Microglia and neurons in the hippocampus of migratory sandpipers

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C.G. Diniz

2016-01-01

Full Text Available The semipalmated sandpiper Calidris pusilla and the spotted sandpiper Actitis macularia are long- and short-distance migrants, respectively. C. pusilla breeds in the sub-arctic and mid-arctic tundra of Canada and Alaska and winters on the north and east coasts of South America. A. macularia breeds in a broad distribution across most of North America from the treeline to the southern United States. It winters in the southern United States, and Central and South America. The autumn migration route of C. pusilla includes a non-stop flight over the Atlantic Ocean, whereas autumn route of A. macularia is largely over land. Because of this difference in their migratory paths and the visuo-spatial recognition tasks involved, we hypothesized that hippocampal volume and neuronal and glial numbers would differ between these two species. A. macularia did not differ from C. pusilla in the total number of hippocampal neurons, but the species had a larger hippocampal formation and more hippocampal microglia. It remains to be investigated whether these differences indicate interspecies differences or neural specializations associated with different strategies of orientation and navigation.

Energetic solutions of Rock Sandpipers to harsh winter conditions rely on prey quality

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Ruthrauff, Daniel R.; Dekinga, Anne; Gill, Robert E.; Piersma, Theunis

2018-01-01

Rock Sandpipers Calidris ptilocnemis have the most northerly non-breeding distribution of any shorebird in the Pacific Basin (upper Cook Inlet, Alaska; 61°N, 151°W). In terms of freezing temperatures, persistent winds and pervasive ice, this site is the harshest used by shorebirds during winter. We integrated physiological, metabolic, behavioural and environmental aspects of the non-breeding ecology of Rock Sandpipers at the northern extent of their range to determine the relative importance of these factors in facilitating their unique non-breeding ecology. Not surprisingly, estimated daily energetic demands were greatest during January, the coldest period of winter. These estimates were greatest for foraging birds, and exceeded basal metabolic rates by a factor of 6.5, a scope of increase that approaches the maximum sustained rate of energetic output by shorebirds during periods of migration, but far exceeds these periods in duration. We assessed the quality of their primary prey, the bivalve Macoma balthica, to determine the daily foraging duration required by Rock Sandpipers to satisfy such energetic demands. Based on size-specific estimates of M. balthica quality, Rock Sandpipers require over 13 h/day of foraging time in upper Cook Inlet in January, even when feeding on the highest quality prey. This range approaches the average daily duration of mudflat availability in this region (c. 18 h), a maximum value that annually decreases due to the accumulation of shore-fast ice. Rock Sandpipers are likely to maximize access to foraging sites by following the exposure of ice-free mudflats across the upper Cook Inlet region and by selecting smaller, higher quality M. balthica to minimize foraging times. Ultimately, this unusual non-breeding ecology relies on the high quality of their prey resources. Compared with other sites across their range, M. balthica from upper Cook Inlet have relatively light shells, potentially the result of the region

Identical metabolic rate and thermal conductance in Rock Sandpiper (Calidris ptilocnemis) subspecies with contrasting nonbreeding life histories

NARCIS (Netherlands)

Ruthrauff, Dan; Dekinga, Anne; Gill, Robert E.; Piersma, Theunis

Closely related species or subspecies can exhibit metabolic differences that reflect site-specific environmental conditions. Whether such differences represent fixed traits or flexible adjustments to local conditions, however, is difficult to predict across taxa. The nominate race of Rock Sandpiper

Small population size of Pribilof Rock Sandpipers confirmed through distance-sampling surveys in Alaska

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Ruthrauff, Daniel R.; Tibbitts, T. Lee; Gill, Robert E.; Dementyev, Maksim N.; Handel, Colleen M.

2012-01-01

The Rock Sandpiper (Calidris ptilocnemis) is endemic to the Bering Sea region and unique among shorebirds in the North Pacific for wintering at high latitudes. The nominate subspecies, the Pribilof Rock Sandpiper (C. p. ptilocnemis), breeds on four isolated islands in the Bering Sea and appears to spend the winter primarily in Cook Inlet, Alaska. We used a stratified systematic sampling design and line-transect method to survey the entire breeding range of this population during springs 2001-2003. Densities were up to four times higher on the uninhabited and more northerly St. Matthew and Hall islands than on St. Paul and St. George islands, which both have small human settlements and introduced reindeer herds. Differences in density, however, appeared to be more related to differences in vegetation than to anthropogenic factors, raising some concern for prospective effects of climate change. We estimated the total population at 19 832 birds (95% CI 17 853–21 930), ranking it among the smallest of North American shorebird populations. To determine the vulnerability of C. p. ptilocnemis to anthropogenic and stochastic environmental threats, future studies should focus on determining the amount of gene flow among island subpopulations, the full extent of the subspecies' winter range, and the current trajectory of this small population.

A puzzling migratory detour : Are fueling conditions in Alaska driving the movement of juvenile sharp -tailed sandpipers ?

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Lindstrom, A.; Gill, Robert E.; Jamieson, S.E.; McCaffery, B.; Wennerberg, Liv; Wikelski, M.; Klaassen, M.

2011-01-01

Making a detour can be advantageous to a migrating bird if fuel-deposition rates at stopover sites along the detour are considerably higher than at stopover sites along a more direct route. One example of an extensive migratory detour is that of the Sharp-tailed Sandpiper (Calidris acuminata), of which large numbers of juveniles are found during fall migration in western Alaska. These birds take a detour of 1500-3400 km from the most direct route between their natal range in northeastern Siberia and nonbreeding areas in Australia. We studied the autumnal fueling rates and fuel loads of 357 Sharp-tailed Sandpipers captured in western Alaska. In early September the birds increased in mass at a rate of only 0.5% of lean body mass day?1. Later in September, the rate of mass increase was about 6% of lean body mass day?1, among the highest values found among similar-sized shorebirds around the world. Some individuals more than doubled their body mass because of fuel deposition, allowing nonstop flight of between 7100 and 9800 km, presumably including a trans-oceanic flight to the southern hemisphere. Our observations indicated that predator attacks were rare in our study area, adding another potential benefit of the detour. We conclude that the most likely reason for the Alaskan detour is that it allows juvenile Sharp-tailed Sandpipers to put on large fuel stores at exceptionally high rates. Copyright ?? The Cooper Ornithological Society 2011.

Active migration is associated with specific and consistent changes to gut microbiota in Calidris shorebirds.

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Risely, Alice; Waite, David W; Ujvari, Beata; Hoye, Bethany J; Klaassen, Marcel

2018-03-01

Gut microbes are increasingly recognised for their role in regulating an animal's metabolism and immunity. However, identifying repeatable associations between host physiological processes and their gut microbiota has proved challenging, in part because microbial communities often respond stochastically to host physiological stress (e.g. fasting, forced exercise or infection). Migratory birds provide a valuable system in which to test host-microbe interactions under physiological extremes because these hosts are adapted to predictable metabolic and immunological challenges as they undergo seasonal migrations, including temporary gut atrophy during long-distance flights. These physiological challenges may either temporarily disrupt gut microbial ecosystems, or, alternatively, promote predictable host-microbe associations during migration. To determine the relationship between migration and gut microbiota, we compared gut microbiota composition between migrating and non-migrating ("resident") conspecific shorebirds sharing a flock. We performed this across two sandpiper species, Calidris ferruginea and Calidris ruficollis, in north-western Australia, and an additional C. ruficollis population 3,000 km away in southern Australia. We found that migrants consistently had higher abundances of the bacterial genus Corynebacterium (average 28% abundance) compared to conspecific residents (average gut community variation when excluding Corynebacterium. Our findings suggest a consistent relationship between Corynebacterium and Calidris shorebirds during migration, with further research required to identify causal mechanisms behind the association, and to elucidate functionality to the host. However, outside this specific association, migrating shorebirds broadly maintained gut community structure, which may allow them to quickly recover gut function after a migratory flight. This study provides a rare example of a repeatable and specific response of the gut microbiota to a

Intestinal Microbiota and Species Diversity of Campylobacter and Helicobacter spp. in Migrating Shorebirds in Delaware Bay

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Using rDNA sequencing analysis, we examined the bacterial diversity and the presence of opportunistic bacterial pathogens (i.e., Campylobacter and Helicobacter) in Red Knot (Calidris canutus, n=40), Ruddy Turnstone (Arenaria interpres, n=35), and Semipalmated Sandpiper (Calidris ...

Does growth rate determine the rate of metabolism in shorebird chicks living in the arctic?

NARCIS (Netherlands)

Williams, Joseph B.; Tieleman, B. Irene; Visser, G. Henk; Ricklefs, Robert E.

2007-01-01

We measured resting and peak metabolic rates (RMR and PMR, respectively) during development of chicks of seven species of shorebirds: least sandpiper (Calidris minutilla; adult mass 20 22 g), dunlin (Calidris alpina; 56-62 g), lesser yellowlegs (Tringa flavipes; 88-92 g), short-billed dowitcher

Coping with the cold: an ecological context for the abundance and distribution of rock sandpipers during winter in upper Cook Inlet, Alaska

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Ruthrauff, Daniel R.; Gill, Robert E.; Tibbitts, T. Lee

2013-01-01

Shorebirds are conspicuous and abundant at high northern latitudes during spring and summer, but as seasonal conditions deteriorate, few remain during winter. To the best of our knowledge, Cook Inlet, Alaska (60.6˚ N, 151.6˚ W), is the world’s coldest site that regularly supports wintering populations of shorebirds, and it is also the most northerly nonbreeding location for shorebirds in the Pacific Basin. During the winters of 1997–2012, we conducted aerial surveys of upper Cook Inlet to document the spatial and temporal distribution and number of Rock Sandpipers (Calidris ptilocnemis) using the inlet. The average survey total was 8191 ± 6143 SD birds, and the average of each winter season’s highest single-day count was 13 603 ± 4948 SD birds. We detected only Rock Sandpipers during our surveys, essentially all of which were individuals of the nominate subspecies (C. p. ptilocnemis). Survey totals in some winters closely matched the population estimate for this subspecies, demonstrating the region’s importance as a nonbreeding resource to the subspecies. Birds were most often found at only a handful of sites in upper Cook Inlet, but shifted their distribution to more southerly locations in the inlet during periods of extreme cold. Two environmental factors allow Rock Sandpipers to inhabit Cook Inlet during winter: 1) an abundant bivalve (Macoma balthica) food source and 2) current and tidal dynamics that keep foraging substrates accessible during all but extreme periods of cold and ice accretion. C. p. ptilocnemis is a subspecies of high conservation concern for which annual winter surveys may serve as a relatively inexpensive population-monitoring tool that will also provide insight into adaptations that allow these birds to exploit high-latitude environments in winter.

Mercury, Lead, Cadmium, Arsenic, Chromium and Selenium in Feathers of Shorebirds during Migrating through Delaware Bay, New Jersey: Comparing the 1990s and 2011/2012

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Joanna Burger

2015-02-01

Full Text Available Understanding temporal changes in contaminant levels in coastal environments requires comparing levels of contaminants from the same species from different time periods, particularly if species are declining. Several species of shorebirds migrating through Delaware Bay have declined from the 1980s to the present. To evaluate some contaminants as cause for the declines, we examine levels of mercury, lead, cadmium, arsenic, chromium and selenium in feathers of red knot (Calidris canutus, N = 46 individuals, semipalmated sandpiper (Calidris pusilla, N = 70 and sanderling (Calidris alba, N = 32 migrating through Delaware Bay, New Jersey, USA, from 1991 to 1992 (N = 40, 1995 (N = 28, and 2011–2012 (N = 80 to determine if levels have changed. We found: (1 arsenic, chromium, and lead increased in red knot and decreased in semipalmated sandpiper; (2 cadmium decreased in semipalmated sandpipers; (3 mercury decreased in red knot and sanderlings; (4 selenium decreased in red knot and increased in semipalmated sandpipers. In 2011/2012 there were significant interspecific differences for arsenic, mercury and selenium. Except for selenium, the element levels were well below levels reported for feathers of other species. The levels in feathers in red knots, sanderling, and semipalmated sandpipers from Delaware Bay in 2011/2012 were well below levels in feathers that are associated with effect levels, except for selenium. Selenium levels ranged from 3.0 µg·g−1 dry weight to 5.8 µg·g−1 (semipalmated sandpiper, within the range known to cause adverse effects, suggesting the need for further examination of selenium levels in birds. The levels of all elements were well below those reported for other marine species, except for selenium, which was near levels suggesting possible toxic effects.

Ecological correlates of variable organ sizes and fat loads in the most northerly-wintering shorebirds

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Ruthrauff, Daniel R.; Dekinga, Anne; Gill, R.E.; Summers, R.W.; Piersma, Theunis

2013-01-01

Shorebirds at northern latitudes during the nonbreeding season typically carry relatively large lipid stores and exhibit an up-regulation of lean tissues associated with digestion and thermogenesis. Intraspecific variation in these tissues across sites primarily reflects differences in environmental conditions. Rock (Calidris ptilocnemis (Coues, 1873)) and Purple (Calidris maritima (Brünnich, 1764)) sandpipers are closely related species having the most northerly nonbreeding distributions among shorebirds, living at latitudes up to 61°N in Cook Inlet, Alaska, and up to 71°N in northern Norway, respectively. Cook Inlet is the coldest known site used by nonbreeding shorebirds, and the region’s mudflats annually experience extensive coverage of foraging sites by sea and shore-fast ice. Accordingly, Rock Sandpipers increase their fat stores to nearly 20% of body mass during winter. In contrast, Purple Sandpipers exploit predictably ice-free rocky intertidal foraging sites and maintain low (food resources.

Local and global influences on population declines of coastal waders: Purple Sandpiper Calidris maritima numbers in the Moray Firth, Scotland

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Summers, Ron W.; Foster, Simon; Swann, Bob; Etheridge, Brian

2012-05-01

Declines in numbers by several wader species in Britain have been linked to climate change, but the mechanism for the declines has rarely been explored. Britain lies at the northern end of the East Atlantic Flyway, and supports 1.3 million out of the Flyway's 8.5 million coastal waders (Charadrii) in winter and the Purple Sandpiper is one of the species whose numbers have declined. Here, we examine the dynamics of the decline as observed in the Moray Firth, northeast Scotland, investigating whether the decline was due to poorer apparent survival (return rate) or poorer recruitment of young birds. The maximum number in the Moray Firth declined from 860 in 1987/88 to 236 in 2006/07, with some increase during winters 2007/08 and 2008/09. At the three main high-tide roosts (Balintore, Lossiemouth and Buckie) the maximum combined number declined from 574 to 90. Changes in survival and recruitment (percentage of first-year birds) were examined at these roosts from captured samples, which were ringed and recaptured. There were no significant changes between winters in survival rates, nor were there differences between the survival rates of age groups (first-year and adult) or bill size groups, which represented birds of different sex and breeding origin. Annual survival estimates for the three roosts ranged from 72 to 77%. The percentage of first-year birds varied among roosts and years; the lowest values were during the late 1980s/early 1990s and early 2000s. A free-running population model incorporating varying percentages of first-year birds and constant mortality for each roost provided a plausible explanation for the decline. Although modelled numbers followed the observed pattern, a discrepancy in one year was carried forward in subsequent years, so that the fit with the observed numbers was parallel rather than similar. However, it seems that the decline in numbers was largely due to poorer recruitment. We discuss whether breeding success had declined, whether the

Feeding ecology of arctic-nesting sandpipers during spring migration through the prairie pothole region

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Eldridge, J.L.; Krapu, G.L.; Johnson, D.H.

2009-01-01

We evaluated food habits of 4 species of spring-migrant calidrid sandpipers in the Prairie Pothole Region (PPR) of North Dakota. Sandpipers foraged in several wetland classes and fed primarily on aquatic dipterans, mostly larvae, and the midge family Chironomidae was the primary food eaten. Larger sandpiper species foraged in deeper water and took larger larvae than did smaller sandpipers. The diverse wetland habitats that migrant shorebirds use in the PPR suggest a landscape-level approach be applied to wetland conservation efforts. We recommend that managers use livestock grazing and other tools, where applicable, to keep shallow, freshwater wetlands from becoming choked with emergent vegetation limiting chironomid production and preventing shorebird use.

Novel and cross-species microsatellite markers for parentage analysis in Sanderling

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Luttikhuizen, P.C.; Bol, A.; Witte, H.; van Bleijswijk, J.; Haddrath, O.; Baker, A.J.; Piersma, T.; Reneerkens, J.; Piersma, T.

2011-01-01

We isolated and tested six novel microsatellite loci in Sanderling (Calidris alba) from Greenland for paternity analyses. In addition, we tested 11 already published microsatellite markers which were originally developed for the congeneric species, the Pectoral Sandpiper (C. melanotos). All loci

DNA barcoding and phylogeny of Calidris and Tringa (Aves: Scolopacidae).

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Huang, Zuhao; Tu, Feiyun

2017-07-01

The avian genera Calidris and Tringa are the largest of the widespread family of Scolopacidae. The phylogeny of members of the two genera is still a matter of controversial. Mitochondrial cytochrome c oxidase subunit I (COI) can serve as a fast and accurate marker for the identification and phylogeny of animal species. In this study, we analyzed the COI barcodes of thirty-one species of the two genera. All the species had distinct COI sequences. Two hundred and twenty-one variable sites were identified. Kimura two-parameter distances were calculated between barcodes. Neighbor-joining and maximum likelihood methods were used to construct phylogenetic trees. All the species could be discriminated by their distinct clades in the phylogenetic trees. The phylogenetic trees grouped all the species of Calidris and Tringa into different monophyletic clade, respectively. COI data showed a well-supported phylogeny for Calidris and Tringa species.

Behavioural evidence for heat-load problems in Great Knots in tropical Australia fuelling for long-distance flight

NARCIS (Netherlands)

Battley, PF; Rogers, DI; Piersma, T; Koolhaas, A; Battley, Phil F.; Rogers, Danny I.

2003-01-01

Migratory shorebirds that live in the tropics prior to embarking on long (> 5000 km) flights may face heat-load problems. The behaviour of a large sandpiper, the Great Knot (Calidris tenuirostris), was studied in Roebuck Bay, north-west Australia, from February to April 2000. We determined the

Anesthesia in a Baird's tapir (Tapirus bairdii).

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Trim, C M; Lamberski, N; Kissel, D I; Quandt, J E

1998-06-01

A Baird's tapir (Tapirus bairdii) was satisfactorily immobilized on two occasions with i.m. detomidine (0.065-0.13 mg/kg) and butorphanol (0.13-0.2 mg/kg). On the second occasion, anesthesia was induced by i.v. administration of ketamine (2.2 mg/kg). Twenty minutes later, endotracheal intubation was performed after an additional i.v. injection of ketamine (1.5 mg/kg). Anesthesia was maintained with isoflurane, which provided excellent conditions for radiology and surgery. Anesthesia was associated with hypoxemia when the tapir was allowed to breathe air and with hypoventilation. Mean arterial pressure remained satisfactory. No antagonist drugs were administered, and recovery from anesthesia was rapid and smooth.

Wind effects on prey availability: How northward migrating waders use brackish and hypersaline lagoons in the sivash, Ukraine

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Verkuil, Yvonne; Koolhaas, Anita; Van Der Winden, Jan

Large numbers of waders migrating northward in spring use the Sivash, a large system of shallow, brackish and hypersaline lagoons in the Black Sea and Azov Sea region (Ukraine). The bottoms of these lagoons are often uncovered by the wind. Hence, for waders the time and space available for feeding depend on wind conditions. In hypersaline lagoons the benthic and pelagic fauna was very poor, consisting mainly of chironomid larvae (0.19 g AFDM·m -2) and brine shrimps Artemia salina, respectively. Brine shrimp abundance was correlated with salinity, wind force, wind direction and water depth. Dunlin Calidris alpina and curlew sandpiper Calidris ferruginea were the only species feeding on brine shrimp. As brine shrimp densities are higher in deeper water, smaller waders such as broad-billed sandpipers Limicola falcinellus are too short-legged to reach exploitable densities of brine shrimp. In brackish lagoons the benthic and pelagic fauna was rich, consisting of polychaetes, bivalves, gastropods, chironomid larvae, isopods and amphipods (8.9 to 30.5 g AFDM·m -2), but there were no brine shrimps. Prey biomass increased with the distance from the coast, being highest on the site that was most frequently inundated. Dunlin, broad-billed sandpiper and grey plover Pluvialis squatarola were the most abundant birds in the brackish lagoon. Due to the effects of wind-tides only a small area was usually available as a feeding site. Gammarus insensibilis was the alternative prey resource in the water layer, and their density varied with wind direction in the same way as brine shrimp. Curlew sandpipers and dunlins in the hypersaline lagoons and broad-billed sandpipers in the brackish lagoons often changed feeding sites, probably following the variation in prey availability. Only because of the large size and variety of lagoons are waders in the Sivash always able to find good feeding sites.

Adición a los registros de tapir centroamericano (Tapirus bairdii en Oaxaca, México Addition to the records of Baird's Tapir (Tapirus bairdii in Oaxaca, Mexico

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Christian Alejandro Delfín-Alfonso

2008-12-01

Full Text Available En el mes de febrero de 2007, en el municipio de Santo Domingo Ingenio, distrito de Juchitán, Oaxaca, obtuvimos el registro de un ejemplar de tapir centroamericano (Tapirus bairdii mediante una fotografía proporcionada por los habitantes del sitio. La foto que fue tomada en el 2005, durante la época de lluvias, muestra un tapir adulto cazado a 1.5 km al norte de Santo Domingo. Es el registro más reciente de tapir en Oaxaca y sugiere que éste probablemente se desplazó de la zona montañosa de Los Chimalapas hacia el istmo de Tehuantepec.In February 2007, in the municipality of Santo Domingo Ingenio, Juchián District, Oaxaca state, we obtained the record of an individual of Baird's Tapir (Tapirus bairdii from a photograph provided by the inhabitants of the site. The photograph was taken in 2005 during the rainy season, showing a dead adult tapir which was hunted at only 1.5 km north from Santo Domingo town. This is the most recent record of Baird-Tapir in the state of Oaxaca and suggests that this individual probably moved from the mountainous zone of Los Chimalapas towards the Itsmus of Tehuantepec.

