in North and South America’s coastal waters

Science.gov (United States)

Evangelista, Paul H.; Young, Nicholas E.; Schofield, Pamela J.; Jarnevich, Catherine S.

2016-01-01

We used two common correlative species-distribution models to predict suitable habitat of invasive red lionfish Pterois volitans (Linnaeus, 1758) in the western Atlantic and eastern Pacific Oceans. The Generalized Linear Model (GLM) and the Maximum Entropy (Maxent) model were applied using the Software for Assisted Habitat Modeling. We compared models developed using native occurrences, using non-native occurrences, and using both native and non-native occurrences. Models were trained using occurrence data collected before 2010 and evaluated with occurrence data collected from the invaded range during or after 2010. We considered a total of 22 marine environmental variables. Models built with non-native only or both native and non-native occurrence data outperformed those that used only native occurrences. Evaluation metrics based on the independent test data were highest for models that used both native and non-native occurrences. Bathymetry was the strongest environmental predictor for all models and showed increasing suitability as ocean floor depth decreased, with salinity ranking the second strongest predictor for models that used native and both native and non-native occurrences, indicating low habitat suitability for salinities lionfish could continue to invade southern latitudes in the western Atlantic Ocean and may establish localized populations in the eastern Pacific Ocean. We reiterate the importance in the choice of the training data source (native, non-native, or native/non-native) used to develop correlative species distribution models for invasive species.

Predicting freshwater habitat integrity using land-use surrogates

African Journals Online (AJOL)

2007-04-02

Apr 2, 2007 ... Quantification of potential surrogates of freshwater habitat integrity. We chose a series of land-use variables that might be suitable predictors for assessing freshwater habitat integrity from the land cover map (CSIR 2005) and added separate GIS surfaces for human population density and the distribution of ...

Deep-sea benthic megafaunal habitat suitability modelling: A global-scale maximum entropy model for xenophyophores

Science.gov (United States)

Ashford, Oliver S.; Davies, Andrew J.; Jones, Daniel O. B.

2014-12-01

Xenophyophores are a group of exclusively deep-sea agglutinating rhizarian protozoans, at least some of which are foraminifera. They are an important constituent of the deep-sea megafauna that are sometimes found in sufficient abundance to act as a significant source of habitat structure for meiofaunal and macrofaunal organisms. This study utilised maximum entropy modelling (Maxent) and a high-resolution environmental database to explore the environmental factors controlling the presence of Xenophyophorea and two frequently sampled xenophyophore species that are taxonomically stable: Syringammina fragilissima and Stannophyllum zonarium. These factors were also used to predict the global distribution of each taxon. Areas of high habitat suitability for xenophyophores were highlighted throughout the world's oceans, including in a large number of areas yet to be suitably sampled, but the Northeast and Southeast Atlantic Ocean, Gulf of Mexico and Caribbean Sea, the Red Sea and deep-water regions of the Malay Archipelago represented particular hotspots. The two species investigated showed more specific habitat requirements when compared to the model encompassing all xenophyophore records, perhaps in part due to the smaller number and relatively more clustered nature of the presence records available for modelling at present. The environmental variables depth, oxygen parameters, nitrate concentration, carbon-chemistry parameters and temperature were of greatest importance in determining xenophyophore distributions, but, somewhat surprisingly, hydrodynamic parameters were consistently shown to have low importance, possibly due to the paucity of well-resolved global hydrodynamic datasets. The results of this study (and others of a similar type) have the potential to guide further sample collection, environmental policy, and spatial planning of marine protected areas and industrial activities that impact the seafloor, particularly those that overlap with aggregations of

Predicting Effects of Climate Change on Habitat Suitability of Red Spruce (Picea rubens Sarg. in the Southern Appalachian Mountains of the USA: Understanding Complex Systems Mechanisms through Modeling

Directory of Open Access Journals (Sweden)

Kyung Ah Koo

2015-04-01

Full Text Available Alpine, subalpine and boreal tree species, of low genetic diversity and adapted to low optimal temperatures, are vulnerable to the warming effects of global climate change. The accurate prediction of these species’ distributions in response to climate change is critical for effective planning and management. The goal of this research is to predict climate change effects on the distribution of red spruce (Picea rubens Sarg. in the Great Smoky Mountains National Park (GSMNP, eastern USA. Climate change is, however, conflated with other environmental factors, making its assessment a complex systems problem in which indirect effects are significant in causality. Predictions were made by linking a tree growth simulation model, red spruce growth model (ARIM.SIM, to a GIS spatial model, red spruce habitat model (ARIM.HAB. ARIM.SIM quantifies direct and indirect interactions between red spruce and its growth factors, revealing the latter to be dominant. ARIM.HAB spatially distributes the ARIM.SIM simulations under the assumption that greater growth reflects higher probabilities of presence. ARIM.HAB predicts the future habitat suitability of red spruce based on growth predictions of ARIM.SIM under climate change and three air pollution scenarios: 10% increase, no change and 10% decrease. Results show that suitable habitats shrink most when air pollution increases. Higher temperatures cause losses of most low-elevation habitats. Increased precipitation and air pollution produce acid rain, which causes loss of both low- and high-elevation habitats. The general prediction is that climate change will cause contraction of red spruce habitats at both lower and higher elevations in GSMNP, and the effects will be exacerbated by increased air pollution. These predictions provide valuable information for understanding potential impacts of global climate change on the spatiotemporal distribution of red spruce habitats in GSMNP.

Global decline in suitable habitat for Angiostrongylus ( = Parastrongylus cantonensis: the role of climate change.

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Emily M York

Full Text Available Climate change is implicated in the alteration of the ranges of species worldwide. Such shifts in species distributions may introduce parasites/pathogens, hosts, and vectors associated with disease to new areas. The parasite Angiostrongylus ( = Parastrongylus cantonensis is an invasive species that causes eosinophilic meningitis in humans and neurological abnormalities in domestic/wild animals. Although native to southeastern Asia, A. cantonensis has now been reported from more than 30 countries worldwide. Given the health risks, it is important to describe areas with potentially favorable climate for the establishment of A. cantonensis, as well as areas where this pathogen might become established in the future. We used the program Maxent to develop an ecological niche model for A. cantonensis based on 86 localities obtained from published literature. We then modeled areas of potential A. cantonensis distribution as well as areas projected to have suitable climatic conditions under four Representative Concentration Pathways (RCP scenarios by the 2050s and the 2070s. The best model contained three bioclimatic variables: mean diurnal temperature range, minimum temperature of coldest month and precipitation of warmest quarter. Potentially suitable habitat for A. cantonensis was located worldwide in tropical and subtropical regions. Under all climate change RCP scenarios, the center of the projected distribution shifted away from the equator at a rate of 68-152 km per decade. However, the extent of areas with highly suitable habitat (>50% declined by 10.66-15.66% by the 2050s and 13.11-16.11% by the 2070s. These results conflict with previous studies, which have generally found that the prevalence of tropical pathogens will increase during the 21st century. Moreover, it is likely that A. cantonensis will continue to expand its current range in the near future due to introductions and host expansion, whereas climate change will reduce the total

Global decline in suitable habitat for Angiostrongylus ( = Parastrongylus) cantonensis: the role of climate change.

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York, Emily M; Butler, Christopher J; Lord, Wayne D

2014-01-01

Climate change is implicated in the alteration of the ranges of species worldwide. Such shifts in species distributions may introduce parasites/pathogens, hosts, and vectors associated with disease to new areas. The parasite Angiostrongylus ( = Parastrongylus) cantonensis is an invasive species that causes eosinophilic meningitis in humans and neurological abnormalities in domestic/wild animals. Although native to southeastern Asia, A. cantonensis has now been reported from more than 30 countries worldwide. Given the health risks, it is important to describe areas with potentially favorable climate for the establishment of A. cantonensis, as well as areas where this pathogen might become established in the future. We used the program Maxent to develop an ecological niche model for A. cantonensis based on 86 localities obtained from published literature. We then modeled areas of potential A. cantonensis distribution as well as areas projected to have suitable climatic conditions under four Representative Concentration Pathways (RCP) scenarios by the 2050s and the 2070s. The best model contained three bioclimatic variables: mean diurnal temperature range, minimum temperature of coldest month and precipitation of warmest quarter. Potentially suitable habitat for A. cantonensis was located worldwide in tropical and subtropical regions. Under all climate change RCP scenarios, the center of the projected distribution shifted away from the equator at a rate of 68-152 km per decade. However, the extent of areas with highly suitable habitat (>50%) declined by 10.66-15.66% by the 2050s and 13.11-16.11% by the 2070s. These results conflict with previous studies, which have generally found that the prevalence of tropical pathogens will increase during the 21st century. Moreover, it is likely that A. cantonensis will continue to expand its current range in the near future due to introductions and host expansion, whereas climate change will reduce the total geographic area of

Predicting Potential Changes in Suitable Habitat and Distribution by 2100 for Tree Species of the Eastern United States

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Louis R Iverson; Anantha M. Prasad; Mark W. Schwartz; Mark W. Schwartz

2005-01-01

We predict current distribution and abundance for tree species present in eastern North America, and subsequently estimate potential suitable habitat for those species under a changed climate with 2 x CO2. We used a series of statistical models (i.e., Regression Tree Analysis (RTA), Multivariate Adaptive Regression Splines (MARS), Bagging Trees (...

Niche suitability affects development: skull asymmetry increases in less suitable areas.

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Renan Maestri

Full Text Available For conservation purposes, it is important to take into account the suitability of a species to particular habitats; this information may predict the long-term survival of a species. In this sense, morphological measures of developmental stress, such as fluctuating asymmetry, can be proxies for an individual's performance in different regions. In this study, we conducted tests to determine whether areas with different levels of suitability for a species (generated by ecological niche models were congruent with morphological markers that reflect environmental stress and morphological variance. We generated a Maxent niche model and compared the suitability assessments of several areas with the skull morphology data (fluctuating asymmetry and morphological disparity of populations of the Atlantic forest endemic to Brazil rodent Akodon cursor. Our analyses showed a significant negative relationship between suitability levels and fluctuating asymmetry levels, which indicates that in less suitable areas, the individuals experience numerous disturbances during skull ontogeny. We have not found an association between morphological variance and environmental suitability. As expected, these results suggest that in environments with a lower suitability, developmental stress is increased. Such information is helpful in the understanding of the species evolution and in the selection of priority areas for the conservation of species.

Model output for deep-sea coral habitat suitability in the U.S. North and Mid-Atlantic from 2013 (NCEI Accession 0145923)

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National Oceanic and Atmospheric Administration, Department of Commerce — This dataset was created for potential use as an environmental predictor in spatial predictive models of deep-sea coral habitat suitability. Deep-sea corals are of...

Quantification of habitat fragmentation reveals extinction risk in terrestrial mammals

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Crooks, Kevin R.; Burdett, Christopher L.; Theobald, David M.; King, Sarah R. B.; Rondinini, Carlo; Boitani, Luigi

2017-01-01

Although habitat fragmentation is often assumed to be a primary driver of extinction, global patterns of fragmentation and its relationship to extinction risk have not been consistently quantified for any major animal taxon. We developed high-resolution habitat fragmentation models and used phylogenetic comparative methods to quantify the effects of habitat fragmentation on the world’s terrestrial mammals, including 4,018 species across 26 taxonomic Orders. Results demonstrate that species with more fragmentation are at greater risk of extinction, even after accounting for the effects of key macroecological predictors, such as body size and geographic range size. Species with higher fragmentation had smaller ranges and a lower proportion of high-suitability habitat within their range, and most high-suitability habitat occurred outside of protected areas, further elevating extinction risk. Our models provide a quantitative evaluation of extinction risk assessments for species, allow for identification of emerging threats in species not classified as threatened, and provide maps of global hotspots of fragmentation for the world’s terrestrial mammals. Quantification of habitat fragmentation will help guide threat assessment and strategic priorities for global mammal conservation. PMID:28673992

Habitat suitability criteria via parametric distributions: estimation, model selection and uncertainty

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Som, Nicholas A.; Goodman, Damon H.; Perry, Russell W.; Hardy, Thomas B.

2016-01-01

Previous methods for constructing univariate habitat suitability criteria (HSC) curves have ranged from professional judgement to kernel-smoothed density functions or combinations thereof. We present a new method of generating HSC curves that applies probability density functions as the mathematical representation of the curves. Compared with previous approaches, benefits of our method include (1) estimation of probability density function parameters directly from raw data, (2) quantitative methods for selecting among several candidate probability density functions, and (3) concise methods for expressing estimation uncertainty in the HSC curves. We demonstrate our method with a thorough example using data collected on the depth of water used by juvenile Chinook salmon (Oncorhynchus tschawytscha) in the Klamath River of northern California and southern Oregon. All R code needed to implement our example is provided in the appendix. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

Spatial modelling of Lutzomyia (Nyssomyia whitmani s.l. (Antunes & Coutinho, 1939 (Diptera: Psychodidae: Phlebotominae habitat suitability in the state of Mato Grosso, Brazil

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Peter Zeilhofer

2008-11-01

Full Text Available Lutzomyia (Nyssomyia whitmani s.l.is the main vector of cutaneous leishmaniasis in state of Mato Grosso, but little is known about environmental determinants of its spatial distribution on a regional scale. Entomologic surveys of this sand fly species, conducted between 1996 and 2001 in 41 state municipalities, were used to investigate the relationships between environmental factors and the presence of the species, and to develop a spatial model of habitat suitability. The relationship between averaged CDC light trap indexes and 15 environmental and socio-economic factors were tested by logistic regression (LR analysis. Spatial layers of deforestation tax and the Brazilian index of gross net production (IGNP were identified as significant explanatory variables for vector presence in the LR model, and these were then overlaid with habitat maps. The highest habitat suitability in 2001 was obtained for the heavily deforested areas in the Central-North, South, East, and Southwest of Mato Grosso, particularly in municipalities with lower IGNP values.

Mapping snags and understory shrubs for LiDAR based assessment of wildlife habitat suitability

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Sebastian Martinuzzi; Lee A. Vierling; William A. Gould; Michael J. Falkowski; Jeffrey S. Evans; Andrew T. Hudak; Kerri T. Vierling

2009-01-01

The lack of maps depicting forest three-dimensional structure, particularly as pertaining to snags and understory shrub species distribution, is a major limitation for managing wildlife habitat in forests. Developing new techniques to remotely map snags and understory shrubs is therefore an important need. To address this, we first evaluated the use of LiDAR data for...

Integrating Larval Dispersal, Permitting, and Logistical Factors Within a Validated Habitat Suitability Index for Oyster Restoration

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Brandon J. Puckett

2018-04-01

Full Text Available Habitat suitability index (HSI models are increasingly used to guide ecological restoration. Successful restoration is a byproduct of several factors, including physical and biological processes, as well as permitting and logistical considerations. Rarely are factors from all of these categories included in HSI models, despite their combined relevance to common restoration goals such as population persistence. We developed a Geographic Information System (GIS-based HSI for restoring persistent high-relief subtidal oyster (Crassostrea virginica reefs protected from harvest (i.e., sanctuaries in Pamlico Sound, North Carolina, USA. Expert stakeholder input identified 17 factors to include in the HSI. Factors primarily represented physical (e.g., salinity and biological (e.g., larval dispersal processes relevant to oyster restoration, but also included several relevant permitting (e.g., presence of seagrasses and logistical (e.g., distance to restoration material stockpile sites considerations. We validated the model with multiple years of oyster density data from existing sanctuaries, and compared HSI output with distributions of oyster reefs from the late 1800's. Of the 17 factors included in the model, stakeholders identified four factors—salinity, larval export from existing oyster sanctuaries, larval import to existing sanctuaries, and dissolved oxygen—most critical to oyster sanctuary site selection. The HSI model provided a quantitative scale over which a vast water body (~6,000 km2 was narrowed down by 95% to a much smaller suite of optimal (top 1% HSI and suitable (top 5% HSI locations for oyster restoration. Optimal and suitable restoration locations were clustered in northeast and southwest Pamlico Sound. Oyster density in existing sanctuaries, normalized for time since reef restoration, was a positive exponential function of HSI, providing validation for the model. Only a small portion (10–20% of historical reef locations

Computational fluid dynamics-habitat suitability index (CFD-HSI) modelling as an exploratory tool for assessing passability of riverine migratory challenge zones for fish

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Haro, Alexander J.; Chelminski, Michael; Dudley, Robert W.

2015-01-01

We developed two-dimensional computational fluid hydraulics-habitat suitability index (CFD-HSI) models to identify and qualitatively assess potential zones of shallow water depth and high water velocity that may present passage challenges for five major anadromous fish species in a 2.63-km reach of the main stem Penobscot River, Maine, as a result of a dam removal downstream of the reach. Suitability parameters were based on distribution of fish lengths and body depths and transformed to cruising, maximum sustained and sprint swimming speeds. Zones of potential depth and velocity challenges were calculated based on the hydraulic models; ability of fish to pass a challenge zone was based on the percent of river channel that the contiguous zone spanned and its maximum along-current length. Three river flows (low: 99.1 m3 sec-1; normal: 344.9 m3 sec-1; and high: 792.9 m3 sec-1) were modelled to simulate existing hydraulic conditions and hydraulic conditions simulating removal of a dam at the downstream boundary of the reach. Potential depth challenge zones were nonexistent for all low-flow simulations of existing conditions for deeper-bodied fishes. Increasing flows for existing conditions and removal of the dam under all flow conditions increased the number and size of potential velocity challenge zones, with the effects of zones being more pronounced for smaller species. The two-dimensional CFD-HSI model has utility in demonstrating gross effects of flow and hydraulic alteration, but may not be as precise a predictive tool as a three-dimensional model. Passability of the potential challenge zones cannot be precisely quantified for two-dimensional or three-dimensional models due to untested assumptions and incomplete data on fish swimming performance and behaviours.

Assessment of Climate Suitability of Maize in South Korea

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Hyun, S.; Choi, D.; Seo, B.

2017-12-01

Assessing suitable areas for crops would be useful to design alternate cropping systems as an adaptation option to climate change adaptation. Although suitable areas could be identified by using a crop growth model, it would require a number of input parameters including cultivar and soil. Instead, a simple climate suitability model, e.g., EcoCrop model, could be used for an assessment of climate suitability for a major grain crop. The objective of this study was to assess of climate suitability for maize using the EcoCrop model under climate change conditions in Korea. A long term climate data from 2000 - 2100 were compiled from weather data source. The EcoCrop model implemented in R was used to determine climate suitability index at each grid cell. Overall, the EcoCrop model tended to identify suitable areas for maize production near the coastal areas whereas the actual major production areas located in inland areas. It is likely that the discrepancy between assessed and actual crop production areas would result from the socioeconomic aspects of maize production. Because the price of maize is considerably low, maize has been grown in an area where moisture and temperature conditions would be less than optimum. In part, a simple algorithm to predict climate suitability for maize would caused a relatively large error in climate suitability assessment under the present climate conditions. In 2050s, the climate suitability for maize increased in a large areas in southern and western part of Korea. In particular, the plain areas near the coastal region had considerably greater suitability index in the future compared with mountainous areas. The expansion of suitable areas for maize would help crop production policy making such as the allocation of rice production area for other crops due to considerably less demand for the rice in Korea.

Assessing habitat selection when availability changes

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Arthur, S.; Garner, G.; ,

1996-01-01

We present a method of comparing data on habitat use and availability that allows availability to differ among observations. This method is applicable when habitats change over time and when animals are unable to move throughout a predetermined study area between observations. We used maximum-likelihood techniques to derive an index that estimates the probability that each habitat type would be used if all were equally available. We also demonstrate how these indices can be used to compare relative use of available habitats, assign them ranks, and assess statistical differences between pairs of indices. The set of these indices for all habitats can be compared between groups of animals that represent different seasons, sex or age classes, or experimental treatments. This method allows quantitative comparisons among types and is not affected by arbitrary decisions about which habitats to include in the study. We provide an example by comparing the availability of four categories of sea ice concentration to their use by adult female polar bears, whose movements were monitored by satellite radio tracking in the Bering and Chukchi Seas during 1990. Use of ice categories by bears was nonrandom, and the pattern of use differed between spring and late summer seasons.

Understanding Existing Salmonid Habitat Availability and Connectivity to Improve River Management

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Duffin, J.; Yager, E.; Tonina, D.; Benjankar, R. M.

2017-12-01

In the Pacific Northwest river restoration is common for salmon conservation. Mangers need methods to help target restoration to problem areas in rivers to create habitat that meets a species' needs. Hydraulic models and habitat suitability curves provide basic information on habitat availability and overall quality, but these analyses need to be expanded to address habitat quality based on the accessibility of habitats required for multiple life stages. Scientists are starting to use connectivity measurements to understand the longitudinal proximity of habitat patches, which can be used to address the habitat variability of a reach. By evaluating the availability and quality of habitat and calculating the connectivity between complementary habitats, such as spawning and rearing habitats, we aim to identify areas that should be targeted for restoration. To meet these goals, we assessed Chinook salmon habitat on the Lemhi River in Idaho. The depth and velocity outputs from a 2D hydraulic model are used in conjunction with locally created habitat suitability curves to evaluate the availability and quality of habitat for multiple Chinook salmon life stages. To assess the variability of the habitat, connectivity between habitat patches necessary for different life stages is calculated with a proximity index. A spatial representation of existing habitat quality and connectivity between complimentary habitats can be linked to river morphology by the evaluation of local geomorphic characteristics, including sinuosity and channel units. The understanding of the current habitat availability for multiple life stage needs, the connectivity between these habitat patches, and their relationship with channel morphology can help managers better identify restoration needs and direct their limited resources.

Distribution and habitat suitability index model for the Andean catfish Astroblepus ubidiai (Pisces: Siluriformes in Ecuador

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Luis A Vélez-Espino

2006-06-01

Full Text Available In conservation biology there is a basic need to determine habitat suitability and availability. Astroblepus ubidiai (Siluriforms, the only native fish in the highlands of Imbabura province in the Ecuadorian Andes, was abundant in the past in the Imbakucha watershed and adjacent drainages, but currently it is restricted to a few isolated refuges. Conservation actions are needed if this unique fish is to persist. A Habitat Suitability Index (HSI for the species has been developed in order to aid management decisions. In this HIS model biomass density (B was selected as a better indicator of habitat quality than either abundance or density. A population well-being index (PI was constructed with the combination of B and an indicator of fish health (proportion of fish in the population with parasites and deformities. Based in other models of benthic fish the habitat variables current velocity, flow, depth, width, cover, invertebrate composition, vegetation type, terrestrial vegetation, land use, substrate, temperature, pH, TDS, oxygen, altitude, and slope were included in the analysis. An anthropogenic perturbation index (H and a fragment isolation index (FII were developed and included as habitat variables as well. The HSI model was applied to refuges and a sample of 15 aquatic bodies without fish populations within the study region. From the sampled sites without A. ubidiai 26.6% presented low quality, and the remaining 73.3% had medium quality according to the HSI estimated. Good quality habitat for dispersal, escape or translocations is rare in the region. The low HSIs estimated in some of the refuges suggests that current populations are not settled in the most favorable habitat but in the habitat least favorable to the agents of decline. Rev. Biol. Trop. 54(2: 623-638. Epub 2006 Jun 01.Astroblepus ubidiai (Siluriformes, el único pez nativo de las alturas de Imbabura, en los Andes Ecuatorianos, era un recurso abundante en el pasado

Using environmental niche modeling to find suitable habitats for the Hard-ground Barasingha in Madhya Pradesh, India

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C. P. Singh

2015-09-01

Full Text Available The subspecies of Swamp Deer, the Hard-ground Barasingha (Rucervus duvaucelii branderi Pocock, is presently found only in Kanha Tiger Reserve (KTR in Madhya Pradesh, India. This subspecies is highly vulnerable to extinction, and reintroduction in suitable sites is the need of the hour.  Environmental niche models (GARP, SVM, ED, CSM aimed at providing a detailed prediction of species distribution by relating presence of species to 19 bioclimatic indices were developed, using swamp deer occurrence records in KTR. The predictions were appropriately weighted with the prevailing LU/LC classes to identify suitable habitats in Madhya Pradesh, India. The result shows that the southern region of Madhya Pradesh is suitable for the sustenance of Barasingha with varying degrees of habitability. Vicarious validation shows that most of these forest areas were the same as that of historical records dating back to 50 years. However, land use maps can help identify areas where this subspecies can be reintroduced. 

Impacts of temperature on giant panda habitat in the north Minshan Mountains.

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Liu, Gang; Guan, Tianpei; Dai, Qiang; Li, Huixin; Gong, Minghao

2016-02-01

Understanding the impacts of meteorological factors on giant pandas is necessary for future conservation measures in response to global climate change. We integrated temperature data with three main habitat parameters (elevation, vegetation type, and bamboo species) to evaluate the influence of climate change on giant panda habitat in the northern Minshan Mountains using a habitat assessment model. Our study shows that temperature (relative importance = 25.1%) was the second most important variable influencing giant panda habitat excepting the elevation. There was a significant negative correlation between temperature and panda presence (ρ = -0.133, P pandas within the study area was 18-21°C, followed by 15-17°C and 22-24°C. The overall suitability of giant panda habitats will increase by 2.7%, however, it showed a opposite variation patterns between the eastern and northwestern region of the study area. Suitable and subsuitable habitats in the northwestern region of the study area, which is characterized by higher elevation and latitude, will increase by 18007.8 hm(2) (9.8% habitat suitability), while the eastern region will suffer a decrease of 9543.5 hm(2) (7.1% habitat suitability). Our results suggest that increasing areas of suitable giant panda habitat will support future giant panda expansion, and food shortage and insufficient living space will not arise as problems in the northwest Minshan Mountains, which means that giant pandas can adapt to climate change, and therefore may be resilient to climate change. Thus, for the safety and survival of giant pandas in the Baishuijiang Reserve, we propose strengthening the giant panda monitoring program in the west and improving the integrity of habitats to promote population dispersal with adjacent populations in the east.

A management-oriented framework for selecting metrics used to assess habitat- and path-specific quality in spatially structured populations

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Nicol, Sam; Wiederholt, Ruscena; Diffendorfer, James E.; Mattsson, Brady; Thogmartin, Wayne E.; Semmens, Darius J.; Laura Lopez-Hoffman,; Norris, Ryan

2016-01-01

Mobile species with complex spatial dynamics can be difficult to manage because their population distributions vary across space and time, and because the consequences of managing particular habitats are uncertain when evaluated at the level of the entire population. Metrics to assess the importance of habitats and pathways connecting habitats in a network are necessary to guide a variety of management decisions. Given the many metrics developed for spatially structured models, it can be challenging to select the most appropriate one for a particular decision. To guide the management of spatially structured populations, we define three classes of metrics describing habitat and pathway quality based on their data requirements (graph-based, occupancy-based, and demographic-based metrics) and synopsize the ecological literature relating to these classes. Applying the first steps of a formal decision-making approach (problem framing, objectives, and management actions), we assess the utility of metrics for particular types of management decisions. Our framework can help managers with problem framing, choosing metrics of habitat and pathway quality, and to elucidate the data needs for a particular metric. Our goal is to help managers to narrow the range of suitable metrics for a management project, and aid in decision-making to make the best use of limited resources.

The global distribution of deep-water Antipatharia habitat

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Yesson, Chris; Bedford, Faye; Rogers, Alex D.; Taylor, Michelle L.

2017-11-01

Antipatharia are a diverse group of corals with many species found in deep water. Many Antipatharia are habitat for associates, have extreme longevity and some species can occur beyond 8500 m depth. As they are major constituents of'coral gardens', which are Vulnerable Marine Ecosystems (VMEs), knowledge of their distribution and environmental requirements is an important pre-requisite for informed conservation planning particularly where the expense and difficulty of deep-sea sampling prohibits comprehensive surveys. This study uses a global database of Antipatharia distribution data to perform habitat suitability modelling using the Maxent methodology to estimate the global extent of black coral habitat suitability. The model of habitat suitability is driven by temperature but there is notable influence from other variables of topography, surface productivity and oxygen levels. This model can be used to predict areas of suitable habitat, which can be useful for conservation planning. The global distribution of Antipatharia habitat suitability shows a marked contrast with the distribution of specimen observations, indicating that many potentially suitable areas have not been sampled, and that sampling effort has been disproportionate to shallow, accessible areas inside marine protected areas (MPAs). Although 25% of Antipatharia observations are located in MPAs, only 7-8% of predicted suitable habitat is protected, which is short of the Convention on Biological Diversity target to protect 10% of ocean habitats by 2020.

Applying a two-dimensional morphodynamic model to assess impacts to Chinook salmon spawning habitat from dam removal

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Lee, A. A.; Crosato, A.; Omer, A. Y. A.; Bregoli, F.

2017-12-01

The need for accurate and robust predictive methods of assessing fluvial ecosystems is highlighted by the accelerating practice of dam removal. Dam removal can be a restorative measure, but the sudden release of impounded sediment and change in flow regime may negatively impact aquatic biota and their habitat. This study assesses the performance of a quasi-three-dimensional morphodynamic numerical model, coupled with habitat suitability indices, to predict short-term impacts to Chinook salmon (Oncorhynchus tshawytscha) spawning habitat from dam removal. The 2007 removal of Marmot Dam on the Sandy River (Oregon, U.S.A.) is used as a case study. Delft3D-FLOW is employed to simulate changes in river channel topography, sediment composition and hydrodynamic conditions for a 20-kilometer reach of the Sandy River. The transport of non-uniform sediment and three-dimensional flow effects are included in the model. Output parameters such as flow depth, velocity and substrate are processed to evaluate habitat quality in the year following the Marmot Dam removal. Impacts are evaluated across four life-stages of Chinook salmon. As a hindcast analysis, the morphodynamic model sufficiently reproduces the evolution of river morphology at the reach-scale while requiring only a low level of calibration. The model performs well in predicting impacts to fish passage, but carries more uncertainty for developing life stages. By coupling flow-sediment-biota interactions, this method shows strong potential for habitat assessment in unsteady and non-uniform environments. Computation time is a primary constraint, as it limits grid-cell resolution, modelling of suspended sediment and capacity to characterize the sediment grain size distribution. Research on the effects of suspended sediment on habitat quality is ongoing, and further research is recommended for modelling reservoir erosion processes numerically.

Use of Occupancy Models to Evaluate Expert Knowledge-based Species-Habitat Relationships

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Monica N. Iglecia

2012-12-01

Full Text Available Expert knowledge-based species-habitat relationships are used extensively to guide conservation planning, particularly when data are scarce. Purported relationships describe the initial state of knowledge, but are rarely tested. We assessed support in the data for suitability rankings of vegetation types based on expert knowledge for three terrestrial avian species in the South Atlantic Coastal Plain of the United States. Experts used published studies, natural history, survey data, and field experience to rank vegetation types as optimal, suitable, and marginal. We used single-season occupancy models, coupled with land cover and Breeding Bird Survey data, to examine the hypothesis that patterns of occupancy conformed to species-habitat suitability rankings purported by experts. Purported habitat suitability was validated for two of three species. As predicted for the Eastern Wood-Pewee (Contopus virens and Brown-headed Nuthatch (Sitta pusilla, occupancy was strongly influenced by vegetation types classified as "optimal habitat" by the species suitability rankings for nuthatches and wood-pewees. Contrary to predictions, Red-headed Woodpecker (Melanerpes erythrocephalus models that included vegetation types as covariates received similar support by the data as models without vegetation types. For all three species, occupancy was also related to sampling latitude. Our results suggest that covariates representing other habitat requirements might be necessary to model occurrence of generalist species like the woodpecker. The modeling approach described herein provides a means to test expert knowledge-based species-habitat relationships, and hence, help guide conservation planning.

Habitat Heterogeneity Variably Influences Habitat Selection by Wild Herbivores in a Semi-Arid Tropical Savanna Ecosystem.

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Victor K Muposhi

Full Text Available An understanding of the habitat selection patterns by wild herbivores is critical for adaptive management, particularly towards ecosystem management and wildlife conservation in semi arid savanna ecosystems. We tested the following predictions: (i surface water availability, habitat quality and human presence have a strong influence on the spatial distribution of wild herbivores in the dry season, (ii habitat suitability for large herbivores would be higher compared to medium-sized herbivores in the dry season, and (iii spatial extent of suitable habitats for wild herbivores will be different between years, i.e., 2006 and 2010, in Matetsi Safari Area, Zimbabwe. MaxEnt modeling was done to determine the habitat suitability of large herbivores and medium-sized herbivores. MaxEnt modeling of habitat suitability for large herbivores using the environmental variables was successful for the selected species in 2006 and 2010, except for elephant (Loxodonta africana for the year 2010. Overall, large herbivores probability of occurrence was mostly influenced by distance from rivers. Distance from roads influenced much of the variability in the probability of occurrence of medium-sized herbivores. The overall predicted area for large and medium-sized herbivores was not different. Large herbivores may not necessarily utilize larger habitat patches over medium-sized herbivores due to the habitat homogenizing effect of water provisioning. Effect of surface water availability, proximity to riverine ecosystems and roads on habitat suitability of large and medium-sized herbivores in the dry season was highly variable thus could change from one year to another. We recommend adaptive management initiatives aimed at ensuring dynamic water supply in protected areas through temporal closure and or opening of water points to promote heterogeneity of wildlife habitats.

Concurrent assessment of fish and habitat in warmwater streams in Wyoming

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Quist, M.C.; Hubert, W.A.; Rahel, F.J.

2006-01-01

Fisheries research and management in North America have focused largely on sport fishes, but native non-game fishes have attracted increased attention due to their declines. The Warmwater Stream Assessment (WSA) was developed to evaluate simultaneously both fish and habitat in Wyoming streams by a process that includes three major components: (1) stream-reach selection and accumulation of existing information, (2) fish and habitat sampling and (3) summarisation and evaluation of fish and habitat information. Fish are sampled by electric fishing or seining and habitat is measured at reach and channel-unit (i.e. pool, run, riffle, side channel, or backwater) scales. Fish and habitat data are subsequently summarised using a data-matrix approach. Hierarchical decision trees are used to assess critical habitat requirements for each fish species expected or found in the reach. Combined measurements of available habitat and the ecology of individual species contribute to the evaluation of the observed fish assemblage. The WSA incorporates knowledge of the fish assemblage and habitat features to enable inferences of factors likely influencing both the fish assemblage and their habitat. The WSA was developed for warmwater streams in Wyoming, but its philosophy, process and conceptual basis may be applied to environmental assessments in other geographical areas. ?? 2006 Blackwell Publishing Ltd.

Modelling the spatial and seasonal distribution of suitable habitats of schistosomiasis intermediate host snails using Maxent in Ndumo area, KwaZulu-Natal Province, South Africa

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Tawanda Manyangadze

2016-11-01

Full Text Available Abstract Background Schistosomiasis is a snail-borne disease endemic in sub-Saharan Africa transmitted by freshwater snails. The distribution of schistosomiasis coincides with that of the intermediate hosts as determined by climatic and environmental factors. The aim of this paper was to model the spatial and seasonal distribution of suitable habitats for Bulinus globosus and Biomphalaria pfeifferi snail species (intermediate hosts for Schistosoma haematobium and Schistosoma mansoni, respectively in the Ndumo area of uMkhanyakude district, South Africa. Methods Maximum Entropy (Maxent modelling technique was used to predict the distribution of suitable habitats for B. globosus and B. pfeifferi using presence-only datasets with ≥ 5 and ≤ 12 sampling points in different seasons. Precipitation, maximum and minimum temperatures, Normalised Difference Vegetation Index (NDVI, Normalised Difference Water Index (NDWI, pH, slope and Enhanced Vegetation Index (EVI were the background variables in the Maxent models. The models were validated using the area under the curve (AUC and omission rate. Results The predicted suitable habitats for intermediate snail hosts varied with seasons. The AUC for models in all seasons ranged from 0.71 to 1 and the prediction rates were between 0.8 and 0.9. Although B. globosus was found at more localities in the Ndumo area, there was also evidence of cohabiting with B. pfiefferi at some of the locations. NDWI had significant contribution to the models in all seasons. Conclusion The Maxent model is robust in snail habitat suitability modelling even with small dataset of presence-only sampling sites. Application of the methods and design used in this study may be useful in developing a control and management programme for schistosomiasis in the Ndumo area.

Environmental flow assessments for transformed estuaries

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Sun, Tao; Zhang, Heyue; Yang, Zhifeng; Yang, Wei

2015-01-01

Here, we propose an approach to environmental flow assessment that considers spatial pattern variations in potential habitats affected by river discharges and tidal currents in estuaries. The approach comprises four steps: identifying and simulating the distributions of critical environmental factors for habitats of typical species in an estuary; mapping of suitable habitats based on spatial distributions of the Habitat Suitability Index (HSI) and adopting the habitat aggregation index to understand fragmentation of potential suitable habitats; defining variations in water requirements for a certain species using trade-off analysis for different protection objectives; and recommending environmental flows in the estuary considering the compatibility and conflict of freshwater requirements for different species. This approach was tested using a case study in the Yellow River Estuary. Recommended environmental flows were determined by incorporating the requirements of four types of species into the assessments. Greater variability in freshwater inflows could be incorporated into the recommended environmental flows considering the adaptation of potential suitable habitats with variations in the flow regime. Environmental flow allocations should be conducted in conjunction with land use conflict management in estuaries. Based on the results presented here, the proposed approach offers flexible assessment of environmental flow for aquatic ecosystems that may be subject to future change.

Evaluation of Limiting Climatic Factors and Simulation of a Climatically Suitable Habitat for Chinese Sea Buckthorn.

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Guoqing Li

Full Text Available Chinese sea buckthorn (Hippophae rhamnoides subsp. sinensis has considerable economic potential and plays an important role in reclamation and soil and water conservation. For scientific cultivation of this species across China, we identified the key climatic factors and explored climatically suitable habitat in order to maximize survival of Chinese sea buckthorn using MaxEnt and GIS tools, based on 98 occurrence records from herbarium and publications and 13 climatic factors from Bioclim, Holdridge life zone and Kria' index variables. Our simulation showed that the MaxEnt model performance was significantly better than random, with an average test AUC value of 0.93 with 10-fold cross validation. A jackknife test and the regularized gain change, which were applied to the training algorithm, showed that precipitation of the driest month (PDM, annual precipitation (AP, coldness index (CI and annual range of temperature (ART were the most influential climatic factors in limiting the distribution of Chinese sea buckthorn, which explained 70.1% of the variation. The predicted map showed that the core of climatically suitable habitat was distributed from the southwest to northwest of Gansu, Ningxia, Shaanxi and Shanxi provinces, where the most influential climate variables were PDM of 1.0-7.0 mm, AP of 344.0-1089.0 mm, CI of -47.7-0.0°C, and ART of 26.1-45.0°C. We conclude that the distribution patterns of Chinese sea buckthorn are related to the northwest winter monsoon, the southwest summer monsoon and the southeast summer monsoon systems in China.