Age-related differences in common Sandpiper Tringa hypoleucos ...

African Journals Online (AJOL)

Adults and juveniles in the tail-depressed posture were dominant in aggressive interactions than birds in the tail-level posture. In mixed flocks of foraging sandpipers, four possible types of aggressive interactions occurred. Adult over juvenile interactions occurred more frequently than expected, and juvenile over adult ...

PRESENCE OF RED KNOT (CALIDRIS CANUTUS) IN ITE WETLANDS, TACNA, PERU

OpenAIRE

Jhonson K. Vizcarra

2012-01-01

The presence of Red Knot (Calidris canutus, Linnaeus 1758) in Ite Wetlands, Tacna, Peru is documented. Two individuals were observed in October 2011. This species had only one occurrence without details in this area.

[Duration of the pre-nesting period and its relation with social organization in sandpipers (Charadrii, Aves) nesting in north-east Yakutia].

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Gavrilov, V V

2013-01-01

Investigations were carried out at two stations of Ornithological Unit, IBPN FEB RAS, located in Nizhnekolymsk District, Yakutia, starting from May 18-20 in 1984, 1985, 1987, 1988 and 1990. Duration of the pre-nesting period in 11 sandpiper species with different social organization was studied and compared with each other by allometric equations. As a characteristic of bird size the body mass was selected. Sandpipers come flying to the tundra at almost critical temperatures, to begin breeding as early as possible. Tining of breeding depends on birds feeding manner and the proximity to sites of overwintering. Duration of the pre-nesting period is invariable for every bird species and sex. There are sexual distinctions in time spent for the pre-nesting period in jointly-nesting sandpipers. The exponents in allometric equations that relate duration of the pre-nesting period with body mass are constant within a particular sex and differ between males and females. In different sexes, time spent for the pre-nesting period depends on mating, parental, and territorial systems. In sandpipers' males and females, this time is determined by the type of social organization. Relatively large sandpiper species seek to shortening of the pre-nesting period calendar time, which constrains their social organization. Monogamy and pair parental care lead to a necessity for spatial population structure to be controlled more strictly and maintained for a longer time. This, in turn, causes the increasing of males' time expenditures for such a behavior.

Feather mites of Calidris fuscicollis (Aves: Scolopacidae) in Brazil

OpenAIRE

Gomes, S. N.; Pesenti, T. C.; Cirne, M. P.; Müller, G.

2015-01-01

Abstract During the period 2010-2012, eighty individuals of Calidris fuscicollis (Vieillot, 1819) were collected on the southern coast of Rio Grande do Sul, Brazil, with the objective of determining the presence of feather mites. Of the 80 birds examined, 32.5% were infested by mites, identified as Avenzoaria calidridis (Oudemans, 1904) (Avenzoariidae) (31.25%), Montchadskiana securicata (Megnin & Trouessart 1884) (Pterolichidae) (22.5%) and Alloptes limosae (Dubinin, 1951) (Alloptidae) (6.25...

Behavioral response of Corophium volutator to shorebird predation in the upper Bay of Fundy, Canada.

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Elizabeth C MacDonald

Full Text Available Predator avoidance is an important component of predator-prey relationships and can affect prey availability for foraging animals. Each summer, the burrow-dwelling amphipod Corophium volutator is heavily preyed upon by Semipalmated Sandpipers (Calidris pusilla on mudflats in the upper Bay of Fundy, Canada. We conducted three complementary studies to determine if adult C. volutator exhibit predator avoidance behavior in the presence of sandpipers. In a field experiment, we monitored vertical distribution of C. volutator adults in bird exclosures and adjacent control plots before sandpipers arrived and during their stopover. We also made polymer resin casts of C. volutator burrows in the field throughout the summer. Finally, we simulated shorebird pecking in a lab experiment and observed C. volutator behavior in their burrows. C. volutator adults were generally distributed deeper in the sediment later in the summer (after sandpipers arrived. In August, this response was detectably stronger in areas exposed to bird predation than in bird exclosures. During peak predator abundance, many C. volutator adults were beyond the reach of feeding sandpipers (>1.5 cm deep. However, burrow depth did not change significantly throughout the summer. Detailed behavioral observations indicated that C. volutator spent more time at the bottom of their burrow when exposed to a simulated predator compared to controls. This observed redistribution suggests that C. volutator adults move deeper into their burrows as an anti-predator response to the presence of sandpipers. This work has implications for predators that feed on burrow-dwelling invertebrates in soft-sediment ecosystems, as density may not accurately estimate prey availability.

Avian influenza virus antibodies in Pacific Coast Red Knots (Calidris canutus rufa)

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Johnson, James A.; DeCicco, Lucas H.; Ruthrauff, Daniel R.; Krauss, Scott; Hall, Jeffrey S.

2014-01-01

Prevalence of avian influenza virus (AIV) antibodies in the western Atlantic subspecies of Red Knot (Calidris canutus rufa) is among the highest for any shorebird. To assess whether the frequency of detection of AIV antibodies is high for the species in general or restricted only to C. c. rufa, we sampled the northeastern Pacific Coast subspecies of Red Knot (Calidris canutus roselaari) breeding in northwestern Alaska. Antibodies were detected in 90% of adults and none of the chicks sampled. Viral shedding was not detected in adults or chicks. These results suggest a predisposition of Red Knots to AIV infection. High antibody titers to subtypes H3 and H4 were detected, whereas low to intermediate antibody levels were found for subtypes H10 and H11. These four subtypes have previously been detected in shorebirds at Delaware Bay (at the border of New Jersey and Delaware) and in waterfowl along the Pacific Coast of North America.

Embryonal rhabdomyosarcoma in an immature Baird's tapir (Tapirus bairdii).

Science.gov (United States)

Bonar, Christopher J; Lewandowski, Albert H; Skowronek, Anthony J

2007-03-01

An immature Baird's tapir (Tapirus bairdii) with a history of seizure-like episodes developed signs of respiratory disease. The initial clinical diagnosis was pneumonia, and antibiotic therapy was started. The animal failed to improve after 14 days of therapy and developed unilateral, bloody nasal discharge. Endoscopic examination and radiography revealed a soft tissue mass in the nasopharynx depressing the soft palate. The tapir died 32 days after initial presentation. Histologic examination of the mass demonstrated a mesenchymal tumor composed of spindle cells with elongate nuclei forming densely packed fascicles. The neoplastic spindle cells showed prominent cross-striations. Immunohistochemistry revealed the cells to be positive for desmin and myoglobin, but negative for smooth muscle actin, confirming diagnosis of rhabdomyosarcoma. Embryonal rhabdomyosarcoma is the most common nasopharyngeal soft tissue tumor of humans, and it has been reported infrequently in dogs, horses, and pigs. Neoplasia should be a differential diagnosis in cases of unilateral nasal discharge and inspiratory stridor, even in young animals.

Inorganic and organic contaminants in Alaskan shorebird eggs.

Science.gov (United States)

Saalfeld, David T; Matz, Angela C; McCaffery, Brian J; Johnson, Oscar W; Bruner, Phil; Lanctot, Richard B

2016-05-01

Many shorebird populations throughout North America are thought to be declining, with potential causes attributed to habitat loss and fragmentation, reduced prey availability, increased predation, human disturbance, and increased exposure to environmental pollutants. Shorebirds may be particularly vulnerable to contaminant exposure throughout their life cycle, as they forage primarily on invertebrates in wetlands, where many contaminants accumulate disproportionately in the sediments. Therefore, it is important to document and monitor shorebird populations thought to be at risk and assess the role that environmental contaminants may have on population declines. To investigate potential threats and provide baseline data on shorebird contaminant levels in Alaskan shorebirds, contaminant concentrations were evaluated in shorebird eggs from 16 species residing in seven geographic distinct regions of Alaska. Similar to previous studies, low levels of most inorganic and organic contaminants were found, although concentrations of several inorganic and organic contaminants were higher than those of previous studies. For example, elevated strontium levels were observed in several species, especially black oystercatcher (Haematopus bachmani) sampled in Prince William Sound, Alaska. Additionally, contaminant concentrations varied among species, with significantly higher concentrations of inorganic contaminants found in eggs of pectoral sandpiper (Calidris melanotos), semipalmated sandpiper (Calidris pusilla), black oystercatcher, and bar-tailed godwit (Limosa lapponica). Similarly, significantly higher concentrations of some organic contaminants were found in the eggs of American golden plover (Pluvialis dominica), black-bellied plover (Pluvialis squatarola), pacific golden plover (Pluvialis fulva), bar-tailed godwit, and semipalmated sandpiper. Despite these elevated levels, current concentrations of contaminants in shorebird eggs suggest that breeding environments are

Predicting breeding shorebird distributions on the Arctic Coastal Plain of Alaska

Science.gov (United States)

Saalfeld, Sarah T.; Lanctot, Richard B.; Brown, Stephen C.; Saalfeld, David T.; Johnson, James A.; Andres, Brad A.; Bart, Jonathan R.

2013-01-01

The Arctic Coastal Plain (ACP) of Alaska is an important region for millions of migrating and nesting shorebirds. However, this region is threatened by climate change and increased human development (e.g., oil and gas production) that have the potential to greatly impact shorebird populations and breeding habitat in the near future. Because historic data on shorebird distributions in the ACP are very coarse and incomplete, we sought to develop detailed, contemporary distribution maps so that the potential impacts of climate-mediated changes and development could be ascertained. To do this, we developed and mapped habitat suitability indices for eight species of shorebirds (Black-bellied Plover [Pluvialis squatarola], American Golden-Plover [Pluvialis dominica], Semipalmated Sandpiper [Calidris pusilla], Pectoral Sandpiper [Calidris melanotos], Dunlin [Calidris alpina], Long-billed Dowitcher [Limnodromus scolopaceus], Red-necked Phalarope [Phalaropus lobatus], and Red Phalarope [Phalaropus fulicarius]) that commonly breed within the ACP of Alaska. These habitat suitability models were based on 767 plots surveyed during nine years between 1998 and 2008 (surveys were not conducted in 2003 and 2005), using single-visit rapid area searches during territory establishment and incubation (8 June, 1 July). Species specific habitat suitability indices were developed and mapped using presence-only modeling techniques (partitioned Mahalanobis distance) and landscape environmental variables. For most species, habitat suitability was greater at lower elevations (i.e., near the coast and river deltas) and lower within upland habitats. Accuracy of models was high for all species, ranging from 65 -98%. Our models predicted that the largest fraction of suitable habitat for the majority of species occurred within the National Petroleum Reserve-Alaska, with highly suitable habitat also occurring within coastal areas of the Arctic National Wildlife Refuge west to Prudhoe Bay.

Growth of Little Stint Calidris minuta chicks on the Taimyr Peninsula, Siberia

NARCIS (Netherlands)

Schekkerman, H; Nehls, G; Hotker, H; Tomkovich, PS; Kania, W; Chylarecki, P; Soloviev, M; Van Roomen, M

Growth of mass and linear body dimensions (bill, tarsus and wing length) was studied in the Little Stint Calidris minuta at several locations on the Taimyr Peninsula, Siberia (73 degrees-76 degrees N) in 1983-94. Little Stints fledged at near-adult body mass, at 15 days of age. Growth followed an

Plumage reflectance is not affected by preen wax composition in red knots Calidris canutus

NARCIS (Netherlands)

Reneerkens, J; Korsten, P

It has recently been shown that sandpipers (Scolopacidae) abruptly switch the chemical composition of their preen gland secretions from mono- to diester waxes just before the period of courtship. The timing and context of the shift suggested that diesters could provide a visible quality signal

Southward migration and fuel deposition of Red Knots Calidris canutus

OpenAIRE

Helseth, Anders; Lindström, Åke; Stervander, Martin

2005-01-01

We compared the differences between spring and autumn in migration speed, fuelling rates and fuel loads of migrating Red Knots Calidris canutus. As a basis we used ringing data from Ottenby Bird Observatory, southeastern Sweden, collected 1948–2003, with morphometrical data from 1990–2003. Numbers ringed varied between 0 and 301 per year (average 56). Morphometrics, recoveries and recaptures of ringed birds indicated that most birds belonged to the Afro-Siberian subspecies C. c. canutus, poss...

Do Uniparental Sanderlings Calidris alba Increase Egg Heat Input to Compensate for Low Nest Attentiveness?

NARCIS (Netherlands)

Reneerkens, J.; Grond, K.; Schekkerman, H.; Tulp, I.Y.M.; Piersma, Th.

2011-01-01

Birds breeding in cold environments regularly have to interrupt incubation to forage, causing a trade-off between two mutually exclusive behaviours. Earlier studies showed that uniparental Arctic sandpipers overall spend less time incubating their eggs than biparental species, but interspecific

Endogenous circannual rhythmicity in body mass, molt, and plumage of Great Knots (Calidris tenuirostris)

NARCIS (Netherlands)

Piersma, Theunis; Brugge, Maarten; Spaans, Bernard; Battley, Phil F.; Handel, C.M.

Four Great Knots (Calidris tenuirostris) were kept for six years in a constant-temperature indoor aviary. For two of those six years, they were kept under photoperiodic conditions that mimicked natural changes in daylength for wild birds, followed by four years under a constant photoperiod

Modelling phenotypic flexibility : an optimality analysis of gizzard size in Red Knots Calidris canutus

NARCIS (Netherlands)

van Gils, Jan A.; Piersma, Theunis; Dekinga, Anne; Battley, Phil F.

2006-01-01

Reversible phenotypic changes, such as those observed in nutritional organs of long-distance migrants, increasingly receive the attention of ornithologists. In this paper we review the cost-benefit studies that have been performed on the flexible gizzard of Red Knots Calidris cunutus. By varying the

Modelling phenotypic flexibility: an optimality analysis of gizzard size in Red Knots (Calidris canutus)

NARCIS (Netherlands)

Van Gils, J.A.; Piersma, T.; Dekinga, A.; Battley, P.F.

2006-01-01

Reversible phenotypic changes, such as those observed in nutritional organs of long-distance migrants, increasingly receive the attention of ornithologists. In this paper we review the cost-benefit studies that have been performed on the flexible gizzard of Red Knots Calidris canutus. By varying the

Feeding-Danger Trade-Offs Underlie Stopover Site Selection by Migrants

Directory of Open Access Journals (Sweden)

Andrea C. Pomeroy

2008-06-01

Full Text Available To migrate successfully, birds need to store adequate fat reserves to fuel each leg of the journey. Migrants acquire their fuel reserves at stopover sites; this often entails exposure to predators. Therefore, the safety attributes of sites may be as important as the feeding opportunities. Furthermore, site choice might depend on fuel load, with lean birds more willing to accept danger to obtain good feeding. Here, we evaluate the factors underlying stopover-site usage by migrant Western Sandpipers (Calidris mauri on a landscape scale. We measured the food and danger attributes of 17 potential stopover sites in the Strait of Georgia and Puget Sound region. We used logistic regression models to test whether food, safety, or both were best able to predict usage of these sites by Western Sandpipers. Eight of the 17 sites were used by sandpipers on migration. Generally, sites that were high in food and safety were used, whereas sites that were low in food and safety were not. However, dangerous sites were used if there was ample food abundance, and sites with low food abundance were used if they were safe. The model including both food and safety best-predicted site usage by sandpipers. Furthermore, lean sandpipers used the most dangerous sites, whereas heavier birds (which do not need to risk feeding in dangerous locations used safer sites. This study demonstrates that both food and danger attributes are considered by migrant birds when selecting stopover sites, thus both these attributes should be considered to prioritize and manage stopover sites for conservation.

Bayesian analysis of Jolly-Seber type models

Science.gov (United States)

Matechou, Eleni; Nicholls, Geoff K.; Morgan, Byron J. T.; Collazo, Jaime A.; Lyons, James E.

2016-01-01

We propose the use of finite mixtures of continuous distributions in modelling the process by which new individuals, that arrive in groups, become part of a wildlife population. We demonstrate this approach using a data set of migrating semipalmated sandpipers (Calidris pussila) for which we extend existing stopover models to allow for individuals to have different behaviour in terms of their stopover duration at the site. We demonstrate the use of reversible jump MCMC methods to derive posterior distributions for the model parameters and the models, simultaneously. The algorithm moves between models with different numbers of arrival groups as well as between models with different numbers of behavioural groups. The approach is shown to provide new ecological insights about the stopover behaviour of semipalmated sandpipers but is generally applicable to any population in which animals arrive in groups and potentially exhibit heterogeneity in terms of one or more other processes.

Parásitos del tapir centroamericano Tapirus bairdii (Perissodactyla: Tapiridae en Chiapas, México

Directory of Open Access Journals (Sweden)

Epigmenio Cruz Aldán

2006-06-01

Full Text Available Se recolectaron 19 muestras de excretas del tapir centroamericano (Tapirus bairdii en la Reserva "La Sepultura" (marzo a julio de 1999, así como un muestreo directo a un tapir macho de la Reserva "Montes Azules" (Chiapas, México. Se analizaron con cinco técnicas (flotación, MacMaster, micrometría, sedimentación de Ritchie y cuantitativa de Ferreira. Además se recolectaron muestras en piel de animales capturados en en las dos reservas y en una pareja de zoológico proveniente de Tuxtla Gutiérrez, Chiapas. Se hallaron nematodos y protozoarios: Agriostomun sp., Lacandoria sp., Neomurshidia sp., Trichostrongylus sp., Strongylus sp., Brachylumus sp., y un ancilostomaideo aun por identificar. Además se informa la presencia de Eimeria sp., y Balantidium coli. Los ácaros hallados fueron; Dermacentor halli, Dermacentor latus, Amblyomma cajannense, Amblyomma coelebs, Amblyomma ovale, Anocentor nitens e Ixodes bicornis.Parasites of the Central American tapir Tapirus bairdii (Perissodactyla: Tapiridae in Chiapas, Mexico. We analyzed 19 samples of Baird´s tapir feces from La Sepultura Biosphere Reserve, collected between March and July 1999. We also took samples directly from a male tapir captured at the Montes Azules Biosphere Reserve. Both reserves are in Chiapas, Mexico. We used five techniques: flotation, MacMaster, micrometric, Ritchie’s sedimentation and Ferreira´s quantitative. In addition, we collected ectoparasites from animals captured in both reserves and from a captive couple from Tuxtla Gutierrez, Chiapas. These nematodes and protozoans were found: Agriostomun sp., Lacandoria sp., Neomurshidia sp., Trichostrongylus sp., Strongylus sp., Brachylumus sp, and an unidentified species of ancilostomaide. We also found Eimeria sp. and Balantidium coli, as well as the mites Dermacentor halli, Dermacentor latus, Amblyomma cajannense, Amblyomma coelebs, Amblyomma ovale, Anocentor nitens and Ixodes bicornis. Rev. Biol. Trop. 54(2: 445

[Relative abundance, population structure, habitat preferences and activity patterns of Tapirus bairdii (Perissodactyla: Tapiridae), in Chimalapas forest, Oaxaca, Mexico].

Science.gov (United States)

Lira-Torres, Iván; Briones-Salas, Miguel; Sánchez-Rojas, Gerardo

2014-12-01

Baird's tapir (Tapirus bairdii) is endangered primarily because of habitat loss and fragmentation, and overhunting throughout its distribution range. One of the priority land areas for the conservation of this species is the Northern part of its range in the Chimalapas forest, Oaxaca. The aim of this research was to determine the relative abundance, population struc- ture, habitat preferences and activity patterns of Baird's tapir (Tapirus bairdii) in the Chimalapas forest, Oaxaca, Mexico, through the non-invasive technique of camera-trap sampling. A total of five sampling sessions were undertaken among 2009-2013, and used a total of 30 camera-traps in each period. The determinant factor of the sampling design was the hunting between two study areas. A total sampling effort of 9000 trap-days allowed to estimate an index of relative abundance (IRA) of 6.77 tapir photographs/1,000 trap-days (n = 61). IRA varied significantly between sampling stations (Mann-Whitney, p dry season in tropical rain forest without hunting (χ2, p tropical rain forest and secondary vegetation habitats showed higher photo frequency than expected from random (χ2, p forest appears to be the second most important terrestrial priority ecoregion, just after the Mayan Forest (Campeche, Chiapas, Quintana Roo), for the conservation of tapir populations, not only for Mexico but also for Central America.

Use of aquaculture ponds and other habitats by autumn migrating shorebirds along the lower Mississippi river.

Science.gov (United States)

Lehnen, Sarah E; Krementz, David G

2013-08-01

Populations of many shorebird species are declining; habitat loss and degradation are among the leading causes for these declines. Shorebirds use a variety of habitats along interior migratory routes including managed moist soil units, natural wetlands, sandbars, and agricultural lands such as harvested rice fields. Less well known is shorebird use of freshwater aquaculture facilities, such as commercial cat- and crayfish ponds. We compared shorebird habitat use at drained aquaculture ponds, moist soil units, agricultural areas, sandbars and other natural habitat, and a sewage treatment facility in the in the lower Mississippi River Alluvial Valley (LMAV) during autumn 2009. Six species: Least Sandpiper (Calidris minutilla), Killdeer (Charadrius vociferous), Semipalmated Sandpiper (Calidris pusilla), Pectoral Sandpiper (C. melanotos), Black-necked Stilt (Himantopus himantopus), and Lesser Yellowlegs (Tringa flavipes), accounted for 92 % of the 31,165 individuals observed. Sewage settling lagoons (83.4, 95 % confidence interval [CI] 25.3-141.5 birds/ha), drained aquaculture ponds (33.5, 95 % CI 22.4-44.6 birds/ha), and managed moist soil units on public lands (15.7, CI 11.2-20.3 birds/ha) had the highest estimated densities of shorebirds. The estimated 1,100 ha of drained aquaculture ponds available during autumn 2009 provided over half of the estimated requirement of 2,000 ha by the LMAV Joint Venture working group. However, because of the decline in the aquaculture industry, autumn shorebird habitats in the LMAV may be limited in the near future. Recognition of the current aquaculture habitat trends will be important to the future management activities of federal and state agencies. Should these aquaculture habitat trends continue, there may be a need for wildlife biologists to investigate other habitats that can be managed to offset the current and expected loss of aquaculture acreages. This study illustrates the potential for freshwater aquaculture to

Molecular analysis of intact preen waxes of Calidris canutus (Aves : Scolopacidae) by gas chromatography/mass spectrometry

NARCIS (Netherlands)

Dekker, MHA; Piersma, T; Damste, JSS; Dekker, Marlèn H.A.; Sinninghe Damsté, Jaap S.