Transplantation assessment of degraded Posidonia oceanica habitats: site selection and long-term monitoring

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M. PIRROTTA

2014-09-01

Full Text Available A model developed for Zostera marina was adapted and used to select suitable areas for Posidonia oceanica transplantation in the Gulf of Palermo, where recent rehabilitation programmes have reduced human pressure. This model consists of three steps: (1 habitat selection, by calculation of the Preliminary Transplant Suitability Index (PTSI; (2 field assessments and test-transplanting, to evaluate the site suitability and to estimate the effects of tearing on transplant units (about 50%; (3 identification of suitable restoration sites, by calculation of the Transplant Suitability Index (TSI. A new parameter was added to the literature model: the number of grids detached, which is linked to factors (hydrodynamic regime, anchoring, fishing that have a potentially great effect on the final outcome of the transplant. Only one site (TSI = 16 in the Gulf of Palermo was indicated as potentially suitable for restoration with P. oceanica. In this site, a transplant of 40 m2 was implemented. From 2008 to 2014, transplant effectiveness was evaluated in terms of establishment, detachment and mortality of cuttings and shoot density. The long-term monitoring (6 years allowed us to detect changes in the structural conditions of the transplanted meadow and to identify the possible turning point in P. oceanica recovery (2 years after transplanting. Moreover, 6 years after transplantation the P. oceanica meadow has exceeded the transplant shoot density of about 16%, with a mean and a maximum value of 11.6 and 17 shoots per cutting, respectively.

Habitat features and predictive habitat modeling for the Colorado chipmunk in southern New Mexico

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Rivieccio, M.; Thompson, B.C.; Gould, W.R.; Boykin, K.G.

2003-01-01

Two subspecies of Colorado chipmunk (state threatened and federal species of concern) occur in southern New Mexico: Tamias quadrivittatus australis in the Organ Mountains and T. q. oscuraensis in the Oscura Mountains. We developed a GIS model of potentially suitable habitat based on vegetation and elevation features, evaluated site classifications of the GIS model, and determined vegetation and terrain features associated with chipmunk occurrence. We compared GIS model classifications with actual vegetation and elevation features measured at 37 sites. At 60 sites we measured 18 habitat variables regarding slope, aspect, tree species, shrub species, and ground cover. We used logistic regression to analyze habitat variables associated with chipmunk presence/absence. All (100%) 37 sample sites (28 predicted suitable, 9 predicted unsuitable) were classified correctly by the GIS model regarding elevation and vegetation. For 28 sites predicted suitable by the GIS model, 18 sites (64%) appeared visually suitable based on habitat variables selected from logistic regression analyses, of which 10 sites (36%) were specifically predicted as suitable habitat via logistic regression. We detected chipmunks at 70% of sites deemed suitable via the logistic regression models. Shrub cover, tree density, plant proximity, presence of logs, and presence of rock outcrop were retained in the logistic model for the Oscura Mountains; litter, shrub cover, and grass cover were retained in the logistic model for the Organ Mountains. Evaluation of predictive models illustrates the need for multi-stage analyses to best judge performance. Microhabitat analyses indicate prospective needs for different management strategies between the subspecies. Sensitivities of each population of the Colorado chipmunk to natural and prescribed fire suggest that partial burnings of areas inhabited by Colorado chipmunks in southern New Mexico may be beneficial. These partial burnings may later help avoid a fire

River habitat assessment for ecological restoration of Wei River Basin, China.

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Yang, Tao; Wang, Shuo; Li, Xiaoping; Wu, Ting; Li, Li; Chen, Jia

2018-04-11

As an important composition component of river ecosystems, river habitats must undergo quality assessment to potentially provide scientific basis for river ecological restoration. Substrate composition, habitat complexity, bank erosion degree, river meandering degree, human activity intensity, vegetation buffer width, water quality, and water condition were determined as indicators for river habitat assessment. The comprehensive habitat quality index (CHQI) was established for the Wei River Basin. In addition, the indicator values were determined on the basis of a field investigation at 12 national hydrological stations distributed across the Wei, Jing, and Beiluo Rivers. The analytic hierarchy process was used to determine the indicator weights and thus distinguish the relative importance of the assessment indicator system. Results indicated that the average CHQIs for the Wei, Jing, and Beiluo Rivers were 0.417, 0.508, and 0.304, respectively. The river habitat quality for the three rivers was well. As for the whole river basin, the river habitat quality for 25% of the cross section was very well, the other 25% was well, and the 50% remaining was in critical state. The river habitat quality of the Jing River was better than that of the Wei and Beiluo Rivers.

Revised Methods for Characterizing Stream Habitat in the National Water-Quality Assessment Program

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Fitzpatrick, Faith A.; Waite, Ian R.; D'Arconte, Patricia J.; Meador, Michael R.; Maupin, Molly A.; Gurtz, Martin E.

1998-01-01

Stream habitat is characterized in the U.S. Geological Survey's National Water-Quality Assessment (NAWQA) Program as part of an integrated physical, chemical, and biological assessment of the Nation's water quality. The goal of stream habitat characterization is to relate habitat to other physical, chemical, and biological factors that describe water-quality conditions. To accomplish this goal, environmental settings are described at sites selected for water-quality assessment. In addition, spatial and temporal patterns in habitat are examined at local, regional, and national scales. This habitat protocol contains updated methods for evaluating habitat in NAWQA Study Units. Revisions are based on lessons learned after 6 years of applying the original NAWQA habitat protocol to NAWQA Study Unit ecological surveys. Similar to the original protocol, these revised methods for evaluating stream habitat are based on a spatially hierarchical framework that incorporates habitat data at basin, segment, reach, and microhabitat scales. This framework provides a basis for national consistency in collection techniques while allowing flexibility in habitat assessment within individual Study Units. Procedures are described for collecting habitat data at basin and segment scales; these procedures include use of geographic information system data bases, topographic maps, and aerial photographs. Data collected at the reach scale include channel, bank, and riparian characteristics.

Assessment and management of dead-wood habitat

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Hagar, Joan

2007-01-01

The Bureau of Land Management (BLM) is in the process of revising its resource management plans for six districts in western and southern Oregon as the result of the settlement of a lawsuit brought by the American Forest Resource Council. A range of management alternatives is being considered and evaluated including at least one that will minimize reserves on O&C lands. In order to develop the bases for evaluating management alternatives, the agency needs to derive a reasonable range of objectives for key issues and resources. Dead-wood habitat for wildlife has been identified as a key resource for which decision-making tools and techniques need to be refined and clarified. Under the Northwest Forest Plan, reserves were to play an important role in providing habitat for species associated with dead wood (U.S. Department of Agriculture Forest Service and U.S. Department of the Interior Bureau of Land Management, 1994). Thus, the BLM needs to: 1) address the question of how dead wood will be provided if reserves are not included as a management strategy in the revised Resource Management Plan, and 2) be able to evaluate the effects of alternative land management approaches. Dead wood has become an increasingly important conservation issue in managed forests, as awareness of its function in providing wildlife habitat and in basic ecological processes has dramatically increased over the last several decades (Laudenslayer et al., 2002). A major concern of forest managers is providing dead wood habitat for terrestrial wildlife. Wildlife in Pacific Northwest forests have evolved with disturbances that create large amounts of dead wood; so, it is not surprising that many species are closely associated with standing (snags) or down, dead wood. In general, the occurrence or abundance of one-quarter to one-third of forest-dwelling vertebrate wildlife species, is strongly associated with availability of suitable dead-wood habitat (Bunnell et al., 1999; Rose et al., 2001). In

Assessing landscape constraints on species abundance: Does the neighborhood limit species response to local habitat conservation programs?

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Jorgensen, Christopher F.; Powell, Larkin A.; Lusk, Jeffrey J.; Bishop, Andrew A.; Fontaine, Joseph J.

2014-01-01

Landscapes in agricultural systems continue to undergo significant change, and the loss of biodiversity is an ever-increasing threat. Although habitat restoration is beneficial, management actions do not always result in the desired outcome. Managers must understand why management actions fail; yet, past studies have focused on assessing habitat attributes at a single spatial scale, and often fail to consider the importance of ecological mechanisms that act across spatial scales. We located survey sites across southern Nebraska, USA and conducted point counts to estimate Ring-necked Pheasant abundance, an economically important species to the region, while simultaneously quantifying landscape effects using a geographic information system. To identify suitable areas for allocating limited management resources, we assessed land cover relationships to our counts using a Bayesian binomial-Poisson hierarchical model to construct predictive Species Distribution Models of relative abundance. Our results indicated that landscape scale land cover variables severely constrained or, alternatively, facilitated the positive effects of local land management for Ring-necked Pheasants.

Predictive habitat modelling as a tool to assess the change in distribution and extent of an OSPAR priority habitat under an increased ocean temperature scenario: consequences for marine protected area networks and management.

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Gormley, Kate S G; Porter, Joanne S; Bell, Michael C; Hull, Angela D; Sanderson, William G

2013-01-01

The aims of this study were to determine the extent and distribution of an OSPAR priority habitat under current baseline ocean temperatures; to illustrate the prospect for habitat loss under a changing ocean temperature scenario; and to demonstrate the potential application of predictive habitat mapping in "future-proofing" conservation and biodiversity management. Maxent modelling and GIS environmental envelope analysis of the biogenic bed forming species, Modiolus modiolus was carried out. The Maxent model was tested and validated using 75%/25% training/test occurrence records and validated against two sampling biases (the whole study area and a 20km buffer). The model was compared to the envelope analysis and the area under the receiver operating characteristic curve (Area Under the curve; AUC) was evaluated. The performance of the Maxent model was rated as 'good' to 'excellent' on all replicated runs and low variation in the runs was recorded from the AUC values. The extent of "most suitable", "less suitable" and "unsuitable" habitat was calculated for the baseline year (2009) and the projected increased ocean temperature scenarios (2030, 2050, 2080 and 2100). A loss of 100% of "most suitable" habitat was reported by 2080. Maintaining a suitable level of protection of marine habitats/species of conservation importance may require management of the decline and migration rather than maintenance of present extent. Methods applied in this study provide the initial application of a plausible "conservation management tool".

Predictive habitat modelling as a tool to assess the change in distribution and extent of an OSPAR priority habitat under an increased ocean temperature scenario: consequences for marine protected area networks and management.

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Kate S G Gormley

Full Text Available The aims of this study were to determine the extent and distribution of an OSPAR priority habitat under current baseline ocean temperatures; to illustrate the prospect for habitat loss under a changing ocean temperature scenario; and to demonstrate the potential application of predictive habitat mapping in "future-proofing" conservation and biodiversity management. Maxent modelling and GIS environmental envelope analysis of the biogenic bed forming species, Modiolus modiolus was carried out. The Maxent model was tested and validated using 75%/25% training/test occurrence records and validated against two sampling biases (the whole study area and a 20km buffer. The model was compared to the envelope analysis and the area under the receiver operating characteristic curve (Area Under the curve; AUC was evaluated. The performance of the Maxent model was rated as 'good' to 'excellent' on all replicated runs and low variation in the runs was recorded from the AUC values. The extent of "most suitable", "less suitable" and "unsuitable" habitat was calculated for the baseline year (2009 and the projected increased ocean temperature scenarios (2030, 2050, 2080 and 2100. A loss of 100% of "most suitable" habitat was reported by 2080. Maintaining a suitable level of protection of marine habitats/species of conservation importance may require management of the decline and migration rather than maintenance of present extent. Methods applied in this study provide the initial application of a plausible "conservation management tool".

Assessment of Brown Bear\\'s (Ursus arctos syriacus Winter Habitat Using Geographically Weighted Regression and Generalized Linear Model in South of Iran

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A. A. Zarei

2016-03-01

Full Text Available Winter dens are one of the important components of brown bear's (Ursus arctos syriacus habitat, affecting their reproduction and survival. Therefore identification of factors affecting the habitat selection and suitable denning areas in the conservation of our largest carnivore is necessary. We used Geographically Weighted Logistic Regression (GWLR and Generalized Linear Model (GLM for modeling suitability of denning habitat in Kouhkhom region in Fars province. In the present research, 20 dens (presence locations and 20 caves where signs of bear were not found (absence locations were used as dependent variables and six environmental factors were used for each location as independent variables. The results of GLM showed that variables of distance to settlements, altitude, and distance to water were the most important parameters affecting suitability of the brown bear's denning habitat. The results of GWLR showed the significant local variations in the relationship between occurrence of brown bear dens and the variable of distance to settlements. Based on the results of both models, suitable habitats for denning of the species are impassable areas in the mountains and inaccessible for humans.

Modeling Habitat Suitability of Migratory Birds from Remote Sensing Images Using Convolutional Neural Networks

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Su, Jin-He; Piao, Ying-Chao; Luo, Ze; Yan, Bao-Ping

2018-01-01

Simple Summary The understanding of the spatio-temporal distribution of the species habitats would facilitate wildlife resource management and conservation efforts. Existing methods have poor performance due to the limited availability of training samples. More recently, location-aware sensors have been widely used to track animal movements. The aim of the study was to generate suitability maps of bar-head geese using movement data coupled with environmental parameters, such as remote sensing images and temperature data. Therefore, we modified a deep convolutional neural network for the multi-scale inputs. The results indicate that the proposed method can identify the areas with the dense goose species around Qinghai Lake. In addition, this approach might also be interesting for implementation in other species with different niche factors or in areas where biological survey data are scarce. Abstract With the application of various data acquisition devices, a large number of animal movement data can be used to label presence data in remote sensing images and predict species distribution. In this paper, a two-stage classification approach for combining movement data and moderate-resolution remote sensing images was proposed. First, we introduced a new density-based clustering method to identify stopovers from migratory birds’ movement data and generated classification samples based on the clustering result. We split the remote sensing images into 16 × 16 patches and labeled them as positive samples if they have overlap with stopovers. Second, a multi-convolution neural network model is proposed for extracting the features from temperature data and remote sensing images, respectively. Then a Support Vector Machines (SVM) model was used to combine the features together and predict classification results eventually. The experimental analysis was carried out on public Landsat 5 TM images and a GPS dataset was collected on 29 birds over three years. The results

GIS habitat analysis for lesser prairie-chickens in southeastern New Mexico

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Neville Paul

2006-12-01

Full Text Available Abstract Background We conducted Geographic Information System (GIS habitat analyses for lesser prairie-chicken (LPCH, Tympanuchus pallidicinctus conservation planning. The 876,799 ha study area included most of the occupied habitat for the LPCH in New Mexico. The objectives were to identify and quantify: 1. suitable LPCH habitat in New Mexico, 2. conversion of native habitats, 3. potential for habitat restoration, and 4. unsuitable habitat available for oil and gas activities. Results We found 16% of suitable habitat (6% of the study area distributed in 13 patches of at least 3,200 ha and 11% of suitable habitat (4% of the study area distributed in four patches over 7,238 ha. The area converted from native vegetation types comprised 17% of the study area. Ninety-five percent of agricultural conversion occurred on private lands in the northeastern corner of the study area. Most known herbicide-related conversions (82% occurred in rangelands in the western part of the study area, on lands managed primarily by the US Bureau of Land Management (BLM. We identified 88,190 ha (10% of the study area of habitats with reasonable restoration potential. Sixty-two percent of the primary population area (PPA contained occupied, suitable, or potentially suitable habitat, leaving 38% that could be considered for oil and gas development. Conclusion Although suitable LPCH habitat appears at first glance to be abundant in southeastern New Mexico, only a fraction of apparently suitable vegetation types constitute quality habitat. However, we identified habitat patches that could be restored through mesquite control or shin-oak reintroduction. The analysis also identified areas of unsuitable habitat with low restoration potential that could be targeted for oil and gas exploration, in lieu of occupied, high-quality habitats. Used in combination with GIS analysis and current LPCH population data, the habitat map represents a powerful conservation and management tool.

GIS habitat analysis for lesser prairie-chickens in southeastern New Mexico.

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Johnson, Kristine; Neville, Teri B; Neville, Paul

2006-12-04

We conducted Geographic Information System (GIS) habitat analyses for lesser prairie-chicken (LPCH, Tympanuchus pallidicinctus) conservation planning. The 876,799 ha study area included most of the occupied habitat for the LPCH in New Mexico. The objectives were to identify and quantify: 1. suitable LPCH habitat in New Mexico, 2. conversion of native habitats, 3. potential for habitat restoration, and 4. unsuitable habitat available for oil and gas activities. We found 16% of suitable habitat (6% of the study area) distributed in 13 patches of at least 3,200 ha and 11% of suitable habitat (4% of the study area) distributed in four patches over 7,238 ha. The area converted from native vegetation types comprised 17% of the study area. Ninety-five percent of agricultural conversion occurred on private lands in the northeastern corner of the study area. Most known herbicide-related conversions (82%) occurred in rangelands in the western part of the study area, on lands managed primarily by the US Bureau of Land Management (BLM). We identified 88,190 ha (10% of the study area) of habitats with reasonable restoration potential. Sixty-two percent of the primary population area (PPA) contained occupied, suitable, or potentially suitable habitat, leaving 38% that could be considered for oil and gas development. Although suitable LPCH habitat appears at first glance to be abundant in southeastern New Mexico, only a fraction of apparently suitable vegetation types constitute quality habitat. However, we identified habitat patches that could be restored through mesquite control or shin-oak reintroduction. The analysis also identified areas of unsuitable habitat with low restoration potential that could be targeted for oil and gas exploration, in lieu of occupied, high-quality habitats. Used in combination with GIS analysis and current LPCH population data, the habitat map represents a powerful conservation and management tool.

Linking hydrologic, physical and chemical habitat environments for the potential assessment of fish community rehabilitation in a developing city

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Zhao, C. S.; Yang, S. T.; Liu, C. M.; Dou, T. W.; Yang, Z. L.; Yang, Z. Y.; Liu, X. L.; Xiang, H.; Nie, S. Y.; Zhang, J. L.; Mitrovic, S. M.; Yu, Q.; Lim, R. P.

2015-04-01

Aquatic ecological rehabilitation is increasingly attracting considerable public and research attention. An effective method that requires less data and expertise would help in the assessment of rehabilitation potential and in the monitoring of rehabilitation activities as complicated theories and excessive data requirements on assemblage information make many current assessment models expensive and limit their wide use. This paper presents an assessment model for restoration potential which successfully links hydrologic, physical and chemical habitat factors to fish assemblage attributes drawn from monitoring datasets on hydrology, water quality and fish assemblages at a total of 144 sites, where 5084 fish were sampled and tested. In this model three newly developed sub-models, integrated habitat index (IHSI), integrated ecological niche breadth (INB) and integrated ecological niche overlap (INO), are established to study spatial heterogeneity of the restoration potential of fish assemblages based on gradient methods of habitat suitability index and ecological niche models. To reduce uncertainties in the model, as many fish species as possible, including important native fish, were selected as dominant species with monitoring occurring over several seasons to comprehensively select key habitat factors. Furthermore, a detrended correspondence analysis (DCA) was employed prior to a canonical correspondence analysis (CCA) of the data to avoid the "arc effect" in the selection of key habitat factors. Application of the model to data collected at Jinan City, China proved effective reveals that three lower potential regions that should be targeted in future aquatic ecosystem rehabilitation programs. They were well validated by the distribution of two habitat parameters: river width and transparency. River width positively influenced and transparency negatively influenced fish assemblages. The model can be applied for monitoring the effects of fish assemblage restoration

Structural habitat predicts functional dispersal habitat of a large carnivore: how leopards change spots.

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Fattebert, Julien; Robinson, Hugh S; Balme, Guy; Slotow, Rob; Hunter, Luke

2015-10-01

Natal dispersal promotes inter-population linkage, and is key to spatial distribution of populations. Degradation of suitable landscape structures beyond the specific threshold of an individual's ability to disperse can therefore lead to disruption of functional landscape connectivity and impact metapopulation function. Because it ignores behavioral responses of individuals, structural connectivity is easier to assess than functional connectivity and is often used as a surrogate for landscape connectivity modeling. However using structural resource selection models as surrogate for modeling functional connectivity through dispersal could be erroneous. We tested how well a second-order resource selection function (RSF) models (structural connectivity), based on GPS telemetry data from resident adult leopard (Panthera pardus L.), could predict subadult habitat use during dispersal (functional connectivity). We created eight non-exclusive subsets of the subadult data based on differing definitions of dispersal to assess the predictive ability of our adult-based RSF model extrapolated over a broader landscape. Dispersing leopards used habitats in accordance with adult selection patterns, regardless of the definition of dispersal considered. We demonstrate that, for a wide-ranging apex carnivore, functional connectivity through natal dispersal corresponds to structural connectivity as modeled by a second-order RSF. Mapping of the adult-based habitat classes provides direct visualization of the potential linkages between populations, without the need to model paths between a priori starting and destination points. The use of such landscape scale RSFs may provide insight into predicting suitable dispersal habitat peninsulas in human-dominated landscapes where mitigation of human-wildlife conflict should be focused. We recommend the use of second-order RSFs for landscape conservation planning and propose a similar approach to the conservation of other wide-ranging large

Habitat suitability mapping of Anopheles darlingi in the surroundings of the Manso hydropower plant reservoir, Mato Grosso, Central Brazil

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Miyazaki Rosina D

2007-03-01

Full Text Available Abstract Background Hydropower plants provide more than 78 % of Brazil's electricity generation, but the country's reservoirs are potential new habitats for main vectors of malaria. In a case study in the surroundings of the Manso hydropower plant in Mato Grosso state, Central Brazil, habitat suitability of Anopheles darlingi was studied. Habitat profile was characterized by collecting environmental data. Remote sensing and GIS techniques were applied to extract additional spatial layers of land use, distance maps, and relief characteristics for spatial model building. Results Logistic regression analysis and ROC curves indicate significant relationships between the environment and presence of An. darlingi. Probabilities of presence strongly vary as a function of land cover and distance from the lake shoreline. Vector presence was associated with spatial proximity to reservoir and semi-deciduous forests followed by Cerrado woodland. Vector absence was associated with open vegetation formations such as grasslands and agricultural areas. We suppose that non-significant differences of vector incidences between rainy and dry seasons are associated with the availability of anthropogenic breeding habitat of the reservoir throughout the year. Conclusion Satellite image classification and multitemporal shoreline simulations through DEM-based GIS-analyses consist in a valuable tool for spatial modeling of A. darlingi habitats in the studied hydropower reservoir area. Vector presence is significantly increased in forested areas near reservoirs in bays protected from wind and wave action. Construction of new reservoirs under the tropical, sub-humid climatic conditions should therefore be accompanied by entomologic studies to predict the risk of malaria epidemics.

Effects of Changes in Lugu Lake Water Quality on Schizothorax Yunnansis Ecological Habitat Based on HABITAT Model

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Huang, Wei; Mynnet, Arthur

Schizothorax Yunnansis is an unique fish species only existing in Lugu Lake, which is located in the southwestern China. The simulation and research on Schizothorax Yunnansis habitat environment have a vital significance to protect this rare fish. With the development of the tourism industry, there bring more pressure on the environmental protection. The living environment of Schizothorax Yunnansis is destroyed seriously because the water quality is suffering the sustaining pollution of domestic sewage from the peripheral villages. This paper analyzes the relationship between water quality change and Schizothorax Yunnansis ecological habitat and evalutes Schizothorax Yunnansis's ecological habitat impact based on HABITAT model. The results show that when the TP concentration in Lugu Lake does not exceed Schizothorax Yunnansis's survival threshold, Schizothorax Yunnansis can get more nutrients and the suitable habitat area for itself is increased. Conversely, it can lead to TP toxicity in the Schizothorax Yunnansis and even death. Therefore, unsuitable habitat area for Schizothorax Yunnansis is increased. It can be seen from the results that HABITAT model can assist in ecological impact assessment studies by translating results of hydrological, water quality models into effects on the natural environment and human society.

Predicting occurrence of juvenile shark habitat to improve conservation planning.

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Oh, Beverly Z L; Sequeira, Ana M M; Meekan, Mark G; Ruppert, Jonathan L W; Meeuwig, Jessica J

2017-06-01

Fishing and habitat degradation have increased the extinction risk of sharks, and conservation strategies recognize that survival of juveniles is critical for the effective management of shark populations. Despite the rapid expansion of marine protected areas (MPAs) globally, the paucity of shark-monitoring data on large scales (100s-1000s km) means that the effectiveness of MPAs in halting shark declines remains unclear. Using data collected by baited remote underwater video systems (BRUVS) in northwestern Australia, we developed generalized linear models to elucidate the ecological drivers of habitat suitability for juvenile sharks. We assessed occurrence patterns at the order and species levels. We included all juvenile sharks sampled and the 3 most abundant species sampled separately (grey reef [Carcharhinus amblyrhynchos], sandbar [Carcharhinus plumbeus], and whitetip reef sharks [Triaenodon obesus]). We predicted the occurrence of juvenile sharks across 490,515 km 2 of coastal waters and quantified the representation of highly suitable habitats within MPAs. Our species-level models had higher accuracy (ĸ ≥ 0.69) and deviance explained (≥48%) than our order-level model (ĸ = 0.36 and deviance explained of 10%). Maps of predicted occurrence revealed different species-specific patterns of highly suitable habitat. These differences likely reflect different physiological or resource requirements between individual species and validate concerns over the utility of conservation targets based on aggregate species groups as opposed to a species-focused approach. Highly suitable habitats were poorly represented in MPAs with the most restrictions on extractive activities. This spatial mismatch possibly indicates a lack of explicit conservation targets and information on species distribution during the planning process. Non-extractive BRUVS provided a useful platform for building the suitability models across large scales to assist conservation planning across

Habitat persistence for sedentary organisms in managed rivers: the case for the federally endangered dwarf wedgemussel (Alasmidonta heterodon) in the Delaware River

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Maloney, Kelly O.; Lellis, William A.; Bennett, Randy M.; Waddle, Terry J.

2012-01-01

1. To manage the environmental flow requirements of sedentary taxa, such as mussels and aquatic insects with fixed retreats, we need a measure of habitat availability over a variety of flows (i.e. a measure of persistent habitat). Habitat suitability measures in current environmental flow assessments are measured on a ‘flow by flow’ basis and thus are not appropriate for these taxa. Here, we present a novel measure of persistent habitat suitability for the dwarf wedgemussel (Alasmidonta heterodon), listed as federally endangered in the U.S.A., in three reaches of the Delaware River. 2. We used a two-dimensional hydrodynamic model to quantify suitable habitat over a range of flows based on modelled depth, velocity, Froude number, shear velocity and shear stress at three scales (individual mussel, mussel bed and reach). Baseline potentially persistent habitat was quantified as the sum of pixels that met all thresholds identified for these variables for flows ≥40 m3 s−1, and we calculated the loss of persistently suitable habitat by sequentially summing suitable habitat estimates at lower flows. We estimated the proportion of mussel beds exposed at each flow and the amount of change in the size of the mussel bed for one reach. 3. For two reaches, mussel beds occupied areas with lower velocity, shear velocity, shear stress and Froude number than the reach average at all flows. In the third reach, this was true only at higher flows. Together, these results indicate that beds were possible refuge areas from the effects of these hydrological parameters. Two reaches showed an increase in the amount of exposed mussel beds with decreasing flow. 4. Baseline potentially persistent habitat was less than half the areal extent of potentially suitable habitat, and it decreased with decreasing flow. Actually identified beds and modelled persistent habitat showed good spatial overlap, but identified beds occupied only a portion of the total modelled persistent

Physiology-based modelling approaches to characterize fish habitat suitability: Their usefulness and limitations

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Teal, Lorna R.; Marras, Stefano; Peck, Myron A.; Domenici, Paolo

2018-02-01

Models are useful tools for predicting the impact of global change on species distribution and abundance. As ectotherms, fish are being challenged to adapt or track changes in their environment, either in time through a phenological shift or in space by a biogeographic shift. Past modelling efforts have largely been based on correlative Species Distribution Models, which use known occurrences of species across landscapes of interest to define sets of conditions under which species are likely to maintain populations. The practical advantages of this correlative approach are its simplicity and the flexibility in terms of data requirements. However, effective conservation management requires models that make projections beyond the range of available data. One way to deal with such an extrapolation is to use a mechanistic approach based on physiological processes underlying climate change effects on organisms. Here we illustrate two approaches for developing physiology-based models to characterize fish habitat suitability. (i) Aerobic Scope Models (ASM) are based on the relationship between environmental factors and aerobic scope (defined as the difference between maximum and standard (basal) metabolism). This approach is based on experimental data collected by using a number of treatments that allow a function to be derived to predict aerobic metabolic scope from the stressor/environmental factor(s). This function is then integrated with environmental (oceanographic) data of current and future scenarios. For any given species, this approach allows habitat suitability maps to be generated at various spatiotemporal scales. The strength of the ASM approach relies on the estimate of relative performance when comparing, for example, different locations or different species. (ii) Dynamic Energy Budget (DEB) models are based on first principles including the idea that metabolism is organised in the same way within all animals. The (standard) DEB model aims to describe

Lowland tapir distribution and habitat loss in South America

Directory of Open Access Journals (Sweden)

Jose Luis Passos Cordeiro

2016-09-01

Full Text Available The development of species distribution models (SDMs can help conservation efforts by generating potential distributions and identifying areas of high environmental suitability for protection. Our study presents a distribution and habitat map for lowland tapir in South America. We also describe the potential habitat suitability of various geographical regions and habitat loss, inside and outside of protected areas network. Two different SDM approaches, MAXENT and ENFA, produced relative different Habitat Suitability Maps for the lowland tapir. While MAXENT was efficient at identifying areas as suitable or unsuitable, it was less efficient (when compared to the results by ENFA at identifying the gradient of habitat suitability. MAXENT is a more multifaceted technique that establishes more complex relationships between dependent and independent variables. Our results demonstrate that for at least one species, the lowland tapir, the use of a simple consensual approach (average of ENFA and MAXENT models outputs better reflected its current distribution patterns. The Brazilian ecoregions have the highest habitat loss for the tapir. Cerrado and Atlantic Forest account for nearly half (48.19% of the total area lost. The Amazon region contains the largest area under protection, and the most extensive remaining habitat for the tapir, but also showed high levels of habitat loss outside protected areas, which increases the importance of support for proper management.

Lowland tapir distribution and habitat loss in South America.

Science.gov (United States)

Cordeiro, Jose Luis Passos; Fragoso, José M V; Crawshaw, Danielle; Oliveira, Luiz Flamarion B

2016-01-01

The development of species distribution models (SDMs) can help conservation efforts by generating potential distributions and identifying areas of high environmental suitability for protection. Our study presents a distribution and habitat map for lowland tapir in South America. We also describe the potential habitat suitability of various geographical regions and habitat loss, inside and outside of protected areas network. Two different SDM approaches, MAXENT and ENFA, produced relative different Habitat Suitability Maps for the lowland tapir. While MAXENT was efficient at identifying areas as suitable or unsuitable, it was less efficient (when compared to the results by ENFA) at identifying the gradient of habitat suitability. MAXENT is a more multifaceted technique that establishes more complex relationships between dependent and independent variables. Our results demonstrate that for at least one species, the lowland tapir, the use of a simple consensual approach (average of ENFA and MAXENT models outputs) better reflected its current distribution patterns. The Brazilian ecoregions have the highest habitat loss for the tapir. Cerrado and Atlantic Forest account for nearly half (48.19%) of the total area lost. The Amazon region contains the largest area under protection, and the most extensive remaining habitat for the tapir, but also showed high levels of habitat loss outside protected areas, which increases the importance of support for proper management.

Red list assessment of European habitat types. A feasibility study

NARCIS (Netherlands)

Rodwell, J.S.; Janssen, J.A.M.; Gubbay, S.; Schaminee, J.H.J.

2013-01-01

This report presents an achievable methodology for the Red List assessment of European habitats in terrestrial, freshwater and marine realms, outlines a process that will deliver such evaluations and gives an indication of resources needed. It shows how the EUNIS habitat classification can be

Using multiscale spatial models to assess potential surrogate habitat for an imperiled reptile.

Directory of Open Access Journals (Sweden)

Jennifer M Fill

Full Text Available In evaluating conservation and management options for species, practitioners might consider surrogate habitats at multiple scales when estimating available habitat or modeling species' potential distributions based on suitable habitats, especially when native environments are rare. Species' dependence on surrogates likely increases as optimal habitat is degraded and lost due to anthropogenic landscape change, and thus surrogate habitats may be vital for an imperiled species' survival in highly modified landscapes. We used spatial habitat models to examine a potential surrogate habitat for an imperiled ambush predator (eastern diamondback rattlesnake, Crotalus adamanteus; EDB at two scales. The EDB is an apex predator indigenous to imperiled longleaf pine ecosystems (Pinus palustris of the southeastern United States. Loss of native open-canopy pine savannas and woodlands has been suggested as the principal cause of the species' extensive decline. We examined EDB habitat selection in the Coastal Plain tidewater region to evaluate the role of marsh as a potential surrogate habitat and to further quantify the species' habitat requirements at two scales: home range (HR and within the home range (WHR. We studied EDBs using radiotelemetry and employed an information-theoretic approach and logistic regression to model habitat selection as use vs.We failed to detect a positive association with marsh as a surrogate habitat at the HR scale; rather, EDBs exhibited significantly negative associations with all landscape patches except pine savanna. Within home range selection was characterized by a negative association with forest and a positive association with ground cover, which suggests that EDBs may use surrogate habitats of similar structure, including marsh, within their home ranges. While our HR analysis did not support tidal marsh as a surrogate habitat, marsh may still provide resources for EDBs at smaller scales.

Habitat hydraulic models - a tool for Danish stream quality assessment?

DEFF Research Database (Denmark)

Olsen, Martin

and hydromorphological and chemical characteristics has to be enlightened (EUROPA, 2005). This study links catchment hydrology, stream discharge and physical habitat in a small Danish stream, the stream Ledreborg, and discusses the utility of habitat hydraulic models in relation to the present criteria and methods used......).  Hydromorphological conditions in the stream are measured through field study, using a habitat mapping approach and modelled using a habitat hydraulic model (RHYHABSIM). Using RHYHABSIM and both "site-specific" and general HSI's, Weighted Usable Area (WUA) for the trout population at different discharges is assessed...... and differences between simulated WUA using "site-specific" and general habitat preferences are discussed. In RHYHABSIM it is possible to use two different approaches to investigate the hydromorphological conditions in a river, the habitat mapping approach used in this project and the representative reach...

Fitness consequences of habitat variability, trophic position, and energy allocation across the depth distribution of a coral-reef fish

Science.gov (United States)

Goldstein, E. D.; D'Alessandro, E. K.; Sponaugle, S.

2017-09-01

Environmental clines such as latitude and depth that limit species' distributions may be associated with gradients in habitat suitability that can affect the fitness of an organism. With the global loss of shallow-water photosynthetic coral reefs, mesophotic coral ecosystems ( 30-150 m) may be buffered from some environmental stressors, thereby serving as refuges for a range of organisms including mobile obligate reef dwellers. Yet habitat suitability may be diminished at the depth boundary of photosynthetic coral reefs. We assessed the suitability of coral-reef habitats across the majority of the depth distribution of a common demersal reef fish ( Stegastes partitus) ranging from shallow shelf (SS, restrict foraging. Fish in MP environments had a broader diet niche, higher trophic position, and higher muscle C:N ratios compared to shallower environments. High C:N ratios suggest increased tissue lipid content in fish in MP habitats that coincided with higher investment in reproduction based on gonado-somatic index. These results suggest that peripheral MP reefs are suitable habitats for demersal reef fish and may be important refuges for organisms common on declining shallow coral reefs.

Clear Creek Watershed Flood Risk Management Habitat Assessments Using Habitat Evaluation Procedures (HEP): Analyses, Results and Documentation

Science.gov (United States)

2013-07-01

Van der Molen , H. F. P. Van den Boogaard, and H. Van der Klis. 2006. Uncertainty analysis of a spatial habitat suitability model and implications...Brooks 1997, Brown et al. 2000, Store and Jokimaki 2003, Shifley et al. 2006, Van der Lee et al. 2006 and others). The Clear Creek study team made the...nature preserves (Brown et al. 2000, Ortigosa et al. 2000, Store and Kangas 2001, Felix et al. 2004, Ray and Burgman 2006, Van der Lee et al. 2006 and

Preliminary geological suitability assessment for LILW disposal

International Nuclear Information System (INIS)

Tomse, P.; Mele, I.

2001-01-01

Due to the growing need for a final disposal of LILW, the final solution for the short-lived LILW is the key issue of radioactive waste management in Slovenia at the moment. ARAO - the Slovenian Agency for Radwaste Management - is intensely involved in the re-initiated site selection process for a LILW repository. In this new process we are trying to combine as best as possible the technical, geologically-led and the advocacy-site selection processes. By a combination of technical and volunteer approach to the site selection we wish to guarantee high public involvement and sufficient flexibility of the process to adapt to specific conditions or new circumstances while the project is ongoing. In the technical phase, our tendency is to retain a larger number of potential areas/sites. We also keep open the possibility of choosing the type of repository. The decision between the surface and underground option will be made only once the site has been defined. In accordance with the IAEA recommendations the site selection process is divided into four stages: the conceptual and planning stage, area survey stage, site characterisation stage and site confirmation stage. Last year the area survey stage was started. In the preliminary geological suitability assessment the required natural predisposition of Slovene territory was assessed in order to locate geologically suitable formations. The assessment of natural conditions of the system was based on consideration of the main geological, hydro-geological and seismotectonic conditions. It was performed with ARC/INFO technology. The results are compiled in a map, showing potential areas for underground and surface disposal of LILW in Slovenia. It has been established that there is a potential suitability for both surface and underground disposal on about 10 000 km 2 of the Slovenian territory, which represents almost half of the entire Slovenian territory. These preliminary results are now being carefully re-examined. As an

An Assessment of the Population of Cotton-Top Tamarins (Saguinus oedipus and Their Habitat in Colombia.

Directory of Open Access Journals (Sweden)

Anne Savage

Full Text Available Numerous animals have declining populations due to habitat loss, illegal wildlife trade, and climate change. The cotton-top tamarin (Saguinus oedipus is a Critically Endangered primate species, endemic to northwest Colombia, threatened by deforestation and illegal trade. In order to assess the current state of this species, we analyzed changes in the population of cotton-top tamarins and its habitat from 2005 to 2012. We used a tailor-made "lure strip transect" method to survey 43 accessible forest parcels that represent 30% of the species' range. Estimated population size in the surveyed region was approximately 2,050 in 2005 and 1,900 in 2012, with a coefficient of variation of approximately 10%. The estimated population change between surveys was -7% (a decline of approximately 1.3% per year suggesting a relatively stable population. If densities of inaccessible forest parcels are similar to those of surveyed samples, the estimated population of cotton-top tamarins in the wild in 2012 was 6,946 individuals. We also recorded little change in the amount of suitable habitat for cotton-top tamarins between sample periods: in 2005, 18% of surveyed forest was preferred habitat for cotton-top tamarins, while in 2012, 17% percent was preferred. We attribute the relatively stable population of this Critically Endangered species to increased conservation efforts of Proyecto Tití, conservation NGOs, and the Colombian government. Due to continued threats to cotton-top tamarins and their habitat such as agriculture and urban expansion, ongoing conservation efforts are needed to ensure the long-term survival of cotton-top tamarins in Colombia.