The intact preen wax esters of the red knot Calidris canutus were studied with gas chromatography/mass spectrometry (GC/MS) and GC/MS/MS. In this latter technique, transitions from the molecular ion to fragment ions representing the fatty acid moiety of the wax esters were measured, providing

Within-population variation in mating system and parental care patterns in the sanderling (Calidris alba) in northeast Greenland

NARCIS (Netherlands)

Reneerkens, Jeroen; van Veelen, Pieter; van der Velde, Marco; Luttikhuizen, Pieternella; Piersma, Theunis

Sandpipers and allies (Scolopacidae) show an astounding diversity in mating and parental care strategies. Comparative studies have tried to interpret this variation in terms of phylogenetic constraints and ecological shaping factors. In such analyses, mating and parental care systems are necessarily

Vision and touch in relation to foraging and predator detection : insightful contrasts between a plover and a sandpiper

NARCIS (Netherlands)

Martin, Graham R.; Piersma, Theunis

2009-01-01

Visual fields were determined in two species of shorebirds (Charadriiformes) whose foraging is guided primarily by different sources of information: red knots (Calidris canutus, tactile foragers) and European golden plovers (Pluvialis apricaria, visual foragers). The visual fields of both species

Seasonality in basal metabolic rate and thermal conductance in a long-distance migrant shorebird, the knot (Calidris canutus)

NARCIS (Netherlands)

Piersma, T.; Cadée, N.; Daan, S.

Knots Calidris canutus live highly seasonal lives, breeding solitarily on high arctic tundra and spending the non-breeding season in large social flocks in temperate to tropical estuaries. Their reproductive activities and physiological preparations for long flights are reflected in pronounced

Molecular analysis of intact preen waxes of Calidris Canutus (Aves: Scolopacidae) by GC/MS and GC/MS/MS

NARCIS (Netherlands)

Sinninghe Damsté, J.S.; Dekker, M.H.A.; Piersma, T.

2000-01-01

The intact preen wax esters of the red knot Calidris canutus were studied with gas chromatography/mass spectrometry (GC/MS) and GC/MS/MS. In this latter technique, transitions from the molecular ion to fragment ions representing the fatty acid moiety of the wax esters were measured, providing

Cost reduction in the cold: heat generated by terrestrial locomotion partly substitutes for thermoregulation costs in Knot Calidris canutus

NARCIS (Netherlands)

Bruinzeel, L.W.; Piersma, T.

1998-01-01

To test whether heat generated during locomotion substitutes for the thermoregulation cost, oxygen consumption of four post-absorptive temperate-wintering Knot Calidris canutus was measured at air temperatures of 25 degrees C (thermoneutral) and 10 degrees C (c. 10 degrees below the lower critical

Red Knots (Calidris canutus piersmai and C. c. rogersi) depend on a small threatened staging area in Bohai Bay, China

NARCIS (Netherlands)

Rogers, Danny I.; Yang, Hong-Yan; Hassell, Chris J.; Boyle, Adrian N.; Rogers, Ken G.; Chen, Bing; Zhang, Zheng-Wang; Piersma, Theunis

2010-01-01

We monitored numbers of Red Knots (Calidris canutus) staging in Bohai Bay, China (39 degrees 02'N, 118 degrees 15'E) on northward migration. Knots were identified to subspecies, and we systematically searched for colour-banded birds from the non-breeding grounds. We modelled migratory turnover, and

Small home ranges and high site fidelity in red knots (Calidris c. canutus) wintering on the Banc d'Arguin, Mauritania

NARCIS (Netherlands)

Leyrer, J; Spaans, B; Camara, M; Piersma, T

Using automated and manual radio-telemetry and resightings of individual colour-ringed birds, we assessed the daily use of space of red knots Calidris canutus canutus at a tropical wintering area along the Sahara coast, the Banc d'Arguin in Mauritania. Confirming earlier suggestions, we found that

Small home ranges and high site fidelity in red knots (Calidris c. canutus) wintering on the Banc d’Arguin, Mauritania

NARCIS (Netherlands)

Leyrer, Jutta; Spaans, Bernard; Camara, Mohamed; Piersma, Theunis; Bairlein, F.

2006-01-01

Using automated and manual radio-telemetry and resightings of individual colour-ringed birds, we assessed the daily use of space of red knots Calidris canutus canutus at a tropical wintering area along the Sahara coast, the Banc d’Arguin in Mauritania. Confirming earlier suggestions, we found that

SANDPIPER I (A comprehensive analysis programme for liquid moderated UO2 lattices)

International Nuclear Information System (INIS)

Alpiar, R.A.

1962-04-01

Methods of calculation for light water moderated reactors have recently been reviewed in AEEW R64. Calculation schemes for lattice parameters were presented which depended on the use of a number of IBM 704 and Perranti MERCURY Computer Programmes. SANDPIPER I is a comprehensive MERCURY programme designed to cover all the operations with a degree of accuracy adequate for survey calculations. The present version is restricted to regular or near regular UO 2 pin type lattices moderated by H 2 O, D 2 O, or organic liquids; it is planned to allow for greater flexibility in later versions of the programme. The present version is written in Autocode and requires a 4 drum machine. (author)

Mate fidelity and breeding site tenacity in a monogamous sandpiper, the black turnstone

Science.gov (United States)

Handel, C.M.; Gill, R.E.

2000-01-01

We examined the relationship between mate fidelity and breeding site tenacity during a 5-year study of the black turnstone, Arenaria melanocephala, a socially monogamous sandpiper breeding in subarctic Alaska. We tested the predictions of several hypotheses regarding the incidence of divorce and the benefits of fidelity to mate and breeding site. Interannual return rates to the breeding grounds (88% for males, 79% for females) were among the highest yet recorded for any scolopacid sandpiper, and 88% of returning birds nested on their previous year's territory. The annual divorce rate was only 11%, and mate fidelity was significantly linked to fidelity to territory but independent of sex and year. Males arrived in spring significantly earlier than their mates and interannual fidelity was influenced by the relative timing of arrival of pair members. Reunited pairs had significantly higher fledging success than new pairs formed after death or divorce. The incidence of divorce was unrelated to reproductive success the previous year, although birds nested significantly further away after failure than after a successful nesting attempt. Sightings of marked individuals suggested that members of pairs do not winter together, and breeding site tenacity provides a mechanism through which pair members can reunite. We reject the 'incompatibility' hypothesis for divorce in turnstones, and our data contradict predictions of the 'better option' hypothesis. Alternatively, we propose the 'bet-hedging' hypothesis to explain the occurrence of divorce, which transpires when an individual pairs with a new mate to avoid the cost of waiting for a previous mate to return. Such costs can include remaining unmated, if the former mate has died, or experiencing lower reproductive success because of delayed breeding.

ANNUAL AND SEASONAL-VARIATION IN THE FOOD-SUPPLY HARVESTABLE BY KNOT CALIDRIS-CANUTUS STAGING IN THE WADDEN SEA IN LATE SUMMER

NARCIS (Netherlands)

ZWARTS, L; BLOMERT, AM; WANINK, JH

The biomass of the macrobenthic animals living in intertidal flats of the Wadden Sea varies annually and seasonally. However, the variation in prey biomass harvestable by wading birds such as knot Calidris canutus, which feed mainly on the middle range of their prey size classes, is even larger. The

Role of the low-affinity glucocorticoid receptor in the regulation of behavior and energy metabolism in the migratory red knot Calidris canutus islandica

NARCIS (Netherlands)

Landys, MM; Piersma, T; Ramenofsky, M; Wingfield, JC; Wingfield, John C.

2004-01-01

Plasma corticosterone increases in association with migratory flight in the red knot Calidris canutus islandica, suggesting that corticosterone may promote migratory activity and/or energy mobilization in this species. This hypothesis is supported by general effects of glucocorticoids, which include

Tziminema unachi n. gen., n. sp. (Nematoda: Strongylidae: Strongylinae) parasite of Baird's tapir Tapirus bairdii from Mexico.

Science.gov (United States)

Güiris-Andrade, D M; Oceguera-Figueroa, A; Osorio-Sarabia, D; Pérez-Escobar, M E; Nieto-López, M G; Rojas-Hernández, N M; García-Prieto, L

2017-11-20

A new genus and species of nematode, Tziminema unachi n. gen., n. sp. is described from the caecum and colon of Baird's tapir Tapirus bairdii (Gill, 1865), found dead in the Reserva de la Biósfera El Triunfo, Chiapas State, in the Neotropical realm of Mexico. Tziminema n. gen. differs from the other nine genera included in the Strongylinae by two main characteristics: having 7-9 posteriorly directed tooth-like structures at the anterior end of the buccal capsule, and the external surface of the buccal capsule being heavily striated. Phylogenetic analyses of the DNA sequences of the mitochondrial cytochrome c oxidase and nuclear DNA, including a partial sequence of the internal transcribed spacer 1, 5.8S and a partial sequence of the internal transcribed spacer 2 of the new taxon, confirmed its inclusion in Strongylinae and its rank as a new genus.

The coexistence of Baird's tapir (Tapirus bairdii) and indigenous hunters in northeastern Honduras.

Science.gov (United States)

Dunn, Marc; Estrada, Nereyda; Smith, Derek A

2012-12-01

The Baird's tapir (Tapirus bairdii) is a popular game species throughout Central America, particularly among indigenous populations, and is currently endangered. Research on Miskitu hunting was conducted over 4 months in a remote region in northeastern Honduras that overlaps with the Río Plátano Biosphere Reserve. The hunting zone was mapped together with hunters and interviews were conducted with elders and other community members about tapir hunting. Results show that tapir harvesting is targeted toward specific habitats at specific times of year. Harvest rates for one year suggest that tapir hunting in the area exceeds estimates of maximum sustainable production. Nevertheless, field surveys reveal the presence of tapir within 1 km of the community, and its harvest tends to be nearby, in both forested and agricultural landscapes, suggesting that the animal has not been depleted in the area. It appears that the existence of forest areas adjacent to the hunting zone that do not experience hunting, together with the anthropogenic habitats created through shifting cultivation, are factors that help explain the presence of tapirs in the area. The article concludes with a discussion regarding the potential positive role of indigenous hunters in tapir conservation throughout its distribution range. © 2012 Wiley Publishing Asia Pty Ltd, ISZS and IOZ/CAS.

Roosting behavior of premigratory Dunlins (Calidris alpina)

Science.gov (United States)

Handel, Colleen M.; Gill, Robert E.

1992-01-01

We studied roosting behavior of Dunlins (Calidris alpina) during late summer along the coast of the Yukon-Kuskokwim Delta, Alaska, in relation to tidal cycle, time of day, time of season, and occurrence of predators. Within Angyoyaravak Bay, peak populations of 70,000-100,000 Dunlins occur each year. The major diurnal roost sites were adjacent to intertidal feeding areas, provided an unobstructed view of predators, and were close to shallow waters used for bathing. At one site studied intensively, roosting flocks formed at high water consistently during the day but rarely at night. On about 75% of the days, Dunlins also came to the roost at dawn and dusk when the tide was low. The size of the roosting flock, the length of time birds spent at the roost site, and behavior at the roost site were highly variable throughout the season and significantly affected by both tide level and time of day. Roosting behavior changed significantly between early and late August, as Dunlins underwent heavy wing and body molt, and began premigratory fattening. The reaction of Dunlins to potential predators, the formation of roosting flocks in response to light cues, and seasonal changes in social behavior at the roost site suggested that communal roosting behavior may be related not only to the risk of predation but also to behavior during migration.

Are population dynamics of shorebirds affected by El Niño/Southern Oscillation (ENSO) while on their non-breeding grounds in Ecuador?

Science.gov (United States)

O'Hara, Patrick D.; Haase, Ben J. M.; Elner, Robert W.; Smith, Barry D.; Kenyon, Jamie K.

2007-08-01

Declines in avian populations are a global concern, particularly for species that migrate between Arctic-temperate and tropical locations. Long-term population studies offer opportunities to detect and document ecological effects attributable to long-term climatic cycles such as the El Niño/Southern Oscillation (ENSO). In this study, we report possible population-level effects of such climatic cycles on shorebird species that use two non-breeding season sites in Ecuador (Santa Elena peninsula area, near La Libertad). During our 9-year study period (1991/1992-1999/2000), there was a particularly strong ENSO warm phase event during 1997/1998. Population trend data for three species of shorebird, Western Sandpipers ( Calidris mauri), Semipalmated Sandpipers ( C. pusilla), and Least Sandpipers ( C. minutilla), indicated abundances generally declined during the 1990s, but there was an increase in the proportion of first-year birds and their abundance in the years following the 1997/1998 ENSO warm phase. There was some support for variation in apparent survivorship associated with the onset of the ENSO warm phase event in our population models, based on capture-mark-recapture data. Following the 1997/1998 ENSO event onset, individuals for all three species were significantly lighter during the non-breeding season ( F1,3789 = 6.6, p = 0.01). Least-squares mean mass (controlling for size, sex and day of capture) for first-year birds dropped significantly more than for adults following ENSO (first-year mass loss = 0.69 ± 0.12 g; adult mass loss = 0.34 ± 0.11 g, F1,3789 = 5.31, p = 0.021), and least-squares mean mass dropped most during the period when sandpipers prepare for northward migration by gaining mass and moulting into breeding plumage. Least Sandpipers may have declined the most in mean mass following ENSO (0.76 ± 0.19 g), whereas Semipalmated Sandpipers were 0.52 ± 0.12 g lighter, and Western Sandpipers 0.40 ± 0.13 g lighter, but overall variation among

Ejaculate traits and sperm cryopreservation in the endangered Baird's tapir (Tapirus bairdii).

Science.gov (United States)

Pukazhenthi, Budhan S; Togna, Gina Della; Padilla, Luis; Smith, Diorene; Sanchez, Carlos; Pelican, Katey; Sanjur, Oris I

2011-01-01

There is little information on the reproductive biology of the male Baird's tapir (Tapirus bairdii). In this study, we characterized the ejaculate traits and evaluated the efficacy of 2 cryodiluents on sperm cryosurvival. Ejaculates were assessed for volume, pH, sperm motility, forward progression, osmolality, sperm concentration, sperm morphology, and acrosomal integrity. For cryopreservation, ejaculates with >50% total sperm motility were washed, and sperm pellets were resuspended in either Botu-Crio (CryoVital, Grandau, Germany) or INRA 96 containing 2% egg yolk and 2.5% each of methyl- and dimethylformamide (INRA 96), and they were cryopreserved over liquid nitrogen vapor. Thawed samples were incubated in vitro (25 °C) and evaluated for percent total sperm motility, forward progression, and acrosomal integrity at hourly intervals for 4 hours. Spermic ejaculates were obtained from all males, and the mean seminal volume, sperm concentration per milliliter, percent sperm motility, progressive status, and percent morphologically normal cells were 20.4 ± 4.3 mL, 101.2 ± 24.0 × 10(6)/mL, 46.1% ± 5.0%, 2.9 ± 0.1, and 6.9% ± 1.4%, respectively. There was a positive significant correlation between percent normal sperm and animal age (r = 0.66; P tapir; demonstrate that tapir spermatozoa can be cryopreserved in diluents containing amides alone or in combination with glycerol; and provide fundamental information critical for development of assisted reproductive technologies for the Baird's tapir.

Influencia de la disponibilidad de agua en la presencia y abundancia de Tapirus bairdii en la selva de Calakmul, Campeche, México Influence of water availability in the presence and abundance of Tapirus bairdii in the Calakmul forest, Campeche, Mexico

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Sadao Pérez-Cortez

2012-09-01

Full Text Available En 15 aguadas agrupadas en 3 microrregiones (norte, centro y sur y sus alrededores se evaluaron las características ambientales que podrían determinar la presencia y abundancia del tapir (Tapirus bairdii en la Reserva de la Biosfera Calakmul (RBC, Campeche. Entre los años 2008-2010, se registró la presencia del tapir en 14 aguadas con un esfuerzo de muestreo de 3 470 días-trampa, la abundancia fue de 37.57 individuos /1 000 trampas-noche. Los tapires mostraron un patrón de actividad nocturno, la estructura de edad fue dominada por adultos y la proporción de sexos de los individuos fotografiados fue de 1 a 1. La microrregión sur y la aguada 6 (de la microrregión centro tuvieron mayor abundancia. La abundancia, disponibilidad de alimento y agua presentaron variaciones a escala espacial y temporal. La presencia del agua en las aguadas fue determinante para la presencia de tapir, pero las variables ambientales que más influyeron en la abundancia fueron el porcentaje de agua en las aguadas y la dominancia vegetal de acahual arbóreo y selva alta. En la región de Calakmul, las aguadas deben ser una de las prioridades en su conservación.In 15 waterholes (aguadas grouped in 3 micro-regions (North, Central and South and surrounding areas, we evaluated the environmental characteristics that could determine presence and abundance of the tapir (Tapirus bairdii in Calakmul Biosphere Reserve (CBR, Campeche. Tapirs presence were recorded in 14 watering holes between 2008 and 2010, with a sample effort of 3 470 days/camera-trap. The abundance was of 37.57-individuals/1 000 nights traps. Tapirs showed a nocturnal activity pattern and the age structure was dominated by adults with a sex ratio of 1:1. The southern micro-region and the waterhole 6 (central micro-region had highest abundance. Abundance, food and water availability showed spatial and temporal variations. Water presence in waterholes was crucial to the presence of tapirs; the environmental

How do Purple Sandpipers Calidris maritima survive the winter north of the Arctic circle?

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Summers, R.W.; Piersma, T.; Strann, K.B.; Wiersma, P.

1998-01-01

Winter north of the Arctic circle in northern Norway is colder, windier and there is less solar radiation than in eastern Scotland, at a latitude 13 degrees further south. We predicted from equations derived from heated taxidermic mounts that the maintenance metabolism (Basal Metabolic Rate plus

Distribución espacial y temporal de aves playeras (Orden: Charadriiformes en Laguna San Ignacio, Baja California Sur, México Temporal and spatial distribution of shorebirds (Charadriiformes at San Ignacio Lagoon, Baja California Sur, Mexico

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Luis Francisco Mendoza

2013-03-01

monthly censuses (October 2007-September 2008 on the entire internal perimeter of the lagoon, which we divided into four areas: two at the North and two at the South. We observed a seasonal pattern, with the lowest abundance in May (1 585 birds and the highest in October (47 410. The most abundant species were Marbled Godwits (Limosa fedoa; 55% of the total records, Western Sandpipers (Calidris mauri; 23%, and Willet (Tringa semipalmata; 10%. All three species were more abundant in autumn; for both, the Marbled Godwit and Willet, we observed their highest numbers in winter and spring, while the Western Sandpiper showed noticeable oscillations, reaching a maximum in early winter (December. In summer, Marbled Godwit and Willet were the only birds present but in lower numbers. Here present the first records of the Pacific Red Knot (Calidris canutus roselaari in the area. Bird abundance and species richness were influenced seasonally by migration and spatially by sites in the lagoon. The greatest shorebird abundance was in the South area of the lagoon, probably because of better accessibility to food. Our results allowed the inclusion of San Ignacio Lagoon in the Western Hemisphere Shorebirds Reserve Network (WHSRN as a site of international importance

Heterospecific sociality of birds on beaches from southeastern Brazil

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César Cestari

2009-12-01

Full Text Available Studies on the sociality of heterospecific assemblages of birds have promoted a greater understanding of the types of interactions and survivorship between coexisting species. This study verified the group compositions in bird assemblages and analyzed the sociality of migratory and resident species on sandy beaches of southeastern Brazil. A transect was established on the median portion of beaches and all the groups of bird species (monospecific, heterospecific and solitary individuals were registered four days per month from November 2006 to April 2007. The sociality of each species was calculated by its frequency in heterospecific groups, its proportional number of contacts with other species in heterospecific groups, and the number of species that it associated with. Semipalmated Sandpiper Calidris pusilla (Linnaeus, 1766 and Semipalmated Plover Charadrius semipalmatus Bonaparte, 1825 (both migratory had the highest degree of sociality and did not show a preference to associate with either residents or migratory species. Sanderling Calidris alba (Pallas, 1764 (migratory occupied the third position in the sociality rank and associated with migratory species frequently. Southern Caracara Carara plancus (Miller, 1777 and Black Vulture Coragyps atratus (Beschstein, 1793 (both resident were uniquely found among heterospecific groups with necrophagous and resident species. Kelp Gull Larus dominicanus Lichtenstein, 1823 (resident associated more frequently with resident species. The sociality in assemblages of birds may promote advantages such as an increased collective awareness in dangerous situations and indication of sites with abundant food sources.

Ways to be different: Foraging adaptations that facilitate higher intake rates in a northerly wintering shorebird compared with a low-latitude conspecific

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Ruthrauff, Daniel R.; Dekinga, Anne; Gill, Robert E.; van Gils, Jan A.; Piersma, Theunis

2015-01-01

At what phenotypic level do closely related subspecies that live in different environments differ with respect to food detection, ingestion and processing? This question motivated an experimental study on rock sandpipers (Calidris ptilocnemis). The species' nonbreeding range spans 20 deg of latitude, the extremes of which are inhabited by two subspecies: C. p. ptilocnemis that winters primarily in upper Cook Inlet, Alaska (61°N) and C. p. tschuktschorum that overlaps slightly with C. p. ptilocnemis but whose range extends much farther south (∼40°N). In view of the strongly contrasting energetic demands of their distinct nonbreeding distributions, we conducted experiments to assess the behavioral, physiological and sensory aspects of foraging and we used the bivalve Macoma balthica for all trials. C. p. ptilocnemis consumed a wider range of prey sizes, had higher maximum rates of energy intake, processed shell waste at higher maximum rates and handled prey more quickly. Notably, however, the two subspecies did not differ in their abilities to find buried prey. The subspecies were similar in size and had equally sized gizzards, but the more northern ptilocnemis individuals were 10–14% heavier than their same-sex tschuktschorum counterparts. The higher body mass in ptilocnemis probably resulted from hypertrophy of digestive organs (e.g. intestine, liver) related to digestion and nutrient assimilation. Given the previously established equality of the metabolic capacities of the two subspecies, we propose that the high-latitude nonbreeding range of ptilocnemis rock sandpipers is primarily facilitated by digestive (i.e. physiological) aspects of their foraging ecology rather than behavioral or sensory aspects.

Complex postglacial recolonization inferred from population genetic structure of mottled sculpin Cottus bairdii in tributaries of eastern Lake Michigan, U.S.A.

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Homola, J J; Ruetz, C R; Kohler, S L; Thum, R A

2016-11-01

This study used analyses of the genetic structure of a non-game fish species, the mottled sculpin Cottus bairdii to hypothesize probable recolonization routes used by cottids and possibly other Laurentian Great Lakes fishes following glacial recession. Based on samples from 16 small streams in five major Lake Michigan, U.S.A., tributary basins, significant interpopulation differentiation was documented (overall F ST = 0·235). Differentiation was complex, however, with unexpectedly high genetic similarity among basins as well as occasionally strong differentiation within basins, despite relatively close geographic proximity of populations. Genetic dissimilarities were identified between eastern and western populations within river basins, with similarities existing between eastern and western populations across basins. Given such patterns, recolonization is hypothesized to have occurred on three occasions from more than one glacial refugium, with a secondary vicariant event resulting from reduction in the water level of ancestral Lake Michigan. By studying the phylogeography of a small, non-game fish species, this study provides insight into recolonization dynamics of the region that could be difficult to infer from game species that are often broadly dispersed by humans. © 2016 The Fisheries Society of the British Isles.

Improved arrival-date estimates of Arctic-breeding Dunlin (Calidris alpina arcticola)

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Doll, Andrew C.; Lanctot, Richard B.; Stricker, Craig A.; Yezerinac, Stephen M.; Wunder, Michael B.

2015-01-01

The use of stable isotopes in animal ecology depends on accurate descriptions of isotope dynamics within individuals. The prevailing assumption that laboratory-derived isotopic parameters apply to free-living animals is largely untested. We used stable carbon isotopes (δ13C) in whole blood from migratory Dunlin (Calidris alpina arcticola) to estimate an in situ turnover rate and individual diet-switch dates. Our in situ results indicated that turnover rates were higher in free-living birds, in comparison to the results of an experimental study on captive Dunlin and estimates derived from a theoretical allometric model. Diet-switch dates from all 3 methods were then used to estimate arrival dates to the Arctic; arrival dates calculated with the in situ turnover rate were later than those with the other turnover-rate estimates, substantially so in some cases. These later arrival dates matched dates when local snow conditions would have allowed Dunlin to settle, and agreed with anticipated arrival dates of Dunlin tracked with light-level geolocators. Our study presents a novel method for accurately estimating arrival dates for individuals of migratory species in which return dates are difficult to document. This may be particularly appropriate for species in which extrinsic tracking devices cannot easily be employed because of cost, body size, or behavioral constraints, and in habitats that do not allow individuals to be detected easily upon first arrival. Thus, this isotopic method offers an exciting alternative approach to better understand how species may be altering their arrival dates in response to changing climatic conditions.

Factors associated with arrival densities of grasshopper sparrow (Ammodramus savannarum) and baird's sparrow (A. bairdii) in the upper great plains

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Ahlering, M.A.; Johnson, D.H.; Faaborg, John

2009-01-01

Although critical to habitat and population management, the proximate cues that birds use to establish territories are largely unknown. Understanding these cues is important for birds, such as many grassland birds, that exhibit high annual variability in population density and make new habitat-selection decisions annually. Identifying the actual cues used is difficult in the field, but the factors associated with the arrival densities of birds can help uncover variables that are involved in or correlated with cues used for selection. During the summers of 2002–2004, we investigated how weather and local vegetation factors were related to arrival densities of Grasshopper Sparrows (Ammodramus savannarum) and Baird's Sparrows (A. bairdii) at three locations across North Dakota and Saskatchewan. Spring densities of Grasshopper Sparrows were positively correlated with concurrent May precipitation, whereas densities of Baird's Sparrows were negatively correlated with the previous winter's snowfall. We used a model-selection approach to evaluate the vegetation characteristics associated with arrival densities of birds. Grasshopper Sparrow densities showed a strong negative relationship to woody cover, and Baird's Sparrow densities showed a negative relationship to vegetation height and vegetation density near the ground. Our results provide a first detailed look at habitat and weather associations immediately after arrival in spring and an important first step in uncovering factors that may be involved in habitat selection in two grassland species.

Experimental challenge and pathology of highly pathogenic avian influenza virus H5N1 in dunlin (Calidris alpina), an intercontinental migrant shorebird species

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Hall, Jeffrey S.; Franson, J. Christian; Gill, Robert E.; Meteyer, Carol U.; TeSlaa, Joshua L.; Nashold, Sean W.; Dusek, Robert J.; Ip, Hon S.

2011-01-01

Background Shorebirds (Charadriiformes) are considered one of the primary reservoirs of avian influenza. Because these species are highly migratory, there is concern that infected shorebirds may be a mechanism by which highly pathogenic avian influenza virus (HPAIV) H5N1 could be introduced into North America from Asia. Large numbers of dunlin (Calidris alpina) migrate from wintering areas in central and eastern Asia, where HPAIV H5N1 is endemic, across the Bering Sea to breeding areas in Alaska. Low pathogenic avian influenza virus has been previously detected in dunlin, and thus, dunlin represent a potential risk to transport HPAIV to North America. To date no experimental challenge studies have been performed in shorebirds.

Linking sex differences in corticosterone with individual reproductive behaviour and hatch success in two species of uniparental shorebirds.

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Edwards, Darryl B; Chin, Eunice H; Burness, Gary; Gilchrist, H Grant; Schulte-Hostedde, Albrecht I

2013-09-01

In birds, corticosterone (CORT) appears to facilitate reproductive activity because baseline and stress-induced CORT levels are elevated in breeding individuals compared with other times of the year. In particular, CORT is lower in the sex providing most of the parental care (i.e., incubation), which could be an important adaptation to tolerate stressors that result in abandoning reproduction. Therefore, one explanation for sex differences in CORT is that lower levels are favoured during the incubation/parental phase of reproduction. Using two species of uniparental shorebird - polyandrous red phalaropes (Phalaropus fulicarius) and polygynous white-rumped sandpipers (Calidris fuscicollis) - we predicted that the incubating sex would have lower baseline and stress-induced CORT, and incubating individuals with lower CORT would more effectively defend nests against a simulated intrusion, would return more quickly afterwards, and would ultimately have higher hatch success. We found that phalaropes followed the predicted pattern: incubating individuals (males) had lower baseline and stress-induced CORT than females but for baseline CORT these differences existed prior to males commencing incubation. Incubating male phalaropes with lower baseline and stress-induced CORT returned to incubate more quickly after a disturbance and there was non-significant tendency for baseline CORT to be lower in successful nests. In sandpipers, we observed no sex differences and no significant relationships between individual CORT levels and nest defence behaviours or hatch success. Our results demonstrate that in phalaropes at least, selection favours lower baseline and stress-induced CORT during the nesting period. These results can explain sex differences in stress-induced levels of CORT, however sex differences in baseline CORT were present prior to incubation. Copyright © 2013 Elsevier Inc. All rights reserved.

High renesting rates in arctic-breeding Dunlin (Calidris alpina): A clutch-removal experiment

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Gates, H. River; Lanctot, Richard B.; Powell, Abby N.

2013-01-01

The propensity to replace a clutch is a complex component of avian reproduction and poorly understood. We experimentally removed clutches from an Arctic-breeding shorebird, the Dunlin (Calidris alpina arcticola), during early and late stages of incubation to investigate replacement clutch rates, renesting interval, and mate and site fidelity between nesting attempts. In contrast to other Arctic studies, we documented renesting by radiotracking individuals to find replacement clutches. We also examined clutch size and mean egg volume to document changes in individual females’ investment in initial and replacement clutches. Finally, we examined the influence of adult body mass, clutch volume, dates of clutch initiation and nest loss, and year on the propensity to renest. We found high (82–95%) and moderate (35–50%) rates of renesting for early and late incubation treatments. Renesting intervals averaged 4.7–6.8 days and were not different for clutches removed early or late in incubation. Most pairs remained together for renesting attempts. Larger females were more likely to replace a clutch; female body mass was the most important parameter predicting propensity to renest. Clutches lost later in the season were less likely to be replaced. We present evidence that renesting is more common in Arctic-breeding shorebirds than was previously thought, and suggest that renesting is constrained by energetic and temporal factors as well as mate availability. Obtaining rates of renesting in species breeding at different latitudes will help determine when this behavior is likely to occur; such information is necessary for demographic models that include individual and population-level fecundity estimates.

Abundancia relativa, estructura poblacional, preferencia de hábitat y patrones de actividad del tapir centroamericano Tapirus bairdii (Perissodactyla: Tapiridae, en la Selva de Los Chimalapas, Oaxaca, México

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Iván Lira-Torres

2014-12-01

Full Text Available El tapir centroamericano (Tapirus bairdii está en peligro de extinción debido principalmente a la pérdida y fragmentación de su hábitat, y a la cacería sin control en toda su área de distribución. Una de las regiones terrestres prioritarias para la conservación de esta especie en la zona norte de su distribución se encuentra en la Selva de los Chimalapas, Oaxaca. Por lo que el objetivo de la presente investigación fue determinar la abundancia relativa, estructura poblacional, preferencia de hábitat y patrones de actividad del tapir centroamericano (Tapirus bairdii en la Selva de los Chimalapas, Oaxaca, México, mediante el uso de cámaras trampa. Se realizaron cinco periodos de muestreo fotográfico entre 2009 y 2013 con un total de 30 cámaras trampa en cada periodo. El factor de diseño fue la intensidad de caza entre dos sitios. Con un esfuerzo total de muestreo de 9 000 días/trampa se estimó un índice de abundancia relativa (IAR de 6.77/1 000 trampas-noche (n=61, variando significativamente entre estaciones de muestreo (Mann-Whitney, p<0.01. Durante la temporada de secas, los tapires fueron más abundantes y utilizaron con mayor intensidad el bosque tropical perennifolio sin cacería (x², p<0.5. Mientras que en la temporada de lluvia, el bosque tropical perennifolio con cacería y la vegetación secundaria con cacería fueron los hábitat significativamente más utilizados que lo esperado (x², p<0.5. Con respecto a la estructura poblacional se obtuvo un 95.08% de registros fotográficos de animales adultos (n=58. Se registraron tres tipos de patrones de actividad para la especie, siendo el patrón nocturno el que presentó mayor porcentaje de registros; 88.33% (Kruskal-Wallis, p<0.05. Finalmente, con base al número de registros fotográficos y a los resultados obtenidos es posible considerar a la Selva de los Chimalapas como la segunda eco-región terrestre prioritaria en importancia; después de la Selva Maya (Campeche

Intercontinental genetic structure and gene flow in Dunlin (Calidris alpina), a potential vector of avian influenza

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Miller, Mark P.; Haig, Susan M.; Mullins, Thomas D.; Ruan, Luzhang; Casler, Bruce; Dondua, Alexei; Gates, River H.; Johnson, J. Matthew; Kendall, Steven J.; Tomkovich, Pavel S.; Tracy, Diane; Valchuk, Olga P.; Lanctot, Richard B.

2015-01-01

Waterfowl (Anseriformes) and shorebirds (Charadriiformes) are the most common wild vectors of influenza A viruses. Due to their migratory behavior, some may transmit disease over long distances. Migratory connectivity studies can link breeding and nonbreeding grounds while illustrating potential interactions among populations that may spread diseases. We investigated Dunlin (Calidris alpina), a shorebird with a subspecies (C. a. arcticola) that migrates from nonbreeding areas endemic to avian influenza in eastern Asia to breeding grounds in northern Alaska. Using microsatellites and mitochondrial DNA, we illustrate genetic structure among six subspecies: C. a. arcticola, C. a. pacifica, C. a. hudsonia, C. a. sakhalina, C. a. kistchinski, and C. a. actites. We demonstrate that mitochondrial DNA can help distinguish C. a. arcticola on the Asian nonbreeding grounds with >70% accuracy depending on their relative abundance, indicating that genetics can help determine whether C. a. arcticola occurs where they may be exposed to highly pathogenic avian influenza (HPAI) during outbreaks. Our data reveal asymmetric intercontinental gene flow, with some C. a. arcticola short-stopping migration to breed with C. a. pacifica in western Alaska. Because C. a. pacifica migrates along the Pacific Coast of North America, interactions between these subspecies and other taxa provide route for transmission of HPAI into other parts of North America.

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

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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.

Population-level body condition correlates with productivity in an arctic wader, the dunlin Calidris alpina, during post-breeding migration.

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Grzegorz Neubauer

Full Text Available Weather and predation constitute the two main factors affecting the breeding success of those Arctic waders whose productivity is highly variable over the years. We tested whether reproductive success is associated with the post-breeding condition of adults, in which in 'good' years (with warm weather, plentiful food and low predation pressure the condition of breeders and their productivity is high. To verify this hypothesis, we used a 10-year dataset comprising 20,792 dunlins Calidris alpina, trapped during migration at a stopover site on the southern Baltic Sea shore. Males were consistently in a slightly worse condition than females, likely due to male-biased parental investment in brood rearing. Annual productivity indices were positively correlated with the respective condition indices of breeders from the Eurasian Arctic, indicating that in 'good' years, despite great effort spent on reproduction, breeders leave the breeding grounds in better condition. The pattern did not hold for 1992: productivity was low, but the average condition of adults during migration was the highest noted over the decade. We suggest that the delayed effect of the Mount Pinatubo eruption in the Philippines in 1991, could be responsible for the unexpected high condition of Arctic breeders in 1992. High population-level average condition, coupled with the low productivity could stem from severe weather caused by the volcano eruption a year before and strong predation pressure, which in turn lead to a reduced investment in reproduction. The importance of large-scale episodic phenomena, like this volcano eruption, may blur the statistical associations of wildlife with local environmental drivers.

Population-level body condition correlates with productivity in an arctic wader, the dunlin Calidris alpina, during post-breeding migration.

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Neubauer, Grzegorz; Pilacka, Lucyna; Zieliński, Piotr; Gromadzka, Jadwiga

2017-01-01

Weather and predation constitute the two main factors affecting the breeding success of those Arctic waders whose productivity is highly variable over the years. We tested whether reproductive success is associated with the post-breeding condition of adults, in which in 'good' years (with warm weather, plentiful food and low predation pressure) the condition of breeders and their productivity is high. To verify this hypothesis, we used a 10-year dataset comprising 20,792 dunlins Calidris alpina, trapped during migration at a stopover site on the southern Baltic Sea shore. Males were consistently in a slightly worse condition than females, likely due to male-biased parental investment in brood rearing. Annual productivity indices were positively correlated with the respective condition indices of breeders from the Eurasian Arctic, indicating that in 'good' years, despite great effort spent on reproduction, breeders leave the breeding grounds in better condition. The pattern did not hold for 1992: productivity was low, but the average condition of adults during migration was the highest noted over the decade. We suggest that the delayed effect of the Mount Pinatubo eruption in the Philippines in 1991, could be responsible for the unexpected high condition of Arctic breeders in 1992. High population-level average condition, coupled with the low productivity could stem from severe weather caused by the volcano eruption a year before and strong predation pressure, which in turn lead to a reduced investment in reproduction. The importance of large-scale episodic phenomena, like this volcano eruption, may blur the statistical associations of wildlife with local environmental drivers.

Using the North American Breeding Bird Survey to assess broad-scale response of the continent's most imperiled avian community, grassland birds, to weather variability

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Gorzo, Jessica; Pidgeon, Anna M.; Thogmartin, Wayne E.; Allstadt, Andrew J.; Radeloff, Volker C.; Heglund, Patricia J.; Vavrus, Stephen J.

2016-01-01

Avian populations can respond dramatically to extreme weather such as droughts and heat waves, yet patterns of response to weather at broad scales remain largely unknown. Our goal was to evaluate annual variation in abundance of 14 grassland bird species breeding in the northern mixed-grass prairie in relation to annual variation in precipitation and temperature. We modeled avian abundance during the breeding season using North American Breeding Bird Survey (BBS) data for the U.S. Badlands and Prairies Bird Conservation Region (BCR 17) from 1980 to 2012. We used hierarchical Bayesian methods to fit models and estimate the candidate weather parameters standardized precipitation index (SPI) and standardized temperature index (STI) for the same year and the previous year. Upland Sandpiper (Bartramia longicauda) responded positively to within-year STI (β = 0.101), and Baird's Sparrow (Ammodramus bairdii) responded negatively to within-year STI (β = −0.161) and positively to within-year SPI (β = 0.195). The parameter estimates were superficially similar (STI β = −0.075, SPI β = 0.11) for Grasshopper Sparrow (Ammodramus savannarum), but the best-selected model included an interaction between SPI and STI. The best model for both Eastern Kingbird (Tyrannus tyrannus) and Vesper Sparrow (Pooecetes gramineus) included the additive effects of within-year SPI (β = −0.032 and β = −0.054, respectively) and the previous-year's SPI (β = −0.057 and −0.02, respectively), although for Vesper Sparrow the lag effect was insignificant. With projected warmer, drier weather during summer in the Badlands and Prairies BCR, Baird's and Grasshopper sparrows may be especially threatened by future climate change.

Migration ecology and stopover population size of Red Knots Calidris canutus rufa at Mingan Archipelago after exiting the breeding grounds

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Lyons, James E.; Baker, Allan J.; González, Patricia M.; Aubry, Yves; Buidin, Christophe; Rochepault, Yann

2018-01-01

Populations of migratory birds present unique conservation challenges given the often vast distances separating critical resources throughout the annual cycle. Migration areas close to the breeding grounds represent a link between two key stages of the annual cycle, and understanding migration ecology as birds exit the breeding grounds may be particularly informative for successful conservation. We studied migration phenology and stopover ecology of an endangered subspecies of the Red Knot Calidris canutus rufa at a migration area relatively close to its breeding range. Using mark-recapture/resight data and a Jolly-Seber model for open populations, we described the arrival and departure schedules, stopover duration, and passage population size at the Mingan Archipelago, Quebec, Canada. Red Knots arrived at the study area in two distinct waves of birds separated by approximately 22 days. Nearly 30% of the passage population arrived in the first wave of arrivals during 15–18 July, and approximately 22% arrived in a second wave during 8–11 August. The sex-ratio in the stopover population at the time of the first wave was slightly skewed toward females, whereas the second wave was heavily skewed toward males. Because males remain on the breeding grounds to care for young, this may reflect successfulbreeding in the year of our study. The estimated stopover duration (population mean) was 11 days (95% credible interval: 10.3–11.7 days), but stopover persistence was variable throughout the season. We estimated a passage population size of 9,450 birds (8,355–10,710), a minimum estimate for reasons related to the duration of our sampling. Mingan Archipelago is thus an important migration area for this endangered subspecies and could be a priority in conservation planning. Our results also emphasize the advantages of mark-recapture/resight approaches for estimating migration phenology and stopover persistence.

Collaborative approaches to the evolution of migration and the development of science-based conservation in shorebirds

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Harrington, Brian A.; Brown, S.; Corven, James; Bart, Jonathan

2002-01-01

Shorebirds are among the most highly migratory creatures on earth. Both the study of their ecology and ongoing efforts to conserve their populations must reflect this central aspect of their biology. Many species of shorebirds use migration and staging sites scattered throughout the hemisphere to complete their annual migrations between breeding areas and nonbreeding habitats (Morrison 1984). The vast distances between habitats they use pose significant challenges for studying their migration ecology. At the same time, the large number of political boundaries shorebirds cross during their epic migrations create parallel challenges for organizations working on their management and conservation.Nebel et al. (2002) represent a collaborative effort to understand the conservation implications of Western Sandpiper (Calidris mauri) migration ecology on a scale worthy of this highly migratory species. The data sets involved in the analysis come from four U.S. states, two Canadian provinces, and a total of five nations. Only by collaborating on this historic scale were the authors able to assemble the information necessary to understand important aspects of the migration ecology of this species, and the implications for conservation of the patterns they discovered.Collaborative approaches to shorebird migration ecology developed slowly over several decades. The same period also saw the creation of large-scale efforts to monitor and conserve shorebirds. This overview first traces the history of the study of migration ecology of shorebirds during that fertile period, and then describes the monitoring and protection efforts that have been developed in an attempt to address the enormous issues of scale posed by shorebird migration ecology and conservation.

Habitat use by Red Knots (Calidris canutus rufa): Experiments with oyster racks and reefs on the beach and intertidal of Delaware Bay, New Jersey

Science.gov (United States)

Burger, Joanna; Niles, Lawrence J.