Environmental predictors of habitat suitability and biogeographical range of Franciscana dolphins (Pontoporia blainvillei

Directory of Open Access Journals (Sweden)

Jonatan J. Gomez

2015-01-01

Full Text Available The aim of this study was to use species distribution models to estimate the effects of environmental variables on the habitat suitability of river dolphins Pontoporia blainvillei (franciscanas along their overall biogeographical distribution. Based on the literature, we selected six environmental variables to be included in the models; four climatic factors (surface sea temperature, salinity, turbidity and productivity and two biotic factors (prey availability and fishing effort. We determined that the biographic range is under the following limits: temperature less than 19°C, a salinity of 36 psu and a minimal probability of the occurrence of fish C. guatucupa of 0.297. In the discussion, we postulate hypotheses on the behavioural and physiological mechanisms that cause these associations between environmental predictors and Franciscanas distribution. There was a good fit between the distribution predicted by the species distribution model and the one proposed by the experts of the International Union for Conservation of Nature; however, our analysis failed to highlight the fundamental role of bycatch as the main threat to this dolphin species.

Modeling freshwater snail habitat suitability and areas of potential snail-borne disease transmission in Uganda

DEFF Research Database (Denmark)

Stensgaard, Anna-Sofie; Jørgensen, Aslak; Kabatereine, N B

2006-01-01

-borne disease transmission areas. Furthermore, knowledge of abiotic factors affecting intra-molluscan parasitic development can be used to make "masks" based on remotely sensed climatic data, and these can in turn be used to refine these predictions. We used data from a recent freshwater snail survey from......Geographic information system (GIS-based modeling of an intermediate host snail species environmental requirements using known occurrence records can provide estimates of its spatial distribution. When other data are lacking, this can be used as a rough spatial prediction of potential snail...... Uganda, environmental data and the genetic algorithm for rule-set prediction (GARP) to map the potential distribution of snail species known to act as intermediate hosts of several human and animal parasites. The results suggest that large areas of Uganda are suitable habitats for many of these snail...

Climate and air pollution impacts on habitat suitability of Austrian forest ecosystems.

NARCIS (Netherlands)

Dirnböck, Thomas; Djukic, Ika; Kitzler, Barbara; Kobler, Johannes; Mol-Dijkstra, Janet P; Posch, Max; Reinds, Gert Jan; Schlutow, Angela; Starlinger, Franz; Wamelink, Wieger G W

2017-01-01

Climate change and excess deposition of airborne nitrogen (N) are among the main stressors to floristic biodiversity. One particular concern is the deterioration of valuable habitats such as those protected under the European Habitat Directive. In future, climate-driven shifts (and losses) in the

Climate and air pollution impacts on habitat suitability of Austrian forest ecosystems

NARCIS (Netherlands)

Dirnböck, Thomas; Djukic, Ika; Kitzler, Barbara; Kobler, Johannes; Mol, Janet; Posch, Max; Reinds, Gert Jan; Schlutow, Angela; Starlinger, Franz; Wamelink, Wieger G.W.

2017-01-01

Climate change and excess deposition of airborne nitrogen (N) are among the main stressors to floristic biodiversity. One particular concern is the deterioration of valuable habitats such as those protected under the European Habitat Directive. In future, climate-driven shifts (and losses) in the

Land Suitability Assessment for Pineapple Production in the A ...

African Journals Online (AJOL)

linking land resources assessment to any land use decision-making process. like elsewhere, land ... managers as decision-support tools, for instance, to outline the most suitable land areas for subsidy ...... increase rational decisions. In this ..... essentially dynamic. it is pertinent that land suitability analysis is framed within an ...

Using maximum entropy to predict suitable habitat for the endangered dwarf wedgemussel in the Maryland Coastal Plain

Science.gov (United States)

Campbell, Cara; Hilderbrand, Robert H.

2017-01-01

Species distribution modelling can be useful for the conservation of rare and endangered species. Freshwater mussel declines have thinned species ranges producing spatially fragmented distributions across large areas. Spatial fragmentation in combination with a complex life history and heterogeneous environment makes predictive modelling difficult.A machine learning approach (maximum entropy) was used to model occurrences and suitable habitat for the federally endangered dwarf wedgemussel, Alasmidonta heterodon, in Maryland's Coastal Plain catchments. Landscape-scale predictors (e.g. land cover, land use, soil characteristics, geology, flow characteristics, and climate) were used to predict the suitability of individual stream segments for A. heterodon.The best model contained variables at three scales: minimum elevation (segment scale), percentage Tertiary deposits, low intensity development, and woody wetlands (sub-catchment), and percentage low intensity development, pasture/hay agriculture, and average depth to the water table (catchment). Despite a very small sample size owing to the rarity of A. heterodon, cross-validated prediction accuracy was 91%.Most predicted suitable segments occur in catchments not known to contain A. heterodon, which provides opportunities for new discoveries or population restoration. These model predictions can guide surveys toward the streams with the best chance of containing the species or, alternatively, away from those streams with little chance of containing A. heterodon.Developed reaches had low predicted suitability for A. heterodon in the Coastal Plain. Urban and exurban sprawl continues to modify stream ecosystems in the region, underscoring the need to preserve existing populations and to discover and protect new populations.

Fuzzy modelling of Atlantic salmon physical habitat

Science.gov (United States)

St-Hilaire, André; Mocq, Julien; Cunjak, Richard

2015-04-01

Fish habitat models typically attempt to quantify the amount of available river habitat for a given fish species for various flow and hydraulic conditions. To achieve this, information on the preferred range of values of key physical habitat variables (e.g. water level, velocity, substrate diameter) for the targeted fishs pecies need to be modelled. In this context, we developed several habitat suitability indices sets for three Atlantic salmon life stages (young-of-the-year (YOY), parr, spawning adults) with the help of fuzzy logic modeling. Using the knowledge of twenty-seven experts, from both sides of the Atlantic Ocean, we defined fuzzy sets of four variables (depth, substrate size, velocity and Habitat Suitability Index, or HSI) and associated fuzzy rules. When applied to the Romaine River (Canada), median curves of standardized Weighted Usable Area (WUA) were calculated and a confidence interval was obtained by bootstrap resampling. Despite the large range of WUA covered by the expert WUA curves, confidence intervals were relatively narrow: an average width of 0.095 (on a scale of 0 to 1) for spawning habitat, 0.155 for parr rearing habitat and 0.160 for YOY rearing habitat. When considering an environmental flow value corresponding to 90% of the maximum reached by WUA curve, results seem acceptable for the Romaine River. Generally, this proposed fuzzy logic method seems suitable to model habitat availability for the three life stages, while also providing an estimate of uncertainty in salmon preferences.

Linking population viability, habitat suitability, and landscape simulation models for conservation planning

Science.gov (United States)

Michael A. Larson; Frank R., III Thompson; Joshua J. Millspaugh; William D. Dijak; Stephen R. Shifley

2004-01-01

Methods for habitat modeling based on landscape simulations and population viability modeling based on habitat quality are well developed, but no published study of which we are aware has effectively joined them in a single, comprehensive analysis. We demonstrate the application of a population viability model for ovenbirds (Seiurus aurocapillus)...

Scenario-Led Habitat Modelling of Land Use Change Impacts on Key Species.

Directory of Open Access Journals (Sweden)

Matthew Geary

Full Text Available Accurate predictions of the impacts of future land use change on species of conservation concern can help to inform policy-makers and improve conservation measures. If predictions are spatially explicit, predicted consequences of likely land use changes could be accessible to land managers at a scale relevant to their working landscape. We introduce a method, based on open source software, which integrates habitat suitability modelling with scenario-building, and illustrate its use by investigating the effects of alternative land use change scenarios on landscape suitability for black grouse Tetrao tetrix. Expert opinion was used to construct five near-future (twenty years scenarios for the 800 km2 study site in upland Scotland. For each scenario, the cover of different land use types was altered by 5-30% from 20 random starting locations and changes in habitat suitability assessed by projecting a MaxEnt suitability model onto each simulated landscape. A scenario converting grazed land to moorland and open forestry was the most beneficial for black grouse, and 'increased grazing' (the opposite conversion the most detrimental. Positioning of new landscape blocks was shown to be important in some situations. Increasing the area of open-canopy forestry caused a proportional decrease in suitability, but suitability gains for the 'reduced grazing' scenario were nonlinear. 'Scenario-led' landscape simulation models can be applied in assessments of the impacts of land use change both on individual species and also on diversity and community measures, or ecosystem services. A next step would be to include landscape configuration more explicitly in the simulation models, both to make them more realistic, and to examine the effects of habitat placement more thoroughly. In this example, the recommended policy would be incentives on grazing reduction to benefit black grouse.

Assessing the impacts of river regulation on native bull trout (Salvelinus confluentus) and westslope cutthroat trout (Oncorhynchus clarkii lewisi) habitats in the upper Flathead River, Montana, USA

Science.gov (United States)

Muhlfeld, Clint C.; Jones, Leslie A.; Kotter, D.; Miller, William J.; Geise, Doran; Tohtz, Joel; Marotz, Brian

2012-01-01

Hungry Horse Dam on the South Fork Flathead River, Montana, USA, has modified the natural flow regimen for power generation, flood risk management and flow augmentation for anadromous fish recovery in the Columbia River. Concern over the detrimental effects of dam operations on native resident fishes prompted research to quantify the impacts of alternative flow management strategies on threatened bull trout (Salvelinus confluentus) and westslope cutthroat trout (Oncorhynchus clarkii lewisi) habitats. Seasonal and life‐stage specific habitat suitability criteria were combined with a two‐dimensional hydrodynamic habitat model to assess discharge effects on usable habitats. Telemetry data used to construct seasonal habitat suitability curves revealed that subadult (fish that emigrated from natal streams to the river system) bull trout move to shallow, low‐velocity shoreline areas at night, which are most sensitive to flow fluctuations. Habitat time series analyses comparing the natural flow regimen (predam, 1929–1952) with five postdam flow management strategies (1953–2008) show that the natural flow conditions optimize the critical bull trout habitats and that the current strategy best resembles the natural flow conditions of all postdam periods. Late summer flow augmentation for anadromous fish recovery, however, produces higher discharges than predam conditions, which reduces the availability of usable habitat during this critical growing season. Our results suggest that past flow management policies that created sporadic streamflow fluctuations were likely detrimental to resident salmonids and that natural flow management strategies will likely improve the chances of protecting key ecosystem processes and help to maintain and restore threatened bull trout and westslope cutthroat trout populations in the upper Columbia River Basin.

On Spatial Resolution in Habitat Models: Can Small-scale Forest Structure Explain Capercaillie Numbers?

Directory of Open Access Journals (Sweden)

Ilse Storch

2002-06-01

Full Text Available This paper explores the effects of spatial resolution on the performance and applicability of habitat models in wildlife management and conservation. A Habitat Suitability Index (HSI model for the Capercaillie (Tetrao urogallus in the Bavarian Alps, Germany, is presented. The model was exclusively built on non-spatial, small-scale variables of forest structure and without any consideration of landscape patterns. The main goal was to assess whether a HSI model developed from small-scale habitat preferences can explain differences in population abundance at larger scales. To validate the model, habitat variables and indirect sign of Capercaillie use (such as feathers or feces were mapped in six study areas based on a total of 2901 20 m radius (for habitat variables and 5 m radius sample plots (for Capercaillie sign. First, the model's representation of Capercaillie habitat preferences was assessed. Habitat selection, as expressed by Ivlev's electivity index, was closely related to HSI scores, increased from poor to excellent habitat suitability, and was consistent across all study areas. Then, habitat use was related to HSI scores at different spatial scales. Capercaillie use was best predicted from HSI scores at the small scale. Lowering the spatial resolution of the model stepwise to 36-ha, 100-ha, 400-ha, and 2000-ha areas and relating Capercaillie use to aggregated HSI scores resulted in a deterioration of fit at larger scales. Most importantly, there were pronounced differences in Capercaillie abundance at the scale of study areas, which could not be explained by the HSI model. The results illustrate that even if a habitat model correctly reflects a species' smaller scale habitat preferences, its potential to predict population abundance at larger scales may remain limited.

Predictive Modeling of Spinner Dolphin (Stenella longirostris) Resting Habitat in the Main Hawaiian Islands

Science.gov (United States)

Thorne, Lesley H.; Johnston, David W.; Urban, Dean L.; Tyne, Julian; Bejder, Lars; Baird, Robin W.; Yin, Suzanne; Rickards, Susan H.; Deakos, Mark H.; Mobley, Joseph R.; Pack, Adam A.; Chapla Hill, Marie

2012-01-01

Predictive habitat models can provide critical information that is necessary in many conservation applications. Using Maximum Entropy modeling, we characterized habitat relationships and generated spatial predictions of spinner dolphin (Stenella longirostris) resting habitat in the main Hawaiian Islands. Spinner dolphins in Hawai'i exhibit predictable daily movements, using inshore bays as resting habitat during daylight hours and foraging in offshore waters at night. There are growing concerns regarding the effects of human activities on spinner dolphins resting in coastal areas. However, the environmental factors that define suitable resting habitat remain unclear and must be assessed and quantified in order to properly address interactions between humans and spinner dolphins. We used a series of dolphin sightings from recent surveys in the main Hawaiian Islands and a suite of environmental variables hypothesized as being important to resting habitat to model spinner dolphin resting habitat. The model performed well in predicting resting habitat and indicated that proximity to deep water foraging areas, depth, the proportion of bays with shallow depths, and rugosity were important predictors of spinner dolphin habitat. Predicted locations of suitable spinner dolphin resting habitat provided in this study indicate areas where future survey efforts should be focused and highlight potential areas of conflict with human activities. This study provides an example of a presence-only habitat model used to inform the management of a species for which patterns of habitat availability are poorly understood. PMID:22937022

Diet, abundance and distribution as indices of turbot ( Psetta maxima L.) release habitat suitability

DEFF Research Database (Denmark)

Sparrevohn, Claus Reedtz; Støttrup, Josianne

2008-01-01

, natural abundance, and depth distribution within the habitats. A marked difference was found among habitats in the timing of the diet change from the suboptimal exoskeleton carrying prey items such as crustaceans to fish. The habitat where the wild turbot had the lowest occurrence of fish in their diet...

2004 assessment of habitat improvements in Dinosaur Reservoir

Energy Technology Data Exchange (ETDEWEB)

Blackman, B.G.; Cowie, D.M.

2005-01-15

Formed in 1979 after the completion of the Peace Canyon Dam, Dinosaur Reservoir is 21 km long and backs water up to the tailrace of W.A.C. Bennett Dam. BC Hydro has funded studies to evaluate fish stocking programs and assess habitat limitations and potential enhancements as part of a water licence agreement. The Peace/Williston Fish and Wildlife Compensation Programs (PWFWCP) have undertaken a number of projects to address fish habitat limitations, entrainment and stocking assessments as a result of recommendations stemming from these studies. It was determined that existing baseline fish data was needed in order to evaluate the effectiveness of these activities. A preliminary boat electro-fishing program which was started in October 2001, noted that a propensity for rainbow trout to concentrate near woody debris. In response, a program was started in 2002 to add woody debris to embayment areas throughout the reservoir. These enhanced woody debris structures are located in small sheltered bays and consist of a series of large trees cabled together and anchored to the shore. The area between the cabled trees and the shoreline is filled with woody debris and root wads collected from along the shoreline. The 2004 assessment of habitat improvements in Dinosaur Reservoir presents the findings from a study that compares the number of fish captured using trap nets, angling, and minnow traps, at the woody debris structures to sites with similar physical characteristics where woody debris had not been added. 17 refs., 5 tabs., 4 figs.

Combining catchment and instream modelling to assess physical habitat quality

DEFF Research Database (Denmark)

Olsen, Martin

Study objectives After the implementation of EU's Water Framework Directive (WFD) in Denmark ecological impacts from groundwater exploitation on surface waters has to receive additional consideration. Small streams in particular are susceptible to changes in run-off but have only recieved little...... attention in past studies of run-off impact on the quality of stream physical habitats. This study combined catchment and instream models with instream habitat observations to assess the ecological impacts from groundwater exploitation on a small stream. The main objectives of this study was; • to assess...... which factors are controlling the run-off conditions in stream Ledreborg and to what degree • to assess the run-off reference condition of stream Ledreborg where intensive groundwater abstraction has taken place in 67 years using a simple rainfall-run-off-model • to assess how stream run-off affect...

A preliminary assessment of the effectiveness of the Mesoamerican Biological Corridor for protecting potential Baird's tapir (Tapirus bairdii) habitat in Southern Mexico.

Science.gov (United States)

Mendoza, Eduardo; Fuller, Trevon L; Thomassen, Henri A; Buermann, Wolfgang; Ramírez-Mejía, Diana; Smith, Thomas B

2013-03-01

Baird's tapir (Tapirus bairdii) is one of the most emblematic mammals of Mesoamerica, but like other large-bodied animals, it is facing an increasing risk of extinction due primarily to habitat loss. Mexico's 'ortion of the Mesoamerican Biological Corridor (MBC-M) is located in one of the main strongholds for Bairds tapir. To assess the MBC-M's effectiveness for tapir conservation, we estimated the distribution of the species' potential habitat by applying 2 modelling approaches (random forest and Maxent) to a set of uncorrelated environmental variables and a 157-point presence dataset. We calculated the extent of tapir habitat in within the MBC-M and modelled new corridors and conservation areas, which we compared to the MBC-M. Moreover, we assessed deforestation patterns in the region. Twenty-seven percent of highly suitable tapir habitat occurred in protected areas, 15% in corridors and 58.3% was outside the MBC-M and associated reserves. The spatial configuration of the MBC-M was partially concordant with the modelled set of conservation areas and corridors. The main dissimilarity was that the modelled corridors traversed forests in Belize and Guatemala to connect conservation areas. Analyses of deforestation since 1993 and human population density in the vicinity of the MBC-M indicated that future conservation efforts should give particular attention to the Montes Azules-El Triunfo Corridor due to greater habitat threat. The MBC-M has a great potential to play a prominent role in the conservation of tapir habitat but there is an urgent need to implement management plans that reinforce and complement this conservation initiative. © 2012 Wiley Publishing Asia Pty Ltd, ISZS and IOZ/CAS.

Constructing Ecological Networks Based on Habitat Quality Assessment: A Case Study of Changzhou, China

Science.gov (United States)

Gao, Yu; Ma, Lei; Liu, Jiaxun; Zhuang, Zhuzhou; Huang, Qiuhao; Li, Manchun

2017-01-01

Fragmentation and reduced continuity of habitat patches threaten the environment and biodiversity. Recently, ecological networks are increasingly attracting the attention of researchers as they provide fundamental frameworks for environmental protection. This study suggests a set of procedures to construct an ecological network. First, we proposed a method to construct a landscape resistance surface based on the assessment of habitat quality. Second, to analyze the effect of the resistance surface on corridor simulations, we used three methods to construct resistance surfaces: (1) the method proposed in this paper, (2) the entropy coefficient method, and (3) the expert scoring method. Then, we integrated habitat patches and resistance surfaces to identify potential corridors using graph theory. These procedures were tested in Changzhou, China. Comparing the outputs of using different resistance surfaces demonstrated that: (1) different landscape resistance surfaces contribute to how corridors are identified, but only slightly affect the assessment of the importance of habitat patches and potential corridors; (2) the resistance surface, which is constructed based on habitat quality, is more applicable to corridor simulations; and (3) the assessment of the importance of habitat patches is fundamental for ecological network optimization in the conservation of critical habitat patches and corridors. PMID:28393879

Marine Benthic Habitats and Seabed Suitability Mapping for Potential Ocean Current Energy Siting Offshore Southeast Florida

Directory of Open Access Journals (Sweden)

Amanda Mulcan

2015-05-01

Full Text Available This study examines the legal framework for ocean current energy policy and regulation to develop a metric for assessing the biological and geological characteristics of a seabed area with respect to the siting of OCE devices, a framework of criteria by which to assess seabed suitability (seabed suitability framework that can facilitate the siting, and implementation of ocean current energy (OCE projects. Seafloor geology and benthic biological data were analyzed in conjunction with seafloor core sample geostatistical interpolation to locate suitable substrates for OCE anchoring. Existing submarine cable pathways were considered to determine pathways for power transmission cables that circumvent biologically sensitive areas. Suitability analysis indicates that areas east of the Miami Terrace and north of recently identified deep-sea coral mounds are the most appropriate for OCE siting due to abundance of sand/sediment substrate, existing underwater cable route access, and minimal biological presence (i.e., little to no benthic communities. Further reconnaissance requires higher resolution maps of geological substrate and benthic community locations to identify specific OCE development locations, classify benthic conditions, and minimize potentially negative OCE environmental impacts.

Global screening for Critical Habitat in the terrestrial realm.

Science.gov (United States)

Brauneder, Kerstin M; Montes, Chloe; Blyth, Simon; Bennun, Leon; Butchart, Stuart H M; Hoffmann, Michael; Burgess, Neil D; Cuttelod, Annabelle; Jones, Matt I; Kapos, Val; Pilgrim, John; Tolley, Melissa J; Underwood, Emma C; Weatherdon, Lauren V; Brooks, Sharon E

2018-01-01

Critical Habitat has become an increasingly important concept used by the finance sector and businesses to identify areas of high biodiversity value. The International Finance Corporation (IFC) defines Critical Habitat in their highly influential Performance Standard 6 (PS6), requiring projects in Critical Habitat to achieve a net gain of biodiversity. Here we present a global screening layer of Critical Habitat in the terrestrial realm, derived from global spatial datasets covering the distributions of 12 biodiversity features aligned with guidance provided by the IFC. Each biodiversity feature is categorised as 'likely' or 'potential' Critical Habitat based on: 1. Alignment between the biodiversity feature and the IFC Critical Habitat definition; and 2. Suitability of the spatial resolution for indicating a feature's presence on the ground. Following the initial screening process, Critical Habitat must then be assessed in-situ by a qualified assessor. This analysis indicates that a total of 10% and 5% of the global terrestrial environment can be considered as likely and potential Critical Habitat, respectively, while the remaining 85% did not overlap with any of the biodiversity features assessed and was classified as 'unknown'. Likely Critical Habitat was determined principally by the occurrence of Key Biodiversity Areas and Protected Areas. Potential Critical Habitat was predominantly characterised by data representing highly threatened and unique ecosystems such as ever-wet tropical forests and tropical dry forests. The areas we identified as likely or potential Critical Habitat are based on the best available global-scale data for the terrestrial realm that is aligned with IFC's Critical Habitat definition. Our results can help businesses screen potential development sites at the early project stage based on a range of biodiversity features. However, the study also demonstrates several important data gaps and highlights the need to incorporate new and

Integrating animal movement with habitat suitability for estimating dynamic landscape connectivity

Science.gov (United States)

van Toor, Mariëlle L.; Kranstauber, Bart; Newman, Scott H.; Prosser, Diann J.; Takekawa, John Y.; Technitis, Georgios; Weibel, Robert; Wikelski, Martin; Safi, Kamran

2018-01-01

Context High-resolution animal movement data are becoming increasingly available, yet having a multitude of empirical trajectories alone does not allow us to easily predict animal movement. To answer ecological and evolutionary questions at a population level, quantitative estimates of a species’ potential to link patches or populations are of importance. Objectives We introduce an approach that combines movement-informed simulated trajectories with an environment-informed estimate of the trajectories’ plausibility to derive connectivity. Using the example of bar-headed geese we estimated migratory connectivity at a landscape level throughout the annual cycle in their native range. Methods We used tracking data of bar-headed geese to develop a multi-state movement model and to estimate temporally explicit habitat suitability within the species’ range. We simulated migratory movements between range fragments, and calculated a measure we called route viability. The results are compared to expectations derived from published literature. Results Simulated migrations matched empirical trajectories in key characteristics such as stopover duration. The viability of the simulated trajectories was similar to that of the empirical trajectories. We found that, overall, the migratory connectivity was higher within the breeding than in wintering areas, corroborating previous findings for this species. Conclusions We show how empirical tracking data and environmental information can be fused for meaningful predictions of animal movements throughout the year and even outside the spatial range of the available data. Beyond predicting migratory connectivity, our framework will prove useful for modelling ecological processes facilitated by animal movement, such as seed dispersal or disease ecology.

Comparing GIS-based habitat models for applications in EIA and SEA

International Nuclear Information System (INIS)

Gontier, Mikael; Moertberg, Ulla; Balfors, Berit

2010-01-01

Land use changes, urbanisation and infrastructure developments in particular, cause fragmentation of natural habitats and threaten biodiversity. Tools and measures must be adapted to assess and remedy the potential effects on biodiversity caused by human activities and developments. Within physical planning, environmental impact assessment (EIA) and strategic environmental assessment (SEA) play important roles in the prediction and assessment of biodiversity-related impacts from planned developments. However, adapted prediction tools to forecast and quantify potential impacts on biodiversity components are lacking. This study tested and compared four different GIS-based habitat models and assessed their relevance for applications in environmental assessment. The models were implemented in the Stockholm region in central Sweden and applied to data on the crested tit (Parus cristatus), a sedentary bird species of coniferous forest. All four models performed well and allowed the distribution of suitable habitats for the crested tit in the Stockholm region to be predicted. The models were also used to predict and quantify habitat loss for two regional development scenarios. The study highlighted the importance of model selection in impact prediction. Criteria that are relevant for the choice of model for predicting impacts on biodiversity were identified and discussed. Finally, the importance of environmental assessment for the preservation of biodiversity within the general frame of biodiversity conservation is emphasised.

Evaluation of osprey habitat suitability and interaction with contaminant exposure

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Toschik, P.C.; Christman, M.C.; Rattner, B.A.; Ottinger, M.A.

2006-01-01

Ospreys (Pandion haliaetus) have been the focus of conservation efforts since their dramatic population decline attributed to dichlorodiphenyltrichloroethane and related chemicals in the 1960s. Several recent studies of ospreys nesting in the United States have indicated improved reproduction. However, the density of breeding ospreys varies greatly among locations, with some areas seemingly habitable but not occupied. Because of concerns about pollution in the highly industrialized portions of the Delaware River and Bay, USA, we evaluated contaminant exposure and productivity in ospreys nesting on the Delaware River and Bay in 2002. We characterized habitat in the coastal zone of Delaware, USA, and the area around the river in Pennsylvania, USA, using data we collected as well as extant information provided by state and federal sources. We characterized habitat based on locations of occupied osprey nests in Delaware and Pennsylvania. We evaluated water clarity, water depth, land use and land cover, nest availability, and contaminants in sediment for use in a nest-occupancy model. Our results demonstrated that the presence of occupied nests was associated with water depth, water clarity, distance to an occupied osprey nest, and presence of urban land use, whereas a companion study demonstrated that hatching success was associated with the principal components derived from organochlorine-contaminant concentrations in osprey eggs (total polychlorinated biphenyls, p,p'-dichlorodiphenylethylene, chlordane and metabolites, and heptachlor epoxide). Our study provides guidelines for resource managers and local conservation organizations in management of ospreys and in development of habitat models that are appropriate for other piscivorous and marsh-nesting birds.

Host habitat assessment by a parasitoid using fungal volatiles

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Steidle Johannes LM

2007-02-01

Full Text Available Abstract Background The preference – performance hypothesis predicts that oviposition preference of insects should correlate with host suitability for offspring development. Therefore, insect females have to be able to assess not only the quality of a given host but also the environmental conditions of the respective host habitat. Chemical cues are a major source of information used by insects for this purpose. Primary infestation of stored grain by stored product pests often favors the intense growth of mold. This can lead to distinct sites of extreme environmental conditions (hot-spots with increased insect mortality. We studied the influence of mold on chemical orientation, host recognition, and fitness of Lariophagus distinguendus, a parasitoid of beetle larvae developing in stored grain. Results Volatiles of wheat infested by Aspergillus sydowii and A. versicolor repelled female parasitoids in an olfactometer. Foraging L. distinguendus females are known to be strongly attracted to the odor of larval host feces from the granary weevil Sitophilus granarius, which may adhere in remarkable amounts to the surface of the grains. Feces from moldy weevil cultures elicited neutral responses but parasitoids clearly avoided moldy feces when non-moldy feces were offered simultaneously. The common fungal volatile 1-octen-3-ol was the major component of the odor of larval feces from moldy weevil cultures and repelled female parasitoids at naturally occurring doses. In bioassays investigating host recognition behavior of L. distinguendus, females spent less time on grains containing hosts from moldy weevil cultures and showed less drumming and drilling behavior than on non-moldy controls. L. distinguendus had a clearly reduced fitness on hosts from moldy weevil cultures. Conclusion We conclude that L. distinguendus females use 1-octen-3-ol for host habitat assessment to avoid negative fitness consequences due to secondary mold infestation of host

Habitat assessment of non-wadeable rivers in Michigan.

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Wilhelm, Jennifer G O; Allan, J David; Wessell, Kelly J; Merritt, Richard W; Cummins, Kenneth W

2005-10-01

Habitat evaluation of wadeable streams based on accepted protocols provides a rapid and widely used adjunct to biological assessment. However, little effort has been devoted to habitat evaluation in non-wadeable rivers, where it is likely that protocols will differ and field logistics will be more challenging. We developed and tested a non-wadeable habitat index (NWHI) for rivers of Michigan, where non-wadeable rivers were defined as those of order >or=5, drainage area >or=1600 km2, mainstem lengths >or=100 km, and mean annual discharge >or=15 m3/s. This identified 22 candidate rivers that ranged in length from 103 to 825 km and in drainage area from 1620 to 16,860 km2. We measured 171 individual habitat variables over 2-km reaches at 35 locations on 14 rivers during 2000-2002, where mean wetted width was found to range from 32 to 185 m and mean thalweg depth from 0.8 to 8.3 m. We used correlation and principal components analysis to reduce the number of variables, and examined the spatial pattern of retained variables to exclude any that appeared to reflect spatial location rather than reach condition, resulting in 12 variables to be considered in the habitat index. The proposed NWHI included seven variables: riparian width, large woody debris, aquatic vegetation, bottom deposition, bank stability, thalweg substrate, and off-channel habitat. These variables were included because of their statistical association with independently derived measures of human disturbance in the riparian zone and the catchment, and because they are considered important in other habitat protocols or to the ecology of large rivers. Five variables were excluded because they were primarily related to river size rather than anthropogenic disturbance. This index correlated strongly with indices of disturbance based on the riparian (adjusted R2 = 0.62) and the catchment (adjusted R2 = 0.50), and distinguished the 35 river reaches into the categories of poor (2), fair (19), good (13), and

Daytime habitat selection for juvenile parr brown trout (Salmo trutta) in small lowland streams

DEFF Research Database (Denmark)

Conallin, J.; Boegh, E.; Olsen, M.

2014-01-01

Physical habitat is important in determining the carrying capacity of juvenile brown trout, and within freshwater management. Summer daytime physical habitat selection for the parr lifestage (7-20 cm) juvenile brown trout (Salmo trutta) was assessed in 6 small lowland streams. Habitat preference...... was determined for the four variables; water velocity, water depth, substrate and cover, and the preferences for physical habitat selection were expressed in terms of habitat suitability indices (HSI's). The statistical confidence of HSI's was evaluated using power analysis. It was found that a minimum of 22...... fish observations was needed to have statistical confidence in the HSIs for water depth, and a minimum of 92 fish observations for water velocity during daytime summer conditions. Generally parr were utilising the deeper habitats, indicating preference for deeper water. Cover was also being selected...

Eco-hydrologic model cascades: Simulating land use and climate change impacts on hydrology, hydraulics and habitats for fish and macroinvertebrates.

Science.gov (United States)

Guse, Björn; Kail, Jochem; Radinger, Johannes; Schröder, Maria; Kiesel, Jens; Hering, Daniel; Wolter, Christian; Fohrer, Nicola

2015-11-15

Climate and land use changes affect the hydro- and biosphere at different spatial scales. These changes alter hydrological processes at the catchment scale, which impact hydrodynamics and habitat conditions for biota at the river reach scale. In order to investigate the impact of large-scale changes on biota, a cascade of models at different scales is required. Using scenario simulations, the impact of climate and land use change can be compared along the model cascade. Such a cascade of consecutively coupled models was applied in this study. Discharge and water quality are predicted with a hydrological model at the catchment scale. The hydraulic flow conditions are predicted by hydrodynamic models. The habitat suitability under these hydraulic and water quality conditions is assessed based on habitat models for fish and macroinvertebrates. This modelling cascade was applied to predict and compare the impacts of climate- and land use changes at different scales to finally assess their effects on fish and macroinvertebrates. Model simulations revealed that magnitude and direction of change differed along the modelling cascade. Whilst the hydrological model predicted a relevant decrease of discharge due to climate change, the hydraulic conditions changed less. Generally, the habitat suitability for fish decreased but this was strongly species-specific and suitability even increased for some species. In contrast to climate change, the effect of land use change on discharge was negligible. However, land use change had a stronger impact on the modelled nitrate concentrations affecting the abundances of macroinvertebrates. The scenario simulations for the two organism groups illustrated that direction and intensity of changes in habitat suitability are highly species-dependent. Thus, a joined model analysis of different organism groups combined with the results of hydrological and hydrodynamic models is recommended to assess the impact of climate and land use changes on

Asian elephants in China: estimating population size and evaluating habitat suitability.

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Li Zhang

Full Text Available We monitored the last remaining Asian elephant populations in China over the past decade. Using DNA tools and repeat genotyping, we estimated the population sizes from 654 dung samples collected from various areas. Combined with morphological individual identifications from over 6,300 elephant photographs taken in the wild, we estimated that the total Asian elephant population size in China is between 221 and 245. Population genetic structure and diversity were examined using a 556-bp fragment of mitochondrial DNA, and 24 unique haplotypes were detected from DNA analysis of 178 individuals. A phylogenetic analysis revealed two highly divergent clades of Asian elephants, α and β, present in Chinese populations. Four populations (Mengla, Shangyong, Mengyang, and Pu'Er carried mtDNA from the α clade, and only one population (Nangunhe carried mtDNA belonging to the β clade. Moreover, high genetic divergence was observed between the Nangunhe population and the other four populations; however, genetic diversity among the five populations was low, possibly due to limited gene flow because of habitat fragmentation. The expansion of rubber plantations, crop cultivation, and villages along rivers and roads had caused extensive degradation of natural forest in these areas. This had resulted in the loss and fragmentation of elephant habitats and had formed artificial barriers that inhibited elephant migration. Using Geographic Information System, Global Positioning System, and Remote Sensing technology, we found that the area occupied by rubber plantations, tea farms, and urban settlements had dramatically increased over the past 40 years, resulting in the loss and fragmentation of elephant habitats and forming artificial barriers that inhibit elephant migration. The restoration of ecological corridors to facilitate gene exchange among isolated elephant populations and the establishment of cross-boundary protected areas between China and Laos to secure

Suitability of voltage stability study methods for real-time assessment

DEFF Research Database (Denmark)

Perez, Angel; Jóhannsson, Hjörtur; Vancraeyveld, Pieter

2013-01-01

This paper analyzes the suitability of existing methods for long-term voltage stability assessment for real-time operation. An overview of the relevant methods is followed with a comparison that takes into account the accuracy, computational efficiency and characteristics when used for security...... assessment. The results enable an evaluation of the run time of each method with respect to the number of inputs. Furthermore, the results assist in identifying which of the methods is most suitable for realtime operation in future power system with production based on fluctuating energy sources....

Spatially explicit feedbacks between seagrass meadow structure, sediment and light: Habitat suitability for seagrass growth

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Carr, Joel; D'Odorico, Paul; McGlathery, Karen; Wiberg, Patricia L.

2016-01-01

In shallow coastal bays where nutrient loading and riverine inputs are low, turbidity, and the consequent light environment are controlled by resuspension of bed sediments due to wind-waves and tidal currents. High sediment resuspension and low light environments can limit benthic primary productivity; however, both currents and waves are affected by the presence of benthic plants such as seagrass. This feedback between the presence of benthic primary producers such as seagrass and the consequent light environment has been predicted to induce bistable dynamics locally. However, these vegetated areas influence a larger area than they footprint, including a barren adjacent downstream area which exhibits reduced shear stresses. Here we explore through modeling how the patchy structure of seagrass meadows on a landscape may affect sediment resuspension and the consequent light environment due to the presence of this sheltered region. Heterogeneous vegetation covers comprising a mosaic of randomly distributed patches were generated to investigate the effect of patch modified hydrodynamics. Actual cover of vegetation on the landscape was used to facilitate comparisons across landscape realizations. Hourly wave and current shear stresses on the landscape along with suspended sediment concentration and light attenuation characteristics were then calculated and spatially averaged to examine how actual cover and mean water depth affect the bulk sediment and light environment. The results indicate that an effective cover, which incorporates the sheltering area, has important controls on the distributions of shear stress, suspended sediment, light environment, and consequent seagrass habitat suitability. Interestingly, an optimal habitat occurs within a depth range where, if actual cover is reduced past some threshold, the bulk light environment would no longer favor seagrass growth.

Field Validation of Habitat Suitability Models for Vulnerable Marine Ecosystems in the South Pacific Ocean: Implications for the use of Broad-scale Models in Fisheries Management

Science.gov (United States)

Anderson, O. F.; Guinotte, J. M.; Clark, M. R.; Rowden, A. A.; Mormede, S.; Davies, A. J.; Bowden, D.

2016-02-01

Spatial management of vulnerable marine ecosystems requires accurate knowledge of their distribution. Predictive habitat suitability modelling, using species presence data and a suite of environmental predictor variables, has emerged as a useful tool for inferring distributions outside of known areas. However, validation of model predictions is typically performed with non-independent data. In this study, we describe the results of habitat suitability models constructed for four deep-sea reef-forming coral species across a large region of the South Pacific Ocean using MaxEnt and Boosted Regression Tree modelling approaches. In order to validate model predictions we conducted a photographic survey on a set of seamounts in an un-sampled area east of New Zealand. The likelihood of habitat suitable for reef forming corals on these seamounts was predicted to be variable, but very high in some regions, particularly where levels of aragonite saturation, dissolved oxygen, and particulate organic carbon were optimal. However, the observed frequency of coral occurrence in analyses of survey photographic data was much lower than expected, and patterns of observed versus predicted coral distribution were not highly correlated. The poor performance of these broad-scale models is attributed to lack of recorded species absences to inform the models, low precision of global bathymetry models, and lack of data on the geomorphology and substrate of the seamounts at scales appropriate to the modelled taxa. This demonstrates the need to use caution when interpreting and applying broad-scale, presence-only model results for fisheries management and conservation planning in data poor areas of the deep sea. Future improvements in the predictive performance of broad-scale models will rely on the continued advancement in modelling of environmental predictor variables, refinements in modelling approaches to deal with missing or biased inputs, and incorporation of true absence data.

Habitat and hydrology: assessing biological resources of the Suwannee River Estuarine System

Science.gov (United States)

Raabe, Ellen A.; Edwards, Randy E.; McIvor, Carole C.; Grubbs, Jack W.; Dennis, George D.

2007-01-01

hydrologic data identified a range of habitat characteristics and differences in tidal-creek morphology. This endeavor related nearshore benthic habitat and hydrologic conditions with habitat suitability and fish assemblages and provides a template for similar applications in shallow and nearshore estuarine environments.

Abundance and Distribution Patterns of Thunnus albacares in Isla del Coco National Park through Predictive Habitat Suitability Models.