2017-07-01

Sea level rise and increasing human activities have decreased intertidal habitat in many places in the world. The expansion of aquaculture in intertidal areas may impact birds and other organisms using these habitats, leading to questions of sustainability of both aquaculture and functioning estuarine ecosystems. Understanding the effect of oyster culture on shorebird activity, particularly on Red Knots (Calidris canutus rufa), a species on the U.S. Threatened List, is important for adaptive management and the expansion of oyster culture. In May 2013 we experimentally compared Red Knot and shorebird use of a beach section with racks and a control, and in 2016 we compared the use of sections with artificial reefs, oyster racks, and control on Delaware Bay, New Jersey (USA). The data included only times when no workers or other people were present. Censuses, conducted every 30 min throughout the day (279 censuses in 2013, 231 censuses in 2016), included the number of Red Knots and other shorebirds in each treatment section. In 2013, the total number of shorebirds was significantly higher in the rack section than in the control section, except for Red Knots and Ruddy Turnstones (Arenaria interpres) that occurred in higher numbers in the control than in the rack section. In 2016 Red Knot numbers were also significantly lower in the rack section. In 2013, the mean number of Red Knots/census was 13 for racks vs 59 for the control (P racks and over 68 for other treatments (P racks while both foraging and roosting, suggesting that caution should be used before placing oyster racks in areas used for foraging by Red Knots.

Experimental challenge and pathology of highly pathogenic avian influenza virus H5N1 in dunlin (Calidris alpina), an intercontinental migrant shorebird species.

Science.gov (United States)

Hall, Jeffrey S; Franson, J Christian; Gill, Robert E; Meteyer, Carol U; TeSlaa, Joshua L; Nashold, Sean; Dusek, Robert J; Ip, Hon S

2011-09-01

Shorebirds (Charadriiformes) are considered one of the primary reservoirs of avian influenza. Because these species are highly migratory, there is concern that infected shorebirds may be a mechanism by which highly pathogenic avian influenza virus (HPAIV) H5N1 could be introduced into North America from Asia. Large numbers of dunlin (Calidris alpina) migrate from wintering areas in central and eastern Asia, where HPAIV H5N1 is endemic, across the Bering Sea to breeding areas in Alaska. Low pathogenic avian influenza virus has been previously detected in dunlin, and thus, dunlin represent a potential risk to transport HPAIV to North America. To date no experimental challenge studies have been performed in shorebirds. Wild dunlin were inoculated intranasally and intrachoanally various doses of HPAIV H5N1. The birds were monitored daily for virus excretion, disease signs, morbidity, and mortality. The infectious dose of HPAIV H5N1 in dunlin was determined to be 10(1.7) EID(50)/100 μl and that the lethal dose was 10(1.83) EID(50)/100 μl. Clinical signs were consistent with neurotropic disease, and histochemical analyses revealed that infection was systemic with viral antigen and RNA most consistently found in brain tissues. Infected birds excreted relatively large amounts of virus orally (10(4) EID(50)) and smaller amounts cloacally. Dunlin are highly susceptible to infection with HPAIV H5N1. They become infected after exposure to relatively small doses of the virus and if they become infected, they are most likely to suffer mortality within 3-5 days. These results have important implications regarding the risks of transport and transmission of HPAIV H5N1 to North America by this species and raises questions for further investigation. Published 2011. This article is a US Government work and is in the public domain in the USA.

Prey type and foraging ecology of Sanderlings Calidris alba in different climate zones: are tropical areas more favourable than temperate sites?

Directory of Open Access Journals (Sweden)

Kirsten Grond

2015-08-01

Full Text Available Sanderlings (Calidris alba are long-distance migratory shorebirds with a non-breeding range that spans temperate and tropical coastal habitats. Breeding in the High Arctic combined with non-breeding seasons in the tropics necessitate long migrations, which are energetically demanding. On an annual basis, the higher energy expenditures during migration might pay off if food availability in the tropics is higher than at temperate latitudes. We compared foraging behaviour of birds at a north temperate and a tropical non-breeding site in the Netherlands and Ghana, respectively. In both cases the birds used similar habitats (open beaches, and experienced similar periods of daylight, which enabled us to compare food abundance and availability, and behavioural time budgets and food intake. During the non-breeding season, Sanderlings in the Netherlands spent 79% of their day foraging; in Ghana birds spent only 38% of the daytime period foraging and the largest proportion of their time resting (58%. The main prey item in the Netherlands was the soft-bodied polychaete Scolelepis squamata, while Sanderlings in Ghana fed almost exclusively on the bivalve Donax pulchellus, which they swallowed whole and crushed internally. Average availability of polychaete worms in the Netherlands was 7.4 g ash free dry mass (AFDM m−2, which was one tenth of the 77.1 g AFDM m−2 estimated for the beach in Ghana. In the tropical environment of Ghana the Sanderlings combined relatively low energy requirements with high prey intake rates (1.64 mg opposed to 0.13 mg AFDM s−1 for Ghana and the Netherlands respectively. Although this may suggest that the Ghana beaches are the most favourable environment, processing the hard-shelled bivalve (D. pulchellus which is the staple food could be costly. The large amount of daytime spent resting in Ghana may be indicative of the time needed to process the shell fragments, rather than indicate rest.

Population variation in isotopic composition of shorebird feathers: Implications for determining molting grounds

Science.gov (United States)

Torres-Dowdall, J.; Farmer, A.H.; Bucher, E.H.; Rye, R.O.; Landis, G.

2009-01-01

Stable isotope analyses have revolutionized the study of migratory connectivity. However, as with all tools, their limitations must be understood in order to derive the maximum benefit of a particular application. The goal of this study was to evaluate the efficacy of stable isotopes of C, N, H, O and S for assigning known-origin feathers to the molting sites of migrant shorebird species wintering and breeding in Argentina. Specific objectives were to: 1) compare the efficacy of the technique for studying shorebird species with different migration patterns, life histories and habitat-use patterns; 2) evaluate the grouping of species with similar migration and habitat use patterns in a single analysis to potentially improve prediction accuracy; and 3) evaluate the potential gains in prediction accuracy that might be achieved from using multiple stable isotopes. The efficacy of stable isotope ratios to determine origin was found to vary with species. While one species (White-rumped Sandpiper, Calidris fuscicollis) had high levels of accuracy assigning samples to known origin (91% of samples correctly assigned), another (Collared Plover, Charadrius collaris) showed low levels of accuracy (52% of samples correctly assigned). Intra-individual variability may account for this difference in efficacy. The prediction model for three species with similar migration and habitat-use patterns performed poorly compared with the model for just one of the species (71% versus 91% of samples correctly assigned). Thus, combining multiple sympatric species may not improve model prediction accuracy. Increasing the number of stable isotopes in the analyses increased the accuracy of assigning shorebirds to their molting origin, but the best combination - involving a subset of all the isotopes analyzed - varied among species.

Change in numbers of resident and migratory shorebirds at the Cabo Rojo Salt Flats, Puerto Rico, USA (1985–2014)

Science.gov (United States)

Parks, Morgan A.; Collazo, Jaime A.; Colon, Jose A.; Ramos Alvarez, Katsi R.; Diaz, Oscar

2016-01-01

North American migratory shorebirds have declined markedly since the 1980s, underscoring the importance of population surveys to conduct status and trend assessments. Shorebird surveys were conducted during three multi-year periods between 1985 and 2014 and used to assess changes in numbers and species composition at the Cabo Rojo Salt Flats, Puerto Rico, USA, a site of regional importance in the eastern Caribbean. Eight fewer species (total = 21) were recorded in 2013–2014 as compared to the 29 from 1985–1992; all eight species were Nearctic migrants. Small calidrids had the highest population counts; however, this suite of species and all others experienced a ≥ 70% decline. Combined counts from the salt flats and neighboring wetlands in 2013–2014 were lower than counts only from the Cabo Rojo Salt Flats in two previous multi-year survey periods, which indicated a real change in numbers not just a shift in wetland use. Invertebrate prey density was lower in 2013–2014 than in 1994. Body fat condition of Semipalmated Sandpipers (Calidris pusilla), an index of habitat quality, did not differ between 1985–1992 and 2013–2014. These findings do not exclude the possibility that other species might be affected by lower prey density, or that local declines in numbers reflect changes at hemispheric, not local, scales. The magnitude of change between local and hemispheric scales closely matched for some species. Continued monitoring at the salt flats is warranted to help gauge the status of shorebirds in Puerto Rico and discern the probable cause of declines. Monitoring other sites in the Caribbean is needed for stronger inferences about regional status and trends.

First records of the ticks Amblyomma calcaratum and A. pacae (Acari: Ixodidae parasitizing mammals of Mexico Primeros registros de las garrapatas Amblyomma calcaratum y A. pacae (Acari: Ixodidae parasitando mamíferos de México

Directory of Open Access Journals (Sweden)

Carmen Guzmán-Cornejo

2006-06-01

Full Text Available Based on study of ticks deposited in the Colección Nacional de Ácaros, Instituto de Biología, Universidad Nacional Autónoma de México, we report the first records in Mexico for two species of Amblyomma: Amblyomma calcaratum ex Tamandua mexicana, and Amblyomma pacae ex Tapirus bairdii. These new records increase the number of species recorded for the genus Amblyomma in Mexico to 26.Basado en la revisión de garrapatas depositadas en la Colección Nacional de Ácaros, Instituto de Biología, Universidad Nacional Autónoma de México, establecemos los primeros registros en México para 2 especies del género Amblyomma: Amblyomma calcaratum ex Tamandua mexicana y Amblyomma pacae ex Tapirus bairdii. Estos nuevos registros incrementan a 26 el número de especies del género Amblyomma distribuidas en México.

Efecto de las actividades humanas sobre la diversidad de mamíferos terrestres en un gradiente altitudinal

Directory of Open Access Journals (Sweden)

Lilliana Piedra C

2000-03-01

Full Text Available The effect of human activity on terrestrial mammals was studied with footprint counts in Guanacaste, Costa Rica (10°30'N, 85°40'W in February 1998 (in fifty 2 m² quadrats. The most common species were Canis latrans, Didelphis marsupialis, Odoicoleus virginianus, Dasyprocta punctata and Tapirus bairdii. No stastically significant association was found between humna activity and mammal frequency in the footprint counts.

75 FR 9281 - General Provisions; Revised List of Migratory Birds

Science.gov (United States)

2010-03-01

...); Actitis hypoleucos (Common Sandpiper) is listed as Tringa hypoleucos (J & R); Aethia psittacula (Parakeet Auklet) is listed as Cyclorrhynchus psittacula (R); Anas americana (American Wigeon) is listed as Mareca... Cuculus optatus (AOU 2006); Cyclorrhynchus psittacula (Parakeet Auklet) becomes Aethia psittacula (AOU...

Do Uniparental Sanderlings

NARCIS (Netherlands)

Reneerkens, J.; Grond, K.; Schekkerman, H.; Tulp, I.; Piersma, T.

2011-01-01

Birds breeding in cold environments regularly have to interrupt incubation to forage, causing a trade-off between two mutually exclusive behaviours. Earlier studies showed that uniparental Arctic sandpipers overall spend less time incubating their eggs than biparental species, but interspecific

Seasonal age differences in weight and biometrics of migratory ...

African Journals Online (AJOL)

Calidris alpina) caught in Eilat, Israel, before and after they accomplish the crossing of the combined ecological barrier of the Sinai, Sahara and Sahel deserts. Between 1999–2001, a total of 410 adults and 342 juveniles were banded.

Ambient temperature does not affect fuelling rate in absence of digestive constraints in long-distance migrant shorebird fuelling up in captivity

NARCIS (Netherlands)

Petit, Magali; Vezina, Francois; Piersma, Theunis; Heldmaier, G.

Pre-flight fuelling rates in free-living red knots Calidris canutus, a specialized long-distance migrating shorebird species, are positively correlated with latitude and negatively with temperature. The single published hypothesis to explain these relationships is the heat load hypothesis that

Long-term decreases of corticosterone in captive migrant shorebirds that maintain seasonal mass and moult cycles

NARCIS (Netherlands)

Piersma, T; Ramenofsky, M

Two flocks of Red Knots Calidris canutus, belonging to the temperate-wintering subspecies islandica and to the tropical-wintering subspecies canutus, were kept in outdoor cages at north-temperate latitudes over two annual cycles during which their plasma concentrations of corticosterone were

Economic design in a long-distance migrating molluscivore: how fast-fuelling red knots in Bohai Bay, China, get away with small gizzards

NARCIS (Netherlands)

Yang, H.-Y.; Ma, Z.-J.; Hua, N.; van Gils, J.A.; Zhang, Z.-W.; Piersma, T.

2013-01-01

We carried out an observational and experimental study to decipher how resource characteristics, in interaction with the predator's phenotype, constrain a fitness-determining performance measure, i.e. refuelling in a migrant bird. Two subspecies of red knot (Calidris canutus rogersi and C. c.

Effects of Microhabitat, Flocking, Climate and Migratory Goal on Energy Expenditure in the Annual Cycle of Red Knots

NARCIS (Netherlands)

Wiersma, Popko; Piersma, Theunis

We quantify seasonal changes in the maintenance energy requirements of Red Knots (Calidris canutus islandica). This subspecies breeds on the tundra of northeast Canada and north Greenland, migrates through Iceland and spends the winter in the coastal regions of western Europe. Maintenance Metabolism

Being at the right time at the right place: interpreting the annual life cycle of Afro-Siberian red knots

NARCIS (Netherlands)

Leyrer, J.

2011-01-01

This thesis describes the possible selection pressures acting on survival and, indirectly, on reproduction of Afro-Siberian red knots Calidris canutus canutus while wintering and migrating. Afro-Siberian red knots are long-distance migrants. They travel between the West African wintering areas and

Mechanisms promoting higher growth rate in arctic than in temperate shorebirds

NARCIS (Netherlands)

Schekkerman, H.; Tulp, I.Y.M.; Piersma, T.; Visser, G.H.

2003-01-01

We compared prefledging growth, energy expenditure, and time budgets in the arctic-breeding red knot (Calidris canutus) to those in temperate shorebirds, to investigate how arctic chicks achieve a high growth rate despite energetic difficulties associated with precocial development in a cold

Prey type and foraging ecology of Sanderlings

NARCIS (Netherlands)

Grond, K.; Ntiamoa-Baidu, Y.; Piersma, T.; Reneerkens, J.

2015-01-01

Sanderlings (Calidris alba) are long-distance migratory shorebirds with a non-breeding range that spans temperate and tropical coastal habitats. Breeding in the High Arctic combined with non-breeding seasons in the tropics necessitate long migrations, which are energetically demanding. On an annual

Mechanisms promoting higher growth rate in arctic than in temperate shorebirds

NARCIS (Netherlands)

Schekkerman, H; Tulp, Ingrid; Piersma, T.; Visser, G.H.

We compared prefledging growth, energy expenditure, and time budgets in the arctic-breeding red knot (Calidris canutus) to those in temperate shorebirds, to investigate how arctic chicks achieve a high growth rate despite energetic difficulties associated with precocial development in a cold

Estimates of soil ingestion by wildlife

Science.gov (United States)

Beyer, W.N.; Connor, E.E.; Gerould, S.

1994-01-01

Many wildlife species ingest soil while feeding, but ingestion rates are known for only a few species. Knowing ingestion rates may be important for studies of environmental contaminants. Wildlife may ingest soil deliberately, or incidentally, when they ingest soil-laden forage or animals that contain soil. We fed white-footed mice (Peromyscus leucopus) diets containing 0-15% soil to relate the dietary soil content to the acid-insoluble ash content of scat collected from the mice. The relation was described by an equation that required estimates of the percent acid-insoluble ash content of the diet, digestibility of the diet, and mineral content of soil. We collected scat from 28 wildlife species by capturing animals, searching appropriate habitats for scat, or removing material from the intestines of animals collected for other purposes. We measured the acid-insoluble ash content of the scat and estimated the soil content of the diets by using the soil-ingestion equation. Soil ingestion estimates should be considered only approximate because they depend on estimated rather than measured digestibility values and because animals collected from local populations at one time of the year may not represent the species as a whole. Sandpipers (Calidris spp.), which probe or peck for invertebrates in mud or shallow water, consumed sediments at a rate of 7-30% of their diets. Nine-banded armadillo (Dasypus novemcinctus, soil = 17% of diet), American woodcock (Scolopax minor, 10%), and raccoon (Procyon lotor, 9%) had high rates of soil ingestion, presumably because they ate soil organisms. Bison (Bison bison, 7%), black-tailed prairie dog (Cynomys ludovicianus, 8%), and Canada geese (Branta canadensis, 8%) consumed soil at the highest rates among the herbivores studied, and various browsers studied consumed little soil. Box turtle (Terrapene carolina, 4%), opossum (Didelphis virginiana, 5%), red fox (Vulpes vulpes, 3%), and wild turkey (Meleagris gallopavo, 9%) consumed soil

Influence of human development and predators on nest survival of tundra birds, Arctic Coastal Plain, Alaska.

Science.gov (United States)

Liebezeit, J R; Kendall, S J; Brown, S; Johnson, C B; Martin, P; McDonald, T L; Payer, D C; Rea, C L; Streever, B; Wildman, A M; Zack, S

2009-09-01

Nest predation may influence population dynamics of birds on the Arctic Coastal Plain (ACP) of Alaska, USA. Anthropogenic development on the ACP is increasing, which may attract nest predators by providing artificial sources of food, perches, den sites, and nest sites. Enhanced populations or concentrations of human-subsidized predators may reduce nest survival for tundra-nesting birds. In this study, we tested the hypothesis that nest survival decreases in proximity to human infrastructure. We monitored 1257 nests of 13 shorebird species and 619 nests of four passerine species at seven sites on the ACP from 2002 to 2005. Study sites were chosen to represent a range of distances to infrastructure from 100 m to 80 km. We used Cox proportional hazards regression models to evaluate the effects of background (i.e., natural) factors and infrastructure on nest survival. We documented high spatial and temporal variability in nest survival, and site and year were both included in the best background model. We did not detect an effect of human infrastructure on nest survival for shorebirds as a group. In contrast, we found evidence that risk of predation for passerine nests increased within 5 km of infrastructure. This finding provides quantitative evidence of a relationship between infrastructure and nest survival for breeding passerines on the ACP. A posteriori finer-scale analyses (within oil field sites and individual species) suggested that Red and Red-necked Phalaropes combined (Phalaropus fulicarius, P. lobatus) had lower productivity closer to infrastructure and in areas with higher abundance of subsidized predators. However, we did not detect such a relationship between infrastructure and nest survival for Semipalmated and Pectoral Sandpipers (Calidris pusilla, C. melanotos), the two most abundant shorebirds. High variability in environmental conditions, nest survival, and predator numbers between sites and years may have contributed to these inconsistent results

Raptor predation on wintering Dunlins in relation to the tidal cycle

NARCIS (Netherlands)

Dekker, D.; Ydenberg, R.C.

2004-01-01

At Boundary Bay, British Columbia, Canada, Peregrine Falcons (Falco peregrinus) captured 94 Dunlins (Calidris alpina) in 652 hunts. The two main hunting methods were open attacks on flying Dunlins (62%) and stealth attacks on roosting or foraging Dunlins (35%). Peregrines hunted throughout the day,

Mitochondrial DNA sequence evolution in shorebird populations

NARCIS (Netherlands)

Wenink, P.W.

1994-01-01

This thesis describes the global molecular population structure of two shorebird species, in particular of the dunlin, Calidris alpina, by means of comparative sequence analysis of the most variable part of the mitochondrial DNA (mtDNA) genome. There are several reasons

Body-building without power training : Endogenously regulated pectoral muscle hypertrophy in confined shorebirds

NARCIS (Netherlands)

Dietz, MW; Piersma, T; Dekinga, A

1999-01-01

Shorebirds such as red knots Calidris canutus routinely make migratory flights of 3000 km or more. Previous studies on this species, based on compositional analyses, suggest extensive pectoral muscle hypertrophy in addition to fat storage before take-off. Such hypertrophy could be due to power

Rapid population decline in red knots : fitness consequences of decreased refuelling rates and late arrival in Delaware Bay

NARCIS (Netherlands)

Baker, AJ; Gonzalez, PM; Piersma, T; Niles, LJ; do Nascimento, IDS; Atkinson, PW; Clark, NA; Minton, CDT; Peck, MK; Aarts, G

2004-01-01

Most populations of migrant shorebirds around the world are in serious decline, suggesting that vital condition-dependent rates such as fecundity and annual survival are being affected globally. A striking example is the red knot (Calidris canutus rufa) population wintering in Tierra del Fuego,

Foraging conditions 'at the end of the world' in the context of long-distance migration and population declines in red knots

NARCIS (Netherlands)

Escudero, Graciela; Navedo, Juan G.; Piersma, Theunis; De Goeij, Petra; Edelaar, Pim

The long-distance migrant red knot (Calidris canutus ssp. rufa Scolopacidae) alternates between the northern and southern ends of the New World, one of the longest yearly migrations of any bird and paradoxically overflying apparently suitable habitat at lower latitudes. This subspecies is sharply

Foraging conditions 'at the end of the world' in the context of long-distance migration and population declines in red knots

NARCIS (Netherlands)

Escudero, G.; Navedo, J.G.; Piersma, T.; de Goeij, P.; Edelaar, P.

2012-01-01

The long-distance migrant red knot (Calidris canutus ssp. rufa Scolopacidae) alternates between the northern and southern ends of the New World, one of the longest yearly migrations of any bird and paradoxically overflying apparently suitable habitat at lower latitudes. This subspecies is sharply

Long flights do not influence immune responses of a long-distance migrant bird : a wind-tunnel experiment

NARCIS (Netherlands)

Hasselquist, Dennis; Lindstrom, Ake; Jenni-Eiermann, Susi; Koolhaas, Anita; Piersma, Theunis; Lindström, Åke

2007-01-01

Heavy physical work can result in physiological stress and suppressed immune function. Accordingly, long-distance migrant birds that fly for thousands of km within days can be expected to show immunosuppression, and hence be more vulnerable to infections en route. The red knot Calidris canutus

Winter body mass and over-ocean flocking as components of danger management by Pacific dunlins

NARCIS (Netherlands)

Ydenberg, R.C.; Dekker, D.; Kaiser, G.; Shepherd, P.C.F.; Ogden, L.E.; Rickards, K.; Lank, D.B.