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Cristina Gonzáles-Andrés

Full Text Available Information on the distribution and habitat preferences of ecologically and commercially important species is essential for their management and protection. This is especially important as climate change, pollution, and overfishing change the structure and functioning of pelagic ecosystems. In this study, we used Bayesian hierarchical spatial-temporal models to map the Essential Fish Habitats of the Yellowfin tuna (Thunnus albacares in the waters around Isla del Coco National Park, Pacific Costa Rica, based on independent underwater observations from 1993 to 2013. We assessed if observed changes in the distribution and abundance of this species are related with habitat characteristics, fishing intensity or more extreme climatic events, including the El Niño Southern Oscillation, and changes on the average sea surface temperature. Yellowfin tuna showed a decreasing abundance trend in the sampled period, whereas higher abundances were found in shallow and warmer waters, with high concentration of chlorophyll-a, and in surrounding seamounts. In addition, El Niño Southern Oscillation events did not seem to affect Yellowfin tuna distribution and abundance. Understanding the habitat preferences of this species, using approaches as the one developed here, may help design integrated programs for more efficient management of vulnerable species.

EXPERT MODEL OF LAND SUITABILITY ASSESSMENT FOR CROPS

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Boris Đurđević

2010-12-01

Full Text Available A total of 17404 soil samples (2003rd-2009th year were analysed in the eastern Croatia. The largest number of soil samples belongs to the Osijek-Baranya county, which together with both Eastern sugar beet Factories (Osijek and Županja, conduct the soil fertility control (~4200 samples/yr.. Computer model suitability assessment for crops, supported by GIS, proved to be fast, efficient enough reliable in terms of the number of analyzed soil samples. It allows the visualization of the agricultural area and prediction of its production properties for the purposes of analysis, planning and rationalization of agricultural production. With more precise data about the soil (soil, climate and reliable Digital Soil Map of Croatia, the model could be an acceptable, not only to evaluate the suitability for growing different crops but also their need for fertilizer, necessary machinery, repairs (liming, and other measures of organic matter input. The abovementioned aims to eliminate or reduce effects of limiting factors in primary agricultural production. Assessment of the relative benefits of soil presented by computer model for the crops production and geostatistical method kriging in the Osijek-Baranya county showed: 1 Average soil suitability being 60.06 percent. 2 Kriging predicted that 51751 ha (17.16% are of limited resources (N1 for growing crops whereas a 86142 ha (28.57% of land is limited suitably (S3, b 132789 ha (44.04% are moderately suitable (S2 and c 30772 ha (10.28% are of excellent fertility (S1. A large number of eastern Croatian land data showed that the computer-geostatistical model for determination of soil benefits for growing crops was automated, fast and simple to use and suitable for the implementation of GIS and automatically downloading the necessary benefit indicators from the input base (land, analytical and climate as well as data from the digital soil maps able to: a visualize the suitability for soil tillage, b predict the

Modeling Habitat Suitability of Migratory Birds from Remote Sensing Images Using Convolutional Neural Networks.

Science.gov (United States)

Su, Jin-He; Piao, Ying-Chao; Luo, Ze; Yan, Bao-Ping

2018-04-26

With the application of various data acquisition devices, a large number of animal movement data can be used to label presence data in remote sensing images and predict species distribution. In this paper, a two-stage classification approach for combining movement data and moderate-resolution remote sensing images was proposed. First, we introduced a new density-based clustering method to identify stopovers from migratory birds’ movement data and generated classification samples based on the clustering result. We split the remote sensing images into 16 × 16 patches and labeled them as positive samples if they have overlap with stopovers. Second, a multi-convolution neural network model is proposed for extracting the features from temperature data and remote sensing images, respectively. Then a Support Vector Machines (SVM) model was used to combine the features together and predict classification results eventually. The experimental analysis was carried out on public Landsat 5 TM images and a GPS dataset was collected on 29 birds over three years. The results indicated that our proposed method outperforms the existing baseline methods and was able to achieve good performance in habitat suitability prediction.

Two-dimensional physical habitat modeling of effects of habitat structures on urban stream restoration

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Dongkyun Im

2011-12-01

Full Text Available River corridors, even if highly modified or degraded, still provide important habitats for numerous biological species, and carry high aesthetic and economic values. One of the keys to urban stream restoration is recovery and maintenance of ecological flows sufficient to sustain aquatic ecosystems. In this study, the Hongje Stream in the Seoul metropolitan area of Korea was selected for evaluating a physically-based habitat with and without habitat structures. The potential value of the aquatic habitat was evaluated by a weighted usable area (WUA using River2D, a two-dimensional hydraulic model. The habitat suitability for Zacco platypus in the Hongje Stream was simulated with and without habitat structures. The computed WUA values for the boulder, spur dike, and riffle increased by about 2%, 7%, and 131%, respectively, after their construction. Also, the three habitat structures, especially the riffle, can contribute to increasing hydraulic heterogeneity and enhancing habitat diversity.

Agricultural utilisation and potential suitability of the Sysľovské polia Special Protection Area (south-western Slovakia landscape in relation to the habitat requirements of the red-footed falcon (Falco vespertinus

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Zemko Martin

2017-12-01

Full Text Available Intensification of land use in an agricultural landscape significantly affects biodiversity also in protected areas. This can be observed in the Sysľovské polia Special Protection Area in relation to the occurrence of the red-footed falcon (Falco vespertinus. The objective of this study was to evaluate the landscape structure and suitability of agrotechnical procedures for the habitat demands of this species in the course of the period from 2004 until 2017. The utilisation was assessed on the basis of four landscape elements representation in 1949 and 2017. The next step was analysis of landscape patches. The aim was to quantify the diversity and the spatial structure of the landscape mosaic using Shannon’s Diversity Index and Evenness Index as well as Simpson’s Diversity Index and Evenness Index and spatial pattern analysis in the Fragstats software programme. Assessment of crop suitability was carried out according to the following criteria: representation of positive/negative agricultural crops, diversity of crops in crop rotation, and (non-observance of crop rotation. It was found that the agricultural landscape use did not change significantly. The study area has been used as an intensively-farmed agricultural landscape for a long time. The landscape elements have remained almost identical, with dominance of arable land. Differences emerged in the analysis of the micropatches, which are represented by natural hedgerows consisting of various species of trees, shrubs and grasses. The results show a decrease in the diversity of patches and changes in the structure of the landscape patches, which may be important in terms of the preservation of the habitat of fauna which form an important part of the F vespertinus diet. On the basis of the evaluation of the suitability of agricultural crop growing, we found that there were some areas showing negative values in all the criteria, and thus they require changes in the crop rotation focusing

Monitoring Natura 2000 habitats: habitat 92A0 in central Italy as an example

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Emanuela Carli

2016-10-01

Full Text Available The evaluation and the subsequent monitoring of the conservation status of habitats is one of the key steps in nature protection. While some European countries have tested suitable methodologies, others, including Italy, lack procedures tested at the national level. The aim of this work is to propose a method to assess the conservation status of habitat 92A0 (Salix alba and Populus alba galleries in central Italy, and to test the method using data from the Molise region. We selected parameters that highlight the conservation status of the flora and vegetation in order to assess habitat structures and functions at the site level. After selecting the parameters, we tested them on a training dataset of 22 unpublished phytosociological relevés taken from the whole dataset, which consists of 119 relevés (49 unpublished relevés for the study area, and 70 published relevés for central Italy. We detected the most serious conservation problems in the middle and lower course of the Biferno river: the past use of river terraces for agriculture and continual human interventions on the river water flow have drastically reduced the riparian forests of Molise. Our results show that in areas in which forest structure and floristic composition have been substantially modified, certain alien plant species, particularly Robinia pseudoacacia, Amorpha fruticosa and Erigeron canadensis, have spread extensively along rivers. In the management of riparian forests, actions aimed at maintaining the stratification of the forest, its uneven-agedness and tree species richness may help to ensure the conservation status, as well as favour the restoration, of habitat 92A0.

Riverine habitat dynamics

Science.gov (United States)

Jacobson, R.B.

2013-01-01

The physical habitat template is a fundamental influence on riverine ecosystem structure and function. Habitat dynamics refers to the variation in habitat through space and time as the result of varying discharge and varying geomorphology. Habitat dynamics can be assessed at spatial scales ranging from the grain (the smallest resolution at which an organism relates to its environment) to the extent (the broadest resolution inclusive of all space occupied during its life cycle). In addition to a potentially broad range of spatial scales, assessments of habitat dynamics may include dynamics of both occupied and nonoccupied habitat patches because of process interactions among patches. Temporal aspects of riverine habitat dynamics can be categorized into hydrodynamics and morphodynamics. Hydrodynamics refers to habitat variation that results from changes in discharge in the absence of significant change of channel morphology and at generally low sediment-transport rates. Hydrodynamic assessments are useful in cases of relatively high flow exceedance (percent of time a flow is equaled or exceeded) or high critical shear stress, conditions that are applicable in many studies of instream flows. Morphodynamics refers to habitat variation resulting from changes to substrate conditions or channel/floodplain morphology. Morphodynamic assessments are necessary when channel and floodplain boundary conditions have been significantly changed, generally by relatively rare flood events or in rivers with low critical shear stress. Morphodynamic habitat variation can be particularly important as disturbance mechanisms that mediate population growth or for providing conditions needed for reproduction, such as channel-migration events that erode cutbanks and provide new pointbar surfaces for germination of riparian trees. Understanding of habitat dynamics is increasing in importance as societal goals shift toward restoration of riverine ecosystems. Effective investment in restoration

Spatial Scaling of Environmental Variables Improves Species-Habitat Models of Fishes in a Small, Sand-Bed Lowland River.

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Johannes Radinger

Full Text Available Habitat suitability and the distinct mobility of species depict fundamental keys for explaining and understanding the distribution of river fishes. In recent years, comprehensive data on river hydromorphology has been mapped at spatial scales down to 100 m, potentially serving high resolution species-habitat models, e.g., for fish. However, the relative importance of specific hydromorphological and in-stream habitat variables and their spatial scales of influence is poorly understood. Applying boosted regression trees, we developed species-habitat models for 13 fish species in a sand-bed lowland river based on river morphological and in-stream habitat data. First, we calculated mean values for the predictor variables in five distance classes (from the sampling site up to 4000 m up- and downstream to identify the spatial scale that best predicts the presence of fish species. Second, we compared the suitability of measured variables and assessment scores related to natural reference conditions. Third, we identified variables which best explained the presence of fish species. The mean model quality (AUC = 0.78, area under the receiver operating characteristic curve significantly increased when information on the habitat conditions up- and downstream of a sampling site (maximum AUC at 2500 m distance class, +0.049 and topological variables (e.g., stream order were included (AUC = +0.014. Both measured and assessed variables were similarly well suited to predict species' presence. Stream order variables and measured cross section features (e.g., width, depth, velocity were best-suited predictors. In addition, measured channel-bed characteristics (e.g., substrate types and assessed longitudinal channel features (e.g., naturalness of river planform were also good predictors. These findings demonstrate (i the applicability of high resolution river morphological and instream-habitat data (measured and assessed variables to predict fish presence, (ii the

Remote sensing-based landscape indicators for the evaluation of threatened-bird habitats in a tropical forest.

Science.gov (United States)

Singh, Minerva; Tokola, Timo; Hou, Zhengyang; Notarnicola, Claudia

2017-07-01

Avian species persistence in a forest patch is strongly related to the degree of isolation and size of a forest patch and the vegetation structure within a patch and its matrix are important predictors of bird habitat suitability. A combination of space-borne optical (Landsat), ALOS-PALSAR (radar), and airborne Light Detection and Ranging (LiDAR) data was used for assessing variation in forest structure across forest patches that had undergone different levels of forest degradation in a logged forest-agricultural landscape in Southern Laos. The efficacy of different remote sensing (RS) data sources in distinguishing forest patches that had different seizes, configurations, and vegetation structure was examined. These data were found to be sensitive to the varying levels of degradation of the different patch categories. Additionally, the role of local scale forest structure variables (characterized using the different RS data and patch area) and landscape variables (characterized by distance from different forest patches) in influencing habitat preferences of International Union for Conservation of Nature (IUCN) Red listed birds found in the study area was examined. A machine learning algorithm, MaxEnt, was used in conjunction with these data and field collected geographical locations of the avian species to identify the factors influencing habitat preference of the different bird species and their suitable habitats. Results show that distance from different forest patches played a more important role in influencing habitat suitability for the different avian species than local scale factors related to vegetation structure and health. In addition to distance from forest patches, LiDAR-derived forest structure and Landsat-derived spectral variables were important determinants of avian habitat preference. The models derived using MaxEnt were used to create an overall habitat suitability map (HSM) which mapped the most suitable habitat patches for sustaining all the

Modeling Impacts of Climate Change on Giant Panda Habitat

Directory of Open Access Journals (Sweden)

Melissa Songer

2012-01-01

Full Text Available Giant pandas (Ailuropoda melanoleuca are one of the most widely recognized endangered species globally. Habitat loss and fragmentation are the main threats, and climate change could significantly impact giant panda survival. We integrated giant panda habitat information with general climate models (GCMs to predict future geographic distribution and fragmentation of giant panda habitat. Results support a major general prediction of climate change—a shift of habitats towards higher elevation and higher latitudes. Our models predict climate change could reduce giant panda habitat by nearly 60% over 70 years. New areas may become suitable outside the current geographic range but much of these areas is far from the current giant panda range and only 15% fall within the current protected area system. Long-term survival of giant pandas will require the creation of new protected areas that are likely to support suitable habitat even if the climate changes.

The Invasive Species Forecasting System (ISFS): An iRODS-Based, Cloud-Enabled Decision Support System for Invasive Species Habitat Suitability Modeling

Science.gov (United States)

Gill, Roger; Schnase, John L.

2012-01-01

The Invasive Species Forecasting System (ISFS) is an online decision support system that allows users to load point occurrence field sample data for a plant species of interest and quickly generate habitat suitability maps for geographic regions of interest, such as a national park, monument, forest, or refuge. Target customers for ISFS are natural resource managers and decision makers who have a need for scientifically valid, model- based predictions of the habitat suitability of plant species of management concern. In a joint project involving NASA and the Maryland Department of Natural Resources, ISFS has been used to model the potential distribution of Wavyleaf Basketgrass in Maryland's Chesapeake Bay Watershed. Maximum entropy techniques are used to generate predictive maps using predictor datasets derived from remotely sensed data and climate simulation outputs. The workflow to run a model is implemented in an iRODS microservice using a custom ISFS file driver that clips and re-projects data to geographic regions of interest, then shells out to perform MaxEnt processing on the input data. When the model completes, all output files and maps from the model run are registered in iRODS and made accessible to the user. The ISFS user interface is a web browser that uses the iRODS PHP client to interact with the ISFS/iRODS- server. ISFS is designed to reside in a VMware virtual machine running SLES 11 and iRODS 3.0. The ISFS virtual machine is hosted in a VMware vSphere private cloud infrastructure to deliver the online service.

A multi-scale qualitative approach to assess the impact of urbanization on natural habitats and their connectivity

Energy Technology Data Exchange (ETDEWEB)

Scolozzi, Rocco, E-mail: rocco.scolozzi@fmach.it [Sustainable Agro-ecosystems and Bioresources Department, IASMA Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach 1, 38010 San Michele all& #x27; Adige, (Italy); Geneletti, Davide, E-mail: geneletti@ing.unitn.it [Department of Civil and Environmental Engineering, University of Trento, Trento (Italy)

2012-09-15

Habitat loss and fragmentation are often concurrent to land conversion and urbanization. Simple application of GIS-based landscape pattern indicators may be not sufficient to support meaningful biodiversity impact assessment. A review of the literature reveals that habitat definition and habitat fragmentation are frequently inadequately considered in environmental assessment, notwithstanding the increasing number of tools and approaches reported in the landscape ecology literature. This paper presents an approach for assessing impacts on habitats on a local scale, where availability of species data is often limited, developed for an alpine valley in northern Italy. The perspective of the methodology is multiple scale and species-oriented, and provides both qualitative and quantitative definitions of impact significance. A qualitative decision model is used to assess ecological values in order to support land-use decisions at the local level. Building on recent studies in the same region, the methodology integrates various approaches, such as landscape graphs, object-oriented rule-based habitat assessment and expert knowledge. The results provide insights into future habitat loss and fragmentation caused by land-use changes, and aim at supporting decision-making in planning and suggesting possible ecological compensation. - Highlights: Black-Right-Pointing-Pointer Many environmental assessments inadequately consider habitat loss and fragmentation. Black-Right-Pointing-Pointer Species-perspective for defining habitat quality and connectivity is claimed. Black-Right-Pointing-Pointer Species-based tools are difficult to be applied with limited availability of data. Black-Right-Pointing-Pointer We propose a species-oriented and multiple scale-based qualitative approach. Black-Right-Pointing-Pointer Advantages include being species-oriented and providing value-based information.

A multi-scale qualitative approach to assess the impact of urbanization on natural habitats and their connectivity

International Nuclear Information System (INIS)

Scolozzi, Rocco; Geneletti, Davide

2012-01-01

Habitat loss and fragmentation are often concurrent to land conversion and urbanization. Simple application of GIS-based landscape pattern indicators may be not sufficient to support meaningful biodiversity impact assessment. A review of the literature reveals that habitat definition and habitat fragmentation are frequently inadequately considered in environmental assessment, notwithstanding the increasing number of tools and approaches reported in the landscape ecology literature. This paper presents an approach for assessing impacts on habitats on a local scale, where availability of species data is often limited, developed for an alpine valley in northern Italy. The perspective of the methodology is multiple scale and species-oriented, and provides both qualitative and quantitative definitions of impact significance. A qualitative decision model is used to assess ecological values in order to support land-use decisions at the local level. Building on recent studies in the same region, the methodology integrates various approaches, such as landscape graphs, object-oriented rule-based habitat assessment and expert knowledge. The results provide insights into future habitat loss and fragmentation caused by land-use changes, and aim at supporting decision-making in planning and suggesting possible ecological compensation. - Highlights: ► Many environmental assessments inadequately consider habitat loss and fragmentation. ► Species-perspective for defining habitat quality and connectivity is claimed. ► Species-based tools are difficult to be applied with limited availability of data. ► We propose a species-oriented and multiple scale-based qualitative approach. ► Advantages include being species-oriented and providing value-based information.

BIOLOGI POPULASI RAJUNGAN (PORTUNUS PELAGICUS DAN KARAKTERISTIK LINGKUNGAN HABITAT ESENSIALNYA SEBAGAI UPAYA AWAL PERLINDUNGAN DI LAMPUNG TIMUR

Directory of Open Access Journals (Sweden)

Rahmat Kurnia

2014-04-01

Full Text Available There are several option management measures in preventing sustainability stock of the blue swimming crab (Portunus pelagicus, i.e., nursery ground conservation. Thus, the objective of this study was to analyses habitat characteristic and its population biology in the PGN marine embayment of Labuhan Maringgai, as one among crab habitat essential in East Lampung coastal water. The potential nursery ground conservation was assessed by habitat suitability index, carrying capacity, distribution and abundance as well as crabs size. The result shows that environmental condition was still suitable, even though the habitat carrying capacity tend to degraded by an increasing of turbidity and sedimentation at the embayment mouth. The crabs captured were also not representing of peak abundance season and recruitment during sampling period, while those crab size almost 100% under Lm50. The strategic management directive is required to control in utilization of crab’s essential habitat, including crab fishing by any fishing gear resulted undersize captured crabs. Meanwhile, to propose habitat essential conservation might need more consideration and comprehensive study, including social economic and cultural aspects and co-management approach may be required in management measure applied.

Suitability

NARCIS (Netherlands)

Bokdam, J.; Braeckel, van A.

2002-01-01

The suitability of grazing, burning, mowing and cutting as tools for succession control in peatland was assessed and expressed on a scale from 0 - 1. All management tools are suitable, but their effects are conditional. The suitability depends on the targeted vegetation transition and on their

Where to Combat Shrub Encroachment in Alpine Timberline Ecosystems: Combining Remotely-Sensed Vegetation Information with Species Habitat Modelling.

Directory of Open Access Journals (Sweden)

Veronika Braunisch

Full Text Available In many cultural landscapes, the abandonment of traditional grazing leads to encroachment of pastures by woody plants, which reduces habitat heterogeneity and impacts biodiversity typical of semi-open habitats. We developed a framework of mutually interacting spatial models to locate areas where shrub encroachment in Alpine treeline ecosystems deteriorates vulnerable species' habitat, using black grouse Tetrao tetrix (L. in the Swiss Alps as a study model. Combining field observations and remote-sensing information we 1 identified and located the six predominant treeline vegetation types; 2 modelled current black grouse breeding habitat as a function thereof so as to derive optimal habitat profiles; 3 simulated from these profiles the theoretical spatial extension of breeding habitat when assuming optimal vegetation conditions throughout; and used the discrepancy between (2 and (3 to 4 locate major aggregations of homogeneous shrub vegetation in otherwise suitable breeding habitat as priority sites for habitat restoration. All six vegetation types (alpine pasture, coniferous forest, Alnus viridis (Chaix, Rhododendron-dominated, Juniperus-dominated and mixed heathland were predicted with high accuracy (AUC >0.9. Breeding black grouse preferred a heterogeneous mosaic of vegetation types, with none exceeding 50% cover. While 15% of the timberline belt currently offered suitable breeding habitat, twice that fraction (29% would potentially be suitable when assuming optimal shrub and ground vegetation conditions throughout the study area. Yet, only 10% of this difference was attributed to habitat deterioration by shrub-encroachment of dense heathland (all types 5.2% and Alnus viridis (4.8%. The presented method provides both a general, large-scale assessment of areas covered by dense shrub vegetation as well as specific target values and priority areas for habitat restoration related to a selected target organism. This facilitates optimizing the

Where to Combat Shrub Encroachment in Alpine Timberline Ecosystems: Combining Remotely-Sensed Vegetation Information with Species Habitat Modelling.

Science.gov (United States)

Braunisch, Veronika; Patthey, Patrick; Arlettaz, Raphaël

2016-01-01

In many cultural landscapes, the abandonment of traditional grazing leads to encroachment of pastures by woody plants, which reduces habitat heterogeneity and impacts biodiversity typical of semi-open habitats. We developed a framework of mutually interacting spatial models to locate areas where shrub encroachment in Alpine treeline ecosystems deteriorates vulnerable species' habitat, using black grouse Tetrao tetrix (L.) in the Swiss Alps as a study model. Combining field observations and remote-sensing information we 1) identified and located the six predominant treeline vegetation types; 2) modelled current black grouse breeding habitat as a function thereof so as to derive optimal habitat profiles; 3) simulated from these profiles the theoretical spatial extension of breeding habitat when assuming optimal vegetation conditions throughout; and used the discrepancy between (2) and (3) to 4) locate major aggregations of homogeneous shrub vegetation in otherwise suitable breeding habitat as priority sites for habitat restoration. All six vegetation types (alpine pasture, coniferous forest, Alnus viridis (Chaix), Rhododendron-dominated, Juniperus-dominated and mixed heathland) were predicted with high accuracy (AUC >0.9). Breeding black grouse preferred a heterogeneous mosaic of vegetation types, with none exceeding 50% cover. While 15% of the timberline belt currently offered suitable breeding habitat, twice that fraction (29%) would potentially be suitable when assuming optimal shrub and ground vegetation conditions throughout the study area. Yet, only 10% of this difference was attributed to habitat deterioration by shrub-encroachment of dense heathland (all types 5.2%) and Alnus viridis (4.8%). The presented method provides both a general, large-scale assessment of areas covered by dense shrub vegetation as well as specific target values and priority areas for habitat restoration related to a selected target organism. This facilitates optimizing the spatial

Assessment in Action : Assessing and Displaying Suitability for Adoptive Parenthood through Text and Talk

NARCIS (Netherlands)

Noordegraaf, M.

2008-01-01

'Assessment in action' is an ethnographical conversation analysis of how suitability for adoptive parenthood is assessed in institutional interaction. It is about talking with clients and transforming this talk into documents. Conversations and texts are submitted to a sentence by sentence analysis

78 FR 5830 - Draft Environmental Assessment and Proposed Habitat Conservation Plan for the Interim Operations...

Science.gov (United States)

2013-01-28

...-FXES11120800000F2-123-F2] Draft Environmental Assessment and Proposed Habitat Conservation Plan for the Interim Operations of PacifiCorp's Klamath Hydroelectric Project on the Klamath River, Klamath County, OR, and... environmental assessment and proposed habitat conservation plan; request for comment. SUMMARY: We, the U.S. Fish...

Habitat Evaluation Procedures (HEP) Report; Gamblin Lake, Technical Report 2005.

Energy Technology Data Exchange (ETDEWEB)

Entz, Ray

2005-05-01

On August 12, 2003, the Habitat Evaluation Procedure (HEP) was used to determine baseline habitat suitability on the Gamblin Lake property, an acquisition completed by the Kalispel Tribe of Indians in December 2002. Evaluation species and appropriate models include bald eagle, black-capped chickadee, mallard, muskrat, and white-tailed deer. Habitat Suitability Index (HSI) values were visually estimated and agreed upon by all HEP team members. The Gamblin Lake Project provides a total of 273.28 Habitat Units (HUs) for the species evaluated. Conifer forest habitat provides 127.92 HUs for bald eagle, black-capped chickadee, mallard, and white-tailed deer. Forested wetland habitat provides 21.06 HUs for bald eagle, black-caped chickadee, mallard, and white-tailed deer. Wet meadow provides 78.05 HUs for Canada goose and mallard. Emergent wetland habitat provides 46.25 HUs for mallard, muskrat, and Canada goose. The objective of using HEP at the Gamblin Lake Project and other protected properties is to document the quality and quantity of available habitat for selected wildlife species. In this way, HEP provides information on the relative value of the same area at future points in time so that the effect of management activities on wildlife habitat can be quantified. When combined with other tools, the baseline HEP will be used to determine the most effective on-site management, restoration, and enhancement actions to increase habitat suitability for targeted species. The same process will be replicated every five years to quantitatively evaluate the effectiveness of management strategies in improving and maintaining habitat conditions while providing additional crediting to BPA for enhanced habitat values.

Habitat type-based bioaccumulation and risk assessment of metal and As contamination in earthworms, beetles and woodlice

International Nuclear Information System (INIS)

Vermeulen, Frouke; Van den Brink, Nico W.; D'Have, Helga; Mubiana, Valentine K.; Blust, Ronny; Bervoets, Lieven; De Coen, Wim

2009-01-01

The present study investigated the contribution of environmental factors to the accumulation of As, Cd, Cu, Pb and Zn in earthworms, beetles and woodlice, and framed within an exposure assessment of the European hedgehog. Soil and invertebrate samples were collected in three distinct habitat types. Results showed habitat-specific differences in soil and invertebrate metal concentrations and bioaccumulation factors when normalized to soil metal concentration. Further multiple regression analysis showed residual variability (habitat differences) in bioaccumulation that could not be fully explained by differences in soil metal contamination, pH or organic carbon (OC). Therefore, the study demonstrated that in bioaccumulation studies involving terrestrial invertebrates or in risk assessment of metals, it is not sufficient to differentiate habitat types on general soil characteristics such as pH and/or OC alone. Furthermore, simple generic soil risk assessments for Cd and Cu showed that risk characterization was more accurate when performed in a habitat-specific way. - Our study provided essential insights into habitat-specific accumulation patterns with respect to factors influencing metal bioaccumulation, BAFs, and site-specific risk assessment.

Habitat type-based bioaccumulation and risk assessment of metal and As contamination in earthworms, beetles and woodlice

Energy Technology Data Exchange (ETDEWEB)

Vermeulen, Frouke, E-mail: frouke.vermeulen@ua.ac.b [Ecophysiology, Biochemistry and Toxicology Group (U7), University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Van den Brink, Nico W., E-mail: nico.vandenbrink@wur.n [Alterra, Wageningen UR, Box 47, NL6700AA Wageningen (Netherlands); D' Have, Helga [Ecophysiology, Biochemistry and Toxicology Group (U7), University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Mubiana, Valentine K., E-mail: kayawe.mubiana@ua.ac.b [Ecophysiology, Biochemistry and Toxicology Group (U7), University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Blust, Ronny, E-mail: ronny.blust@ua.ac.b [Ecophysiology, Biochemistry and Toxicology Group (U7), University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Bervoets, Lieven, E-mail: lieven.bervoets@ua.ac.b [Ecophysiology, Biochemistry and Toxicology Group (U7), University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); De Coen, Wim, E-mail: wim.decoen@ua.ac.b [Ecophysiology, Biochemistry and Toxicology Group (U7), University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium)

2009-11-15

The present study investigated the contribution of environmental factors to the accumulation of As, Cd, Cu, Pb and Zn in earthworms, beetles and woodlice, and framed within an exposure assessment of the European hedgehog. Soil and invertebrate samples were collected in three distinct habitat types. Results showed habitat-specific differences in soil and invertebrate metal concentrations and bioaccumulation factors when normalized to soil metal concentration. Further multiple regression analysis showed residual variability (habitat differences) in bioaccumulation that could not be fully explained by differences in soil metal contamination, pH or organic carbon (OC). Therefore, the study demonstrated that in bioaccumulation studies involving terrestrial invertebrates or in risk assessment of metals, it is not sufficient to differentiate habitat types on general soil characteristics such as pH and/or OC alone. Furthermore, simple generic soil risk assessments for Cd and Cu showed that risk characterization was more accurate when performed in a habitat-specific way. - Our study provided essential insights into habitat-specific accumulation patterns with respect to factors influencing metal bioaccumulation, BAFs, and site-specific risk assessment.

Land Suitability Assessment for Sugarcane in "Herois de Caxito" (Angola

Directory of Open Access Journals (Sweden)

Baert, G.

2005-01-01

Full Text Available The suitability of the soils surrounding the sugarcane plantation at "Herois de Caxito" (7068 ha is assessed. The main goal is to identify land suitability for the enlargement of the present plantation, using FAO land evaluation models (modified to suit Herois de Caxito conditions and GIS. Calculations of the radiationthermal production potential (RPP, land production potential (LPP, irrigation suitability index, and evaluation of the irrigation water quality are done. The water-limited production potential (WPP is found equal to the RPP, because water needs were fully met under irrigation. Maps showing the spatial distribution of the LPP and the suitability for irrigation are generated. The matching of irrigation and fertility indices has shown that, about 40% of the soils with good fertility for sugarcane production present low suitability for irrigation, the main limitations being the very fine texture and the drainage. The available surface water at Herois de Caxito (Dande river is of very good quality for irrigation of sugarcane.

Assessing vulnerability of giant pandas to climate change in the Qinling Mountains of China.

Science.gov (United States)

Li, Jia; Liu, Fang; Xue, Yadong; Zhang, Yu; Li, Diqiang

2017-06-01

Climate change might pose an additional threat to the already vulnerable giant panda ( Ailuropoda melanoleuca ). Effective conservation efforts require projections of vulnerability of the giant panda in facing climate change and proactive strategies to reduce emerging climate-related threats. We used the maximum entropy model to assess the vulnerability of giant panda to climate change in the Qinling Mountains of China. The results of modeling included the following findings: (1) the area of suitable habitat for giant pandas was projected to decrease by 281 km 2 from climate change by the 2050s; (2) the mean elevation of suitable habitat of giant panda was predicted to shift 30 m higher due to climate change over this period; (3) the network of nature reserves protect 61.73% of current suitable habitat for the species, and 59.23% of future suitable habitat; (4) current suitable habitat mainly located in Chenggu, Taibai, and Yangxian counties (with a total area of 987 km 2 ) was predicted to be vulnerable. Assessing the vulnerability of giant panda provided adaptive strategies for conservation programs and national park construction. We proposed adaptation strategies to ameliorate the predicted impacts of climate change on giant panda, including establishing and adjusting reserves, establishing habitat corridors, improving adaptive capacity to climate change, and strengthening monitoring of giant panda.

Assessing species habitat using Google Street View: a case study of cliff-nesting vultures.

Science.gov (United States)

Olea, Pedro P; Mateo-Tomás, Patricia

2013-01-01

The assessment of a species' habitat is a crucial issue in ecology and conservation. While the collection of habitat data has been boosted by the availability of remote sensing technologies, certain habitat types have yet to be collected through costly, on-ground surveys, limiting study over large areas. Cliffs are ecosystems that provide habitat for a rich biodiversity, especially raptors. Because of their principally vertical structure, however, cliffs are not easy to study by remote sensing technologies, posing a challenge for many researches and managers working with cliff-related biodiversity. We explore the feasibility of Google Street View, a freely available on-line tool, to remotely identify and assess the nesting habitat of two cliff-nesting vultures (the griffon vulture and the globally endangered Egyptian vulture) in northwestern Spain. Two main usefulness of Google Street View to ecologists and conservation biologists were evaluated: i) remotely identifying a species' potential habitat and ii) extracting fine-scale habitat information. Google Street View imagery covered 49% (1,907 km) of the roads of our study area (7,000 km²). The potential visibility covered by on-ground surveys was significantly greater (mean: 97.4%) than that of Google Street View (48.1%). However, incorporating Google Street View to the vulture's habitat survey would save, on average, 36% in time and 49.5% in funds with respect to the on-ground survey only. The ability of Google Street View to identify cliffs (overall accuracy = 100%) outperformed the classification maps derived from digital elevation models (DEMs) (62-95%). Nonetheless, high-performance DEM maps may be useful to compensate Google Street View coverage limitations. Through Google Street View we could examine 66% of the vultures' nesting-cliffs existing in the study area (n = 148): 64% from griffon vultures and 65% from Egyptian vultures. It also allowed us the extraction of fine-scale features of cliffs

Modeling and Validation of Environmental Suitability for Schistosomiasis Transmission Using Remote Sensing.

Science.gov (United States)

Walz, Yvonne; Wegmann, Martin; Dech, Stefan; Vounatsou, Penelope; Poda, Jean-Noël; N'Goran, Eliézer K; Utzinger, Jürg; Raso, Giovanna

2015-11-01

Schistosomiasis is the most widespread water-based disease in sub-Saharan Africa. Transmission is governed by the spatial distribution of specific freshwater snails that act as intermediate hosts and human water contact patterns. Remote sensing data have been utilized for spatially explicit risk profiling of schistosomiasis. We investigated the potential of remote sensing to characterize habitat conditions of parasite and intermediate host snails and discuss the relevance for public health. We employed high-resolution remote sensing data, environmental field measurements, and ecological data to model environmental suitability for schistosomiasis-related parasite and snail species. The model was developed for Burkina Faso using a habitat suitability index (HSI). The plausibility of remote sensing habitat variables was validated using field measurements. The established model was transferred to different ecological settings in Côte d'Ivoire and validated against readily available survey data from school-aged children. Environmental suitability for schistosomiasis transmission was spatially delineated and quantified by seven habitat variables derived from remote sensing data. The strengths and weaknesses highlighted by the plausibility analysis showed that temporal dynamic water and vegetation measures were particularly useful to model parasite and snail habitat suitability, whereas the measurement of water surface temperature and topographic variables did not perform appropriately. The transferability of the model showed significant relations between the HSI and infection prevalence in study sites of Côte d'Ivoire. A predictive map of environmental suitability for schistosomiasis transmission can support measures to gain and sustain control. This is particularly relevant as emphasis is shifting from morbidity control to interrupting transmission. Further validation of our mechanistic model needs to be complemented by field data of parasite- and snail

Habitat Evaluation Procedures (HEP) Report : Priest River, 2004-2005 Technical Report.

Energy Technology Data Exchange (ETDEWEB)

Entz, Ray

2005-02-01

On July 6, 2004, the Habitat Evaluation Procedure (HEP) was used to determine baseline habitat suitability on the Priest River property, an acquisition completed by the Kalispel Tribe of Indians in 2001. Evaluation species and appropriate models include bald eagle, black-capped chickadee, Canada goose, mallard, yellow warbler, and white-tailed deer. Habitat Suitability Index (HSI) values were visually estimated and agreed upon by all HEP team members. The Priest River Project provides a total of 105.41 Habitat Units (HUs) for the species evaluated. Conifer forest habitat provides 26.95 HUs for bald eagle, black-capped chickadee, and white-tailed deer. Grassland habitat provides 23.78 HUs for Canada goose and mallard. Scmb-shrub vegetation provides 54.68 HUs for mallard, yellow warbler, and white-tailed deer.

Habitat Evaluation Procedures (HEP) Report; Beaver Lake, Technical Report 2005.

Energy Technology Data Exchange (ETDEWEB)

Entz, Ray

2005-05-01

On August 14, 2003, the Habitat Evaluation Procedure (HEP) was used to determine baseline habitat suitability on the Beaver Lake property, an acquisition completed by the Kalispel Tribe of Indians in November 2002. Evaluation species and appropriate models include bald eagle, black-capped chickadee, Canada goose, mallard, muskrat, yellow warbler, and white-tailed deer. Habitat Suitability Index (HSI) values were visually estimated and agreed upon by all HEP team members. The Beaver Lake Project provides a total of 232.26 Habitat Units (HUs) for the species evaluated. Conifer forest habitat provides 136.58 HUs for bald eagle, black-capped chickadee, mallard, and white-tailed deer. Forested wetland habitat provides 20.02 HUs for bald eagle, black-caped chickadee, mallard, and white-tailed deer. Scrub-shrub wetland habitat provides 7.67 HUs for mallard, yellow warbler, and white-tailed deer. Grassland meadow provides 22.69 HUs for Canada goose and mallard. Emergent wetlands provide 35.04 HUs for Canada goose, mallard, and muskrat. Open water provided 10.26 HUs for Canada goose, mallard, and muskrat. The objective of using HEP at the Beaver Lake Project and other protected properties is to document the quality and quantity of available habitat for selected wildlife species. In this way, HEP provides information on the relative value of the same area at future points in time so that the effect of management activities on wildlife habitat can be quantified. When combined with other tools, the baseline HEP will be used to determine the most effective on-site management, restoration, and enhancement actions to increase habitat suitability for targeted species. The same process will be replicated every five years to quantitatively evaluate the effectiveness of management strategies in improving and maintaining habitat conditions while providing additional crediting to BPA for enhanced habitat values.

[Cultural regionalization for Notopterygium incisum based on 3S technology platform. I. Evaluation for growth suitability for N. incisum based on ecological factors analysis by Maxent and ArcGIS model].

Science.gov (United States)

Sun, Hong-bing; Sun, Hui; Jiang, Shun-yuan; Zhou, Yi; Cao, Wen-long; Ji, Ming-chang; Zhy, Wen-tao; Yan, Han-jing

2015-03-01

Growth suitability as assessment indicators for medicinal plants cultivation was proposed based on chemical quality determination and ecological factors analysis by Maxent and ArcGIS model. Notopterygium incisum, an endangered Chinese medicinal plant, was analyzed as a case, its potential distribution areas at different suitability grade and regionalization map were formulated based on growth suitability theory. The results showed that the most suitable habitats is Sichuan province, and more than 60% of the most suitable areawas located in the western Sichuan such as Aba and Ganzi prefectures for N. incisum. The results indicated that habitat altitude, average air temperature in September, and vegetation types were the dominant factors contributing to the grade of plant growth, precipitation and slope were the major factors contributing to notopterol accumulation in its underground parts, while isoimperatorin in its underground parts was negatively corelated with precipitation and slope of its habitat. However, slope as a factor influencing chemical components seemed to be a pseudo corelationship. Therefore, there were distinguishing differences between growth suitability and quality suitability for medicinal plants, which was helpful to further research and practice of cultivation regionalization, wild resource monitoring and large-scale cultivation of traditional Chinese medicine plants.