2010-01-01

Background: We compared records of the body mass and roosting behavior of Pacific dunlins (Calidris alpina pacifica) wintering on the Fraser River estuary in southwest British Columbia between the 1970s and the 1990s. 'Over-ocean flocking' is a relatively safe but energetically-expensive alternative

Cost-benefit analysis of mollusc eating in a shorebird I : Foraging and processing costs estimated by the doubly labelled water method

NARCIS (Netherlands)

Piersma, T; Dekinga, A; van Gils, JA; Achterkamp, B; Visser, GH

2003-01-01

Although the energy costs of foraging and food processing in vertebrates may be considerable, they have rarely been quantified separately. Here we present estimates for both cost factors based on a series of trials with a shorebird, the red knot Calidris canutus, fed natural and artificial prey

Basal metabolic rate declines during long-distance migratory flight in great knots

NARCIS (Netherlands)

Battley, PF; Dekinga, A; Dietz, MW; Piersma, T; Tang, SX; Hulsman, K; Battley, Phil F.; Tang, Sixian

2001-01-01

Great Knots (Calidris tenuirostris) make one of the longest migratory flights in the avian world, flying almost 5500 km from Australia to China during northward migration. We measured basal metabolic rate (BMR) and body composition in birds before and after this flight and found that BMR decreased

76 FR 25704 - Announcement of Funding Awards for the Emergency Capital Repair Grant Program; Fiscal Year 2010

Science.gov (United States)

2011-05-05

.... Four Freedoms House of Seattle.. Four Freedoms House of Seattle WA 302 431,113 Replace the brick canopy...,114 Repair the elevators and replace the windows, cooling chassis units in the through-wall... Castle......... PA 128 294,265 Replace the roof and grinder pump. Sandpiper Run National Church Ft. Myers...

Rapid changes in the size of different functional organ and muscle groups during refueling in a long-distance migrating shorebird

NARCIS (Netherlands)

Piersma, T; Gudmundsson, GA; Lilliendahl, K; Gudmundsson, Gudmundur A.

1999-01-01

The adaptive value of size changes in different organ and muscle groups was studied in red knots (Calidris canutus islandica) in relation to their migration. Birds were sampled on five occasions: at arrival in Iceland in May 1994, two times during subsequent refueling, at departure toward, and on

Baseline corticosterone peaks in shorebirds with maximal energy stores for migration : A general preparatory mechanism for rapid behavioral and metabolic transitions?

NARCIS (Netherlands)

Piersma, T; Reneerkens, J; Ramenofsky, M

2000-01-01

In captive red knots (Calidris canutus, Scolopacidae) showing a regulated body mass increase of 50% related to their migration from temperate staging sites to tundra:breeding grounds, plasma corticosterone concentrations increased from less than 10 ng.ml(-1) to levels as high-as 30 ng.ml(-1) when

Seasonal mortality and sequential density dependence in a migratory bird

NARCIS (Netherlands)

Rakhimberdiev, Eldar; van den Hout, Piet J.; Brugge, Maarten; Spaans, Bernard; Piersma, Theunis

2015-01-01

Migratory bird populations may be limited during one or more seasons, and thus at one or more places, but there is a dearth of empirical examples of this possibility. We analyse seasonal survival in a migratory shellfish-eating shorebird (red knot Calidris canutus islandica) during a series of years

Fuelling and moult in Red Knots before northward departure: a visual evaluation of differences between ages, sexes and subspecies

NARCIS (Netherlands)

Verhoeven, M.A.; Van Eerbeek, J.; Hassell, C.J.; Piersma, T.

2016-01-01

The departure of migratory birds from their non-breeding grounds is thought to be driven by the phenologyof their breeding destination. In north-west Australia, two plumage morphs of Red Knot (Calidris canutus) prepare for a5500-km journey to Yellow Sea staging areas. These morphs are recognised as

Fuel use and metabolic response to endurance exercise : a wind tunnel study of a long-distance migrant shorebird

NARCIS (Netherlands)

Jenni-Eiermann, Susanne; Jenni, Lukas; Kvist, Anders; Lindström, Åke; Piersma, Theunis; Visser, G. Henk

This study examines fuel use and metabolism in a group of long-distance migrating birds, red knots Calidris canutus (Scolopacidae), flying under controlled conditions in a wind tunnel for up to 10 h. Data are compared with values for resting birds fasting for the same time. Plasma levels of free

Interference from adults forces young red knots to forage for longer and in dangerous places

NARCIS (Netherlands)

van den Hout, P.J.; van Gils, J.A.; Robin, F.; van der Geest, M.; Dekinga, A.; Piersma, T.

2014-01-01

In birds and mammals, juvenile and adult foragers are often found apart from each other. In this study, we found this is also true for red knots, Calidris canutus canutus, wintering on the intertidal flats of Banc d'Arguin, Mauritania. Not only did juveniles feed separately from adults, they also

Ingested water equilibrates isotopically with the body water pool of a shorebird with unrivaled water fluxes

NARCIS (Netherlands)

Visser, G.H.; Dekinga, A; Achterkamp, B.; Piersma, T.

We investigated the applicability of H-2 to measure the amount of body water (TBW) and water fluxes in relation to diet type and level of food intake in a mollusk-eating shorebird, the Red Knot (Calidris canutus). Six birds were exposed to eight experimental indoor conditions. Average fractional H-2

Does climate change explain the decline of a trans-Saharan Afro-Palaearctic migrant?

Science.gov (United States)

Pearce-Higgins, J W; Yalden, D W; Dougall, T W; Beale, C M

2009-03-01

There is an urgent need to understand how climate change will impact on demographic parameters of vulnerable species. Migrants are regarded as particularly vulnerable to climate change; phenological mismatch has resulted in the local decline of one passerine, whilst variations in the survival of others have been related to African weather conditions. However, there have been few demographic studies on trans-Saharan non-passerine migrants, despite these showing stronger declines across Europe than passerines. We therefore analyse the effects of climate on the survival and productivity of common sandpipers Actitis hypoleucos, a declining non-passerine long-distant migrant using 28 years' data from the Peak District, England. Adult survival rates were significantly negatively correlated with winter North Atlantic Oscillation (NAO), being lower when winters were warm and wet in western Europe and cool and dry in northwest Africa. Annual variation in the productivity of the population was positively correlated with June temperature, but not with an index of phenological mismatch. The 59% population decline appears largely to have been driven by reductions in adult survival, with local productivity poorly correlated with subsequent population change, suggesting a low degree of natal philopatry. Winter NAO was not significantly correlated with adult survival rates in a second, Scottish Borders population, studied for 12 years. Variation in climatic conditions alone does not therefore appear to be responsible for common sandpiper declines. Unlike some passerine migrants, there was no evidence for climate-driven reductions in productivity, although the apparent importance of immigration in determining local recruitment complicates the assessment of productivity effects. We suggest that further studies to diagnose common sandpiper declines should focus on changes in the condition of migratory stop-over or wintering locations. Where possible, these analyses should be repeated

[Distribution of aquatic birds in oxidation lagoons of La Paz city in South Baja California, Mexico].

Science.gov (United States)

Zamora-Orozco, Elvia Margarita; Carmona, Roberto; Brabata, Georgina

2007-06-01

Taxonomic composition, spatial and temporal distribution of aquatic birds in oxidation lagoons (LO) of La Paz city in south Baja California, Mexico, were determined during 24 censuses realized in two-week intervals (April/98-March/99). There are five lagoons of5 Ha each and 17 ha of terrains constantly flooded that serve as feeding areas for cattle and birds. One hundred twenty three species were observed, 75 of which were aquatic birds. A total of 46 041 observations were made (average 1 918 birds/census). Richness and abundance of aquatic birds were influenced mainly by migration of anatids and sandpipers. The first group had the greatest abundance due to its affinity towards fresh water bodies. The terrains were the favorite sites of dabbling ducks (Anas) and sandpipers. In contrast, two of the most abundant species (Oxyura jamaicensis, 12.5% of all species, and Fulica americana, 8.8 %) restricted their presence to the oxidation lagoons. LO presented a bird structure of its own and atypical, according to the dryness of the region.

Food, feeding, and refuelling of Red Knots during northward migration at San Antonio Oeste, Rio Negro, Argentina

NARCIS (Netherlands)

Gonzalez, PM; Piersma, T; Verkuil, Y; González, Patricia M.

1996-01-01

We studied the food and feeding ecology of Red Knots Calidris canutus rufa on an area of rocky flat, or restinga, near San Antonio Oeste in the northwest of Golfo San Matias, Provincia de Rio Negro, Argentina in March 1992. These Red Knots are on their way north, from ''wintering'' areas in Tierra

Day and night feeding habitat of Red Knots in Patagonia : Profitability versus safety?

NARCIS (Netherlands)

Sitters, HP; Gonzalez, PM; Piersma, T; Baker, AJ; Price, DJ; Sitters, Humphrey P.; González, Patricia M.; Baker, Allan J.; Price, David J.

2001-01-01

By radio-tracking and recording the movements of flocks. the distribution of feeding Red Knots (Calidris canutus rufa) was studied day and night at a migration stopover site near San Antonio Oeste, Rio Negro, Argentina in March and April 1998. By day, the birds fed in dense flocks of 500-4000 on an

Limited Access to Food and Physiological Trade-Offs in a Long-Distance Migrant Shorebird. I. Energy Metabolism, Behavior, and Body-Mass Regulation

NARCIS (Netherlands)

Vezina, Francois; Petit, Magali; Buehler, Deborah M.; Dekinga, Anne; Piersma, Theunis

2009-01-01

Previous experiments showed reduction of basal metabolic rate (BMR) in birds facing energetic challenges. We alternately exposed two groups of red knots (Calidris canutus) to either 6 h or 22 h of food availability for periods of 22 d. Six h of access to food led to a 6%-10% loss of body mass over

Where waders may parallel penguins : Spontaneous increase in locomotor activity triggered by fat depletion in a voluntarily fasting Knot

NARCIS (Netherlands)

Piersma, T.; Poot, M.

1993-01-01

A Knot Calidris canutus, kept with four conspecifics on an enclosed artificial outdoor tidal flat in The Netherlands, refused to feed on the available bivalve prey for a period of 18 days and thereby decreased in mass from 209 g to 107 g, at which point the bird resumed feeding on the then freely

Primeros registros de las garrapatas Amblyomma calcaratum y A. pacae (Acari: Ixodidae) parasitando mamíferos de México

OpenAIRE

Guzmán-Cornejo, Carmen; Pérez, Tila M.; Nava, Santiago; Guglielmone, Alberto A.

2006-01-01

Based on study of ticks deposited in the Colección Nacional de Ácaros, Instituto de Biología, Universidad Nacional Autónoma de México, we report the first records in Mexico for two species of Amblyomma: Amblyomma calcaratum ex Tamandua mexicana, and Amblyomma pacae ex Tapirus bairdii. These new records increase the number of species recorded for the genus Amblyomma in Mexico to 26.Basado en la revisión de garrapatas depositadas en la Colección Nacional de Ácaros, Instituto de Biología, Univer...

Cultural Resources Investigations of the Upper Minnesota River (639) Project, Deuel and Grant Counties, South Dakota, and Lac Qui Parle and Yellow Medicine Counties, Minnesota,

Science.gov (United States)

1984-09-01

Riparia riparia Bank Swallow Megaceryle alcyon Belted Kingfisher Bartramia longicauda Upland Sandpiper -32- Name Common Name * Charadrius vociferus...Smooth sumac Toxicodendron radicans Poison ivy Acer negundo Box elder Parthenocissus vitacea Woodbine Vitis riparia Riverbank grape Tilia americana...within the Prairie-Lakes region are generally located in close proximity to a variety of environmental zones (e.g., upland prairie, slope forest

Great Knot Calidris tenuirostris at Lutembe Bay, Uganda

African Journals Online (AJOL)

Unfortunately it became nervous and flew to another island and we were unable to pursue it before darkness fell. I was, however, able to take some record shots. I circulated the best of four poor photographs to a few birding colleagues for their opinion, and the general consensus favoured Red Knot rather than Great Knot.

COMPARATIVE CHARACTERISTICS OF MORPHOMETRIC PARAMETERS OF MONKEY GOBY (NEOGOBIUS FLUVIATILIS PALLAS OF FRESH AND SALINE WATER RESERVOIRS IN UKRAINE

Directory of Open Access Journals (Sweden)

Onoprienko V.

2014-04-01

Full Text Available The representatives of Pisces family, namely Gobidae are an important component of aquatic ecosystems. With a wide range of adaptation, this group has mastered the different types of fish ponds from completely fresh to the ocean. However, some species are found both in one and in other waters, displaying different (and sometimes conflicting between a life strategy. Last relating to the four main components of the life of fish: water-salt metabolism, nutrition, respiration and reproduction. Mechanisms for implementing these different functions together. First, different concentrations of salts require different types of water- salt metabolism. Another equally important factor is the food base, which is also quite different, both in range and the nature of food. In the sea and reservoirs, over rivers, dissolved oxygen in the water is stratified, and very often in the summer and winter time is in short supply. For bulls, as the bottom of vertebrates, this fact is choking on a large scale. Moreover, in these bodies of water, there are a number of abiotic and biotic factors, which have different requirements in the process of reproduction. The totality of the above conditions vital for fish of Gobidae, makes the need for populations in the gene pool of potential adaptations to survive in those or other settings. Literature data of recent years, the enlargement of habitat bulls, indicating the presence of adaptations. In reservoirs in Ukraine in modern conditions the optimal conditions for Sandpiper observed in the Azov Sea. This contributes greatly to the optimal forage which has emerged over the last decade due to the desalination of sea and favorable conditions for reproduction. In the transition from marine to freshwater Sandpiper flagged fundamentally different and very diverse in every way possible. The difference in environmental conditions differently reflected in the life Bychkov fish, affecting their growth, development and other

COMPARATIVE CHARACTERISTICS OF MORPHOMETRIC PARAMETERS OF MONKEY GOBY (NEOGOBIUS FLUVIATILIS PALLAS OF FRESH AND SALINE WATER RESERVOIRS IN UKRAINE

Directory of Open Access Journals (Sweden)

V. P. Onoprienko

2014-04-01

Full Text Available The representatives of Pisces family, namely Gobidae are an important component of aquatic ecosystems. With a wide range of adaptation, this group has mastered the different types of fish ponds from completely fresh to the ocean. However, some species are found both in one and in other waters, displaying different (and sometimes conflicting between a life strategy. Last relating to the four main components of the life of fish: water-salt metabolism, nutrition, respiration and reproduction. Mechanisms for implementing these different functions together. First, different concentrations of salts require different types of water- salt metabolism. Another equally important factor is the food base, which is also quite different, both in range and the nature of food. In the sea and reservoirs, over rivers, dissolved oxygen in the water is stratified, and very often in the summer and winter time is in short supply. For bulls, as the bottom of vertebrates, this fact is choking on a large scale. Moreover, in these bodies of water, there are a number of abiotic and biotic factors, which have different requirements in the process of reproduction. The totality of the above conditions vital for fish of Gobidae, makes the need for populations in the gene pool of potential adaptations to survive in those or other settings. Literature data of recent years, the enlargement of habitat bulls, indicating the presence of adaptations. In reservoirs in Ukraine in modern conditions the optimal conditions for Sandpiper observed in the Azov Sea. This contributes greatly to the optimal forage which has emerged over the last decade due to the desalination of sea and favorable conditions for reproduction. In the transition from marine to freshwater Sandpiper flagged fundamentally different and very diverse in every way possible. The difference in environmental conditions differently reflected in the life Bychkov fish, affecting their growth, development and other

Diversidad,historia natural y conservación de los mamíferos de San Vito de Coto Brus, Costa Rica

Directory of Open Access Journals (Sweden)

Jesús Pacheco

2006-03-01

Full Text Available Aunque Costa Rica ha sido biológicamente bien estudiada, pocas áreas tiene inventarios de mamíferos completos y actualizados,lo que es para llevar a cabo estudios ecológicos y de conservación. La región de San Vito es considerada entre las mas importantes para la investigación científica en el país, debido a la presencia del Jardín Botánico Wilson y la Estación Biológica Las Cruces. Sin embargo, el conocimiento de la mastofauna es incompleto. Por lo tanto se evaluó intensamente los mamíferos de San Vito, y se compiló una lista de especies, con una evaluación de su composición, abundancia relativa, distribución en los habitats, y su estado de conservación. Se registraron 105 especies, que representaron a 85 géneros, 29 familias y 10 órdenes. Los mamíferos no voladores representaron 62 especies, 59 géneros, 23 familias y 9 órdenes. Los murciélagos pertenecieron a 6 familias, 26 géneros y 43 especies. La extensa deforestación y cacería son factores que han causado la extinción local de 7especies, pero la región todavía mantiene un número relativamente alto de su diversidad original, incluyendo a especie raras. Pocas especies fueron comunes o abundantes. La riqueza de especies fue alta en el bosque y los fragmentos de bosque, y más baja en las plantaciones de café, pastizales inducidos y vegetación secundaria. Alrededor del 21% (13 de las espcies estan incluidad en el libro rojo de la UICN. Tres especies (Saimiri oerstedii, Tapirus bairdii y Sylvilagus dicei son consideradas en peligro y dos (Myrmecophaga trydactila y Caluromys derbianus como amenazadas:de estas, dos especies (T. bairdii and M. trydactila se encuentran localmente extintas. Las otras especies son consideradas de bajo riesgo (i. e. Chironectes minimus o con poca información (i. e. Lontra longicaudis . Adicionalmente, 24 especies (39% están incluidas en CITES.Diversity, natural history and conservation of mammals from San Vito de Coto Brus, Costa

Salida de campo a Suances (Cantabria) el 27 y 28 de agosto de 1950

OpenAIRE

Valverde Gómez, José Antonio, 1926-2003

2008-01-01

Salida de campo a Suances, Cantabria, el 27 y 28 de agosto de 1950, de la que se anotaron observaciones sobre las siguientes aves: Actitis hypoleucos (Andarríos chico, llamado Actynioides hypoleucus por el autor), Arenaria interpres (Vuelvepiedras común), Calidris sp. (Correlimos), Carduelis cannabina (Pardillo común, llamada Colorín y Acanthis cannabina por el autor), Carduelis carduelis (Jilguero), Charadrius hiaticula (Chorlitejo grande), Corvus corax (Cuervo), Falco tinnunculus (Cernícalo...

Interspecific variation in the tetradactyl manus of modern tapirs (Perissodactyla: Tapirus) exposed using geometric morphometrics.

Science.gov (United States)

MacLaren, Jamie A; Nauwelaerts, Sandra

2017-11-01

The distal forelimb (autopodium) of quadrupedal mammals is a key morphological unit involved in locomotion, body support, and interaction with the substrate. The manus of the tapir (Perissodactyla: Tapirus) is unique within modern perissodactyls, as it retains the plesiomorphic tetradactyl (four-toed) condition also exhibited by basal equids and rhinoceroses. Tapirs are known to exhibit anatomical mesaxonic symmetry in the manus, although interspecific differences and biomechanical mesaxony have yet to be rigorously tested. Here, we investigate variation in the manus morphology of four modern tapir species (Tapirus indicus, Tapirus bairdii, Tapirus pinchaque, and Tapirus terrestris) using a geometric morphometric approach. Autopodial bones were laser scanned to capture surface shape and morphology was quantified using 3D-landmark analysis. Landmarks were aligned using Generalised Procrustes Analysis, with discriminant function and partial least square analyses performed on aligned coordinate data to identify features that significantly separate tapir species. Overall, our results support the previously held hypothesis that T. indicus is morphologically separate from neotropical tapirs; however, previous conclusions regarding function from morphological differences are shown to require reassessment. We find evidence indicating that T. bairdii exhibits reduced reliance on the lateral fifth digit compared to other tapirs. Morphometric assessment of the metacarpophalangeal joint and the morphology of the distal facets of the lunate lend evidence toward high loading on the lateral digits of both the large T. indicus (large body mass) and the small, long limbed T. pinchaque (ground impact). Our results support other recent studies on T. pinchaque, suggesting subtle but important adaptations to a compliant but inclined habitat. In conclusion, we demonstrate further evidence that the modern tapir forelimb is a variable locomotor unit with a range of interspecific features

A supertree approach to shorebird phylogeny

Directory of Open Access Journals (Sweden)

Thomas Gavin H

2004-08-01

Full Text Available Abstract Background Order Charadriiformes (shorebirds is an ideal model group in which to study a wide range of behavioural, ecological and macroevolutionary processes across species. However, comparative studies depend on phylogeny to control for the effects of shared evolutionary history. Although numerous hypotheses have been presented for subsets of the Charadriiformes none to date include all recognised species. Here we use the matrix representation with parsimony method to produce the first fully inclusive supertree of Charadriiformes. We also provide preliminary estimates of ages for all nodes in the tree. Results Three main lineages are revealed: i the plovers and allies; ii the gulls and allies; and iii the sandpipers and allies. The relative position of these clades is unresolved in the strict consensus tree but a 50% majority-rule consensus tree indicates that the sandpiper clade is sister group to the gulls and allies whilst the plover group is placed at the base of the tree. The overall topology is highly consistent with recent molecular hypotheses of shorebird phylogeny. Conclusion The supertree hypothesis presented herein is (to our knowledge the only complete phylogenetic hypothesis of all extant shorebirds. Despite concerns over the robustness of supertrees (see Discussion, we believe that it provides a valuable framework for testing numerous evolutionary hypotheses relating to the diversity of behaviour, ecology and life-history of the Charadriiformes.