Prioritizing tropical habitats for long-distance migratory songbirds: an assessment of habitat quality at a stopover site in Colombia

Directory of Open Access Journals (Sweden)

Nicholas J. Bayly

2016-12-01

Full Text Available Long-distance migratory birds are declining globally and migration has been identified as the primary source of mortality in this group. Despite this, our lack of knowledge of habitat use and quality at stopovers, i.e., sites where the energy for migration is accumulated, remains a barrier to designing appropriate conservation measures, especially in tropical regions. There is therefore an urgent need to assess stopover habitat quality and concurrently identify efficient and cost-effective methods for doing so. Given that fuel deposition rates directly influence stopover duration, departure fuel load, and subsequent speed of migration, they are expected to provide a direct measure of habitat quality and have the advantage of being measurable through body-mass changes. Here, we examined seven potential indicators of quality, including body-mass change, for two ecologically distinct Neotropical migratory landbirds on stopover in shade-coffee plantations and tropical humid premontane forest during spring migration in Colombia: (1 rate of body-mass change; (2 foraging rate; (3 recapture rate; (4 density; (5 flock size; (6 age and sex ratios; and (7 body-mass distribution. We found higher rates of mass change in premontane forest than in shade-coffee in Tennessee Warbler Oreothlypis peregrina, a difference that was mirrored in higher densities and body masses in forest. In Gray-cheeked Thrush Catharus minimus, a lack of recaptures in shade-coffee and higher densities in forest, also suggested that forest provided superior fueling conditions. For a reliable assessment of habitat quality, we therefore recommend using a suite of indicators, taking into account each species' ecology and methodological considerations. Our results also imply that birds stopping over in lower quality habitats may spend a longer time migrating and require more stopovers, potentially leading to important carryover effects on reproductive fitness. Evaluating habitat quality is

Crucial nesting habitat for gunnison sage-grouse: A spatially explicit hierarchical approach

Science.gov (United States)

Aldridge, Cameron L.; Saher, D.J.; Childers, T.M.; Stahlnecker, K.E.; Bowen, Z.H.

2012-01-01

Gunnison sage-grouse (Centrocercus minimus) is a species of special concern and is currently considered a candidate species under Endangered Species Act. Careful management is therefore required to ensure that suitable habitat is maintained, particularly because much of the species' current distribution is faced with exurban development pressures. We assessed hierarchical nest site selection patterns of Gunnison sage-grouse inhabiting the western portion of the Gunnison Basin, Colorado, USA, at multiple spatial scales, using logistic regression-based resource selection functions. Models were selected using Akaike Information Criterion corrected for small sample sizes (AIC c) and predictive surfaces were generated using model averaged relative probabilities. Landscape-scale factors that had the most influence on nest site selection included the proportion of sagebrush cover >5%, mean productivity, and density of 2 wheel-drive roads. The landscape-scale predictive surface captured 97% of known Gunnison sage-grouse nests within the top 5 of 10 prediction bins, implicating 57% of the basin as crucial nesting habitat. Crucial habitat identified by the landscape model was used to define the extent for patch-scale modeling efforts. Patch-scale variables that had the greatest influence on nest site selection were the proportion of big sagebrush cover >10%, distance to residential development, distance to high volume paved roads, and mean productivity. This model accurately predicted independent nest locations. The unique hierarchical structure of our models more accurately captures the nested nature of habitat selection, and allowed for increased discrimination within larger landscapes of suitable habitat. We extrapolated the landscape-scale model to the entire Gunnison Basin because of conservation concerns for this species. We believe this predictive surface is a valuable tool which can be incorporated into land use and conservation planning as well the assessment of

Habitat Evaluation Procedures (HEP) Report : West Beaver Lake, 2004-2005 Technical Report.

Energy Technology Data Exchange (ETDEWEB)

Entz, Ray

2005-02-01

On September 7, 2004, the Habitat Evaluation Procedure (HEP) was used to determine baseline habitat suitability on the West Beaver Lake property, an acquisition completed by the Kalispel Tribe of Indians in September 2004. Evaluation species and appropriate models include bald eagle, black-capped chickadee, mallard, muskrat, and white-tailed deer. Habitat Suitability Index (HSI) values were visually estimated and agreed upon by all HEP team members. The West Beaver Lake Project provides a total of 103.08 Habitat Units (HUs) for the species evaluated. Emergent wetland habitat provides 7.17 HUs for mallard and muskrat. Conifer forest habitat provides 95.91 HUs for bald eagle, black-capped chickadee, mallard, and white-tailed deer. The objective of using HEP at the West Beaver Lake Project and other protected properties is to document the quality and quantity of available habitat for selected wildlife species. In this way, HEP provides information on the relative value of the same area at future points in time so that the effect of management activities on wildlife habitat can be quantified. When combined with other tools, the baseline HEP will be used to determine the most effective on-site management, restoration, and enhancement actions to increase habitat suitability for targeted species. The same process will be replicated every five years to quantitatively evaluate the effectiveness of management strategies in improving and maintaining habitat conditions while providing additional crediting to BPA for enhanced habitat values.

Habitat Evaluation Procedures (HEP) Report; Priest River Project, Technical Report 2005.

Energy Technology Data Exchange (ETDEWEB)

Entz, Ray

2005-05-01

On July 6, 2004, the Habitat Evaluation Procedure (HEP) was used to determine baseline habitat suitability on the Priest River property, an acquisition completed by the Kalispel Tribe of Indians in 2001. Evaluation species and appropriate models include bald eagle, black-capped chickadee, Canada goose, mallard, yellow warbler, and white-tailed deer. Habitat Suitability Index (HSI) values were visually estimated and agreed upon by all HEP team members. The Priest River Project provides a total of 140.73 Habitat Units (HUs) for the species evaluated. Conifer forest habitat provides 60.05 HUs for bald eagle, black-capped chickadee, and white-tailed deer. Grassland meadow habitat provides 7.39 HUs for Canada goose and mallard. Scrub-shrub vegetation provides 71.13 HUs for mallard, yellow warbler, and white-tailed deer. Open water habitat provides 2.16 HUs for Canada goose and mallard. The objective of using HEP at the Priest River Project and other protected properties is to document the quality and quantity of available habitat for selected wildlife species. In this way, HEP provides information on the relative value of the same area at future points in time so that the effect of management activities on wildlife habitat can be quantified. When combined with other tools, the baseline HEP will be used to determine the most effective on-site management, restoration, and enhancement actions to increase habitat suitability for targeted species. The same process will be replicated every five years to quantitatively evaluate the effectiveness of management strategies in improving and maintaining habitat conditions while providing additional crediting to BPA for enhanced habitat values.

Habitat Evaluation Procedures (HEP) Report; North Eaton Lake, Technical Report 2005.

Energy Technology Data Exchange (ETDEWEB)

Entz, Ray

2005-11-01

On July 6, 2005, the Habitat Evaluation Procedure (HEP) was used to determine baseline habitat suitability on the North Eaton Lake property, an acquisition completed by the Kalispel Tribe of Indians in November 2004. Evaluation species and appropriate models include bald eagle, black-capped chickadee, Canada goose, mallard, muskrat, and white-tailed deer. Habitat Suitability Index (HSI) values were visually estimated and agreed upon by all HEP team members. The North Eaton Lake Project provides a total of 235.05 Habitat Units (HUs) for the species evaluated. Open water habitat provides 9.38 HUs for Canada goose, mallard and muskrat. Emergent wetland habitat provides 11.36 HUs for Canada goose, mallard and muskrat. Forested wetland provides 10.97 HUs for bald eagle, black-capped chickadee, mallard and white-tailed deer. Conifer forest habitat provides 203.34 HUs for bald eagle, black-capped chickadee, mallard, and white-tailed deer. The objective of using HEP at the North Eaton Lake Project and other protected properties is to document the quality and quantity of available habitat for selected wildlife species. In this way, HEP provides information on the relative value of the same area at future points in time so that the effect of management activities on wildlife habitat can be quantified. When combined with other tools, the baseline HEP will be used to determine the most effective on-site management, restoration, and enhancement actions to increase habitat suitability for targeted species. The same process will be replicated every five years to quantitatively evaluate the effectiveness of management strategies in improving and maintaining habitat conditions while providing additional crediting to BPA for enhanced habitat values.

The energetic consequences of habitat structure for forest stream salmonids.

Science.gov (United States)

Naman, Sean M; Rosenfeld, Jordan S; Kiffney, Peter M; Richardson, John S

2018-05-08

1.Increasing habitat availability (i.e. habitat suitable for occupancy) is often assumed to elevate the abundance or production of mobile consumers; however, this relationship is often nonlinear (threshold or unimodal). Identifying the mechanisms underlying these nonlinearities is essential for predicting the ecological impacts of habitat change, yet the functional forms and ultimate causation of consumer-habitat relationships are often poorly understood. 2.Nonlinear effects of habitat on animal abundance may manifest through physical constraints on foraging that restrict consumers from accessing their resources. Subsequent spatial incongruence between consumers and resources should lead to unimodal or saturating effects of habitat availability on consumer production if increasing the area of habitat suitable for consumer occupancy comes at the expense of habitats that generate resources. However, the shape of this relationship could be sensitive to cross-ecosystem prey subsidies, which may be unrelated to recipient habitat structure and result in more linear habitat effects on consumer production. 3.We investigated habitat-productivity relationships for juveniles of stream-rearing Pacific salmon and trout (Oncorhynchus spp.), which typically forage in low-velocity pool habitats, while their prey (drifting benthic invertebrates) are produced upstream in high-velocity riffles. However, juvenile salmonids also consume subsidies of terrestrial invertebrates that may be independent of pool-riffle structure. 4.We measured salmonid biomass production in 13 experimental enclosures each containing a downstream pool and upstream riffle, spanning a gradient of relative pool area (14-80% pool). Increasing pool relative to riffle habitat area decreased prey abundance, leading to a nonlinear saturating effect on fish production. We then used bioenergetics model simulations to examine how the relationship between pool area and salmonid biomass is affected by varying levels of

[Prediction of the suitable distribution and responses to climate change of Elaeagnus mollis in Shanxi Province, China].

Science.gov (United States)

Zhang, Yin Bo; Gao, Chen Hong; Qin, Hao

2018-04-01

Understanding the responses of the habitats of endangered species to climate change is of great significance for biodiversity conservation and the maintenance of the integrity of ecosystem function. In this study, the potential suitable distribution habitats of Elaeagnus mollis in Shanxi Province was simulated by the maximum entropy model, based on 73 occurrence field records and 35 environmental factors under the current climate condition. Moreover, with the Fifth Assessment Report of Intergovernmental Panel on Climate Change, the dynamics of distribution pattern was analyzed for E. mollis under different climate scenarios. The results showed that the area under the receiver operating characteristic curve (AUC) value was 0.987, indicating that the data fitted the model very well and that the prediction was highly reliable. Results from the Jackknife test showed that the main environmental variables affecting the E. mollis distribution were the precipitation seasonality, the range of annual temperature, annual mean temperature, isothermality, annual precipitation, and pH of topsoil, with the cumulative contribution reaching 94.8%. At present, the potential suitable habitats of E. mollis are mainly located in two regions, the southern of Lyuliang Mountain and Zhongtiao Mountain in Shanxi Province. Under different climate scenarios, the total suitable area of E. mollis would shrink in 2070s. In RCP 2.6 the suitable area would firstly increase and then decrease, while in RCP 4.5 and RCP 8.5 it would response sensitively and first decrease and then increase. Its spatial distribution in two suitable regions would show divergent responses to climate change. The distribution in southern Lyuliang Mountain would fluctuate slightly in latitudinal direction, while that in Zhongtiao Mountain would migrate along elevation.

Assessment of Habitat Suitability Is Affected by Plant-Soil Feedback: Comparison of Field and Garden Experiment.

Directory of Open Access Journals (Sweden)

Lucie Hemrová

Full Text Available Field translocation experiments (i.e., the introduction of seeds or seedlings of different species into different localities are commonly used to study habitat associations of species, as well as factors limiting species distributions and local abundances. Species planted or sown in sites where they naturally occur are expected to perform better or equally well compared to sites at which they do not occur or are rare. This, however, contrasts with the predictions of the Janzen-Connell hypothesis and commonly reported intraspecific negative plant-soil feedback. The few previous studies indicating poorer performance of plants at sites where they naturally occur did not explore the mechanisms behind this pattern.In this study, we used field translocation experiments established using both seeds and seedlings to study the determinants of local abundance of four dominant species in grasslands. To explore the possible effects of intraspecific negative plant-soil feedback on our results, we tested the effect of local species abundance on the performance of the plants in the field experiment. In addition, we set up a garden experiment to explore the intensity of intraspecific as well as interspecific feedback between the dominants used in the experiment.In some cases, the distribution and local abundances of the species were partly driven by habitat conditions at the sites, and species performed better at their own sites. However, the prevailing pattern was that the local dominants performed worse at sites where they naturally occur than at any other sites. Moreover, the success of plants in the field experiment was lower in the case of higher intraspecific abundance prior to experimental setup. In the garden feedback experiment, two of the species performed significantly worse in soils conditioned by their species than in soils conditioned by the other species. In addition, the performance of the plants was significantly correlated between the two

Inter-annual variability of North Sea plaice spawning habitat

Science.gov (United States)

Loots, C.; Vaz, S.; Koubbi, P.; Planque, B.; Coppin, F.; Verin, Y.

2010-11-01

Potential spawning habitat is defined as the area where environmental conditions are suitable for spawning to occur. Spawning adult data from the first quarter (January-March) of the International Bottom Trawl Survey have been used to study the inter-annual variability of the potential spawning habitat of North Sea plaice from 1980 to 2007. Generalised additive models (GAM) were used to create a model that related five environmental variables (depth, bottom temperature and salinity, seabed stress and sediment type) to presence-absence and abundance of spawning adults. Then, the habitat model was applied each year from 1970 to 2007 to predict inter-annual variability of the potential spawning habitat. Predicted responses obtained by GAM for each year were mapped using kriging. A hierarchical classification associated with a correspondence analysis was performed to cluster spawning suitable areas and to determine how they evolved across years. The potential spawning habitat was consistent with historical spawning ground locations described in the literature from eggs surveys. It was also found that the potential spawning habitat varied across years. Suitable areas were located in the southern part of the North Sea and along the eastern coast of England and Scotland in the eighties; they expanded further north from the nineties. Annual survey distributions did not show such northward expansion and remained located in the southern North Sea. This suggests that this species' actual spatial distribution remains stable against changing environmental conditions, and that the potential spawning habitat is not fully occupied. Changes in environmental conditions appear to remain within plaice environmental ranges, meaning that other factors may control the spatial distribution of plaice spawning habitat.

Landsat ETM+ and SRTM Data Provide Near Real-Time Monitoring of Chimpanzee (Pan troglodytes Habitats in Africa

Directory of Open Access Journals (Sweden)

Samuel M. Jantz

2016-05-01

Full Text Available All four chimpanzee sub-species populations are declining due to multiple factors including human-caused habitat loss. Effective conservation efforts are therefore needed to ensure their long-term survival. Habitat suitability models serve as useful tools for conservation planning by depicting relative environmental suitability in geographic space over time. Previous studies mapping chimpanzee habitat suitability have been limited to small regions or coarse spatial and temporal resolutions. Here, we used Random Forests regression to downscale a coarse resolution habitat suitability calibration dataset to estimate habitat suitability over the entire chimpanzee range at 30-m resolution. Our model predicted habitat suitability well with an r2 of 0.82 (±0.002 based on 50-fold cross validation where 75% of the data was used for model calibration and 25% for model testing; however, there was considerable variation in the predictive capability among the four sub-species modeled individually. We tested the influence of several variables derived from Landsat Enhanced Thematic Mapper Plus (ETM+ that included metrics of forest canopy and structure for four three-year time periods between 2000 and 2012. Elevation, Landsat ETM+ band 5 and Landsat derived canopy cover were the strongest predictors; highly suitable areas were associated with dense tree canopy cover for all but the Nigeria-Cameroon and Central Chimpanzee sub-species. Because the models were sensitive to such temporally based predictors, our results are the first to highlight the value of integrating continuously updated variables derived from satellite remote sensing into temporally dynamic habitat suitability models to support  near real-time monitoring of habitat status and decision support systems.

Modeling intrinsic potential for beaver (Castor canadensis) habitat to inform restoration and climate change adaptation

Science.gov (United States)

Dittbrenner, Benjamin J.; Pollack, Michael M.; Schilling, Jason W.; Olden, Julian D.; Lawler, Joshua J.; Torgersen, Christian E.

2018-01-01

Through their dam-building activities and subsequent water storage, beaver have the potential to restore riparian ecosystems and offset some of the predicted effects of climate change by modulating streamflow. Thus, it is not surprising that reintroducing beaver to watersheds from which they have been extirpated is an often-used restoration and climate-adaptation strategy. Identifying sites for reintroduction, however, requires detailed information about habitat factors—information that is not often available at broad spatial scales. Here we explore the potential for beaver relocation throughout the Snohomish River Basin in Washington, USA with a model that identifies some of the basic building blocks of beaver habitat suitability and does so by relying solely on remotely sensed data. More specifically, we developed a generalized intrinsic potential model that draws on remotely sensed measures of stream gradient, stream width, and valley width to identify where beaver could become established if suitable vegetation were to be present. Thus, the model serves as a preliminary screening tool that can be applied over relatively large extents. We applied the model to 5,019 stream km and assessed the ability of the model to correctly predict beaver habitat by surveying for beavers in 352 stream reaches. To further assess the potential for relocation, we assessed land ownership, use, and land cover in the landscape surrounding stream reaches with varying levels of intrinsic potential. Model results showed that 33% of streams had moderate or high intrinsic potential for beaver habitat. We found that no site that was classified as having low intrinsic potential had any sign of beavers and that beaver were absent from nearly three quarters of potentially suitable sites, indicating that there are factors preventing the local population from occupying these areas. Of the riparian areas around streams with high intrinsic potential for beaver, 38% are on public lands and 17

Modeling intrinsic potential for beaver (Castor canadensis) habitat to inform restoration and climate change adaptation.

Science.gov (United States)

Dittbrenner, Benjamin J; Pollock, Michael M; Schilling, Jason W; Olden, Julian D; Lawler, Joshua J; Torgersen, Christian E

2018-01-01

Through their dam-building activities and subsequent water storage, beaver have the potential to restore riparian ecosystems and offset some of the predicted effects of climate change by modulating streamflow. Thus, it is not surprising that reintroducing beaver to watersheds from which they have been extirpated is an often-used restoration and climate-adaptation strategy. Identifying sites for reintroduction, however, requires detailed information about habitat factors-information that is not often available at broad spatial scales. Here we explore the potential for beaver relocation throughout the Snohomish River Basin in Washington, USA with a model that identifies some of the basic building blocks of beaver habitat suitability and does so by relying solely on remotely sensed data. More specifically, we developed a generalized intrinsic potential model that draws on remotely sensed measures of stream gradient, stream width, and valley width to identify where beaver could become established if suitable vegetation were to be present. Thus, the model serves as a preliminary screening tool that can be applied over relatively large extents. We applied the model to 5,019 stream km and assessed the ability of the model to correctly predict beaver habitat by surveying for beavers in 352 stream reaches. To further assess the potential for relocation, we assessed land ownership, use, and land cover in the landscape surrounding stream reaches with varying levels of intrinsic potential. Model results showed that 33% of streams had moderate or high intrinsic potential for beaver habitat. We found that no site that was classified as having low intrinsic potential had any sign of beavers and that beaver were absent from nearly three quarters of potentially suitable sites, indicating that there are factors preventing the local population from occupying these areas. Of the riparian areas around streams with high intrinsic potential for beaver, 38% are on public lands and 17% are

Assessing species habitat using Google Street View: a case study of cliff-nesting vultures.

Directory of Open Access Journals (Sweden)

Pedro P Olea

Full Text Available The assessment of a species' habitat is a crucial issue in ecology and conservation. While the collection of habitat data has been boosted by the availability of remote sensing technologies, certain habitat types have yet to be collected through costly, on-ground surveys, limiting study over large areas. Cliffs are ecosystems that provide habitat for a rich biodiversity, especially raptors. Because of their principally vertical structure, however, cliffs are not easy to study by remote sensing technologies, posing a challenge for many researches and managers working with cliff-related biodiversity. We explore the feasibility of Google Street View, a freely available on-line tool, to remotely identify and assess the nesting habitat of two cliff-nesting vultures (the griffon vulture and the globally endangered Egyptian vulture in northwestern Spain. Two main usefulness of Google Street View to ecologists and conservation biologists were evaluated: i remotely identifying a species' potential habitat and ii extracting fine-scale habitat information. Google Street View imagery covered 49% (1,907 km of the roads of our study area (7,000 km². The potential visibility covered by on-ground surveys was significantly greater (mean: 97.4% than that of Google Street View (48.1%. However, incorporating Google Street View to the vulture's habitat survey would save, on average, 36% in time and 49.5% in funds with respect to the on-ground survey only. The ability of Google Street View to identify cliffs (overall accuracy = 100% outperformed the classification maps derived from digital elevation models (DEMs (62-95%. Nonetheless, high-performance DEM maps may be useful to compensate Google Street View coverage limitations. Through Google Street View we could examine 66% of the vultures' nesting-cliffs existing in the study area (n = 148: 64% from griffon vultures and 65% from Egyptian vultures. It also allowed us the extraction of fine-scale features of

Habitat Evaluation Procedures (HEP) Report; Calispell Creek Project, Technical Report 2004-2005.

Energy Technology Data Exchange (ETDEWEB)

Entz, Ray

2005-02-01

On July 13, 2004, the Habitat Evaluation Procedure (HEP) was used to determine baseline habitat suitability on the Calispell Creek property, an acquisition completed by the Kalispel Tribe of Indians in February 2004. Evaluation species and appropriate models include Canada goose, mallard, muskrat, yellow warbler, and white-tailed deer. Habitat Suitability Index (HSI) values were visually estimated and agreed upon by all HEP team members. The Calispell Creek Project provides a total of 138.17 Habitat Units (HUs) for the species evaluated. Emergent wetland habitat provides 5.16 HUs for mallard and muskrat. Grassland provides 132.02 HUs for mallard and Canada goose. Scrub-shrub vegetation provides 0.99 HUs for yellow warbler and white-tailed deer. The objective of using HEP at the Calispell Creek Project and other protected properties is to document the quality and quantity of available habitat for selected wildlife species. In this way, HEP provides information on the relative value of the same area at future points in time so that the effect of management activities on wildlife habitat can be quantified. When combined with other tools, the baseline HEP will be used to determine the most effective on-site management, restoration, and enhancement actions to increase habitat suitability for targeted species. The same process will be replicated every five years to quantitatively evaluate the effectiveness of management strategies in improving and maintaining habitat conditions while providing additional crediting to BPA for enhanced habitat values.

Habitat structure and body size distributions: Cross-ecosystem comparison for taxa with determinate and indeterminate growth

Science.gov (United States)

Nash, Kirsty L.; Allen, Craig R.; Barichievy, Chris; Nystrom, Magnus; Sundstrom, Shana M.; Graham, Nicholas A.J.

2014-01-01

Habitat structure across multiple spatial and temporal scales has been proposed as a key driver of body size distributions for associated communities. Thus, understanding the relationship between habitat and body size is fundamental to developing predictions regarding the influence of habitat change on animal communities. Much of the work assessing the relationship between habitat structure and body size distributions has focused on terrestrial taxa with determinate growth, and has primarily analysed discontinuities (gaps) in the distribution of species mean sizes (species size relationships or SSRs). The suitability of this approach for taxa with indeterminate growth has yet to be determined. We provide a cross-ecosystem comparison of bird (determinate growth) and fish (indeterminate growth) body mass distributions using four independent data sets. We evaluate three size distribution indices: SSRs, species size–density relationships (SSDRs) and individual size–density relationships (ISDRs), and two types of analysis: looking for either discontinuities or abundance patterns and multi-modality in the distributions. To assess the respective suitability of these three indices and two analytical approaches for understanding habitat–size relationships in different ecosystems, we compare their ability to differentiate bird or fish communities found within contrasting habitat conditions. All three indices of body size distribution are useful for examining the relationship between cross-scale patterns of habitat structure and size for species with determinate growth, such as birds. In contrast, for species with indeterminate growth such as fish, the relationship between habitat structure and body size may be masked when using mean summary metrics, and thus individual-level data (ISDRs) are more useful. Furthermore, ISDRs, which have traditionally been used to study aquatic systems, present a potentially useful common currency for comparing body size distributions

Predicting Greater Prairie-Chicken Lek Site Suitability to Inform Conservation Actions.

Directory of Open Access Journals (Sweden)

Torre J Hovick

Full Text Available The demands of a growing human population dictates that expansion of energy infrastructure, roads, and other development frequently takes place in native rangelands. Particularly, transmission lines and roads commonly divide rural landscapes and increase fragmentation. This has direct and indirect consequences on native wildlife that can be mitigated through thoughtful planning and proactive approaches to identifying areas of high conservation priority. We used nine years (2003-2011 of Greater Prairie-Chicken (Tympanuchus cupido lek locations totaling 870 unique leks sites in Kansas and seven geographic information system (GIS layers describing land cover, topography, and anthropogenic structures to model habitat suitability across the state. The models obtained had low omission rates (0.81, indicating high model performance and reliability of predicted habitat suitability for Greater Prairie-Chickens. We found that elevation was the most influential in predicting lek locations, contributing three times more predictive power than any other variable. However, models were improved by the addition of land cover and anthropogenic features (transmission lines, roads, and oil and gas structures. Overall, our analysis provides a hierarchal understanding of Greater Prairie-Chicken habitat suitability that is broadly based on geomorphological features followed by land cover suitability. We found that when land features and vegetation cover are suitable for Greater Prairie-Chickens, fragmentation by anthropogenic sources such as roadways and transmission lines are a concern. Therefore, it is our recommendation that future human development in Kansas avoid areas that our models identified as highly suitable for Greater Prairie-Chickens and focus development on land cover types that are of lower conservation concern.

Assessment of River Habitat Quality in the Hai River Basin, Northern China

Directory of Open Access Journals (Sweden)

Yuekui Ding

2015-09-01

Full Text Available We applied a river habitat quality (RHQ assessment method to the Hai River Basin (HRB; an important economic centre in China; to obtain baseline information for water quality improvement; river rehabilitation; and watershed management. The results of the assessment showed that the river habitat in the HRB is seriously degraded. Specifically; 42.41% of the sites; accounting for a river length of 3.31 × 104 km; were designated poor and bad. Habitat in the plain areas is seriously deteriorated; and nearly 50% of the sites; accounting for a river length of 1.65 × 104 km; had either poor or bad habitats. River habitat degradation was attributable to the limited width of the riparian zone (≤5 m; lower coverage of riparian vegetation (≤40%; artificial land use patterns (public and industrial land; frequent occurrence of farming on the river banks and high volumes of solid waste (nearly 10 m3; single flow channels; and rare aquatic plants (≤1 category. At the regional scale; intensive artificial land use types caused by urbanization had a significant impact on the RHQ in the HRB. RHQ was significantly and negatively correlated with farmland (r = 1.000; p < 0.01 and urban land (r = 0.998; p < 0.05; and was significantly and positively correlated with grassland and woodland (r = 1.000; p < 0.01. Intensive artificial land use; created through urbanization processes; has led to a loss of the riparian zone and its native vegetation; and has disrupted the lateral connectivity of the rivers. The degradation of the already essentially black rivers is exacerbated by poor longitudinal connectivity (index of connectivity is 2.08–16.56; caused by reservoirs and sluices. For river habitat rehabilitation to be successful; land use patterns need to be changed and reservoirs and sluices will have to be regulated.

Habitat Evaluation Procedures (HEP) Report; Carey Creek, Technical Report 2005.

Energy Technology Data Exchange (ETDEWEB)

Entz, Ray

2005-05-01

In August 2002, the Habitat Evaluation Procedure (HEP) was used to determine baseline habitat suitability on the Carey Creek property, an acquisition completed by the Kalispel Tribe of Indians in December 2001. Evaluation species and appropriate models include bald eagle, black-capped chickadee, Canada goose, mallard, yellow warbler, and white-tailed deer. Habitat Suitability Index (HSI) values were visually estimated and agreed upon by all HEP team members. The Carey Creek Project provides a total of 172.95 Habitat Units (HUs) for the species evaluated. Conifer forest habitat provides 4.91 HUs for bald eagle, black-capped chickadee, and white-tailed deer. Forested wetlands provide 52.68 HUs for bald eagle, black-capped chickadee, mallard, and white-tailed deer. Scrub-shrub wetlands provide 2.82 HUs for mallard, yellow warbler and white-tailed deer. Wet meadow and grassland meadow provide 98.13 HUs for mallard and Canada goose. Emergent wetlands provide 11.53 HUs for mallard, muskrat, and Canada goose. Open water provides 2.88 HUs for Canada goose, mallard, and muskrat. The objective of using HEP at the Carey Creek Project and other protected properties is to document the quality and quantity of available habitat for selected wildlife species. In this way, HEP provides information on the relative value of the same area at future points in time so that the effect of management activities on wildlife habitat can be quantified. When combined with other tools, the baseline HEP will be used to determine the most effective on-site management, restoration, and enhancement actions to increase habitat suitability for targeted species. The same process will be replicated every five years to quantitatively evaluate the effectiveness of management strategies in improving and maintaining habitat conditions while providing additional crediting to BPA for enhanced habitat values.

Habitat Evaluation Procedures (HEP) Report; West Beaver Lake Project, Technical Report 2005

Energy Technology Data Exchange (ETDEWEB)

Entz, Ray

2005-05-01

On September 7, 2004, the Habitat Evaluation Procedure (HEP) was used to determine baseline habitat suitability on the West Beaver Lake property, an acquisition completed by the Kalispel Tribe of Indians in September 2004. Evaluation species and appropriate models include bald eagle, black-capped chickadee, mallard, muskrat, and white-tailed deer. Habitat Suitability Index (HSI) values were visually estimated and agreed upon by all HEP team members. The West Beaver Lake Project provides a total of 82.69 Habitat Units (HUs) for the species evaluated. Emergent wetland habitat provides 8.80 HUs for mallard, muskrat, and Canada goose. Conifer forest habitat provides 70.33 HUs for bald eagle, black-capped chickadee, mallard, and white-tailed deer. Open water provides 3.30 HUs for mallard, muskrat, and Canada goose. The objective of using HEP at the West Beaver Lake Project and other protected properties is to document the quality and quantity of available habitat for selected wildlife species. In this way, HEP provides information on the relative value of the same area at future points in time so that the effect of management activities on wildlife habitat can be quantified. When combined with other tools, the baseline HEP will be used to determine the most effective on-site management, restoration, and enhancement actions to increase habitat suitability for targeted species. The same process will be replicated every five years to quantitatively evaluate the effectiveness of management strategies in improving and maintaining habitat conditions while providing additional crediting to BPA for enhanced habitat values.

Suitability assessment of building energy saving technologies for office buildings in cold areas of China based on an assessment framework

International Nuclear Information System (INIS)

Geng, Geng; Wang, Zhaoxia; Zhao, Jing; Zhu, Neng

2015-01-01

Highlights: • An assessment method considering economy, environment and technology is proposed. • Office buildings are classified into 3 types and weights are calculated respectively. • BESTs were summed up as 3 suitability levels. • Recommendations are proposed for adopting in design stage. - Abstract: Blind application and extensive copy of building energy saving technologies have been found very common through investigation in China. Emphases should be put on the suitability assessment when selecting and optimizing building energy saving technologies. This paper created an assessment method, namely an assessment framework to assess the suitability level of building energy saving technologies from a holistic point of view. Fuzzy analytic hierarchy process was adopted. 3 factors and 8 sub-factors were included in the framework. The office buildings were classified into 3 types to calculate weights of factors and sub-factors. The assessment framework was established for each type of office buildings. 20 energy saving technologies from surveyed cases was selected as case study. Ranks of suitability level of the assessment objects were obtained for each type of office buildings. The assessment results could be referred when selecting building energy saving technologies in the design stage

GIS habitat analysis for lesser prairie-chickens in southeastern New Mexico

OpenAIRE

Johnson, Kristine; Neville, Teri B; Neville, Paul

2006-01-01

Abstract Background We conducted Geographic Information System (GIS) habitat analyses for lesser prairie-chicken (LPCH, Tympanuchus pallidicinctus) conservation planning. The 876,799 ha study area included most of the occupied habitat for the LPCH in New Mexico. The objectives were to identify and quantify: 1. suitable LPCH habitat in New Mexico, 2. conversion of native habitats, 3. potential for habitat restoration, and 4. unsuitable habitat available for oil and gas activities. Results We f...

Fish habitat regression under water scarcity scenarios in the Douro River basin

Science.gov (United States)

Segurado, Pedro; Jauch, Eduardo; Neves, Ramiro; Ferreira, Teresa

2015-04-01

Climate change will predictably alter hydrological patterns and processes at the catchment scale, with impacts on habitat conditions for fish. The main goals of this study are to identify the stream reaches that will undergo more pronounced flow reduction under different climate change scenarios and to assess which fish species will be more affected by the consequent regression of suitable habitats. The interplay between changes in flow and temperature and the presence of transversal artificial obstacles (dams and weirs) is analysed. The results will contribute to river management and impact mitigation actions under climate change. This study was carried out in the Tâmega catchment of the Douro basin. A set of 29 Hydrological, climatic, and hydrogeomorphological variables were modelled using a water modelling system (MOHID), based on meteorological data recorded monthly between 2008 and 2014. The same variables were modelled considering future climate change scenarios. The resulting variables were used in empirical habitat models of a set of key species (brown trout Salmo trutta fario, barbell Barbus bocagei, and nase Pseudochondrostoma duriense) using boosted regression trees. The stream segments between tributaries were used as spatial sampling units. Models were developed for the whole Douro basin using 401 fish sampling sites, although the modelled probabilities of species occurrence for each stream segment were predicted only for the Tâmega catchment. These probabilities of occurrence were used to classify stream segments into suitable and unsuitable habitat for each fish species, considering the future climate change scenario. The stream reaches that were predicted to undergo longer flow interruptions were identified and crossed with the resulting predictive maps of habitat suitability to compute the total area of habitat loss per species. Among the target species, the brown trout was predicted to be the most sensitive to habitat regression due to the

Habitat suitability models of mountain ungulates: identifying potential areas for conservation

Czech Academy of Sciences Publication Activity Database

Paudel, Prakash K.; Hais, M.; Kindlmann, Pavel

2015-01-01

Roč. 54, apr (2015), s. 37 ISSN 1021-5506 R&D Projects: GA MŠk(CZ) LO1415; GA MŠk LC06073; GA ČR GB14-36098G Institutional support: RVO:67179843 Keywords : capricornis thar * habitat model * Midhills * Muntiacus muntjak * Naemorhedus goral * Nepal Subject RIV: EH - Ecology, Behaviour Impact factor: 0.885, year: 2015

An integrated assessment of Porcupine caribou seasonal distribution, movements, and habitat preferences for regional land use planning in northern Yukon Territory, Canada

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John L. Ryder

2007-04-01

Full Text Available This study was undertaken to improve understanding of Porcupine caribou herd distribution, movements, and habitat preferences to assist with developing a regional land use plan for the North Yukon Planning Region, Yukon Territory. Three different methods were used to identify current and historical patterns of caribou distribution and habitat preferences within the region to prioritize conservation areas. Two of the approaches focused on incorporating information on caribou distribution and migrations from scientific and local knowledge, while the third focused on identifying and mapping habitats suitable for supporting caribou. Local knowledge dating back to the 1930s and two decades of satellite telemetry data confirmed that most of the planning region is used by the Porcupine caribou herd and highlighted areas of concentrated use. Maps of suitable winter habitat derived from expert opinion ratings of habitat use did not agree with the other information sources. The local knowledge and satellite telemetry analyses were used to identify spatially explicit priority areas for caribou conservation and the results were applied to develop conservation recommendations for a draft regional land use plan. The plan will be submitted to government approval bodies for review in the spring of 2007. The success in implementing conservation strategies for the Porcupine caribou herd will be reviewed and evaluated following adoption of a final approved plan.

Habitat suitability of Anopheles vector species and association with human malaria in the Atlantic Forest in south-eastern Brazil.

Science.gov (United States)

Laporta, Gabriel Zorello; Ramos, Daniel Garkauskas; Ribeiro, Milton Cezar; Sallum, Maria Anice Mureb

2011-08-01

Every year, autochthonous cases of Plasmodium vivax malaria occur in low-endemicity areas of Vale do Ribeira in the south-eastern part of the Atlantic Forest, state of São Paulo, where Anopheles cruzii and Anopheles bellator are considered the primary vectors. However, other species in the subgenus Nyssorhynchus of Anopheles (e.g., Anopheles marajoara) are abundant and may participate in the dynamics of malarial transmission in that region. The objectives of the present study were to assess the spatial distribution of An. cruzii, An. bellator and An. marajoara and to associate the presence of these species with malaria cases in the municipalities of the Vale do Ribeira. Potential habitat suitability modelling was applied to determine both the spatial distribution of An. cruzii, An. bellator and An. marajoara and to establish the density of each species. Poisson regression was utilized to associate malaria cases with estimated vector densities. As a result, An. cruzii was correlated with the forested slopes of the Serra do Mar, An. bellator with the coastal plain and An. marajoara with the deforested areas. Moreover, both An. marajoara and An. cruzii were positively associated with malaria cases. Considering that An. marajoara was demonstrated to be a primary vector of human Plasmodium in the rural areas of the state of Amapá, more attention should be given to the species in the deforested areas of the Atlantic Forest, where it might be a secondary vector.

Habitat risk assessment for regional ocean planning in the U.S. Northeast and Mid-Atlantic.

Science.gov (United States)

Wyatt, Katherine H; Griffin, Robert; Guerry, Anne D; Ruckelshaus, Mary; Fogarty, Michael; Arkema, Katie K

2017-01-01

Coastal habitats provide important benefits to people, including habitat for species targeted by fisheries and opportunities for tourism and recreation. Yet, such human activities also can imperil these habitats and undermine the ecosystem services they provide to people. Cumulative risk assessment provides an analytical framework for synthesizing the influence of multiple stressors across habitats and decision-support for balancing human uses and ecosystem health. To explore cumulative risk to habitats in the U.S. Northeast and Mid-Atlantic Ocean Planning regions, we apply the open-source InVEST Habitat Risk Assessment model to 13 habitats and 31 stressors in an exposure-consequence framework. In doing so, we advance the science priorities of EBM and both regional planning bodies by synthesizing the wealth of available data to improve our understanding of human uses and how they affect marine resources. We find that risk to ecosystems is greatest first, along the coast, where a large number of stressors occur in close proximity and secondly, along the continental shelf, where fewer, higher consequence activities occur. Habitats at greatest risk include soft and hard-bottom nearshore areas, tidal flats, soft-bottom shelf habitat, and rocky intertidal zones-with the degree of risk varying spatially. Across all habitats, our results indicate that rising sea surface temperatures, commercial fishing, and shipping consistently and disproportionally contribute to risk. Further, our findings suggest that management in the nearshore will require simultaneously addressing the temporal and spatial overlap as well as intensity of multiple human activities and that management in the offshore requires more targeted efforts to reduce exposure from specific threats. We offer a transparent, generalizable approach to evaluating cumulative risk to multiple habitats and illustrate the spatially heterogeneous nature of impacts along the eastern Atlantic coast and the importance of

Deep Space Habitat Concept Demonstrator

Science.gov (United States)

Bookout, Paul S.; Smitherman, David

2015-01-01

This project will develop, integrate, test, and evaluate Habitation Systems that will be utilized as technology testbeds and will advance NASA's understanding of alternative deep space mission architectures, requirements, and operations concepts. Rapid prototyping and existing hardware will be utilized to develop full-scale habitat demonstrators. FY 2014 focused on the development of a large volume Space Launch System (SLS) class habitat (Skylab Gen 2) based on the SLS hydrogen tank components. Similar to the original Skylab, a tank section of the SLS rocket can be outfitted with a deep space habitat configuration and launched as a payload on an SLS rocket. This concept can be used to support extended stay at the Lunar Distant Retrograde Orbit to support the Asteroid Retrieval Mission and provide a habitat suitable for human missions to Mars.

Oil sands terrestrial habitat and risk modeling for disturbance and reclamation - Phase I report

Energy Technology Data Exchange (ETDEWEB)

Welham, C. [FORRx Consulting Inc., Belcarra, BC (Canada)

2010-11-15

The main purpose of this study is to build a framework that includes risk management and strategic decision-making to assess the impact of natural and industrial disturbance on ecosystem products and services and on the existence of habitat for terrestrial species in Alberta's Lower Athabasca planning region. This will include an evaluation of the impact of disturbance, conservation and reclamation activities associated with oil sands development both at the lease and regional levels. The basecase scenario, established in Phase I, includes a dendrochronology study of the link between climate and tree growth in the sub boreal region that comprises oil sands mining, an analysis of habitat availability for 10 wildlife species compared with reclamation activities on the Kearl Lake mine, and an examination of the potential for development of high levels of water stress in recent reclamation plantations at the Kearl Lake mine. Four tree species of the subboreal forests of Alberta and Saskatchewan were considered for the dendrochronology study: the white spruce or Picea glauca, the black spruce or Picea mariana, the jack pine or Pinus banksiana, and the trembling aspen or Populus tremuloides. This study shows that the water stress observed during the year has restricted the radial growth of white spruce and a link has been established between radial growth and increasing season precipitation and summer temperatures. The purposes of the habitat suitability analysis were to list habitats suitability models that could be applied to Alberta boreal forests, distinguish the parameters used in those models that can be simulated with an ecosystem simulation model, simulate the reclamation prescriptions detailed in the Kearl Lake EIA documents with the ecosystem simulation model and generate output suitable for populating each habitat suitability model. The establishment of ecologically viable reclamation plans in the oil sands region can be hard to manage regarding the

Habitat Evaluation Procedures (HEP) Report; Upper Trimble Project, Technical Report 2004-2005.

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Entz, Ray

2005-02-01

On July 13, 2004, the Habitat Evaluation Procedure (HEP) was used to determine baseline habitat suitability on the Upper Trimble property, an acquisition completed by the Kalispel Tribe of Indians in March 2004. Evaluation species and appropriate models include bald eagle, black-capped chickadee, Canada goose, mallard, muskrat, yellow warbler, and white-tailed deer. Habitat Suitability Index (HSI) values were visually estimated and agreed upon by all HEP team members. The Upper Trimble Project provides a total of 250.67 Habitat Units (HUs) for the species evaluated. Wet meadow provides 136.92 HUs for mallard, muskrat, and Canada goose. Mixed forest habitat provides 111.88 HUs for bald eagle, black-capped chickadee, mallard, and white-tailed deer. Scrub-shrub vegetation provides 1.87 HUs for yellow warbler, and white-tailed deer. The objective of using HEP at the Upper Trimble Project and other protected properties is to document the quality and quantity of available habitat for selected wildlife species. In this way, HEP provides information on the relative value of the same area at future points in time so that the effect of management activities on wildlife habitat can be quantified. When combined with other tools, the baseline HEP will be used to determine the most effective on-site management, restoration, and enhancement actions to increase habitat suitability for targeted species. The same process will be replicated every five years to quantitatively evaluate the effectiveness of management strategies in improving and maintaining habitat conditions while providing additional crediting to BPA for enhanced habitat values.

Identifying Areas Suitable for the Occurrence of Rift Valley Fever in North Africa: Implications for Surveillance.

Science.gov (United States)

Arsevska, E; Hellal, J; Mejri, S; Hammami, S; Marianneau, P; Calavas, D; Hénaux, V

2016-12-01

Rift Valley fever (RVF) is a vector-borne zoonotic disease that has caused widespread outbreaks throughout Africa and the Arabian Peninsula, with serious consequences for livestock-based economies and public health. Although there have never been any reports of RVF in Morocco, Algeria, Tunisia and Libya, it is a priority disease in the Maghreb, due to the threat of introduction of the virus through transboundary livestock movements or infected mosquito vectors. However, the implementation of surveillance activities and early warning contingency plans requires better knowledge of the epidemiological situation. We conducted a multicriteria decision analysis, integrating host distribution with a combination of important ecological factors that drive mosquito abundance, to identify hotspots and suitable time periods for RVF enzootic circulation (i.e. stable transmission at a low to moderate level for an extended period of time) and an RVF epizootic event (i.e. a sudden occurrence of a large number of infected animals over a large geographic area) in the Maghreb. We also modelled vector species distribution using available information on vector presence and habitat preference. We found that the northern regions of the Maghreb were moderately suitable for RVF enzootics, but highly suitable for RVF epizootics. The vector species distribution model identified these regions as the most favourable mosquito habitats. Due to the low density of animal hosts and arid conditions, the desert region showed low RVF suitability, except in oases. However, the presence of competent vectors in putative unsuitable areas underlines the need for further assessments of mosquito habitat preference. This study produced monthly RVF suitability maps useful for animal health managers and veterinary services involved in designing risk-based surveillance programmes. The suitability maps can be further enhanced using existing country-specific sources of information and by incorporating knowledge

Use of functional traits to assess changes in stream fish assemblages across a habitat gradient

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Mariela Domiciano Ribeiro

Full Text Available Abstract Functional traits are important for understanding the links between species occurrence and environmental conditions. Identifying these links makes it possible to predict changes in species composition within communities under specific environmental conditions. We used functional traits related to habitat use and trophic ecology in order to assess the changes in fish community composition between streams with varying habitat structure. The relationship between the species traits and habitat characteristics was analyzed using an RLQ ordination analysis. Although species were widely distributed in habitats with different structures, physical conditions did favor some species based on their functional characteristics. Eight functional traits were found to be associated with stream habitat structure, allowing us to identify traits that may predict the susceptibility of fish species to physical habitat degradation.

Determining Home Range and Preferred Habitat of Feral Horses on the Nevada National Security Site Using Geographic Information Systems

Energy Technology Data Exchange (ETDEWEB)

Burns, Ashley V. [Univ. of Denver, CO (United States)

2014-05-30

Feral horses (Equus caballus) are free-roaming descendants of domesticated horses and legally protected by the Wild and Free-Roaming Horses and Burros Act of 1971, which mandates how feral horses and burros should be managed and protected on federal lands. Using a geographic information system to determine the home range and suitable habitat of feral horses on the federally managed Nevada National Security Site can enable wildlife biologists in making best management practice recommendations. Home range was estimated at 88.1 square kilometers. Site suitability was calculated for elevation, forage, slope, water presence and horse observations. These variables were combined in successive iterations into one polygon. Suitability rankings established that 85 square kilometers are most suitable habitat, with 2,052 square kilometers of good habitat 1,252 square kilometers of fair habitat and 122 square kilometers of least suitable habitat.

TINGKAT KESESUAIAN SUAKA MARGASATWA CIKEPUH SEBAGAI HABITAT KEDUA BADAK JAWA (Rhinoceros sondaicus Desmarest, 1822

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Ribai .

2016-01-01

Full Text Available Javan rhino (Rhinoceros sondaicus is one of the rarest species in the world so categorized as critically endangered by IUCN. Survival of the rhino in Ujung Kulon National Park is threatened by a variety of factors that could cause these extinct animals, such as: invasion langkap, competition with the bulls, and inbreeding. The strategy should be promoted in maintaining and developing population that is making a second habitat. The purpose of this research is to know the suitability level of Cikepuh Wildlife Reserves (CWR as javan rhino’s second habitat. The method used is the field observations. Results showed that the CWR have high suitability as javan rhino’s second habitat with an area of 6886.4 ha (84.72% CWR. Cikepuh Wildlife Reserves components that have a high potential as second habitat are on aspects altitude, air temperature, humidity, water availability, and soil pH. Strategies that can be done in improving the suitability of the CWR as second habitat includ: create pools ofthe rhino, planting food plants that have a high palatability and reduce human pressure through strict enforcement, public education, standardized regular patrols, rehabilitation and enrichment of degraded area, livestock expenses , and review the MoU regarding the use of the area as a military Cikepuh SM. Keywords: Cikepuh Wildlife Reserve, habitat suitability, javan rhino, second habitat

Defining landscape resistance values in least-cost connectivity models for the invasive grey squirrel: a comparison of approaches using expert-opinion and habitat suitability modelling.

Science.gov (United States)

Stevenson-Holt, Claire D; Watts, Kevin; Bellamy, Chloe C; Nevin, Owen T; Ramsey, Andrew D

2014-01-01

Least-cost models are widely used to study the functional connectivity of habitat within a varied landscape matrix. A critical step in the process is identifying resistance values for each land cover based upon the facilitating or impeding impact on species movement. Ideally resistance values would be parameterised with empirical data, but due to a shortage of such information, expert-opinion is often used. However, the use of expert-opinion is seen as subjective, human-centric and unreliable. This study derived resistance values from grey squirrel habitat suitability models (HSM) in order to compare the utility and validity of this approach with more traditional, expert-led methods. Models were built and tested with MaxEnt, using squirrel presence records and a categorical land cover map for Cumbria, UK. Predictions on the likelihood of squirrel occurrence within each land cover type were inverted, providing resistance values which were used to parameterise a least-cost model. The resulting habitat networks were measured and compared to those derived from a least-cost model built with previously collated information from experts. The expert-derived and HSM-inferred least-cost networks differ in precision. The HSM-informed networks were smaller and more fragmented because of the higher resistance values attributed to most habitats. These results are discussed in relation to the applicability of both approaches for conservation and management objectives, providing guidance to researchers and practitioners attempting to apply and interpret a least-cost approach to mapping ecological networks.

Defining landscape resistance values in least-cost connectivity models for the invasive grey squirrel: a comparison of approaches using expert-opinion and habitat suitability modelling.

Directory of Open Access Journals (Sweden)

Claire D Stevenson-Holt

Full Text Available Least-cost models are widely used to study the functional connectivity of habitat within a varied landscape matrix. A critical step in the process is identifying resistance values for each land cover based upon the facilitating or impeding impact on species movement. Ideally resistance values would be parameterised with empirical data, but due to a shortage of such information, expert-opinion is often used. However, the use of expert-opinion is seen as subjective, human-centric and unreliable. This study derived resistance values from grey squirrel habitat suitability models (HSM in order to compare the utility and validity of this approach with more traditional, expert-led methods. Models were built and tested with MaxEnt, using squirrel presence records and a categorical land cover map for Cumbria, UK. Predictions on the likelihood of squirrel occurrence within each land cover type were inverted, providing resistance values which were used to parameterise a least-cost model. The resulting habitat networks were measured and compared to those derived from a least-cost model built with previously collated information from experts. The expert-derived and HSM-inferred least-cost networks differ in precision. The HSM-informed networks were smaller and more fragmented because of the higher resistance values attributed to most habitats. These results are discussed in relation to the applicability of both approaches for conservation and management objectives, providing guidance to researchers and practitioners attempting to apply and interpret a least-cost approach to mapping ecological networks.

An artificial water body provides habitat for an endangered estuarine seahorse species

Science.gov (United States)

Claassens, Louw

2016-10-01

Anthropogenic development, especially the transformation of natural habitats to artificial, is a growing concern within estuaries and coastal areas worldwide. Thesen Islands marina, an artificial water body, added 25 ha of new estuarine habitat to the Knysna Estuary in South Africa, home to the Knysna seahorse. This study aimed to answer: (I) Can an artificial water body provide suitable habitat for an endangered seahorse species? And if so (II) what characteristics of this new habitat are important in terms of seahorse utilization? Four major habitat types were identified within the marina canals: (I) artificial reno mattress (wire baskets filled with rocks); (II) Codium tenue beds; (III) mixed vegetation on sediment; and (IV) barren canal floor. Seahorses were found throughout the marina system with significantly higher densities within the reno mattress habitat. The artificial water body, therefore, has provided suitable habitat for Hippocampus capensis, a noteworthy finding in the current environment of coastal development and the increasing shift from natural to artificial.

The importance of historical land use in the maintenance of early successional habitat for a threatened rattlesnake

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Eric M. McCluskey

2018-01-01

Full Text Available Understanding how historic habitat changes have impacted species and searching the past for clues to better understand the current plight of threatened species can help inform and improve future conservation efforts. We coupled species distribution modeling with historical imagery analysis to assess how changes in land use/land cover have influenced the distribution of eastern massasauga rattlesnake (Sistrurus catenatus, a federally threatened species, and its habitat in northeastern Ohio over the past ∼75 years. We also examined land use/land cover changes throughout southern Michigan for a broader perspective on the influence of historical processes on contemporary habitat. There was a pronounced shift in northeastern Ohio land cover from 1938 to 2011 with forest cover becoming the predominant land cover type as agricultural fields were abandoned and succession occurred. Most known eastern massasauga locations in the area were at some point used for agriculture and higher habitat suitability values were associated with agricultural fields that were eventually abandoned. We observed more stable habitat conditions across southern Michigan populations indicating agricultural abandonment was not as necessary for habitat creation in this part of their range. We present a new approach for linking historical landscapes to present day habitat suitability models; permitting inferences on how prior land use/land cover states have influenced the current distribution of species and their habitats. We demonstrate how agricultural abandonment was an important source of early successional habitat for a species that requires an open canopy, a finding applicable to a broad array of species with similar habitat requirements. Keywords: Eastern massasauga, Agriculture, Aerial photography, Maxent

Modeling habitat suitability of the invasive clam Corbicula fluminea in a Neotropical shallow lagoon, southern Brazil

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T. C. L. Silveira

Full Text Available Abstract This study aimed to model the habitat suitability for an invasive clam Corbicula fluminea in a coastal shallow lagoon in the southern Neotropical region (–30.22, –50.55. The lagoon (19km2, maximum deep 2.5m was sampled with an Ekman dredge in an orthogonal matrix comprising 84 points. At each sampling point, were obtained environmental descriptors as depth, organic matter content (OMC, average granulometry (Avgran, and the percentage of sand (Pcsand. Prediction performance of Generalized Linear Models (GLM, Generalized Additive Models (GAM and Boosted Regression Tree (BRT were compared. Also, niche overlapping with other native clam species (Castalia martensi, Neocorbicula limosa and Anodontites trapesialis was examined. A BRT model with 1400 trees was selected as the best model, with cross-validated correlation of 0.82. The relative contributions of predictors were Pcsand-42.6%, OMC-35.8%, Avgran-10.9% and Depth-10.8%. Were identified that C. fluminea occur mainly in sandy sediments with few organic matter, in shallow areas nor by the shore. The PCA showed a wide niche overlap with the native clam species C. martensi, N. limosa and A. trapesialis.

Relevance of multiple spatial scales in habitat models: A case study with amphibians and grasshoppers

Science.gov (United States)

Altmoos, Michael; Henle, Klaus

2010-11-01

Habitat models for animal species are important tools in conservation planning. We assessed the need to consider several scales in a case study for three amphibian and two grasshopper species in the post-mining landscapes near Leipzig (Germany). The two species groups were selected because habitat analyses for grasshoppers are usually conducted on one scale only whereas amphibians are thought to depend on more than one spatial scale. First, we analysed how the preference to single habitat variables changed across nested scales. Most environmental variables were only significant for a habitat model on one or two scales, with the smallest scale being particularly important. On larger scales, other variables became significant, which cannot be recognized on lower scales. Similar preferences across scales occurred in only 13 out of 79 cases and in 3 out of 79 cases the preference and avoidance for the same variable were even reversed among scales. Second, we developed habitat models by using a logistic regression on every scale and for all combinations of scales and analysed how the quality of habitat models changed with the scales considered. To achieve a sufficient accuracy of the habitat models with a minimum number of variables, at least two scales were required for all species except for Bufo viridis, for which a single scale, the microscale, was sufficient. Only for the European tree frog ( Hyla arborea), at least three scales were required. The results indicate that the quality of habitat models increases with the number of surveyed variables and with the number of scales, but costs increase too. Searching for simplifications in multi-scaled habitat models, we suggest that 2 or 3 scales should be a suitable trade-off, when attempting to define a suitable microscale.

Fish thermal habitat current use and simulation of thermal habitat availability in lakes of the Argentine Patagonian Andes under climate change scenarios RCP 4.5 and RCP 8.5.

Science.gov (United States)

Vigliano, Pablo H; Rechencq, Magalí M; Fernández, María V; Lippolt, Gustavo E; Macchi, Patricio J

2018-09-15

Habitat use in relation to the thermal habitat availability and food source as a forcing factor on habitat selection and use of Percichthys trucha (Creole perch), Oncorhynchus mykiss (rainbow trout), Salmo trutta (brown trout) and Salvelinus fontinalis (brook trout) were determined as well as future potential thermal habitat availability for these species under climate change scenarios Representative Concentration Pathways 4.5 and 8.5. This study was conducted in three interconnected lakes of Northern Patagonia (Moreno Lake system). Data on fish abundance was obtained through gill netting and hydroacoustics, and thermal profiles and fish thermal habitat suitability index curves were used to identify current species-specific thermal habitat use. Surface air temperatures from the (NEX GDDP) database for RCP scenarios 4.5 and 8.5 were used to model monthly average temperatures of the water column up to the year 2099 for all three lakes, and to determine potential future habitat availability. In addition, data on fish diet were used to determine whether food could act as a forcing factor in current habitat selection. The four species examined do not use all the thermally suitable habitats currently available to them in the three lakes, and higher fish densities are not necessarily constrained to their "fundamental thermal niches" sensu Magnuson et al. (1979), as extensive use is made of less suitable habitats. This is apparently brought about by food availability acting as a major forcing factor in habitat selection and use. Uncertainties related to the multidimensionality inherent to habitat selection and climate change imply that fish resource management in Patagonia will not be feasible through traditional incremental policies and strategic adjustments based on short-term predictions, but will have to become highly opportunistic and adaptive. Copyright © 2018 Elsevier B.V. All rights reserved.

Delineating priority habitat areas for the conservation of Andean bears in northern Ecuador

Science.gov (United States)

Peralvo, M.F.; Cuesta, F.; Van Manen, F.

2005-01-01

We sought to identify priority areas for the conservation of Andean bear (Tremarctos ornatus) habitat in the northern portion of the eastern Andean cordillera in Ecuador. The study area included pa??ramo and montane forest habitats within the Antisana and Cayambe-Coca ecological reserves, and unprotected areas north of these reserves with elevations ranging from 1,800 to 4,300 m. We collected data on bear occurrence along 53 transects during 2000-01 in the Oyacachi River basin, an area of indigenous communities within the Cayambe-Coca Ecological Reserve. We used those data and a set of 7 environmental variables to predict suitability of Andean bear habitat using Mahalanobis distance, a multivariate measure of dissimilarity. The Mahalanobis distance values were classified into 5 classes of habitat suitability and generalized to a resolution of 1,650-m ?? 1,650-m grid cells. Clusters of grid cells with high suitability values were delineated from the generalized model and denned as important habitat areas (IHAs) for conservation. The IHAs were ranked using a weighted index that included factors of elevation range, influence from disturbed areas, and current conservation status. We identified 12 IHAs, which were mainly associated with pa??ramo and cloud forest habitats; 2 of these areas have high conservation priorities because they are outside existing reserves and close to areas of human pressure. The distribution of the IHAs highlighted the role of human land use as the main source of fragmentation of Andean bear habitat in this region, emphasizing the importance of preserving habitat connectivity to allow the seasonal movements among habitat types that we documented for this species. Furthermore, the existence of areas with high habitat suitability close to areas of intense human use indicates the importance of bear-human conflict management as a critical Andean bear conservation strategy. We suggest that a promising conservation opportunity for this species is

Habitat quality influences population distribution, individual space use and functional responses in habitat selection by a large herbivore.

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Bjørneraas, Kari; Herfindal, Ivar; Solberg, Erling Johan; Sæther, Bernt-Erik; van Moorter, Bram; Rolandsen, Christer Moe

2012-01-01

Identifying factors shaping variation in resource selection is central for our understanding of the behaviour and distribution of animals. We examined summer habitat selection and space use by 108 Global Positioning System (GPS)-collared moose in Norway in relation to sex, reproductive status, habitat quality, and availability. Moose selected habitat types based on a combination of forage quality and availability of suitable habitat types. Selection of protective cover was strongest for reproducing females, likely reflecting the need to protect young. Males showed strong selection for habitat types with high quality forage, possibly due to higher energy requirements. Selection for preferred habitat types providing food and cover was a positive function of their availability within home ranges (i.e. not proportional use) indicating functional response in habitat selection. This relationship was not found for unproductive habitat types. Moreover, home ranges with high cover of unproductive habitat types were larger, and smaller home ranges contained higher proportions of the most preferred habitat type. The distribution of moose within the study area was partly related to the distribution of different habitat types. Our study shows how distribution and availability of habitat types providing cover and high-quality food shape ungulate habitat selection and space use.

Ultra-Fine Scale Spatially-Integrated Mapping of Habitat and Occupancy Using Structure-From-Motion.

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Philip McDowall

Full Text Available Organisms respond to and often simultaneously modify their environment. While these interactions are apparent at the landscape extent, the driving mechanisms often occur at very fine spatial scales. Structure-from-Motion (SfM, a computer vision technique, allows the simultaneous mapping of organisms and fine scale habitat, and will greatly improve our understanding of habitat suitability, ecophysiology, and the bi-directional relationship between geomorphology and habitat use. SfM can be used to create high-resolution (centimeter-scale three-dimensional (3D habitat models at low cost. These models can capture the abiotic conditions formed by terrain and simultaneously record the position of individual organisms within that terrain. While coloniality is common in seabird species, we have a poor understanding of the extent to which dense breeding aggregations are driven by fine-scale active aggregation or limited suitable habitat. We demonstrate the use of SfM for fine-scale habitat suitability by reconstructing the locations of nests in a gentoo penguin colony and fitting models that explicitly account for conspecific attraction. The resulting digital elevation models (DEMs are used as covariates in an inhomogeneous hybrid point process model. We find that gentoo penguin nest site selection is a function of the topography of the landscape, but that nests are far more aggregated than would be expected based on terrain alone, suggesting a strong role of behavioral aggregation in driving coloniality in this species. This integrated mapping of organisms and fine scale habitat will greatly improve our understanding of fine-scale habitat suitability, ecophysiology, and the complex bi-directional relationship between geomorphology and habitat use.

The micro-habitat methodology. Application protocols

Energy Technology Data Exchange (ETDEWEB)

Sabaton, C; Valentin, S; Souchon, Y

1995-06-01

A strong need has been felt for guidelines to help various entities in applying the micro-habitat methodology, particularly in impact studies on hydroelectric installations. CEMAGREF and Electricite de France have developed separately two protocols with five major steps: reconnaissance of the river, selection of representative units to be studied in greater depth, morpho-dynamic measurements at one or more rates of discharge and hydraulic modeling, coupling of hydraulic and biological models, calculation of habitat-quality scores for fish, analysis of results. The two approaches give very comparable results and are essentially differentiated by the hydraulic model used. CEMAGREF uses a one-dimensional model requiring measurements at only one discharge rate. Electricite de France uses a simplified model based on measurements at several rates of discharge. This approach is possible when discharge can be controlled in the study area during data acquisition, as is generally the case downstream of hydroelectric installations. The micro-habitat methodology is now a fully operational tool with which to study changes in fish habitat quality in relation to varying discharge. It provides an element of assessment pertinent to the choice of instreaming flow to be maintained downstream of a hydroelectric installation; this information is essential when the flow characteristics (velocity, depth) and the nature of the river bed are the preponderant factors governing habitat suitability for trout or salmon. The ultimate decision must nonetheless take into account any other potentially limiting factors for the biocenoses on the one hand, and the target water use objectives on the other. In many cases, compromises must be found among different uses, different species and different stages in the fish development cycle. (Abstract Truncated)

Exploring the Application of Optical Remote Sensing as a Method to Estimate the Depth of Backwater Nursery Habitats of the Colorado Pikeminnow

Energy Technology Data Exchange (ETDEWEB)

Hamada, Yuki [Argonne National Lab. (ANL), Argonne, IL (United States); LaGory, Kirk E. [Argonne National Lab. (ANL), Argonne, IL (United States)

2016-02-01

Low-velocity channel-margin habitats serve as important nursery habitats for the endangered Colorado pikeminnow (Ptychocheilus lucius) in the middle Green River between Jensen and Ouray, Utah. These habitats, known as backwaters, are associated with emergent sand bars, and are shaped and reformed annually by peak flows. A recent synthesis of information on backwater characteristics and the factors that influence inter-annual variability in those backwaters (Grippo et al. 2015) evaluated detailed survey information collected annually since 2003 on a relatively small sample of backwaters, as well as reach-wide evaluations of backwater surface area from aerial and satellite imagery. An approach is needed to bridge the gap between these detailed surveys, which estimate surface area, volume, and depth, and the reach-wide assessment of surface area to enable an assessment of the amount of habitat that meets the minimum depth requirements for suitable habitat.

Using occupancy and population models to assess habitat conservation opportunities for an isolated carnivore population

Science.gov (United States)

Wayne Spencer; Heather Rustigian-Romsos; James Strittholt; Robert Scheller; William Zielinski; Richard Truex

2011-01-01

An isolated population of the fisher (Martes pennanti) in the southern Sierra Nevada, California, is threatened by small size and habitat alteration from wildfires, fuels management, and other factors. We assessed the population’s status and conservation options for its habitat using a spatially explicit population model coupled with a...

Analyzing the Correlation between Deer Habitat and the Component of the Risk for Lyme Disease in Eastern Ontario, Canada: A GIS-Based Approach

Directory of Open Access Journals (Sweden)

Dongmei Chen

2015-01-01

Full Text Available Lyme borreliosis, caused by the bacterium, Borrelia burgdorferi, is an emerging vector-borne infectious disease in Canada. According to the Public Health Agency of Canada (PHAC, by the year 2020, 80% of Canadians will live in Lyme endemic areas. An understanding of the association of Ixodes scapularis, the main vector of Lyme disease, with it hosts is a fundamental component in assessing changes in the spatial distribution of human risk for Lyme disease. Through the application of Geographic Information System (GIS mapping methods and spatial analysis techniques, this study examines the population dynamics of the black-legged Lyme tick and its primary host, the white-tailed deer, in eastern Ontario, Canada. By developing a habitat suitability model through a GIS-based multi-criteria decision making (MCDM analysis, the relationship of the deer habitat suitability map was generated and the results were compared with deer harvest data. Tick submission data collected from two public health units between 2006 and 2012 were used to explore the relationship between endemic ticks and deer habitat suitability in eastern Ontario. The positive correlation demonstrated between the deer habitat suitability model and deer harvest data allows us to further analyze the association between deer habitat and black-legged ticks in our study area. Our results revealed that the high tick submission number corresponds with the high suitability. These results are useful for developing management strategies that aim to prevent Lyme from becoming a threat to public health in Canada. Further studies are required to investigate how tick survival, behaviour and seasonal activity may change with projected climate change.

Habitat selection of Tragulus napu and Tragulus javanicus using MaxEnt analysis

Science.gov (United States)

Taher, Taherah Mohd; Lihan, Tukimat; Mustapha, Muzzneena Ahmad; Nor, Shukor Mohd

2018-04-01

Large areas are converted into commercial land use such as agriculture and urban as a result from the increasing economic and population demand. This situation is largely affecting wildlife and its habitat. Malaysia as one of the largest oil palm-producing countries, should take precaution into conserving its forest and wildlife diversity. Although big mammal such as elephant and tiger are significant for wildlife diversity, medium and small mammals also contribute to the biological richness in Malaysia. This study aims to predict suitable habitat of medium mammal, Tragulus napu and Tragulus javanicus in the study area and identify its habitat characteristics. The method applied in this study uses maximum entropy (MaxEnt) modeling which utilized species distribution data and selected environmental variables to alienate potential habitat in the study area. The characteristic of the habitat was identified from the result of MaxEnt analysis. This method of habitat modeling shows different extent of predicted suitable habitat in the study area of both species in which Tragulus napu has a limited distribution compared to Tragulus javanicus. However, some characteristics are similar in both habitats. The knowledge on species habitat characteristics is important to predict wildlife habitat in order to make best decision on land use management and conservation.

Assessment of Suitability of Wood Fibres of Four Nigerian Fruit ...

African Journals Online (AJOL)

Wood fibres of four fruit trees of Nigeria commonly found in Nsukka metropolis were studied and assessed for their suitability for paper-making. These trees include Mangifera indica, Anacardium occidentale, Persea americana and Dacryodes edulis. The parameters used in the study were the fibre dimensions and derived ...

Natural Propagation and Habitat Improvement, Volume I, Oregon, Supplement C, White River Habitat Inventory, 1983 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Heller, David

1984-04-01

More than 130 miles of stream fish habitat was inventoried and evaluated on the Mt. Hood National Forest during the first year of this multi-year project. First year tasks included field inventory and evaluation of habitat conditions on the White River and tributary streams thought to have the highest potential for supporting anadromous fish populations. All streams inventoried were located on the Mt. Hood National Forest. The surveyed area appears to contain most of the high quality anadromous fish habitat in the drainage. Habitat conditions appear suitable for steelhead, coho, and chinook salmon, and possibly sockeye. One hundred and twenty-four miles of potential anadromous fish habitat were identifed in the survey. Currently, 32 miles of this habitat would be readily accessible to anadromous fish. An additional 72 miles of habitat could be accessed with only minor passage improvement work. About 20 miles of habitat, however, will require major investment to provide fish passage. Three large lakes (Boulder, 14 acres; Badger, 45 acres; Clear, 550 acres) appear to be well-suited for rearing anadromous fish, although passage enhancement would be needed before self-sustaining runs could be established in any of the lakes.

Habitat evaluation for outbreak of Yangtze voles (Microtus fortis) and management implications.

Science.gov (United States)

Xu, Zhenggang; Zhao, Yunlin; Li, Bo; Zhang, Meiwen; Shen, Guo; Wang, Yong

2015-05-01

Rodent pests severely damage agricultural crops. Outbreak risk models of rodent pests often do not include sufficient information regarding geographic variation. Habitat plays an important role in rodent-pest outbreak risk, and more information about the relationship between habitat and crop protection is urgently needed. The goal of the present study was to provide an outbreak risk map for the Dongting Lake region and to understand the relationship between rodent-pest outbreak variation and habitat distribution. The main rodent pests in the Dongting Lake region are Yangtze voles (Microtus fortis). These pests cause massive damage in outbreak years, most notably in 2007. Habitat evaluation and ecological details were obtained by analyzing the correlation between habitat suitability and outbreak risk, as indicated by population density and historical events. For the source-sink population, 96.18% of Yangtze vole disaster regions were covered by a 10-km buffer zone of suitable habitat in 2007. Historical outbreak frequency and peak population density were significantly correlated with the proportion of land covered by suitable habitat (r = 0.68, P = 0.04 and r = 0.76, P = 0.03, respectively). The Yangtze vole population tends to migrate approximately 10 km in outbreak years. Here, we propose a practical method for habitat evaluation that can be used to create integrated pest management plans for rodent pests when combined with basic information on the biology, ecology and behavior of the target species. © 2014 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and Wiley Publishing Asia Pty Ltd.

Seasonal Habitat Patterns of Japanese Common Squid (Todarodes Pacificus Inferred from Satellite-Based Species Distribution Models

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Irene D. Alabia

2016-11-01

Full Text Available The understanding of the spatio-temporal distributions of the species habitat in the marine environment is central to effectual resource management and conservation. Here, we examined the potential habitat distributions of Japanese common squid (Todarodes pacificus in the Sea of Japan during a four-year period. The seasonal patterns of preferential habitat were inferred from species distribution models, built using squid occurrences detected from night-time visible images and remotely-sensed environmental factors. The predicted squid habitat (i.e., areas with high habitat suitability revealed strong seasonal variability, characterized by a reduction of potential habitat, confined off of the southern part of the basin during the winter–spring period (December–May. Apparent expansion of preferential habitat occurred during summer–autumn months (June–November, concurrent with the formation of highly suitable habitat patches in certain regions of the Sea of Japan. These habitat distribution patterns were in response to changes in oceanographic conditions and synchronous with seasonal migration of squid. Moreover, the most important variables regulating the spatio-temporal patterns of suitable habitat were sea surface temperature, depth, sea surface height anomaly, and eddy kinetic energy. These variables could affect the habitat distributions through their impacts on growth and survival of squid, local nutrient transport, and the availability of favorable spawning and feeding grounds.

Identifying Impacts of Hydropower Regulation on Salmonid Habitats to Guide River Restoration for Existing Schemes and Mitigate Adverse Effects of Future Developments

Science.gov (United States)

Buddendorf, B.; Geris, J.; Malcolm, I.; Wilkinson, M.; Soulsby, C.

2015-12-01

A decrease in longitudinal connectivity in riverine ecosystems resulting from the construction of transverse barriers has been identified as a major threat to biodiversity. For example, Atlantic Salmon (Salmo salar) have a seasonal variety of hydraulic habitat requirements for their different life stages. However, hydropower impoundments impact the spatial and temporal connectivity of natural habitat along many salmon rivers in ways that are not fully understood. Yet, these changes may affect the sustainability of habitat at local and regional scales and so ultimately the conservation of the species. Research is therefore needed both to aid the restoration and management of rivers impacted by previous hydropower development and guide new schemes to mitigate potentially adverse effects. To this end we assessed the effects of hydropower development on the flow related habitat conditions for different salmon life stages in Scottish rivers at different spatial scales. We used GIS techniques to map the changes in structural connectivity at regional scales, applying a weighting for habitat quality. Next, we used hydrological models to simulate past and present hydrologic conditions that in turn drive reach-scale hydraulic models to assess the impacts of regulation on habitat suitability in both space and time. Preliminary results indicate that: 1) impacts on connectivity depend on the location of the barrier within the river network; 2) multiple smaller barriers may have a potentially lower impact than a single larger barrier; 3) there is a relationship between habitat and connectivity where losing less but more suitable habitat potentially has a disproportionally large impact; 4) the impact of flow regulation can lead to a deterioration of habitat quality, though the effects are spatially variable and the extent of the impact depends on salmon life stage. This work can form a basis for using natural processes to perform targeted and cost-effective restoration of rivers.

Global patterns of fragmentation and connectivity of mammalian carnivore habitat

OpenAIRE

Crooks, Kevin R.; Burdett, Christopher L.; Theobald, David M.; Rondinini, Carlo; Boitani, Luigi

2011-01-01

Although mammalian carnivores are vulnerable to habitat fragmentation and require landscape connectivity, their global patterns of fragmentation and connectivity have not been examined. We use recently developed high-resolution habitat suitability models to conduct comparative analyses and to identify global hotspots of fragmentation and connectivity for the world's terrestrial carnivores. Species with less fragmentation (i.e. more interior high-quality habitat) had larger geographical ranges...

Combining a dispersal model with network theory to assess habitat connectivity.

Science.gov (United States)

Lookingbill, Todd R; Gardner, Robert H; Ferrari, Joseph R; Keller, Cherry E

2010-03-01

Assessing the potential for threatened species to persist and spread within fragmented landscapes requires the identification of core areas that can sustain resident populations and dispersal corridors that can link these core areas with isolated patches of remnant habitat. We developed a set of GIS tools, simulation methods, and network analysis procedures to assess potential landscape connectivity for the Delmarva fox squirrel (DFS; Sciurus niger cinereus), an endangered species inhabiting forested areas on the Delmarva Peninsula, USA. Information on the DFS's life history and dispersal characteristics, together with data on the composition and configuration of land cover on the peninsula, were used as input data for an individual-based model to simulate dispersal patterns of millions of squirrels. Simulation results were then assessed using methods from graph theory, which quantifies habitat attributes associated with local and global connectivity. Several bottlenecks to dispersal were identified that were not apparent from simple distance-based metrics, highlighting specific locations for landscape conservation, restoration, and/or squirrel translocations. Our approach links simulation models, network analysis, and available field data in an efficient and general manner, making these methods useful and appropriate for assessing the movement dynamics of threatened species within landscapes being altered by human and natural disturbances.

Readability and suitability assessment of patient education materials in rheumatic diseases.

Science.gov (United States)

Rhee, Rennie L; Von Feldt, Joan M; Schumacher, H Ralph; Merkel, Peter A

2013-10-01

Web-based patient education materials and printed pamphlets are frequently used by providers to inform patients about their rheumatic disease. Little attention has been given to the readability and appropriateness of patient materials. The objective of this study was to examine the readability and suitability of commonly used patient education materials for osteoarthritis (OA), rheumatoid arthritis, systemic lupus erythematosus, and vasculitis. Five or 6 popular patient resources for each disease were chosen for evaluation. Readability was measured using the Flesch-Kincaid reading grade level and suitability was determined by the Suitability Assessment of Materials (SAM), a score that considers characteristics such as content, graphics, layout/topography, and cultural appropriateness. Three different reviewers rated the SAM score and means were used in the analysis. Twenty-three resources written on the 4 diseases were evaluated. The education material for all 4 diseases studied had readability above the eighth-grade level and readability did not differ among the diseases. Only 5 of the 23 resources received superior suitability scores, and 3 of these 5 resources were written for OA. All 4 diseases received adequate suitability scores, with OA having the highest mean suitability score. Most patient education materials for rheumatic diseases are written at readability levels above the recommended sixth-grade reading level and have only adequate suitability. Developing more appropriate educational resources for patients with rheumatic diseases may improve patient comprehension. Copyright © 2013 by the American College of Rheumatology.

Long-term habitat changes in a protected area: Implications for herpetofauna habitat management and restoration.