Fuel use and metabolic response to endurance exercise: a wind tunnel study of a long-distance migrant shorebird

OpenAIRE

Jenni-Eiermann, Susanne; Jenni, Lukas; Kvist, Anders; Lindström, Åke; Piersma, Theunis; Visser, G. Henk

2002-01-01

This study examines fuel use and metabolism in a group of long-distance migrating birds, red knots Calidris canutus (Scolopacidae), flying under controlled conditions in a wind tunnel for up to 10 h. Data are compared with values for resting birds fasting for the same time. Plasma levels of free fatty acids, glycerol and uric acid were elevated during flight, irrespective of flight duration (1–10 h). Triglyceride levels, the estimated concentration of very-low-density lipoproteins (VLDLs) and...

Bird poisoning from misuse of the carbamate Furadan in a Texas rice field

Science.gov (United States)

Flickinger, Edward L.; Mitchell, C.A.; White, D.H.; Kolbe, E.J.

1986-01-01

More than 100 birds consisting largely of dickcissels and savannah sparrows, as well as 9 other species of songbirds and sandpipers, died from feeding on planted rice seed treated illegally with Furadan 4F. Brain ChE activity was depressed between 32-85% in 44% of the birds. Carbofuran residues in GI tract contents of birds averaged 3.4 ppm (0.54-10 ppm). Two samples of planted rice seed contained 91 ppm and 22 ppm carbofuran. Known mortality of birds continued for about 2 weeks.

When the Seasons Don't Fit: Speedy Molt as a Routine Carry-Over Cost of Reproduction

OpenAIRE

Dietz, M.W.; Rogers, K.G.; Piersma, T.

2013-01-01

The failure of animals to fit all life-cycle stages into an annual cycle could reduce the chances of successful breeding. In some cases, non-optimal strategies will be adopted in order to maintain the life-cycle within the scope of one year. We studied trade-offs made by a High Arctic migrant shorebird, the red knot Calidris canutus islandica, between reproduction and wing feather molt carried out in the non-breeding period in the Dutch Wadden Sea. We compared primary molt duration between bi...

[Parasites of the Central American tapir Tapirus bairdii (Perissodactyla: Tapiridae) in Chiapas, Mexico].

Science.gov (United States)

Cruz Aldán, Epigmenio; Lira Torres, Iván; Güiris Andrade, Dario Marcelino; Osorio Sarabia, David; Quintero M, Ma Teresa

2006-06-01

We analyzed 19 samples of Baird's tapir feces from La Sepultura Biosphere Reserve, collected between March and July 1999. We also took samples directly from a male tapir captured at the Montes Azules Biosphere Reserve. Both reserves are in Chiapas, Mexico. We used five techniques: flotation, MacMaster, micrometric, Ritchie's sedimentation and Ferreira's quantitative. In addition, we collected ectoparasites from animals captured in both reserves and from a captive couple from Tuxtla Gutierrez, Chiapas. These nematodes and protozoans were found: Agriostomun sp., Lacandoria sp., Neomurshidia sp., Trichostrongylus sp., Strongylus sp., Brachylumus sp, and an unidentified species of ancilostomaide. We also found Eimeria sp. and Balantidium coli, as well as the mites Dermacentor halli, Dermacentor latus, Amblyomma cajannense, Amblyomma coelebs, Amblyomma ovale, Anocentor nitens and Ixodes bicornis.

Iron storage disease in tapirs.

Science.gov (United States)

Bonar, Christopher J; Trupkiewicz, John G; Toddes, Barbara; Lewandowski, Albert H

2006-03-01

Recent studies of serum iron and iron binding capacity have indicated that tapirs could be at risk of developing hemochromatosis. However, in recent surveys of pathologic findings in tapirs, hemochromatosis was not reported as a cause of death. This study reviews necropsy reports from three species of tapir (Baird's tapir [Tapirus bairdii], Malayan tapir [Tapirus indicus], and Brazilian tapir [Tapirus terrestris]) at the Philadelphia Zoological Garden between 1902 and 1994. Twelve cases of hemosiderosis, including fatal hemochromatosis in two Baird's tapirs, were found among 19 cases examined histologically. Hemochromatosis has previously been reported in the horse, rhinoceros, and in one Brazilian tapir. Dietary factors were investigated but could not be confirmed to have contributed to the incidence of hemosiderosis and hemochromatosis in the three species of tapir in the Philadelphia Zoological Garden collection.

Birds and wind turbines: can they co-exist?

International Nuclear Information System (INIS)

Still, David.

1996-01-01

The wind farm is situated along an exposed pier at Blyth Harbour and has now been designated as part of a SSI and part of a proposed RAMSAR site. The bird activity within the harbour is high and is also the wintering home of the Purple Sandpiper. An offshore wind farm is proposed for the area, one kilometre from the pier. Two turbines will be erected with the support of the European Commission THERMIE Programme. The bird study at Blyth has been funded by Border Wind, Blyth Harbour Wind Farm Company and the DTI as part of an ETSU funded study. (UK)

Mamíferos terrestres de la Reserva de la Biosfera de Sian Ka’an, Quintana Roo, México

Directory of Open Access Journals (Sweden)

Carmen Pozo de la Tijera

1999-06-01

Full Text Available Con base en el muestreo de siete localidades y una extensa revisión bibliográfica, se obtuvo la lista de especies de mamíferos terrestres de la Reserva de la Biosfera de Sian Ka’an estado de Quintana Roo, México. Durante 57 días de campo, se utilizaron trampas Sherman, Tomahawk, redes de niebla y escopetas, se registraron rastros y observaciones directas. Se registraron 70 especies, ocho órdenes, 22 familias y 57 géneros. Se encontraron seis especies como nuevos registros: Marmosa mexicana, Micronycteris microtis, Micronycteris schmidtorum, Eptesicus furinalis, Rhogeessa parvula y Ototylomys phyllotis. Doce especies son catalogadas bajo algún riesgo ecológico según la Norma Oficial Mexicana; trece especies son endémicas a Mesoamérica y una endémica de México. Se presentan cuadros de abundancia relativa, registro por localidades y por tipo de vegetación de cada especie.Based on sampling at seven localities and an extensive bibliographic research, we present a species list of terrestrial mammals of the Sian Ka’an Biosphere Reserve, Quintana Roo, Mexico. During 57 days of fieldwork we used Sherman and Tomahawk traps, mist nets, rifles, collected data of trails and made direct observations. We recorded 70 species, eight orders, 22 families, and 57 genera. Six new records are added: Marmosa mexicana, Micronycteris microtis, Micronycteris schmidtorum, Eptesicus furinalis, Rhogeessa parvula, and Ototylomys phyllotis. Twelve species are listed as threatened following the Official Mexican Norm: Tamandua mexicana, Micronycteris brachyotis, Lonchorhina aurita, Alouatta pigra, Ateles geoffroyi, Herpailurus yagouaroundi, Leopardus pardalis, Leopardus wiedii, Panthera onca, Eira barbara, Potos flavus and Tapirus bairdii. Thirteen species are endemic to Mesoamerica: M. mexicana, T. mexicana, Mormoops megalophylla, Tonatia evotis, Bauerus dubiaquercus, A. pigra, A. geoffroyi, T. bairdii, Sciurus deppei, Sciurus yucatanensis, Heteromys gaumeri

REDSHANK I and GREENSHANK I (comprehensive point reactivity programmes for liquid moderated UO2 lattices)

International Nuclear Information System (INIS)

Alpiar, R.A.

1963-08-01

A recently issued programme (SANDPIPER I) enables few group diffusion parameters and reactivities to be derived for liquid moderated UO 2 lattices. The present programmes investigate the life history of such lattices. Burn up equations recalculate the fuel isotopic composition, in a series of steps. At each step, new few group constants and reactivity are recalculated for the new fuel composition. In addition, at each step, the control required to keep the reactivity of the reactor within a given deadband is recalculated. This control is effected by control rod withdrawal in Redshank, and by heavy water spectrum shift in Greenshank. The programme continues until the reactivity of the uncontrolled reactor falls below the deadband. (author)

REDSHANK I and GREENSHANK I (comprehensive point reactivity programmes for liquid moderated UO{sub 2} lattices)

Energy Technology Data Exchange (ETDEWEB)

Alpiar, R A [Technical Assessments and Services Division, Atomic Energy Establishment, Winfrith, Dorchester, Dorset (United Kingdom)

1963-08-15

A recently issued programme (SANDPIPER I) enables few group diffusion parameters and reactivities to be derived for liquid moderated UO{sub 2} lattices. The present programmes investigate the life history of such lattices. Burn up equations recalculate the fuel isotopic composition, in a series of steps. At each step, new few group constants and reactivity are recalculated for the new fuel composition. In addition, at each step, the control required to keep the reactivity of the reactor within a given deadband is recalculated. This control is effected by control rod withdrawal in Redshank, and by heavy water spectrum shift in Greenshank. The programme continues until the reactivity of the uncontrolled reactor falls below the deadband. (author)

Western sandpipers have altered migration tactics as peregrine falcon populations have recovered

NARCIS (Netherlands)

Ydenberg, R.C.; Butler, R.W.; Lank, D.B.; Smith, B.D.; Ireland, J.

2004-01-01

The presence of top predators can affect prey behaviour, morphology and life history, and thereby can produce indirect population consequences greater and further reaching than direct depredation would have alone. Raptor species in the Americas are recovering since restrictions on the use of

Evolution of monogamy, paternal investment, and female life history in Peromyscus.

Science.gov (United States)

Jašarević, Eldin; Bailey, Drew H; Crossland, Janet P; Dawson, Wallace D; Szalai, Gabor; Ellersieck, Mark R; Rosenfeld, Cheryl S; Geary, David C

2013-02-01

The timing of reproductive development and associated trade-offs in quantity versus quality of offspring produced across the life span are well documented in a wide range of species. The relation of these aspects of maternal life history to monogamy and paternal investment in offspring is not well studied in mammals, due in part to the rarity of the latter. By using five large, captive-bred populations of Peromyscus species that range from promiscuous mating with little paternal investment (P. maniculatus bairdii) to social and genetic monogamy with substantial paternal investment (P. californicus insignis), we modeled the interaction between monogamy and female life history. Monogamy and high paternal investment were associated with smaller litter size, delayed maternal reproduction that extended over a longer reproductive life span, and larger, higher quality offspring. The results suggest monogamy and paternal investment can alter the evolution of female life-history trajectories in mammals. PsycINFO Database Record (c) 2013 APA, all rights reserved

Viability of small seeds found in feces of the Central American tapir on Barro Colorado Island, Panama.

Science.gov (United States)

Capece, Paula I; Aliaga-Rossel, Enzo; Jansen, Patrick A

2013-03-01

Tapirs are known as effective dispersers of large-seeded tree species, but their role in dispersing small-seeded plant species has yet to be established. Tapir feces have been reported to contain large numbers of small seeds, but whether these are viable has rarely been evaluated. We determined the abundance and viability of small seeds in feces of Central American tapir (Tapirus bairdii) on Barro Colorado Island, Panama. A total of 72 fecal samples were collected opportunistically from 4 tapir latrine sites. Seeds were manually extracted from feces and classified by size. Seed viability was estimated by opening each seed and examining for the presence of at least 1 intact firm white endosperm. In total, we obtained 8166 seeds of at least 16 plant species. Small-seeded species dominated, with 96% of all seeds found measuring tapirs potentially serve as effective dispersers of a wide range of small-seeded plant species. © 2012 Wiley Publishing Asia Pty Ltd, ISZS and IOZ/CAS.

The birds of Blyth Harbour

International Nuclear Information System (INIS)

Still, D.; Carver, H.; Little, B.; Lawrence, S.G.

1995-01-01

Blyth Harbour Wind Farm, constructed upon an exposed pier, is not a Site of Special Scientific Interest and is designated to become a RAMSAR location because of the presence of a significant population of the Purple Sandpiper. A study of the effect of the wind farm on the birds was started before the wind farm was constructed and is ongoing. Initial evidence of how the wind turbines have affected the 110 varieties of birds recorded within the harbour will be presented and compared to previous research carried out in Europe and the USA. Methodology has included intensive beach surveys, visits to wind farms in the UK and USA and consultations with wildlife advisory bodies. The study will continue until 1996. (Author)

Assemblages of deep-sea fishes on the middle slope off Northwest Africa (26°-33° N, eastern Atlantic)

Science.gov (United States)

Pajuelo, J. G.; Seoane, J.; Biscoito, M.; Freitas, M.; González, J. A.

2016-12-01

The structure and composition of deep-sea fish assemblages living on the middle slope off NW Africa (26-33° N) were investigated. Data were collected by six commercial trawlers during experimental fishing (1027 hauls) at depths between 800 and 1515 m. A total of 1,115,727 fish specimens, belonging to 37 families and 96 species (24 Elasmobranchii, 5 Holocephali, and 67 Actinopteri) were collected with bottom trawls. The deep-sea demersal fish fauna off NW Africa is dominated by fishes of the family Macrouridae, followed by the Moridae and Alepocephalidae families. The main abundant species were Trachyrincus scabrus, Bathygadus favosus, Mora moro, Alepocephalus productus, Nezumia aequalis and Bathygadus melanobranchus. PERMANOVA analysis showed differences in demersal fish assemblages among bottom types, depth strata and between areas (north and south of parallel 30° N), with the area being the most influential factor followed by the type of substrate. PERMANOVAs computed separately for each area showed significant differences among the bottom types and depths in both areas. SIMPER analysis revealed that B. melanobranchus and B. favosus, which occurred at higher abundances in the area ≥30° N, were the species that were best discriminated between areas; whilst T. scabrus and M. moro occurred at higher abundances in the area <30° N. N. aequalis, B. favosus, B. melanobranchus, Deania hystricosa, Aphanopus intermedius, Coelorinchus labiatus and Halosaurus johnsonianus were restricted or more abundant in the area ≥30° N, and functioned as the discriminating species that most contributed to the average dissimilarity between areas. T. scabrus, M. moro, Alepocephalus productus and Alepocephalus bairdii were more abundant in the area <30° N. The standardized mean abundance (in number of individuals/km2) showed a decreasing pattern: i) with depth in both areas, north and south of parallel 30° N, and ii) with depth on each type of substrate, except on cold coral

Influence of age and sex on winter site fidelity of sanderlings Calidris alba

Directory of Open Access Journals (Sweden)

Pedro M. Lourenço

2016-09-01

Full Text Available Many migratory bird species show high levels of site fidelity to their wintering sites, which confers advantages due to prior knowledge, but may also limit the ability of the individual to move away from degrading sites or to detect alternative foraging opportunities. Winter site fidelity often varies among age groups, but sexual differences have seldom been recorded in birds. We studied a population of individually colour-marked sanderlings wintering in and around the Tejo estuary, a large estuarine wetland on the western coast of Portugal. For 160 individuals, sighted a total of 1,249 times between November 2009 and March 2013, we calculated the probability that they moved among five distinct wintering sites and how this probability is affected by distance between them. To compare site fidelity among age classes and sexes, as well as within the same winter and over multiple winters, we used a Site Fidelity Index (SFI. Birds were sexed using a discriminant function based on biometrics of a large set of molecularly sexed sanderlings (n = 990. The vast majority of birds were observed at one site only, and the probability of the few detected movements between sites was negatively correlated with the distance among each pair of sites. Hardly any movements were recorded over more than 15 km, suggesting small home ranges. SFI values indicated that juveniles were less site-faithful than adults which may reflect the accumulated knowledge and/or dominance of older animals. Among adults, females were significantly less site faithful than males. A sexual difference in winter site fidelity is unusual in shorebirds. SFI values show site-faithfulness is lower when multiple winters were considered, and most birds seem to chose a wintering site early in the season and use that site throughout the winter. Sanderlings show a very limited tendency to explore alternative wintering options, which might have implications for their survival when facing habitat change or loss (e.g., like severe beach erosion as can be the case at one of the study sites.

Ecology and local knowledge of the Baird's tapir (Tapirella bairdii) in the Sierra Madre de Oaxaca, Mexico.

Science.gov (United States)

Lavariega Nolasco, Mario César; Briones-Salas, Miguel; Mazas-Teodocio, Amado; Durán-Medina, Elvira

2016-09-01

As well as being of global cultural importance (from local tribal folklore to being an iconic species for conservation), the tapir plays an important role in its ecosystem as a herbivore and seed disperser. However, the ecology and ethnozoology of the endangered Baird's tapir in the north of Oaxaca, Mexico is poorly understood. We used camera traps to estimate its relative abundance and density and to describe the activity patterns of the northernmost population of Baird's tapir in the Sierra Madre de Oaxaca. Local knowledge concerning the tapir was also documented, along with the conservation strategies undertaken by the 2 indigenous communities that own the land where the study site is located. Only adult tapirs were photographed, and these were active 14 h per day, but were mainly nocturnal and crepuscular. The estimated relative abundance (12.99 ± 2.24 events/1000 camera days) and density values (0.07-0.24 individuals/km(2) ) were both similar to those found in another site in Mexico located within a protected area. Semi-structured interviews revealed that people have a basic understanding of the eating habits, activity and main predators of the tapir. There were reports of hunting, although not among those respondents who regularly consume bush meat. Thus, the relative abundance and density estimates of tapir at the study site could be related to the favorable condition of the forest and the absence of hunting and consumption of tapir meat. Fortunately, the local people are conducting initiatives promoting the conservation of this ungulate and its habitat that combine to constitute a regional trend of habitat and wildlife protection. © 2016 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

Burlington Bottoms Wildlife Mitigation Project. Final Environmental Assessment/Management Plan and Finding of No Significant Impact.

Energy Technology Data Exchange (ETDEWEB)

1994-12-01

Bonneville Power Administration (BPA) proposes to fund wildlife management and enhancement activities for the Burlington bottoms wetlands mitigation site. Acquired by BPA in 1991, wildlife habitat at Burlington bottoms would contribute toward the goal of mitigation for wildlife losses and inundation of wildlife habitat due to the construction of Federal dams in the lower Columbia and Willamette River Basins. Target wildlife species identified for mitigation purposes are yellow warbler, great blue heron, black-capped chickadee, red-tailed hawk, valley quail, spotted sandpiper, wood duck, and beaver. The Draft Management Plan/Environmental Assessment (EA) describes alternatives for managing the Burlington Bottoms area, and evaluates the potential environmental impacts of the alternatives. Included in the Draft Management Plan/EA is an implementation schedule, and a monitoring and evaluation program, both of which are subject to further review pending determination of final ownership of the Burlington Bottoms property.

Burlington Bottoms Wildlife Mitigation Project. Final environmental assessment/management plan and finding of no significant impact

International Nuclear Information System (INIS)

1994-12-01

Bonneville Power Administration (BPA) proposes to fund wildlife management and enhancement activities for the Burlington bottoms wetlands mitigation site. Acquired by BPA in 1991, wildlife habitat at Burlington bottoms would contribute toward the goal of mitigation for wildlife losses and inundation of wildlife habitat due to the construction of Federal dams in the lower Columbia and Willamette River Basins. Target wildlife species identified for mitigation purposes are yellow warbler, great blue heron, black-capped chickadee, red-tailed hawk, valley quail, spotted sandpiper, wood duck, and beaver. The Draft Management Plan/Environmental Assessment (EA) describes alternatives for managing the Burlington Bottoms area, and evaluates the potential environmental impacts of the alternatives. Included in the Draft Management Plan/EA is an implementation schedule, and a monitoring and evaluation program, both of which are subject to further review pending determination of final ownership of the Burlington Bottoms property

Multidirectional cross-species painting illuminates the history of karyotypic evolution in Perissodactyla.

Science.gov (United States)

Trifonov, Vladimir A; Stanyon, Roscoe; Nesterenko, Anastasia I; Fu, Beiyuan; Perelman, Polina L; O'Brien, Patricia C M; Stone, Gary; Rubtsova, Nadezhda V; Houck, Marlys L; Robinson, Terence J; Ferguson-Smith, Malcolm A; Dobigny, Gauthier; Graphodatsky, Alexander S; Yang, Fengtang

2008-01-01

The order Perissodactyla, the group of odd-toed ungulates, includes three extant families: Equidae, Tapiridae, and Rhinocerotidae. The extremely rapid karyotypic diversification in perissodactyls has so far prevented the establishment of genome-wide homology maps between these three families by traditional cytogenetic approaches. Here we report the first genome-wide comparative chromosome maps of African rhinoceroses, four tapir species, four equine species, and humans. These maps were established by multidirectional chromosome painting, with paint probes derived from flow-sorted chromosomes of Equus grevyi, Tapirus indicus, and Ceratotherium simum as well as painting probes from horse and human. The Malayan tapir (Tapirus indicus), Baird's tapir (T. bairdii), mountain tapir (T. pinchaque), lowland tapir (T. terrestris), and onager (E. hemionus onager), were studied by cross-species chromosome painting for the first time. Our results, when integrated with previously published comparative chromosome maps of the other perissodactyl species, have enabled the reconstruction of perissodactyl, ceratomorph, and equid ancestral karyotypes, and the identification of the defining evolutionary chromosomal rearrangements along each lineage. Our results allow a more reliable estimate of the mode and tempo of evolutionary chromosomal rearrangements, revealing a striking switch between the slowly evolving ceratomorphs and extremely rapidly evolving equids.

Mortality-minimizing sandpipers vary stopover behavior dependent on age and geographic proximity to migrating predators

NARCIS (Netherlands)

Hope, D.D.; Lank, D.B.; Ydenberg, R.C.

2014-01-01

Ecological theory for long-distance avian migration considers time-, energy-, and mortality-minimizing tactics, but predictions about the latter have proven elusive. Migrants must make behavioral decisions that can favor either migratory speed or safety from predators, but often not both. We compare

Arctic-nesting birds find physiological relief in the face of trophic constraints.