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Chantel E Markle

Full Text Available Point Pelee National Park, located at the southern-most tip of Canada's mainland, historically supported a large number of herpetofauna species; however, despite nearly a century of protection, six snake and five amphibian species have disappeared, and remaining species-at-risk populations are thought to be in decline. We hypothesized that long-term changes in availability and distribution of critical habitat types may have contributed to the disappearance of herpetofauna. To track habitat changes we used aerial image data spanning 85 years (1931-2015 and manually digitized and classified image data using a standardized framework. Change-detection analyses were used to evaluate the relative importance of proportionate loss and fragmentation of 17 habitat types. Marsh habitat diversity and aquatic connectivity has declined since 1931. The marsh matrix transitioned from a graminoid and forb shallow marsh interspersed with water to a cattail dominated marsh, altering critical breeding, foraging, and overwintering habitat. Reduced diversity of marsh habitats appears to be linked to the expansion of invasive Phragmites australis, which invaded prior to 2000. Loss of open habitats such as savanna and meadow has reduced availability of high quality thermoregulation habitat for reptiles. Restoration of the northwestern region and tip of Point Pelee National Park to a mixed landscape of shallow wetlands (cattail, graminoid, forb, open water and eradication of dense Phragmites stands should improve habitat diversity. Our results suggest that long-term landscape changes resulting from habitat succession and invasive species can negatively affect habitat suitability for herpetofauna and protection of land alone does not necessarily equate to protection of sensitive herpetofauna.

Long-term habitat changes in a protected area: Implications for herpetofauna habitat management and restoration.

Science.gov (United States)

Markle, Chantel E; Chow-Fraser, Gillian; Chow-Fraser, Patricia

2018-01-01

Point Pelee National Park, located at the southern-most tip of Canada's mainland, historically supported a large number of herpetofauna species; however, despite nearly a century of protection, six snake and five amphibian species have disappeared, and remaining species-at-risk populations are thought to be in decline. We hypothesized that long-term changes in availability and distribution of critical habitat types may have contributed to the disappearance of herpetofauna. To track habitat changes we used aerial image data spanning 85 years (1931-2015) and manually digitized and classified image data using a standardized framework. Change-detection analyses were used to evaluate the relative importance of proportionate loss and fragmentation of 17 habitat types. Marsh habitat diversity and aquatic connectivity has declined since 1931. The marsh matrix transitioned from a graminoid and forb shallow marsh interspersed with water to a cattail dominated marsh, altering critical breeding, foraging, and overwintering habitat. Reduced diversity of marsh habitats appears to be linked to the expansion of invasive Phragmites australis, which invaded prior to 2000. Loss of open habitats such as savanna and meadow has reduced availability of high quality thermoregulation habitat for reptiles. Restoration of the northwestern region and tip of Point Pelee National Park to a mixed landscape of shallow wetlands (cattail, graminoid, forb, open water) and eradication of dense Phragmites stands should improve habitat diversity. Our results suggest that long-term landscape changes resulting from habitat succession and invasive species can negatively affect habitat suitability for herpetofauna and protection of land alone does not necessarily equate to protection of sensitive herpetofauna.

Habitat split and the global decline of amphibians.

Science.gov (United States)

Becker, Carlos Guilherme; Fonseca, Carlos Roberto; Haddad, Célio Fernando Baptista; Batista, Rômulo Fernandes; Prado, Paulo Inácio

2007-12-14

The worldwide decline in amphibians has been attributed to several causes, especially habitat loss and disease. We identified a further factor, namely "habitat split"-defined as human-induced disconnection between habitats used by different life history stages of a species-which forces forest-associated amphibians with aquatic larvae to make risky breeding migrations between suitable aquatic and terrestrial habitats. In the Brazilian Atlantic Forest, we found that habitat split negatively affects the richness of species with aquatic larvae but not the richness of species with terrestrial development (the latter can complete their life cycle inside forest remnants). This mechanism helps to explain why species with aquatic larvae have the highest incidence of population decline. These findings reinforce the need for the conservation and restoration of riparian vegetation.

Subterranean systems provide a suitable overwintering habitat for Salamandra salamandra

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Monika Balogová

2017-09-01

Full Text Available The fire salamander (Salamandra salamandra has been repeatedly noted to occur in natural and artificial subterranean systems. Despite the obvious connection of this species with underground shelters, their level of dependence and importance to the species is still not fully understood. In this study, we carried out long-term monitoring based on the capture-mark-recapture method in two wintering populations aggregated in extensive underground habitats. Using the POPAN model we found the population size in a natural shelter to be more than twice that of an artificial underground shelter. Survival and recapture probabilities calculated using the Cormack-Jolly-Seber model were very constant over time, with higher survival values in males than in females and juveniles, though in terms of recapture probability, the opposite situation was recorded. In addition, survival probability obtained from Cormack-Jolly-Seber model was higher than survival from POPAN model. The observed bigger population size and the lower recapture rate in the natural cave was probably a reflection of habitat complexity. Our study showed that regular visits are needed to detect the true significance of underground shelters for fire salamanders. The presence of larvae was recorded in both wintering sites, especially in bodies of water near the entrance. On the basis of previous and our observations we incline to the view, that karst areas can induce not only laying in underground shelters but also group wintering in this species. Our study highlights the strong connection of the life cycle of fire salamanders with underground shelters and their essential importance for the persistence of some populations during unfavourable conditions and breeding activity. In addition, the study introduces the POPAN and Cormac-Jolly-Seber models for estimating of population size, survival and recapture probability in wintering populations of the species, which could provide important information

Historical habitat connectivity affects current genetic structure in a grassland species

Czech Academy of Sciences Publication Activity Database

Münzbergová, Zuzana; Cousins, S.A.O.; Herben, Tomáš; Plačková, Ivana; Mildén, M.; Ehrlén, J.

2013-01-01

Roč. 15, č. 1 (2013), s. 195-202 ISSN 1435-8603 Institutional research plan: CEZ:AV0Z60050516 Institutional support: RVO:67985939 Keywords : Beals index * habitat isolation * habitat suitability Subject RIV: EF - Botanics Impact factor: 2.405, year: 2013

The importance of distance to resources in the spatial modelling of bat foraging habitat.

Directory of Open Access Journals (Sweden)

Ana Rainho

Full Text Available Many bats are threatened by habitat loss, but opportunities to manage their habitats are now increasing. Success of management depends greatly on the capacity to determine where and how interventions should take place, so models predicting how animals use landscapes are important to plan them. Bats are quite distinctive in the way they use space for foraging because (i most are colonial central-place foragers and (ii exploit scattered and distant resources, although this increases flying costs. To evaluate how important distances to resources are in modelling foraging bat habitat suitability, we radio-tracked two cave-dwelling species of conservation concern (Rhinolophus mehelyi and Miniopterus schreibersii in a Mediterranean landscape. Habitat and distance variables were evaluated using logistic regression modelling. Distance variables greatly increased the performance of models, and distance to roost and to drinking water could alone explain 86 and 73% of the use of space by M. schreibersii and R. mehelyi, respectively. Land-cover and soil productivity also provided a significant contribution to the final models. Habitat suitability maps generated by models with and without distance variables differed substantially, confirming the shortcomings of maps generated without distance variables. Indeed, areas shown as highly suitable in maps generated without distance variables proved poorly suitable when distance variables were also considered. We concluded that distances to resources are determinant in the way bats forage across the landscape, and that using distance variables substantially improves the accuracy of suitability maps generated with spatially explicit models. Consequently, modelling with these variables is important to guide habitat management in bats and similarly mobile animals, particularly if they are central-place foragers or depend on spatially scarce resources.

3.10. Habitat restoration and creation

OpenAIRE

2016-01-01

1.12.1 Terrestrial habitat Based on the collated evidence, what is the current assessment of the effectiveness of interventions for terrestrial habitat restoration and creation? Beneficial ● Replant vegetation Likely to be beneficial ● Clear vegetation● Create artificial hibernacula or aestivation sites● Create refuges● Restore habitat connectivity Unknown effectiveness (limited evidence) ● Change mowing regime No evidence found (no assessment) ● Create habitat connectivity Beneficial Repla...

Assessment and mapping of tradeoffs land uses in the Orangutan habitat: A case Pongo pygmeus pygmeus habitat of West Kalimantan

Science.gov (United States)

Siregar, P. G.; Supriatna, J.; Koestoer, R. H.; Harmantyo, D.

2017-07-01

This study aims to analyse trade-offs among 6 (six) types of dominant land uses to consider Orangutan livelihood and landscape sustainability. The results of this study assists landscape's planners and policy makers for selecting development scenarios as well as policy within the landscape, especially to reduce human and wildlife conflict as impact of development. This study was conducted in Orangutan sub species Pongo pygmeus pygmeus habitat in West Kalimantan, Indonesia. Net present value analysis was applied to identify economic profit of land uses and also perspective of expert judgment was applied to identify suitability of the land uses to Orangutan livelihood. The study shows that palm oil plantation was the dominant land use type in non-forest area category and natural forest is in forest area category within the site. Palm oil contributed highest economic profit (average IDR 11 Million per year) compared to other land use types, and thus the worst land use type for supporting Orangutan conservation; index suitability for Orangutan achieved only 21.8. The development of agroforestry which planted more than 3 valuable economic commodities is used as an alternative in forest buffer area development that can provide better gain for economic and Orangutan conservation with index suitability for Orangutan was 43.5. In achieving sustainability at the landscape level, it needs to consider the sustainability of the umbrella species, such as Orangutan. The existence of the umbrella species would also protect other biodiversity, forest and its environmental services.

Hydrologic characteristics of freshwater mussel habitat: novel insights from modeled flows

Science.gov (United States)

Drew, C. Ashton; Eddy, Michele; Kwak, Thomas J.; Cope, W. Gregory; Augspurger, Tom

2018-01-01

The ability to model freshwater stream habitat and species distributions is limited by the spatially sparse flow data available from long-term gauging stations. Flow data beyond the immediate vicinity of gauging stations would enhance our ability to explore and characterize hydrologic habitat suitability. The southeastern USA supports high aquatic biodiversity, but threats, such as landuse alteration, climate change, conflicting water-resource demands, and pollution, have led to the imperilment and legal protection of many species. The ability to distinguish suitable from unsuitable habitat conditions, including hydrologic suitability, is a key criterion for successful conservation and restoration of aquatic species. We used the example of the critically endangered Tar River Spinymussel (Parvaspina steinstansana) and associated species to demonstrate the value of modeled flow data (WaterFALL™) to generate novel insights into population structure and testable hypotheses regarding hydrologic suitability. With ordination models, we: 1) identified all catchments with potentially suitable hydrology, 2) identified 2 distinct hydrologic environments occupied by the Tar River Spinymussel, and 3) estimated greater hydrological habitat niche breadth of assumed surrogate species associates at the catchment scale. Our findings provide the first demonstrated application of complete, continuous, regional modeled hydrologic data to freshwater mussel distribution and management. This research highlights the utility of modeling and data-mining methods to facilitate further exploration and application of such modeled environmental conditions to inform aquatic species management. We conclude that such an approach can support landscape-scale management decisions that require spatial information at fine resolution (e.g., enhanced National Hydrology Dataset catchments) and broad extent (e.g., multiple river basins).

Assessing the Amazon Cloud Suitability for CLARREO's Computational Needs

Science.gov (United States)

Goldin, Daniel; Vakhnin, Andrei A.; Currey, Jon C.

2015-01-01

In this document we compare the performance of the Amazon Web Services (AWS), also known as Amazon Cloud, with the CLARREO (Climate Absolute Radiance and Refractivity Observatory) cluster and assess its suitability for computational needs of the CLARREO mission. A benchmark executable to process one month and one year of PARASOL (Polarization and Anistropy of Reflectances for Atmospheric Sciences coupled with Observations from a Lidar) data was used. With the optimal AWS configuration, adequate data-processing times, comparable to the CLARREO cluster, were found. The assessment of alternatives to the CLARREO cluster continues and several options, such as a NASA-based cluster, are being considered.

Proceedings of a workshop on the development and evaluation of habitat suitability criteria: A compilation of papers and discussions presented at Colorado State University, Fort Collins, Colorado, December 8-12, 1986

Science.gov (United States)

Bovee, Ken; Zuboy, J.R.

1988-01-01

The development of reliable habitat suitability criteria is critical to the successful implementation of the Instream Flow Incremental Methodology (IFIM), or any other habitat based evaluation technology. It is also a fascinating topic of research, for several reasons. First, the “science” of habitat quantification is relatively young. Descriptions of habitat use and partitioning can be traced back to Darwin, if not further. Attempts to actually quantify habitat use can be found predominantly during the last two decades, with most of the activity occurring in about the last five years. Second, this work is challenging because we are usually working with fish or some other organism that lives out of sight in an environment that is foreign to humans. Most of the data collection techniques that have been developed for standard fisheries work are unsuited, without modification, for criteria development. These factors make anyone involved in this type of research a pioneer, of sorts. Pioneers often make new and wonderful discoveries, but they also sometimes get lost. In our opinion, however, there is an even more rewarding aspect to criteria development research. It seems that the field of biology has tended to become increasingly clinical over the years. Criteria development demands the unobtrusive observation of organisms in their natural environment, a fact that allows the biological to be a naturalist and still get paid for it. The relative youth and importance of habitat quantification have resulted in rapid advancements in the state of the art. The expansion of methods is vividly demonstrated simply by comparing the two Instream Flow Information Papers written on the subject in 1978 and in 1986. One of the missions of the Aquatic Systems Branch (formerly the Instream Flow Group) is to serve as a clearinghouse for new techniques and methods. In keeping with this role, a workshop was conducted during December 1986 to discuss current and newly evolving methods

Fall and winter microhabitat use and suitability for spring chinook salmon parr in a U.S. Pacific Northwest River

Science.gov (United States)

Favrot, Scott D.; Jonasson, Brian C.; Peterson, James T.

2018-01-01

Habitat degradation has been implicated as a primary threat to Pacific salmon Oncorhynchus spp. Habitat restoration and conservation are key toward stemming population declines; however, winter microhabitat use and suitability knowledge are lacking for small juvenile salmonids. Our objective was to characterize microhabitat use and suitability for spring Chinook Salmon Oncorhynchus tshawytscha parr during fall and winter. Using radiotelemetry techniques during October–February (2009–2011), we identified fall and winter microhabitat use by spring Chinook Salmon parr in Catherine Creek, northeastern Oregon. Tagged fish occupied two distinct gradient reaches (moderate and low). Using a mixed‐effects logistic regression resource selection function (RSF) model, we found evidence that microhabitat use was similar between free‐flowing and surface ice conditions. However, habitat use shifted between seasons; most notably, there was greater use of silt substrate and areas farther from the bank during winter. Between gradients, microhabitat use differed with greater use of large wood (LW) and submerged aquatic vegetation in the low‐gradient reach. Using a Bayesian RSF approach, we developed gradient‐specific habitat suitability criteria. Throughout the study area, deep depths and slow currents were most suitable, with the exception of the low‐gradient reach where moderate depths were optimal. Near‐cover coarse and fine substrates were most suitable in the moderate‐ and low‐gradient reaches, respectively. Near‐bank LW was most suitable throughout the study area. Multivariate principal component analyses (PCA) indicated co‐occurring deep depths supporting slow currents near cover were intensively occupied in the moderate‐gradient reach. In the low‐gradient reach, PCA indicated co‐occurring moderate depths, slow currents, and near‐bank cover were most frequently occupied. Our study identified suitable and interrelated microhabitat

Daytime habitat selection for juvenile parr brown trout (Salmo trutta in small lowland streams

Directory of Open Access Journals (Sweden)

Conallin J.

2014-03-01

Full Text Available Physical habitat is important in determining the carrying capacity of juvenile brown trout, and within freshwater management. Summer daytime physical habitat selection for the parr lifestage (7–20 cm juvenile brown trout (Salmo trutta was assessed in 6 small lowland streams. Habitat preference was determined for the four variables; water velocity, water depth, substrate and cover, and the preferences for physical habitat selection were expressed in terms of habitat suitability indices (HSI’s. The statistical confidence of HSI’s was evaluated using power analysis. It was found that a minimum of 22 fish observations was needed to have statistical confidence in the HSIs for water depth, and a minimum of 92 fish observations for water velocity during daytime summer conditions. Generally parr were utilising the deeper habitats, indicating preference for deeper water. Cover was also being selected for at all sites, but selection was inconsistent among sites for the variables substrate and velocity. The results indicate that during daytime summer conditions water depth is a significant variable for parr habitat selection in these small lowland streams, with cover also being important. Therefore, daytime refugia may be a critical limiting factor for parr in small lowland streams, and important for stream management actions under the Water Framework Directive.

[Ecology suitability study of Ephedra intermedia].

Science.gov (United States)

Ma, Xiao-Hui; Lu, You-Yuan; Huang, De-Dong; Zhu, Tian-Tian; Lv, Pei-Lin; Jin, Ling

2017-06-01

The study aims at predicting ecological suitability of Ephedra intermedia in China by using maximum entropy Maxent model combined with GIS, and finding the main ecological factors affecting the distribution of E. intermedia suitability in appropriate growth area. Thirty-eight collected samples of E. intermedia and E. intermedia and 116 distribution information from CVH information using ArcGIS technology were analyzed. MaxEnt model was applied to forecast the E. intermedia in our country's ecology. E. intermedia MaxEnt ROC curve model training data and testing data sets the AUC value was 0.986 and 0.958, respectively, which were greater than 0.9, tending to be 1.The calculated E. intermedia habitat suitability by the model showed a high accuracy and credibility, which indicated that MaxEnt model could well predict the potential distribution area of E. intermedia in China. Copyright© by the Chinese Pharmaceutical Association.

Habitat Evaluation Procedures (HEP) Report; Tacoma Creek South Project, Technical Report 2003-2005.

Energy Technology Data Exchange (ETDEWEB)

Entz, Ray

2005-02-01

On July 6, 2004, the Habitat Evaluation Procedure (HEP) was used to determine baseline habitat suitability on the Tacoma Creek South property, an acquisition completed by the Kalispel Tribe of Indians in June 2004. Evaluation species and appropriate models include bald eagle, black-capped chickadee, Canada goose, mallard, muskrat, yellow warbler, and white-tailed deer. Habitat Suitability Index (HSI) values were visually estimated and agreed upon by all HEP team members. The Tacoma Creek South Project provides a total of 190.79 Habitat Units (HUs) for the species evaluated. Emergent wetlands provide 20.51 HUs for Canada goose, mallard, and muskrat. Grassland provides 1.65 HUs for Canada goose and mallard. Scrub-shrub vegetation provides 11.76 HUs for mallard, yellow warbler, and white-tailed deer. Conifer forest habitat provides 139.92 HUs for bald eagle, black-capped chickadee, and white-tailed deer. Deciduous forest also provides 19.15 HUs for bald eagle, black-capped chickadee, mallard, and white-tailed deer. The objective of using HEP at the Tacoma Creek South Project and other protected properties is to document the quality and quantity of available habitat for selected wildlife species. In this way, HEP provides information on the relative value of the same area at future points in time so that the effect of management activities on wildlife habitat can be quantified. When combined with other tools, the baseline HEP will be used to determine the most effective on-site management, restoration, and enhancement actions to increase habitat suitability for targeted species. The same process will be replicated every five years to quantitatively evaluate the effectiveness of management strategies in improving and maintaining habitat conditions while providing additional crediting to BPA for enhanced habitat values.

Assessment of chevron dikes for the enhancement of physical-aquatic habitat within the Middle Mississippi River, USA

Science.gov (United States)

Remo, Jonathan W. F.; Khanal, Anish; Pinter, Nicholas

2013-09-01

Blunt-nosed chevron dikes, a new invention now being widely constructed on the Middle Mississippi River (MMR), have been justified as a tool for enhancing physical-aquatic habitat. Chevron dikes were initially designed to concentrate flow, induce channel scour, and thus facilitate river navigation. More recently, these structures have been justified, in part, for promoting habitat heterogeneity. The ability of chevrons to create and diversify physical-aquatic habitat, however, has not been empirically evaluated. To assess the ability of chevrons to create and diversify physical-aquatic habitat, we compiled hydrologic and geospatial data for three channel reference conditions along a 2.0 km (∼140 ha) reach of the MMR where three chevrons were constructed in late 2007. We used the hydrologic and hydraulic data to construct detailed 2-D hydrodynamic models for three reference condition: historic (circa 1890), pre-chevron, and post-chevron channel conditions. These models documented changes in depths and flow dynamics for a wide range of in-channel discharges. Depth-velocity habitat classes were used to assess change in physical-aquatic habitat patches and spatial statistical tools in order to evaluate the reach-scale habitat patch diversity. Comparisons of pre- and post-chevron conditions revealed increases in deep to very deep (>3.0 m) areas of slow moving (3.0 m], low velocity [<0.6 m/s]). Chevron construction also created some (0.8-3.8 ha) shallow-water habitat (0-1.5 m depth with a 0-0.6 m/s velocity) for flows ⩽2.0 × MAF and contributed to an 8-35% increase in physical-aquatic-habitat diversity compared to pre-chevron channel conditions. However, modeling of the historic reference condition (less engineered channel, circa 1890) revealed that the historical physical-aquatic-habitat mosaic consisted of a wider and shallower channel with: 45-390% more shallow-water habitat (2.4-11.0 ha) and 22-83% more physical-aquatic-habitat diversity, but little over

Characterization and Monitoring Data for Evaluating Constructed Emergent Sandbar Habitat in the Missouri River Mainstem

Energy Technology Data Exchange (ETDEWEB)

Duberstein, Corey A.; Downs, Janelle L.

2008-11-06

Emergent sandbar habitat (ESH) in the Missouri River Mainstem System is a critical habitat element for several federally listed bird species: the endangered interior least tern (Sterna antillarum) and the threatened Northern Great Plains piping plover (Charadrius melodus). The Army Corps of Engineers (Corps) provides the primary operational management of the Missouri River and is responsible under the Endangered Species Act (ESA) to take actions within its authorities to conserve listed species. To comply with the 2000 USFWS BiOp and the 2003 amended USFWS BiOp, the Corps has created habitats below Gavins Point Dam using mechanical means. Initial monitoring indicates that constructed sandbars provide suitable habitat features for nesting and foraging least terns and piping plovers. Terns and plovers are using constructed sandbars and successfully reproducing at or above levels stipulated in the BiOp. However, whether such positive impacts will persist cannot yet be adequately assessed at this time.

Habitat suitability—density relationship in an endangered woodland species: the case of the Blue Chaffinch (Fringilla polatzeki

Directory of Open Access Journals (Sweden)

Luis M. Carrascal

2017-09-01

Full Text Available Background Understanding constraints to the distribution of threatened species may help to ascertain whether there are other suitable sectors for reducing the risks associated with species that are recorded in only one protected locality, and to inform about the suitability of other areas for reintroduction or translocation programs. Methods We studied the Gran Canaria blue chaffinch (Fringilla polatzeki, a habitat specialist endemic of the Canary Islands restricted to the pine forest of Inagua, the only area where the species has been naturally present as a regular breeder in the last 25 years. A suitability distribution model using occurrences with demographic relevance (i.e., nest locations of successful breeding attempts analysed using boosted classification trees was built considering orographic, climatic and habitat structure predictors. By means of a standardized survey program we monitored the yearly abundance of the species in 100 sectors since the declaration of Inagua as a Strict Nature Reserve in 1994. Results The variables with the highest relative importance in blue chaffinch habitat preferences were pine height, tree cover, altitude, and rainfall during the driest trimester (July–September. The observed local abundance of the blue chaffinch in Inagua (survey data was significantly correlated with habitat suitability derived from modelling the location of successful nesting attempts (using linear and quantile regressions. The outcomes of the habitat suitability model were used to quantify the suitability of other natural, historic, pine forests of Gran Canaria. Tamadaba is the forest with most suitable woodland patches for the species. We estimated a population size of 195–430 blue chaffinches in Inagua since 2011 (95% CI, the smallest population size of a woodland passerine in the Western Palearctic. Discussion Habitat suitability obtained from modelling the location of successful breeding attempts is a good surrogate of the

Fish habitat mitigation measures for hydrotechnical projects

International Nuclear Information System (INIS)

McPhail, G.D.; MacMillan, D.B.; Katopodis, C.

1992-01-01

In recent years, the identification and mitigation of environmental impacts of hydrotechnical projects, particularly on fish and fish habitats, have become a major component of project planning and design. Potential impacts to fish and fish habitat may include increased fish mortality, decreased species diversity, and loss or decreases in fish production due to loss of habitat or alteration of its suitability. These impacts arise from flooding of riverine habitat, alteration of flow quantity and distribution, changes in morphology, and alteration of water quality, including suspended sediments, temperature, dissolved oxygen, and mercury. The results of a study for the Canadian Federal Department of Fisheries and Oceans Central and Arctic Region, examining fish habitat mitigation techniques for their applicability to hydrotechnical projects in Canada are summarized. The requirements for achievement and verification of the no net loss policy for a project are discussed. 10 refs., 2 tabs

Land Suitability Assessment And Precision Farming Prospects For ...

African Journals Online (AJOL)

The soils on the farm were sampled and profiles classified using South African Binomial system of soil classification. The farm was divided into suitability classes of highly suitable (S1), suitable (S2), and unsuitable (N1), and permanently unsuitable (N2) classes. Maize-soybean suitability maps were produced based on soil ...

A novel approach to assessing environmental disturbance based on habitat selection by zebra fish as a model organism.

Science.gov (United States)

Araújo, Cristiano V M; Griffith, Daniel M; Vera-Vera, Victoria; Jentzsch, Paul Vargas; Cervera, Laura; Nieto-Ariza, Beatriz; Salvatierra, David; Erazo, Santiago; Jaramillo, Rusbel; Ramos, Luis A; Moreira-Santos, Matilde; Ribeiro, Rui

2018-04-01

Aquatic ecotoxicity assays used to assess ecological risk assume that organisms living in a contaminated habitat are forcedly exposed to the contamination. This assumption neglects the ability of organisms to detect and avoid contamination by moving towards less disturbed habitats, as long as connectivity exists. In fluvial systems, many environmental parameters vary spatially and thus condition organisms' habitat selection. We assessed the preference of zebra fish (Danio rerio) when exposed to water samples from two western Ecuadorian rivers with apparently distinct disturbance levels: Pescadillo River (highly disturbed) and Oro River (moderately disturbed). Using a non-forced exposure system in which water samples from each river were arranged according to their spatial sequence in the field and connected to allow individuals to move freely among samples, we assayed habitat selection by D. rerio to assess environmental disturbance in the two rivers. Fish exposed to Pescadillo River samples preferred downstream samples near the confluence zone with the Oro River. Fish exposed to Oro River samples preferred upstream waters. When exposed to samples from both rivers simultaneously, fish exhibited the same pattern of habitat selection by preferring the Oro River samples. Given that the rivers are connected, preference for the Oro River enabled us to predict a depression in fish populations in the Pescadillo River. Although these findings indicate higher disturbance levels in the Pescadillo River, none of the physical-chemical variables measured was significantly correlated with the preference pattern towards the Oro River. Non-linear spatial patterns of habitat preference suggest that other environmental parameters like urban or agricultural contaminants play an important role in the model organism's habitat selection in these rivers. The non-forced exposure system represents a habitat selection-based approach that can serve as a valuable tool to unravel the factors

Lake Roosevelt Rainbow Trout : Habitat/Passage Improvement Project Annual Report 2000.

Energy Technology Data Exchange (ETDEWEB)

Sear, Sheri

2001-02-01

Lake Franklin D. Roosevelt was created with the completion of the Grand Coulee Dam in 1942. The lake stretches 151 miles up-stream to the International border between the United States and Canada at the 49th parallel. Increased recreational use, subsistence and sport fishing has resulted in intense interest and possible exploitation of the resources within the lake. Previous studies of the lake and its fishery have been limited. Early studies indicate that natural reproduction within the lake and tributaries are not sufficient to support a rainbow trout (Onchoryhnchus mykiss) fishery (Scholz et. al., 1988). These studies indicate that the rainbow trout population may be limited by lack of suitable habitat for spawning and rearing (Scholz et. al., 1988). The initial phase of this project (Phase I, baseline data collection- 1990-91) was directed at the assessment of limiting factors such as quality and quantity of available spawning gravel, identification of passage barriers, and assessment of other limiting factors. Population estimates were conducted using the Seber/LeCren removal/depletion method. After the initial assessment of stream parameters, several streams were selected for habitat/passage improvement projects (Phase II, implementation-1992-96). At the completion of project habitat improvements, the final phase (Phase III, monitoring) began. This phase will assess changes and gauge the success achieved through the improvements. The objective of the project is to correct passage barriers and improve habitat conditions of selected tributaries to Lake Roosevelt for adfluvial rainbow trout that utilize tributary streams for spawning and rearing. Streams with restorable habitats were selected for improvements. Completion of improvement efforts should increase the adfluvial rainbow trout contribution to the resident fishery in Lake Roosevelt. Three co-operating agencies, the Confederated Tribes of the Colville Reservation (CCT), the Spokane Tribe of Indians (STI

Lake Roosevelt Rainbow Trout : Habitat/Passage Improvement Project Annual Report 1999.

Energy Technology Data Exchange (ETDEWEB)

Jones, Charles D.

2000-02-01

Lake Franklin D. Roosevelt was created with the completion of the Grand Coulee Dam in 1942. The lake stretches 151 miles up-stream to the International border between the United States and Canada at the 49th parallel. Increased recreational use, subsistence and sport fishing has resulted in intense interest and possible exploitation of the resources within the lake. Previous studies of the lake and its fishery have been limited. Early studies indicate that natural reproduction within the lake and tributaries are not sufficient to support a rainbow trout (Onchoryhnchus mykiss) fishery (Scholz et. al., 1988). These studies indicate that the rainbow trout population may be limited by lack of suitable habitat for spawning and rearing (Scholz et. al., 1988). The initial phase of this project (Phase I, baseline data collection- 1990-91) was directed at the assessment of limiting factors such as quality and quantity of available spawning gravel, identification of passage barriers, and assessment of other limiting factors. Population estimates were conducted using the Seber/LeCren removal/depletion method. After the initial assessment of stream parameters, several streams were selected for habitat/passage improvement projects (Phase II, implementation-1992-96). At the completion of project habitat improvements, the final phase (Phase III, monitoring) began. This phase will assess changes and gauge the success achieved through the improvements. The objective of the project is to correct passage barriers and improve habitat conditions of selected tributaries to Lake Roosevelt for adfluvial rainbow trout that utilize tributary streams for spawning and rearing. Streams with restorable habitats were selected for improvements. Completion of improvement efforts should increase the adfluvial rainbow trout contribution to the resident fishery in Lake Roosevelt. Three co-operating agencies, the Confederated Tribes of the Colville Reservation (CCT), the Spokane Tribe of Indians (STI

NCCOS St. Croix, USVI Rapid Habitat Assessment (RHA) and Monitoring Data (2001 - Present)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This metadata record refers to habitat assessment data collected as part of a larger effort described below. The intent of this work is five fold: 1) To spatially...

Effects of Climate Change on Habitat Availability and Configuration for an Endemic Coastal Alpine Bird.

Directory of Open Access Journals (Sweden)

Michelle M Jackson

Full Text Available North America's coastal mountains are particularly vulnerable to climate change, yet harbour a number of endemic species. With little room "at the top" to track shifting climate envelopes, alpine species may be especially negatively affected by climate-induced habitat fragmentation. We ask how climate change will affect the total amount, mean patch size, and number of patches of suitable habitat for Vancouver Island White-tailed Ptarmigan (Lagopus leucura saxatilis; VIWTP, a threatened, endemic alpine bird. Using a Random Forest model and a unique dataset consisting of citizen science observations combined with field surveys, we predict the distribution and configuration of potential suitable summer habitat for VIWTP under baseline and future (2020s, 2050s, and 2080s climates using three general circulation models and two greenhouse gas scenarios. VIWTP summer habitat is predicted to decline by an average of 25%, 44%, and 56% by the 2020s, 2050s, and 2080s, respectively, under the low greenhouse gas scenario and 27%, 59%, and 74% under the high scenario. Habitat patches are predicted to become fragmented, with a 52-79% reduction in mean patch size. The average elevation of suitable habitat patches is expected to increase, reflecting a loss of patches at lower elevations. Thus ptarmigan are in danger of being "squeezed off the mountain", as their remaining suitable habitat will be increasingly confined to mountaintops in the center of the island. The extent to which ptarmigan will be able to persist in increasingly fragmented habitat is unclear. Much will depend on their ability to move throughout a more heterogeneous landscape, utilize smaller breeding areas, and survive increasingly variable climate extremes. Our results emphasize the importance of continued monitoring and protection for high elevation specialist species, and suggest that White-tailed Ptarmigan should be considered an indicator species for alpine ecosystems in the face of

Ellenberg's indicator values support prediction of suitable habitat for pre-diapause larvae of endangered butterfly Euphydryas aurinia.

Directory of Open Access Journals (Sweden)

Remigiusz Pielech

Full Text Available In spite of the great popularity of Ellenberg's Indicator Values (EIVs in plant ecology, animal ecologists seldom use EIVs to address ecological questions. In this study we used EIVs to test their potential usefulness for the prediction of suitable habitat for pre-diapause larvae of the endangered butterfly species Euphydryas aurinia. Nine transects crossing grasslands in SW Poland with abundant populations of E. aurinia were designed. We sampled 76 vegetation plots along the transects. In addition, the presence of the larval webs of E. aurinia in sampled plots was also recorded. We then calculated the mean community EIVs of light, nitrogen, soil reaction, moisture and temperature for each sample plots. Generalized linear mixed-effects models (GLMMs were used to assess which factors determine the local occurrence of larval webs of E. aurinia. We found the larval webs only in 12 plots, while the host plant was present in 39 of the examined plots. The presence of the host plant was the most important predictor in both models including all plots or including only plots with host plants. The other significant predictor was the mean EIV of light, and its importance increased in models considering all plots. We attributed the importance of the EIV of light to the site openness and density of the vegetation layer. A positive relationship between this predictor and the presence of larval webs indicates that sites with looser vegetation, a lower contribution of shrubs and tall herbs and better penetration of photosynthetically active radiation to lower vegetation layers are preferred by E. aurinia for oviposition. Moreover, the significance of EIV of light may be linked with management practices. Many light-demanding species decline after cessation of mowing as a result of litter accumulation and the dominance of tall herbs. An absence of light-demanding species decreases the community's mean EIV of light and thus indicates the influence of meadow

Towards a resource-based habitat approach for spatial modelling of vector-borne disease risks.

Science.gov (United States)

Hartemink, Nienke; Vanwambeke, Sophie O; Purse, Bethan V; Gilbert, Marius; Van Dyck, Hans

2015-11-01

Given the veterinary and public health impact of vector-borne diseases, there is a clear need to assess the suitability of landscapes for the emergence and spread of these diseases. Current approaches for predicting disease risks neglect key features of the landscape as components of the functional habitat of vectors or hosts, and hence of the pathogen. Empirical-statistical methods do not explicitly incorporate biological mechanisms, whereas current mechanistic models are rarely spatially explicit; both methods ignore the way animals use the landscape (i.e. movement ecology). We argue that applying a functional concept for habitat, i.e. the resource-based habitat concept (RBHC), can solve these issues. The RBHC offers a framework to identify systematically the different ecological resources that are necessary for the completion of the transmission cycle and to relate these resources to (combinations of) landscape features and other environmental factors. The potential of the RBHC as a framework for identifying suitable habitats for vector-borne pathogens is explored and illustrated with the case of bluetongue virus, a midge-transmitted virus affecting ruminants. The concept facilitates the study of functional habitats of the interacting species (vectors as well as hosts) and provides new insight into spatial and temporal variation in transmission opportunities and exposure that ultimately determine disease risks. It may help to identify knowledge gaps and control options arising from changes in the spatial configuration of key resources across the landscape. The RBHC framework may act as a bridge between existing mechanistic and statistical modelling approaches. © 2014 The Authors. Biological Reviews published by John Wiley & Sons Ltd on behalf of Cambridge Philosophical Society.

Evaluating Presence Data versus Expert Opinions to Assess Occurrence, Habitat Preferences and Landscape Permeability: A Case Study of Butterflies

Directory of Open Access Journals (Sweden)

Muhammad Arfan

2018-02-01

Full Text Available We explored how presence data and expert opinions performed with respect to identifying the ecological preferences and the spatial needs of six butterfly species in the Federal State of Saxony, Germany. We used presence records and a land-cover map. In parallel we used expert responses to evaluate the 40 land-cover types occurring in the map, in terms of both suitability and permeability for the six species. Presence data were translated into preferences through Ivlev’s electivity indices (IEI. Visual analysis of preference maps based on IEI showed a distinct pattern of suitable versus less suitable areas. Similarly, spatial analyses found that presence-points were closer to suitability areas based on IEI than those that were based on expert data. However, in case of mismatches between expert and presence-based evaluations, independent experts identified the expert evaluation as better and considered IEI outcomes as wrong. We found a medium to high correlation between land-cover class suitability and permeability based on expert opinions for all species. This indicates that expert evaluation of permeability is affiliated with habitat suitability. Integration of species-presence data and expert-knowledge about species could enhance our capabilities to understand and potentially map suitability while gathering information about suitability and permeability separately can improve species conservation planning.

Modeling habitat connectivity to inform reintroductions: a case study with the Chiricahua Leopard Frog

Science.gov (United States)

Jarchow, Christopher J.; Hossack, Blake R.; Sigafus, Brent H.; Schwalbe, Cecil R.; Muths, Erin L.

2016-01-01

Managing species with intensive tools such as reintroduction may focus on single sites or entire landscapes. For vagile species, long-term persistence will require colonization and establishment in neighboring habitats. Therefore, both suitable colonization sites and suitable dispersal corridors between sites are required. Assessment of landscapes for both requirements can contribute to ranking and selection of reintroduction areas, thereby improving management success. Following eradication of invasive American Bullfrogs (Lithobates catesbeianus) from most of Buenos Aires National Wildlife Refuge (BANWR; Arizona, United States), larval Chiricahua Leopard Frogs (Lithobates chiricahuensis) from a private pond were reintroduced into three stock ponds. Populations became established at all three reintroduction sites followed by colonization of neighboring ponds in subsequent years. Our aim was to better understand colonization patterns by the federally threatened L. chiricahuensis which could help inform other reintroduction efforts. We assessed the influence of four landscape features on colonization. Using surveys from 2007 and information about the landscape, we developed a habitat connectivity model, based on electrical circuit theory, that identified potential dispersal corridors after explicitly accounting for imperfect detection of frogs. Landscape features provided little insight into why some sites were colonized and others were not, results that are likely because of the uniformity of the BANWR landscape. While corridor modeling may be effective in more-complex landscapes, our results suggest focusing on local habitat will be more useful at BANWR. We also illustrate that existing data, even when limited in spatial or temporal resolution, can provide information useful in formulating management actions.

Development of computational fluid dynamics--habitat suitability (CFD-HSI) models to identify potential passage--Challenge zones for migratory fishes in the Penobscot River

Science.gov (United States)

Haro, Alexander J.; Dudley, Robert W.; Chelminski, Michael

2012-01-01

A two-dimensional computational fluid dynamics-habitat suitability (CFD–HSI) model was developed to identify potential zones of shallow depth and high water velocity that may present passage challenges for five anadromous fish species in the Penobscot River, Maine, upstream from two existing dams and as a result of the proposed future removal of the dams. Potential depth-challenge zones were predicted for larger species at the lowest flow modeled in the dam-removal scenario. Increasing flows under both scenarios increased the number and size of potential velocity-challenge zones, especially for smaller species. This application of the two-dimensional CFD–HSI model demonstrated its capabilities to estimate the potential effects of flow and hydraulic alteration on the passage of migratory fish.

A habitat overlap analysis derived from maxent for tamarisk and the south-western willow flycatcher

Science.gov (United States)

York, Patricia; Evangelista, Paul; Kumar, Sunil; Graham, James; Flather, Curtis; Stohlgren, Thomas

2011-06-01

Biologic control of the introduced and invasive, woody plant tamarisk ( Tamarix spp, saltcedar) in south-western states is controversial because it affects habitat of the federally endangered South-western Willow Flycatcher ( Empidonax traillii extimus). These songbirds sometimes nest in tamarisk where floodplain-level invasion replaces native habitats. Biologic control, with the saltcedar leaf beetle ( Diorhabda elongate), began along the Virgin River, Utah, in 2006, enhancing the need for comprehensive understanding of the tamarisk-flycatcher relationship. We used maximum entropy (Maxent) modeling to separately quantify the current extent of dense tamarisk habitat (>50% cover) and the potential extent of habitat available for E. traillii extimus within the studied watersheds. We used transformations of 2008 Landsat Thematic Mapper images and a digital elevation model as environmental input variables. Maxent models performed well for the flycatcher and tamarisk with Area Under the ROC Curve (AUC) values of 0.960 and 0.982, respectively. Classification of thresholds and comparison of the two Maxent outputs indicated moderate spatial overlap between predicted suitable habitat for E. traillii extimus and predicted locations with dense tamarisk stands, where flycatcher habitat will potentially change flycatcher habitats. Dense tamarisk habitat comprised 500 km2 within the study area, of which 11.4% was also modeled as potential habitat for E. traillii extimus. Potential habitat modeled for the flycatcher constituted 190 km2, of which 30.7% also contained dense tamarisk habitat. Results showed that both native vegetation and dense tamarisk habitats exist in the study area and that most tamarisk infestations do not contain characteristics that satisfy the habitat requirements of E. traillii extimus. Based on this study, effective biologic control of Tamarix spp. may, in the short term, reduce suitable habitat available to E. traillii extimus, but also has the potential

Chinook salmon use of spawning patches: relative roles of habitat quality, size, and connectivity.

Science.gov (United States)

Isaak, Daniel J; Thurow, Russell F; Rieman, Bruce E; Dunham, Jason B

2007-03-01

Declines in many native fish populations have led to reassessments of management goals and shifted priorities from consumptive uses to species preservation. As management has shifted, relevant environmental characteristics have evolved from traditional metrics that described local habitat quality to characterizations of habitat size and connectivity. Despite the implications this shift has for how habitats may be prioritized for conservation, it has been rare to assess the relative importance of these habitat components. We used an information-theoretic approach to select the best models from sets of logistic regressions that linked habitat quality, size, and connectivity to the occurrence of chinook salmon (Oncorhynchus tshawytscha) nests. Spawning distributions were censused annually from 1995 to 2004, and data were complemented with field measurements that described habitat quality in 43 suitable spawning patches across a stream network that drained 1150 km2 in central Idaho. Results indicated that the most plausible models were dominated by measures of habitat size and connectivity, whereas habitat quality was of minor importance. Connectivity was the strongest predictor of nest occurrence, but connectivity interacted with habitat size, which became relatively more important when populations were reduced. Comparison of observed nest distributions to null model predictions confirmed that the habitat size association was driven by a biological mechanism when populations were small, but this association may have been an area-related sampling artifact at higher abundances. The implications for habitat management are that the size and connectivity of existing habitat networks should be maintained whenever possible. In situations where habitat restoration is occurring, expansion of existing areas or creation of new habitats in key areas that increase connectivity may be beneficial. Information about habitat size and connectivity also could be used to strategically

Surface Habitat Systems

Science.gov (United States)

Kennedy, Kriss J.

2009-01-01

The Surface Habitat Systems (SHS) Focused Investment Group (FIG) is part of the National Aeronautics and Space Administration (NASA) Johnson Space Center (JSC) effort to provide a focused direction and funding to the various projects that are working on human surface habitat designs and technologies for the planetary exploration missions. The overall SHS-FIG effort focuses on directing and guiding those projects that: 1) develop and demonstrate new surface habitat system concepts, innovations, and technologies to support human exploration missions, 2) improve environmental systems that interact with human habitats, 3) handle and emplace human surface habitats, and 4) focus on supporting humans living and working in habitats on planetary surfaces. The activity areas of the SHS FIG described herein are focused on the surface habitat project near-term objectives as described in this document. The SHS-FIG effort focuses on mitigating surface habitat risks (as identified by the Lunar Surface Systems Project Office (LSSPO) Surface Habitat Element Team; and concentrates on developing surface habitat technologies as identified in the FY08 gap analysis. The surface habitat gap assessment will be updated annually as the surface architecture and surface habitat definition continues to mature. These technologies are mapped to the SHS-FIG Strategic Development Roadmap. The Roadmap will bring to light the areas where additional innovative efforts are needed to support the development of habitat concepts and designs and the development of new technologies to support of the LSSPO Habitation Element development plan. Three specific areas of development that address Lunar Architecture Team (LAT)-2 and Constellation Architecture Team (CxAT) Lunar habitat design issues or risks will be focused on by the SHS-FIG. The SHS-FIG will establish four areas of development that will help the projects prepare in their planning for surface habitat systems development. Those development areas are

Population trends, bend use relative to available habitat and within-river-bend habitat use of eight indicator species of Missouri and Lower Kansas River benthic fishes: 15 years after baseline assessment

Science.gov (United States)

Wildhaber, Mark L.; Yang, Wen-Hsi; Arab, Ali

2016-01-01

A baseline assessment of the Missouri River fish community and species-specific habitat use patterns conducted from 1996 to 1998 provided the first comprehensive analysis of Missouri River benthic fish population trends and habitat use in the Missouri and Lower Yellowstone rivers, exclusive of reservoirs, and provided the foundation for the present Pallid Sturgeon Population Assessment Program (PSPAP). Data used in such studies are frequently zero inflated. To address this issue, the zero-inflated Poisson (ZIP) model was applied. This follow-up study is based on PSPAP data collected up to 15 years later along with new understanding of how habitat characteristics among and within bends affect habitat use of fish species targeted by PSPAP, including pallid sturgeon. This work demonstrated that a large-scale, large-river, PSPAP-type monitoring program can be an effective tool for assessing population trends and habitat usage of large-river fish species. Using multiple gears, PSPAP was effective in monitoring shovelnose and pallid sturgeons, sicklefin, shoal and sturgeon chubs, sand shiner, blue sucker and sauger. For all species, the relationship between environmental variables and relative abundance differed, somewhat, among river segments suggesting the importance of the overall conditions of Upper and Middle Missouri River and Lower Missouri and Kansas rivers on the habitat usage patterns exhibited. Shoal and sicklefin chubs exhibited many similar habitat usage patterns; blue sucker and shovelnose sturgeon also shared similar responses. For pallid sturgeon, the primary focus of PSPAP, relative abundance tended to increase in Upper and Middle Missouri River paralleling stocking efforts, whereas no evidence of an increasing relative abundance was found in the Lower Missouri River despite stocking.

Habitats and Species Covered by the EEC Habitats Directive

DEFF Research Database (Denmark)

Pihl, S.; Søgaard, B.; Ejrnæs, R.

of Conservation (SAC's), Natura 2000. The designations are based upon the presence of 60 of the natural habitat types listed in Annex I of the Directive and approx. 44 of the species listed in Annex II which occur within the territory of Denmark and for the conservation of which the Community has a special...... and the Danish county authorities have initiated a co-operative programme to provide and compile the data necessary to assess the conservation status of the natural habitat types and species concerned. The purpose of this report is to present the conservation status of the habitats and species in Denmark...

Multi–criteria evaluation and simulated annealing for delimiting high priority habitats of Alectoris chukar and Phasianus colchicus in Iran

Directory of Open Access Journals (Sweden)

Momeni Dehaghi, I.

2018-01-01

Full Text Available Habitat degradation and hunting are among the most important causes of population decline for Alectoris chukar and Phasianus colchicus, two of the most threatened game species in the Golestan Province of Iran. Limited data on distribution and location of high–quality habitats for the two species make conservation efforts more difficult in the province. We used multi–criteria evaluation (MCE as a coarse–filter approach to refine the general distribution areas into habitat suitability maps for the species. We then used these maps as input to simulated annealing as a heuristic algorithm through Marxan in order to prioritize areas for conservation of the two species. To find the optimal solution, we tested various boundary length modifier (BLM values in the simulated annealing process. Our results showed that the MCE approach was useful to refine general habitat maps. Assessment of the selected reserves confirmed the suitability of the selected areas (mainly neighboring the current reserves making their management easier and more feasible. The total area of the selected reserves was about 476 km2. As current reserves of the Golestan Province represent only 23 % of the optimal area, further protected areas should be considered to efficiently conserve these two species.

Projected future suitable habitat and productivity of Douglas-fir in western North America

Science.gov (United States)

Aaron R. Weiskittel; Nicholas L. Crookston; Gerald E. Rehfeldt

2012-01-01

Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) is one of the most common and commercially important species in western North America. The species can occupy a range of habitats, is long-lived (up to 500 years), and highly productive. However, the future of Douglas-fir in western North America is highly uncertain due to the expected changes in climate conditions....

Implications of Fine-Grained Habitat Fragmentation and Road Mortality for Jaguar Conservation in the Atlantic Forest, Brazil.

Directory of Open Access Journals (Sweden)

Laury Cullen

Full Text Available Jaguar (Panthera onca populations in the Upper Paraná River, in the Brazilian Atlantic Forest region, live in a landscape that includes highly fragmented areas as well as relatively intact ones. We developed a model of jaguar habitat suitability in this region, and based on this habitat model, we developed a spatially structured metapopulation model of the jaguar populations in this area to analyze their viability, the potential impact of road mortality on the populations' persistence, and the interaction between road mortality and habitat fragmentation. In more highly fragmented populations, density of jaguars per unit area is lower and density of roads per jaguar is higher. The populations with the most fragmented habitat were predicted to have much lower persistence in the next 100 years when the model included no dispersal, indicating that the persistence of these populations are dependent to a large extent on dispersal from other populations. This, in turn, indicates that the interaction between road mortality and habitat fragmentation may lead to source-sink dynamics, whereby populations with highly fragmented habitat are maintained only by dispersal from populations with less fragmented habitat. This study demonstrates the utility of linking habitat and demographic models in assessing impacts on species living in fragmented landscapes.

Implications of Fine-Grained Habitat Fragmentation and Road Mortality for Jaguar Conservation in the Atlantic Forest, Brazil.

Science.gov (United States)

Cullen, Laury; Stanton, Jessica C; Lima, Fernando; Uezu, Alexandre; Perilli, Miriam L L; Akçakaya, H Reşit

2016-01-01

Jaguar (Panthera onca) populations in the Upper Paraná River, in the Brazilian Atlantic Forest region, live in a landscape that includes highly fragmented areas as well as relatively intact ones. We developed a model of jaguar habitat suitability in this region, and based on this habitat model, we developed a spatially structured metapopulation model of the jaguar populations in this area to analyze their viability, the potential impact of road mortality on the populations' persistence, and the interaction between road mortality and habitat fragmentation. In more highly fragmented populations, density of jaguars per unit area is lower and density of roads per jaguar is higher. The populations with the most fragmented habitat were predicted to have much lower persistence in the next 100 years when the model included no dispersal, indicating that the persistence of these populations are dependent to a large extent on dispersal from other populations. This, in turn, indicates that the interaction between road mortality and habitat fragmentation may lead to source-sink dynamics, whereby populations with highly fragmented habitat are maintained only by dispersal from populations with less fragmented habitat. This study demonstrates the utility of linking habitat and demographic models in assessing impacts on species living in fragmented landscapes.

Habitat evaluation of wild Amur tiger (Panthera tigris altaica) and conservation priority setting in north-eastern China.

Science.gov (United States)

Xiaofeng, Luan; Yi, Qu; Diqiang, Li; Shirong, Liu; Xiulei, Wang; Bo, Wu; Chunquan, Zhu

2011-01-01

The Amur Tiger (Panthera tigris altaica) is one of the world's most endangered species. Recently, habitat fragmentation, food scarcity and human hunting have drastically reduced the population size and distribution areas of Amur tigers in the wild, leaving them on the verge of extinction. Presently, they are only found in the north-eastern part of China. In this study, we developed a reference framework using methods and technologies of analytic hierarchy process (AHP), remote sensing (RS), geographic information system (GIS), GAP analysis and Natural Break (Jenks) classification to evaluate the habitat and to set the conservation priorities for Amur tigers in eastern areas of Heilongjiang and Jilin Provinces of northeast China. We proposed a Habitat Suitability Index (HSI) incorporating 7 factors covering natural conditions and human disturbance. Based on the HSI values, the suitability was classified into five levels from the most to not suitable. Finally, according to results of GAP analysis, we identified six conservation priorities and designed a conservation landscape incorporating four new nature reserves, enlarging two existing ones, and creating four linkages for Amur tigers in northeast China. The case study showed that the core habitats (the most suitable and highly suitable habitats) identified for Amur tigers covered 35,547 km(2), accounting for approximately 26.71% of the total study area (1,33,093 km(2)). However, existing nature reserves protected only (7124 km(2) or) 20.04% of the identified core habitats. Thus, enlargement of current reserves is necessary and urgent for the tiger's conservation and restoration. Moreover, the establishment of wildlife corridors linking core habitats will provide an efficient reserve network for tiger conservation to maintain the evolutionary potential of Amur tigers facing environmental changes. Copyright © 2010 Elsevier Ltd. All rights reserved.

Production of fiberglass/metal composite material suitable for building habitat and manufacturing facilities

Science.gov (United States)

1987-01-01

The production of a fiberglass/metal composite material suitable for building habitats and manufacturing facilities was the project for Clemson. The concept and development of the knowledge necessary to produce glass fibers originated in the spring semester. During the summer, while at Johnson Space Center, fiberglass from a rock composition similar to ones found at the Apollo 16 site on the moon was successfully produced. The project this year was a continuation of last year's studies. We addressed the following problems which emerged as the work progressed: (1) Methods for coating the fibers with a metal were explored. We manufactured composites in two stages: Glass fibers without any coating on them; and fibers coated with metals as they were made. This proved to be a difficult process. Future activities include using a chemical vapor deposition process on fibers which have been made. (2) A glass furnace was developed which relies primarily on solar energy for melting the glass. The temperature of the melted glass is maintained by electrical means. The design is for 250 kg of glass per day. An electrical engineering student developed a scheme for controlling the melting and manufacturing process from the earth. This was done to minimize the human risk. Graphite refractories are relied on to contain the melt. (3) The glass composition chosen for the project is a relatively pure anorthite which is available in the highland regions of the lunar surface. A major problems with this material is that it melts at a comparatively high temperature. This problem will be solved by using graphite refractory materials for the furnace. The advantage of this glass composition is that it is very stable and does not tend to crystallize. (4) We have also refined the experimental furnace and fiber making machinery which we will be using at Johnson Space Center this summer. We believe that we will be able to draw and coat glass fibers in a vacuum for use in composites. We intend to

Modelling climate change impacts on stream habitat conditions

DEFF Research Database (Denmark)

Boegh, Eva; Conallin, John; Karthikeyan, Matheswaran

Impact from groundwater abstraction on freshwater resources and ecosystems is an issue of sincere concern in Denmark and many other countries worldwide. In addition, climate change projections add complexity to the existing conflict between water demands to satisfy human needs and water demands...... required to conserve streams as biologically diverse and healthy ecosystems. Solutions to this intensifying conflict require a holistic approach whereby stream biota is related to their physical environment at catchment scale, as also demanded by the EU Water Framework Directive. In the present study......, climate impacts on stream ecological conditions were quantified by combining a heat and mass stream flow with a habitat suitability modelling approach. Habitat suitability indices were developed for stream velocity, water depth, water temperature and substrate. Generally, water depth was found...

The use of computer simulation to assess the suitability of RWH ...

African Journals Online (AJOL)

... which was designed to assess the suitability of RWH technology interventions for any new site. The simulation model is briefly described and typical examples of its use as a tool for agro-technology transfer are presented. The interface is user-friendly and the model itself is designed to work with readily available site data.

Testing Cort-Fitness and Cort-Adaptation hypotheses in a habitat suitability gradient for roe deer

Science.gov (United States)

Escribano-Avila, Gema; Pettorelli, Nathalie; Virgós, Emilio; Lara-Romero, Carlos; Lozano, Jorge; Barja, Isabel; Cuadra, Felipe S.; Puerta, Marisa

2013-11-01

According to the Cort-Fitness Hypothesis, higher stress levels (glucocorticoids) in vertebrates are correlated to lower fitness. However, recent studies have failed to validate this hypothesis. A proposed wider framework suggests that reproduction can be perceived as an overload adds up to other environmental challenges that individuals must adjust to. In this case, elevated glucocorticoids could help individuals to allocate resources to reproduction without comprising other functions, leading to the expectation of a positive cort-fitness relationship. This has been proposed as the Cort-Adaptation Hypothesis. Stress levels result from a complex interaction between the environment and the neuroendocrine system of animals. Accounting for physiological functions involved in how animals cope with their environment would help to clarify the relationship between glucocorticoids and animal performance. We used roe deer (Capreolus capreolus) inhabiting diverse habitats in the Iberian Peninsula to: i) test the Cort-Fitness and Cort-Adaptation hypotheses by indexing fitness using a comprehensive physiological approach which takes into account fundamental physiological functions and their trade-offs; and ii) evaluate the link between primary productivity and individuals' condition in a seasonal environment. We evaluated spatial and temporal variation in stress levels, reproductive hormone levels, nutritional status and immune function from fecal samples collected in 2010. Lower stress levels were related to better condition in non-reproductive seasons but not to higher primary productivity. In contrast, stress levels were always positively related to reproductive condition, which was better in most productive habitats. Summer and winter were the less productive seasons and the more challenging for the species in the habitat gradient studied. In winter, reproductive condition traded off against immune function being biased toward immune function in less productive habitats. In

Effects of natural-channel-design restoration on habitat quality in Catskill Mountain streams, New York

Science.gov (United States)

Ernst, Anne G.; Baldigo, Barry P.; Mulvihill, Christiane; Vian, Mark

2010-01-01

Stream restoration has received much attention in recent years, yet there has been little effort to evaluate its impacts on physical habitat, stability, and biota. A popular but controversial stream restoration approach is natural channel design (NCD), which cannot be adequately evaluated without a long-term, independent assessment of its effects on stream habitat. Six reaches of five Catskill Mountain streams in southeastern New York were restored during 2000–2003 following NCD techniques to decrease bed and bank degradation, decrease sediment loads, and improve water quality. Habitat surveys were conducted during summer low flows from 2001 to 2007. The effects of the NCD projects on stream condition were assessed via a before–after–control–impact study design to quantify the net changes in stream and bank habitat variables relative to those in unaltered control reaches. Analysis of variance tests of three different measures of bank stability show that on average stream stability increased at treatment sites for 2–5 years after restoration. Mean channel depth, thalweg depth, and the pool–riffle ratio generally increased, whereas mean channel width, percent streambank coverage by trees, and shade decreased. Habitat suitability indices for local salmonid species increased at four of six reaches after restoration. The changes in channel dimensions rendered them generally more characteristic of stabler stream forms in the given valley settings. Although these studies were done relatively soon after project completion, our findings demonstrate that habitat conditions can be improved in degraded Catskill Mountain streams through NCD restoration.

Land Use Suitability Assessment in Low-Slope Hilly Regions under the Impact of Urbanization in Yunnan, China

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Gui Jin

2015-01-01

Full Text Available Nowadays, the conflict between land development and land conservation has become increasingly serious in China. The plan called “town of mountain” is carried out in many nonplain areas to alleviate the conflict. To avoid geological disasters and ecological risks in those areas, land use suitability assessment is of great importance. In this paper, the fuzzy weight of evidence model is applied into land use suitability assessment in low-slope hilly regions in Yunnan, China. Fuzzy weight of evidences is calculated to determine 9 map layers. Finally, posterior probabilities are modified after synthesizing each map layer, which are used to generate a land use suitability map. The results show that 9.33%, 26.18%, 45.98%, and 18.51% of low-slope hilly regions are separately highly suitable, moderately suitable, marginally suitable, and unsuitable for development. Besides, highly and moderately suitable areas are mainly located in towns with excellent natural and socioeconomic conditions. The largest areas which are marginally suitable for development are most widely distributed. Unsuitable areas are mainly distributed far away from towns and water sources. The findings of the research will promote the rational use and scientific management of the land.

Rainwater Wildlife Area Habitat Evaluation Procedures Report; A Columbia Basin Wildlife Mitigation Project.

Energy Technology Data Exchange (ETDEWEB)

Childs, Allen B.

2004-01-01

The 8,768 acre Rainwater Wildlife Area was acquired in September 1998 by the Confederated Tribes of the Umatilla Indian Reservation (CTUIR) through an agreement with Bonneville Power Administration (BPA) to partially offset habitat losses associated with construction of the John Day and McNary hydroelectric facilities on the mainstem Columbia River. U.S. Fish and Wildlife Service (USFWS) Habitat Evaluation Procedures (HEP) were used to determine the number of habitat units credited to BPA for acquired lands. Upland and riparian forest, upland and riparian shrub, and grassland cover types are evaluated in this study. Targeted wildlife species include downy woodpecker (Picoides pubescens), black-capped chickadee (Parus atricopillus), blue grouse (Dendragapus obscurus), great blue heron (Ardea herodias), yellow warbler (Dendroica petechia), mink (Mustela vison), and Western meadowlark (Sturnella neglecta). Habitat surveys were conducted in 1998 and 1999 in accordance with published HEP protocols and included 65,300, 594m{sup 2}2 plots, and 112 one-tenth-acre plots. Between 153.3 and 7,187.46 acres were evaluated for each target wildlife mitigation species. Derived habitat suitability indices were multiplied by corresponding cover-type acreages to determine the number of habitat units for each species. The total baseline habitat units credited to BPA for the Rainwater Wildlife Area and its seven target species is 5,185.3 habitat units. Factors limiting habitat suitability are related to the direct, indirect, and cumulative effects of past livestock grazing, road construction, and timber harvest which have simplified the structure, composition, and diversity of native plant communities. Alternatives for protecting and improving habitat suitability include exclusion of livestock grazing, road de-commissioning/obliteration, reforestation and thinning, control of competing and unwanted vegetation (including noxious weeds), reestablishing displaced or reduced native

Potential impacts of climate change on flow regime and fish habitat in mountain rivers of the south-western Balkans.

Science.gov (United States)

Papadaki, Christina; Soulis, Konstantinos; Muñoz-Mas, Rafael; Martinez-Capel, Francisco; Zogaris, Stamatis; Ntoanidis, Lazaros; Dimitriou, Elias

2016-01-01

The climate change in the Mediterranean area is expected to have significant impacts on the aquatic ecosystems and particular in the mountain rivers and streams that often host important species such as the Salmo farioides, Karaman 1938. These impacts will most possibly affect the habitat availability for various aquatic species resulting to an essential alteration of the water requirements, either for dams or other water abstractions, in order to maintain the essential levels of ecological flow for the rivers. The main scope of this study was to assess potential climate change impacts on the hydrological patterns and typical biota for a south-western Balkan mountain river, the Acheloos. The altered flow regimes under different emission scenarios of the Intergovernmental Panel on Climate Change (IPCC) were estimated using a hydrological model and based on regional climate simulations over the study area. The Indicators of Hydrologic Alteration (IHA) methodology was then used to assess the potential streamflow alterations in the studied river due to predicted climate change conditions. A fish habitat simulation method integrating univariate habitat suitability curves and hydraulic modeling techniques were used to assess the impacts on the relationships between the aquatic biota and hydrological status utilizing a sentinel species, the West Balkan trout. The most prominent effects of the climate change scenarios depict severe flow reductions that are likely to occur especially during the summer flows, changing the duration and depressing the magnitude of the natural low flow conditions. Weighted Usable Area-flow curves indicated the limitation of suitable habitat for the native trout. Finally, this preliminary application highlighted the potential of science-based hydrological and habitat simulation approaches that are relevant to both biological quality elements (fish) and current EU Water policy to serve as efficient tools for the estimation of possible climate

Tamarix as habitat for birds: Implications for riparian restoration in the Southwestern United States

Science.gov (United States)

Sogge, M.K.; Sferra, S.J.; Paxton, E.H.

2008-01-01

Exotic vegetation has become a major habitat component in many ecosystems around the world, sometimes dramatically changing the vegetation community structure and composition. In the southwestern United States, riparian ecosystems are undergoing major changes in part due to the establishment and spread of the exotic Tamarix (saltcedar, tamarisk). There are concerns about the suitability of Tamarix as habitat for birds. Although Tamarix habitats tend to support fewer species and individuals than native habitats, Arizona Breeding Bird Atlas data and Birds of North America accounts show that 49 species use Tamarix as breeding habitat. Importantly, the relative use of Tamarix and its quality as habitat vary substantially by geographic location and bird species. Few studies have examined how breeding in Tamarix actually affects bird survivorship and productivity; recent research on Southwestern Willow Flycatchers has found no negative effects from breeding in Tamarix habitats. Therefore, the ecological benefits and costs of Tamarix control are difficult to predict and are likely to be species specific and site specific. Given the likelihood that high-quality native riparian vegetation will not develop at all Tamarix control sites, restoration projects that remove Tamarix but do not assure replacement by high-quality native habitat have the potential to reduce the net riparian habitat value for some local or regional bird populations. Therefore, an assessment of potential negative impacts is important in deciding if exotic control should be conducted. In addition, measurable project objectives, appropriate control and restoration techniques, and robust monitoring are all critical to effective restoration planning and execution. ?? 2008 Society for Ecological Restoration International.

Guidance for Large-scale Implementation of Alternate Wetting and Drying: A Biophysical Suitability Assessment

Science.gov (United States)

Sander, B. O.; Wassmann, R.; Nelson, A.; Palao, L.; Wollenberg, E.; Ishitani, M.

2014-12-01

The alternate wetting and drying (AWD) technology for rice production does not only save 15-30% of irrigation water, it also reduces methane emissions by up to 70%. AWD is defined by periodic drying and re-flooding of a rice field. Due to its high mitigation potential and its simplicity to execute this practice AWD has gained a lot of attention in recent years. The Climate and Clean Air Coalition (CCAC) has put AWD high on its agenda and funds a project to guide implementation of this technology in Vietnam, Bangladesh and Colombia. One crucial activity is a biophysical suitability assessment for AWD in the three countries. For this, we analyzed rainfall and soil data as well as potential evapotranspiration to assess if the water balance allows practicing AWD or if precipitation is too high for rice fields to fall dry. In my talk I will outline key factors for a successful large-scale implementation of AWD with a focus on the biophysical suitability assessment. The seasonal suitability maps that we generated highlight priority areas for AWD implementation and guide policy makers to informed decisions about meaningful investments in infrastructure and extension work.

Smartphone technologies and Bayesian networks to assess shorebird habitat selection

Science.gov (United States)

Zeigler, Sara; Thieler, E. Robert; Gutierrez, Ben; Plant, Nathaniel G.; Hines, Megan K.; Fraser, James D.; Catlin, Daniel H.; Karpanty, Sarah M.

2017-01-01

Understanding patterns of habitat selection across a species’ geographic distribution can be critical for adequately managing populations and planning for habitat loss and related threats. However, studies of habitat selection can be time consuming and expensive over broad spatial scales, and a lack of standardized monitoring targets or methods can impede the generalization of site-based studies. Our objective was to collaborate with natural resource managers to define available nesting habitat for piping plovers (Charadrius melodus) throughout their U.S. Atlantic coast distribution from Maine to North Carolina, with a goal of providing science that could inform habitat management in response to sea-level rise. We characterized a data collection and analysis approach as being effective if it provided low-cost collection of standardized habitat-selection data across the species’ breeding range within 1–2 nesting seasons and accurate nesting location predictions. In the method developed, >30 managers and conservation practitioners from government agencies and private organizations used a smartphone application, “iPlover,” to collect data on landcover characteristics at piping plover nest locations and random points on 83 beaches and barrier islands in 2014 and 2015. We analyzed these data with a Bayesian network that predicted the probability a specific combination of landcover variables would be associated with a nesting site. Although we focused on a shorebird, our approach can be modified for other taxa. Results showed that the Bayesian network performed well in predicting habitat availability and confirmed predicted habitat preferences across the Atlantic coast breeding range of the piping plover. We used the Bayesian network to map areas with a high probability of containing nesting habitat on the Rockaway Peninsula in New York, USA, as an example application. Our approach facilitated the collation of evidence-based information on habitat selection

Integrating Open Access Geospatial Data to Map the Habitat Suitability of the Declining Corn Bunting (Miliaria calandra

Directory of Open Access Journals (Sweden)

Abdulhakim M. Abdi

2013-09-01

Full Text Available The efficacy of integrating open access geospatial data to produce habitat suitability maps for the corn bunting (Miliaria calandra was investigated. Landsat Enhanced Thematic Mapper Plus (ETM+, Shuttle Radar Topography Mission (SRTM and Corine (Coordination of Information on the Environment land cover data for the year 2000 (CLC2000 were processed to extract explanatory variables and divided into three sets; Satellite (ETM+, SRTM, CLC2000 and Combined (CLC2000 + Satellite. Presence-absence data for M. calandra, collected during structured surveys for the Catalan Breeding Bird Atlas, were provided by the Catalan Ornithological Institute. The dataset was partitioned into an equal number of presence and absence points by dividing it into five groups, each composed of 88 randomly selected presence points to match the number of absences. A logistic regression model was then built for each group. Models were evaluated using area under the curve (AUC of the receiver operating characteristic (ROC. Results of the five groups were averaged to produce mean Satellite, CLC2000 and Combined models. The mean AUC values were 0.69, 0.81 and 0.90 for the CLC2000, Satellite and the Combined model, respectively. The probability of M. calandra presence had the strongest positive correlation with land surface temperature, modified soil adjusted vegetation index, coefficient of variation for ETM+ band 5 and the fraction of non-irrigated arable land.

Habitat Evaluation Procedures (HEP) Report : Rainwater Wildlife Area, 1998-2001 Technical Report.

Energy Technology Data Exchange (ETDEWEB)

Childs, Allen

2004-01-01

The 8,768 acre Rainwater Wildlife Area was acquired in September 1998 by the Confederated Tribes of the Umatilla Indian Reservation (CTUIR) through an agreement with Bonneville Power Administration (BPA) to partially offset habitat losses associated with construction of the John Day and McNary hydroelectric facilities on the mainstem Columbia River. U.S. Fish and Wildlife Service (USFWS) Habitat Evaluation Procedures (HEP) were used to determine the number of habitat units credited to BPA for acquired lands. Upland and riparian forest, upland and riparian shrub, and grassland rover types are evaluated in this study. Targeted wildlife species include downy woodpecker (Picoides pubescens), black-capped chickadee (Parus atricopillus), blue grouse (Dendragapus obscurus), great blue heron (Ardea herodias), yellow warbler (Dendroica petechia), mink (Mustela vison), and Western meadowlark (Sturnella neglects). Habitat surveys were conducted in 1998 and 1999 in accordance with published HEP protocols and included 65,300, 594m{sup 2} plots, and 112 one-tenth-acre plots. Between 153.3 and 7,187.46 acres were evaluated for each target wildlife mitigation species. Derived habitat suitability indices were multiplied by corresponding cover-type acreages to determine the number of habitat units for each species. The total baseline habitat units credited to BPA for the Rainwater Wildlife Area and its seven target species is 5,185.3 habitat units. Factors limiting habitat suitability are related to the direct, indirect, and cumulative effects of past livestock grazing, road construction, and timber harvest which have simplified the structure, composition, and diversity of native plant communities. Alternatives for protecting and improving habitat suitability include exclusion of livestock grazing, road de-commissioning/obliteration, reforestation and thinning, control of competing and unwanted vegetation (including noxious weeds), reestablishing displaced or reduced native

Modeling of Iranian Cheetah Habitat using Ecological Niche Factor Analysis (Case Study: Dare Anjir Wildlife Refuge

Directory of Open Access Journals (Sweden)

N. Zamani

2016-03-01

Full Text Available Evaluation of habitat sustainability indexes is essential in wildlife management and conservation of rare species. Suitable habitats are required in wildlife managements and conservation also, they increase reproduction and survival rate of species. In this study in order to mapping habitat sustainability and recognizing habitat requirements of Iranian Cheetah (Acinonyx jubatus venaticus, field data from Dare Anjir  wildlife refuge were collected since autumn 2009 until summer 2011. Ecological Niche Factor Analysis approach has been used to develop habitat suitability model. In this method primary maps of  habitat variables including elevation, slope, aspect, vegetation cover, distance from water sources and environmental monitoring stations have been produced by Idrisi and Biomapper software and imported in Biomapper. The output scores obtained from the analysis showed that Iranian cheetah tends to mountain areas where has more topographical features for camouflage in order to hunting, and northern aspects which have more humidity, denser vegetation cover and more preys . Our result showed that the Iranian cheetah has medium niche width and prefer marginal habitats.

Bioeffects Assessment in Kvichak and Nushagak Bay, Alaska: Characterization of Soft Bottom Benthic Habitats, Fish Body Burdens and Contaminant Baseline Assessment

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The goal of this project is to assess habitat conditions that influence biodiversity and distribution of benthic infaunal communities, contaminants, and chemical...

Habitat selection and management of the Hawaiian crow

Science.gov (United States)

Giffen, J.G.; Scott, J.M.; Mountainspring, S.

1987-01-01

The abundance and range of the Hawaiian crow, or alala, (Corvus hawaiiensis) have decreased drastically since the 1890's. Fewer than 10 breeding pairs remained in the wild in 1985. A sample of 82 nests during 1970-82 were used to determine habitat associations. Two hundred firty-nine alala observations were used to estimate densities occurring in different vegetation types in 1978. Compared to available habitat, more nests and higher bird densities during the breeding season occurred in areas where: (1) canopy cover was > 60%; (2) koa (Acacia koa) and ohia (Metrosideros polymorpha) were dominant species in the crown layer; (3) native plants constituted > 75% of the understory cover; and (4) the elevation was 1,100-1,500 m. Compared to breeding habitat, nonbreeding habitat tended to lie at lower elevations and in wetter forests having the crown layer dominated by ohia but lacking koa. Habitat loss is a major factor underlying the decline of this species although predation on fledgings, avian disease, and shooting also have reduced the population. Remaining key habitat areas have little or no legal protection through zoning and land ownership. Preserves should be established to encompass the location of existing pairs and to assure the provision of optimum breeding habitat and suitable nonbreeding habitat.

Does habitat variability really promote metabolic network modularity?

Science.gov (United States)

Takemoto, Kazuhiro

2013-01-01

The hypothesis that variability in natural habitats promotes modular organization is widely accepted for cellular networks. However, results of some data analyses and theoretical studies have begun to cast doubt on the impact of habitat variability on modularity in metabolic networks. Therefore, we re-evaluated this hypothesis using statistical data analysis and current metabolic information. We were unable to conclude that an increase in modularity was the result of habitat variability. Although horizontal gene transfer was also considered because it may contribute for survival in a variety of environments, closely related to habitat variability, and is known to be positively correlated with network modularity, such a positive correlation was not concluded in the latest version of metabolic networks. Furthermore, we demonstrated that the previously observed increase in network modularity due to habitat variability and horizontal gene transfer was probably due to a lack of available data on metabolic reactions. Instead, we determined that modularity in metabolic networks is dependent on species growth conditions. These results may not entirely discount the impact of habitat variability and horizontal gene transfer. Rather, they highlight the need for a more suitable definition of habitat variability and a more careful examination of relationships of the network modularity with horizontal gene transfer, habitats, and environments.

Assessment of Managed Aquifer Recharge Site Suitability Using a GIS and Modeling.

Science.gov (United States)

Russo, Tess A; Fisher, Andrew T; Lockwood, Brian S

2015-01-01

We completed a two-step regional analysis of a coastal groundwater basin to (1) assess regional suitability for managed aquifer recharge (MAR), and (2) quantify the relative impact of MAR activities on groundwater levels and sea water intrusion. The first step comprised an analysis of surface and subsurface hydrologic properties and conditions, using a geographic information system (GIS). Surface and subsurface data coverages were compiled, georeferenced, reclassified, and integrated (including novel approaches for combining related datasets) to derive a spatial distribution of MAR suitability values. In the second step, results from the GIS analysis were used with a regional groundwater model to assess the hydrologic impact of potential MAR placement and operating scenarios. For the region evaluated in this study, the Pajaro Valley Groundwater Basin, California, GIS results suggest that about 7% (15 km2) of the basin may be highly suitable for MAR. Modeling suggests that simulated MAR projects placed near the coast help to reduce sea water intrusion more rapidly, but these projects also result in increased groundwater flows to the ocean. In contrast, projects placed farther inland result in more long-term reduction in sea water intrusion and less groundwater flowing to the ocean. This work shows how combined GIS analysis and modeling can assist with regional water supply planning, including evaluation of options for enhancing groundwater resources. © 2014, National Ground Water Association.

Blanding’s Turtle (Emydoidea blandingii Potential Habitat Mapping Using Aerial Orthophotographic Imagery and Object Based Classification

Directory of Open Access Journals (Sweden)

Douglas J. King

2012-01-01

Full Text Available Blanding’s turtle (Emydoidea blandingii is a threatened species under Canada’s Species at Risk Act. In southern Québec, field based inventories are ongoing to determine its abundance and potential habitat. The goal of this research was to develop means for mapping of potential habitat based on primary habitat attributes that can be detected with high-resolution remotely sensed imagery. Using existing spring leaf-off 20 cm resolution aerial orthophotos of a portion of Gatineau Park where some Blanding’s turtle observations had been made, habitat attributes were mapped at two scales: (1 whole wetlands; (2 within wetland habitat features of open water, vegetation (used for camouflage and thermoregulation, and logs (used for spring sun-basking. The processing steps involved initial pixel-based classification to eliminate most areas of non-wetland, followed by object-based segmentations and classifications using a customized rule sequence to refine the wetland map and to map the within wetland habitat features. Variables used as inputs to the classifications were derived from the orthophotos and included image brightness, texture, and segmented object shape and area. Independent validation using field data and visual interpretation showed classification accuracy for all habitat attributes to be generally over 90% with a minimum of 81.5% for the producer’s accuracy of logs. The maps for each attribute were combined to produce a habitat suitability map for Blanding’s turtle. Of the 115 existing turtle observations, 92.3% were closest to a wetland of the two highest suitability classes. High-resolution imagery combined with object-based classification and habitat suitability mapping methods such as those presented provide a much more spatially explicit representation of detailed habitat attributes than can be obtained through field work alone. They can complement field efforts to document and track turtle activities and can contribute to