Science.gov (United States)

McKinnon, Laura; Nol, Erica; Juillet, Cédric

2013-01-01

A climate-induced phenological mismatch between the timing of reproduction and the timing of food resource peaks is one of the key hypothesized effects of climate change on wildlife. Though supported as a mechanism of population decline in birds, few studies have investigated whether the same temperature increases that drive this mismatch have the potential to decrease energetic costs of growth and compensate for the potential negative effects of reduced food availability. We generated independent indices of climate and resource availability and quantified their effects on growth of Dunlin (Calidris alpina) chicks, in the sub-arctic tundra of Churchill, Manitoba during the summers of 2010-2011 and found that when resource availability was below average, above average growth could be maintained in the presence of increasing temperatures. These results provide evidence that chicks may find physiological relief from the trophic constraints hypothesized by climate change studies.

Trends of some wintering waterbirds in Lazio (1993-2006

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Massimo Brunelli

2012-09-01

Full Text Available Since the 90s, censuses of wintering waterfowl have been carried out in the main wetlands of Lazio. We analysed the trends of 31 species in the 1993-2006 period (base year 1993 by means of TRIM (Trends and Indices Monitoring data software (Model 3. Among the species regularly recorded in the region, Ardea alba, Ardea cinerea, Bubulcus ibis and Anser anser showed a strong increase; Podiceps cristatus, Nycticorax nycticorax, Egretta garzetta, Phoenicopterus ruber, Anas penelope, Anas strepera, Anas crecca, Anas platyrhynchos, Anas clypeata, Netta rufina, Aythya ferina, Aythya nyroca, Circus aeruginosus, Fulica atra, Pluvialis apricaria and Vanellus vanellus showed a moderate increase; Gavia arctica, Tachybaptus ruficollis, Podiceps nigricollis, Phalacrocorax carbo, Aythya fuligula and Numenius arquata resulted “stable”; Botaurus stellaris, Tadorna tadorna, Anas acuta, Pluvialis squatarola and Calidris alpina showed an uncertain trend. The trends for most species are similar to those recorded at a national level.

Foraging in a tidally structured environment by red knots (Calidris canutus) : Ideal, but not free

NARCIS (Netherlands)

van Gils, JA; Spaans, B; Dekinga, A; Piersma, T; Speirs, D.C.

Besides the "normal" challenge of obtaining adequate intake rates in a patchy and dangerous world, shorebirds foraging in intertidal habitats face additional environmental hurdles. The tide forces them to commute between a roosting site and feeding grounds, twice a day. Moreover, because intertidal

Foraging in a tidally structured environment by red knots (Calidris canutus): Ideal, but not free

NARCIS (Netherlands)

Van Gils, J.A.; Spaans, B.; Dekinga, A.; Piersma, T.

2006-01-01

Besides the “normal” challenge of obtaining adequate intake rates in a patchy and dangerous world, shorebirds foraging in intertidal habitats face additional environmental hurdles. The tide forces them to commute between a roosting site and feeding grounds, twice a day. Moreover, because intertidal

The effects of differential prenatal and postnatal social enviroments on sexual maturation of young prairie deermice (Peromyscus maniculatus bairdii).

Science.gov (United States)

Thomas, D; Terman, C R

1975-05-01

We compared the influence of different social enviroments on sexual maturation of young prairie deermice. Between 12 and 48 hr after parturition, one-half of a litter from a population was exchanged with one-half of a litter from a bisexual pair. In each situation the remaining half-litter served as controls for the exchange procedure. The testes and vesicular weights of population-reared males were significantly larger than those of males reared by bisexual pairs, irrespective of prenatal enviroment. Generally, population-reared females also had larger reproductive organs than those reared by bisexual pairs, although these differences were not statistically significant. There were no significant differences in the adrenal weights of males or females, but females reared by bisexual pairs had larger absolute and relative adrenals than females reared in populations.

Trapped in the extinction vortex? Strong genetic effects in a declining vertebrate population

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Larsson Mikael

2010-02-01

Full Text Available Abstract Background Inbreeding and loss of genetic diversity are expected to increase the extinction risk of small populations, but detailed tests in natural populations are scarce. We combine long-term population and fitness data with those from two types of molecular markers to examine the role of genetic effects in a declining metapopulation of southern dunlins Calidris alpina schinzii, an endangered shorebird. Results The decline is associated with increased pairings between related individuals, including close inbreeding (as revealed by both field observations of parentage and molecular markers. Furthermore, reduced genetic diversity seems to affect individual fitness at several life stages. Higher genetic similarity between mates correlates negatively with the pair's hatching success. Moreover, offspring produced by related parents are more homozygous and suffer from increased mortality during embryonic development and possibly also after hatching. Conclusions Our results demonstrate strong genetic effects in a rapidly declining population, emphasizing the importance of genetic factors for the persistence of small populations.

Baird's tapir density in high elevation forests of the Talamanca region of Costa Rica.

Science.gov (United States)

González-Maya, José F; Schipper, Jan; Polidoro, Beth; Hoepker, Annelie; Zárrate-Charry, Diego; Belant, Jerrold L

2012-12-01

Baird's tapir (Tapirus bairdii) is currently endangered throughout its neotropical range with an expected population decline >50% in the next 30 years. We present the first density estimation of Baird's tapir for the Talamanca mountains of Costa Rica, and one of the first for the country. Ten stations with paired cameras were established in Valle del Silencio within Parque Internacional La Amistad (PILA). Seventy-seven tapir pictures of 15 individuals comprising 25 capture-recapture events were analyzed using mark-recapture techniques. The 100% minimum convex polygon of the sampled area was 5.7 km(2) and the effective sampled area using half mean maximum distances moved by tapirs was 7.16 km(2) . We estimated a tapir density of 2.93 individuals/km(2) which represents the highest density reported for this species. Intermountain valleys can represent unique and important habitats for large mammal species. However, the extent of isolation of this population, potentially constrained by steep slopes of the cordillera, remains unknown. Further genetic and movement studies are required to understand meta-population dynamics and connectivity between lowland and highland areas for Baird's tapir conservation in Costa Rica. © 2012 Wiley Publishing Asia Pty Ltd, ISZS and IOZ/CAS.

The occurrence of an abdominal fauna in an articulated tapir (Tapirus polkensis) from the Late Miocene Gray Fossil Site, Northeastern Tennessee.

Science.gov (United States)

McCONNELL, Shannon M; Zavada, Michael S

2013-03-01

The analysis of samples recovered from the abdominal area of an articulated tapir (Tapirus polkensis) from the Late Miocene (4.5-7 million BP) Gray Fossil Site (GFS) revealed a rich palyno-fauna comprised of about 94% egg/oocyst-like structures and 6% pollen and other palynomorphs. In addition, a group of 6 hickory nuts (Carya) was recovered from the same area suggesting that the samples represent the abdominal contents. The analysis of a sample from immediately outside the tapir produced a sample with 98% pollen and less than 0.5% egg/oocyst-like structures. The size, shape, and general morphology of egg/oocyst-like structures were analyzed with light and scanning electron microscopy and were compared to a variety of intestinal parasites found in extant ungulates, and the Perissodactyla in particular. We also compared fossil structures to the numbers and kind of intestinal parasites recovered from fecal samples from the Baird's tapir (T. bairdii) in Costa Rica and from samples collected from the lowland tapir (T. terrestris) from Ecuador to assess their similarity to our fossil sample. Based on these data, we discuss what role parasites may have played in the biology of T. polkensis during the Late Miocene-Early Pliocene. © 2012 Wiley Publishing Asia Pty Ltd, ISZS and IOZ/CAS.

Work plan for the treatability study for PCB dehalogenation by Agent 313 in Waste Area Grouping 11 at Oak Ridge National Laboratory, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

1994-08-01

This work Plan describes the treatability study for Polychlorinated biphenyl (PCB) debalogenation by Agent 313 (a registered trademark of the A.L. Sandpiper Corporation of Columbus, ohio) to be conducted at Waste Area Grouping (WAG) 11 on the Oak Ridge Reservation. The study will be conducted at WAG 11 as a result of the contamination of several small areas of soil by leaking capacitors. The primary purpose of this treatability study is to demonstrate the effectiveness of Agent 313 in remediating PCB-contaminated soil. However, the WAG 11 soils to be treated may also contain radionuclides and metals. In addition to providing the procedures to be followed during the treatability study, the work plan briefly describes the project background and technology, lists applicable or relevant and appropriate requirements for the project, and delineates project goals and objectives. This document also follows the general suggested outline for treatability study work plans shown in the 1992 report Guide for conducting Treatability Studies Under CERCLA: Final, EPA;540/R-92-071a, published by the US Environmental Protection Agency

RECONSTRUCTING DIET COMPOSITION ON THE BASIS OF FECES IN A MOLLUSK-EATING WADER, THE KNOT CALIDRIS-CANUTUS

NARCIS (Netherlands)

DEKINGA, A; PIERSMA, T

Methods are described to assess the molluscan diet of Knots feeding on intertidal flats in western Europe from their faecal output. The size distributions of two common bivalve prey, Macoma balthica and Cerastoderma edule, can be estimated from the heights of shell hinges retrieved from droppings.

Reconstructing diet composition on the basis of faeces in a mollusc-eating wader, the Knot Calidris canutus

NARCIS (Netherlands)

Dekinga, A.; Piersma, T.

1993-01-01

Methods are described to assess the molluscan diet of Knots feeding on intertidal flats in western Europe from their faecal output. The size distributions of two common bivalve prey, Macoma balthica and Cerastoderma edule, can be estimated from the heights of shell hinges retrieved from droppings.

TRADITIONAL RURAL WETLANDS IN HARYANA STATE OF INDIA ARE CURRENTLY CONFRONTING MULTICORNERED THREATS LEADING TO EXTINCTION SOONER THAN LATER

Directory of Open Access Journals (Sweden)

Rohtash chand Gupta

2012-05-01

indicus, Mallard Anas platyrhynchos, Gadwall Anas strepera, Northern Shoveller Anas clypeata, Northern Pintail Anas acuta, Garganey Anas querquedula, Common Teal Anas crecca, Common Pochard Aythya ferina, Tufted Pochard Aythya fuligula, Common Coot Fulica atra, Little Ringed Plover Charadrius dubius, Kentish Plover Charadrius alexandrines, Spotted Redshank Tringa erythropus, Common Redshank Tringa tetanus, Marsh Sandpiper Tringa stagnatilis, Wood Sandpiper Tringa glareola and Pied Avocet Recurivirostra avosetta arrive in the extremely dilapidated rural ponds in Haryana from far off places including Russia, Siberia, China, and Caspian region, east Asia each winter season without any break. As such the extinction of ponds in Haryana directly threatens global avian biodiversity.

Passive acoustic monitoring using a towed hydrophone array results in identification of a previously unknown beaked whale habitat.

Science.gov (United States)

Yack, Tina M; Barlow, Jay; Calambokidis, John; Southall, Brandon; Coates, Shannon

2013-09-01

Beaked whales are diverse and species rich taxa. They spend the vast majority of their time submerged, regularly diving to depths of hundreds to thousands of meters, typically occur in small groups, and behave inconspicuously at the surface. These factors make them extremely difficult to detect using standard visual survey methods. However, recent advancements in acoustic detection capabilities have made passive acoustic monitoring (PAM) a viable alternative. Beaked whales can be discriminated from other odontocetes by the unique characteristics of their echolocation clicks. In 2009 and 2010, PAM methods using towed hydrophone arrays were tested. These methods proved highly effective for real-time detection of beaked whales in the Southern California Bight (SCB) and were subsequently implemented in 2011 to successfully detect and track beaked whales during the ongoing Southern California Behavioral Response Study. The three year field effort has resulted in (1) the successful classification and tracking of Cuvier's (Ziphius cavirostris), Baird's (Berardius bairdii), and unidentified Mesoplodon beaked whale species and (2) the identification of areas of previously unknown beaked whale habitat use. Identification of habitat use areas will contribute to a better understanding of the complex relationship between beaked whale distribution, occurrence, and preferred habitat characteristics on a relatively small spatial scale. These findings will also provide information that can be used to promote more effective management and conservation of beaked whales in the SCB, a heavily used Naval operation and training region.

Many routes leading to Rome: Potential causes for the multi-route migration system of Red Knots Calidris canutus islandica

NARCIS (Netherlands)

Bauer, S.; Ens, B.J.; Klaassen, M.R.J.

2010-01-01

Migrants, such as birds or representatives of other taxa, usually make use of several stopover sites to cover the distance between their site of origin and destination. Potentially, multiple routes exist, but often little is known about the causes and consequences of alternative migration routes.

Bird diversity and distribution in relation to urban landscape types in northern Rwanda.

Science.gov (United States)

Gatesire, T; Nsabimana, D; Nyiramana, A; Seburanga, J L; Mirville, M O

2014-01-01

Using the point count method, linear mixed models, Shannon's diversity index, and Bray-Curtis cluster analysis, we conducted a study of the effect of urban fabric layout on bird diversity and distribution in northern Rwanda. The results showed a significant effect of city landscapes on bird richness and relative abundance; residential neighborhoods, institutional grounds, and informal settlements had the highest species diversity in comparison to other microlandscape types. Riversides were characterized by specialized bird species, commonly known to be restricted to wetland environments. Built-up areas and open field landscapes had comparable results. One Albertine Rift endemic bird species, the Ruwenzori Double-collared Sunbird (Cinnyris stuhlmanni), was recorded. Three migratory birds were found in Musanze city for the first time: the Common Sandpiper (Actitis hypoleucos), the Spotted Flycatcher (Muscicapa striata), and the Willow Warbler (Phylloscopus trochilus). Two bird species have not been previously reported in Rwanda: the Garden Warbler (Sylvia borin) and the Lesser Spotted Eagle (Aquila pomarina). The implications of this study are particularly relevant to urban decision makers who should consider the existence of a great diversity of avian fauna when developing and implementing master plans, especially when villages and cities are in proximity of protected areas or natural reserves.

Diversity and abundance of water birds in a subarctic lake during three decades

Directory of Open Access Journals (Sweden)

Anders Klemetsen

2013-12-01

Full Text Available The numbers of divers, ducks, gulls, terns and waders in the 15 km2 oligotrophic lake Takvatn, North Norway were estimated six times during 1983-2012. Systematic mapping surveys were done by boat within the first week after ice-break in June. Twenty-one species were observed over the years and 12 were regarded as breeding on the lake. Red-breasted merganser Mergus serrator was the dominant diving bird, with estimated minimum number of pairs varying from 15 to 39 among years. Black-throated diver Gavia arctica (1-3 pairs, tufted duck Aythya fuligula (2-15 pairs and common scoter Melanitta nigra (1-5 pairs bred regularly, while velvet scoter Melanitta fusca (1-2 and goldeneye Bucephala clangula (2-4 were found in some years and mallard Anas platyrhynchos (1 pair and wigeon Anas penelope (1 pair in one year. Common gull Larus canus (6-30 pairs and arctic tern Sterna paradisaea (2-35 pairs bred in all years. Common sandpiper Tringa hypoleucos (3-9 pairs and redshank Tringa totanus (1-4 pairs were regular waders. Density variations of mergansers, gulls and terns are possibly related to density variations of three-spined sticklebacks Gasterosteus aculeatus, their dominant fish prey. The water birds are important links in the food web of the lake.

Hellsgate Winter Range Mitigation Project; Long-term Management Plan, Project Report 1993, Final Draft.

Energy Technology Data Exchange (ETDEWEB)

Berger, Matthew T.

1994-01-01

A study was conducted on the Hellsgate Winter Range Mitigation Project area, a 4,943 acre ranch purchased for mitigating some habitat losses associated with the original construction of Grand Coulee Dam and innundation of habitat by Lake Roosevelt. A Habitat Evaluation Procedure (HEP) study was used to determine habitat quality and quantity baseline data and future projections. Target species used in the study were sharp-tailed grouse (Tympanuchus phasianellus), mule deer (Odocoileus hemoinus), mink (Mustela vison), spotted sandpiper (Actiius colchicus), bobcat (Felis reufs), blue grouse (Dendragapus obscurus), and mourning dove (Zenaida macroura). From field data collected, limiting life values or HSI's (Habitat Suitability Index's) for each indicator species was determined for existing habitats on project lands. From this data a long term management plan was developed. This report is designed to provide guidance for the management of project lands in relation to the habitat cover types discussed and the indicator species used to evaluate these cover types. In addition, the plan discusses management actions, habitat enhancements, and tools that will be used to enhance, protect and restore habitats to desired conditions. Through planned management actions biodiversity and vegetative structure can be optimized over time to reduce or eliminate, limiting HSI values for selected wildlife on project lands.

A review of the reproductive biology and breeding management of tapirs.

Science.gov (United States)

Pukazhenthi, Budhan; Quse, Viviana; Hoyer, Mark; van Engeldorp Gastelaars, Heleen; Sanjur, Oris; Brown, Janine L

2013-03-01

Tapirs (Tapirus sp.) have been studied extensively in the wild, yet little is known about their fundamental reproductive biology, information that is critical to establishing self-sustaining populations in captivity as a hedge against extinction. This paper reviews information on the reproductive biology of the 4 species of tapirs: Baird's (Tapirus bairdii), lowland (T terrestris), mountain (T pinchaque) and Malayan (T indicus). Both sexes reach puberty between 14 and 48 months of age. Behaviorally, tapirs display few overt signs of estrus, and external signs of pregnancy are not evident until approximately 2 months before parturition. Immunoassay techniques to measure reproductive hormones in blood and urine have been validated for tapirs, which allow monitoring of ovarian cycle activity and pregnancy. Data indicate that females are polyestrous, with an estrous cycle length of approximately 30 days. The exception is the Malayan tapir, which exhibits 2 types of cycles: short (approximately 1 month) and long (approximately 2 months). Gestation length is approximately 13 months and females can conceive at the first post-partum cycle within 1 month after birth. Good quality ejaculates have been obtained via electroejaculation in the Baird's and Malayan tapir and the sperm from Baird's tapir cryopreserved using standard cryodiluents, although more work is needed to optimize these protocols. Given that all 4 species of tapir most likely will continue to be maintained in captivity, effective genetic management is vital for long-term survival. Optimization of assisted reproductive technologies, including sperm cryopreservation and artificial insemination, could benefit the genetic management of tapirs. © 2012 Wiley Publishing Asia Pty Ltd, ISZS and IOZ/CAS.

Domesticating nature? Surveillance and conservation of migratory shorebirds in the "Atlantic Flyway".

Science.gov (United States)

Whitney, Kristoffer

2014-03-01

Using a recent environmental controversy on the U.S. east coast over the conservation of red knots (Calidris canutus rufa) as a lens, I present a history of North American efforts to understand and conserve migratory shorebirds. Focusing on a few signal pieces of American legislation and their associated bureaucracies, I show the ways in which migratory wildlife have been thoroughly enrolled in efforts to quantify and protect their populations. Interactions between wildlife biologists and endangered species have been described by some scholars as "domestication"-a level of surveillance and intervention into nonhuman nature that constitutes a form of dependence. I pause to reflect on this historical trajectory, pointing out the breaks and continuities with older forms of natural history. Using the oft-mobilized Foucauldian metaphor of the panopticon as a foil, I question the utility and ethics of too-easily declaring "domesticated" wildlife an act of "biopower." Instead, I argue that Jacob von Uexküll's "umwelt" from early ecology and ethology, and more contemporary Science and Technology Studies (STS) analyses emphasizing multiple ontologies, offer more illuminating accounts of endangered species science. Neither science, conservation, nor history are well-served by the conflation of wildlife "surveillance" with the language of Foucauldian discipline. Copyright © 2013 Elsevier Ltd. All rights reserved.

Toxin constraint explains diet choice, survival and population dynamics in a molluscivore shorebird.

Science.gov (United States)

van Gils, Jan A; van der Geest, Matthijs; Leyrer, Jutta; Oudman, Thomas; Lok, Tamar; Onrust, Jeroen; de Fouw, Jimmy; van der Heide, Tjisse; van den Hout, Piet J; Spaans, Bernard; Dekinga, Anne; Brugge, Maarten; Piersma, Theunis

2013-07-22

Recent insights suggest that predators should include (mildly) toxic prey when non-toxic food is scarce. However, the assumption that toxic prey is energetically as profitable as non-toxic prey misses the possibility that non-toxic prey have other ways to avoid being eaten, such as the formation of an indigestible armature. In that case, predators face a trade-off between avoiding toxins and minimizing indigestible ballast intake. Here, we report on the trophic interactions between a shorebird (red knot, Calidris canutus canutus) and its two main bivalve prey, one being mildly toxic but easily digestible, and the other being non-toxic but harder to digest. A novel toxin-based optimal diet model is developed and tested against an existing one that ignores toxin constraints on the basis of data on prey abundance, diet choice, local survival and numbers of red knots at Banc d'Arguin (Mauritania) over 8 years. Observed diet and annual survival rates closely fit the predictions of the toxin-based model, with survival and population size being highest in years when the non-toxic prey is abundant. In the 6 of 8 years when the non-toxic prey is not abundant enough to satisfy the energy requirements, red knots must rely on the toxic alternative.

Basal metabolic rate and the mass of tissues differing in metabolic scope : Migration-related covariation between individual knots Calidris canutus

NARCIS (Netherlands)

Weber, TP; Piersma, T; Weber, Thomas P.

To examine whether variability in the basal metabolic rate (BMR) of migrant shorebirds is a function of a variably sized metabolic machinery or of temporal changes in metabolic intensities at the tissue level, BMR, body composition and activity of cytochrome-c oxidase (CCO, a marker for maximum

The effect of wind turbines on the bird population at Blyth Harbour

International Nuclear Information System (INIS)

Still, D.; Little, B.; Lawrence, S.

1996-01-01

Bird monitoring was carried out at Blyth Harbour Wind Farm which consists of a line of nine 300kW wind turbines distributed at 200m intervals along a 1.2km breakwater. The harbour breakwater is designated as part of a Site of Special Scientific Interest as it supports an internationally important winter population of Purple Sandpipers. The Blyth estuary is to be designated as part of a Special Protection Area under the EC Habitats Directive and as part of a proposed RAMSAR site due to its peak periods up to c.5000 bird movements/day occur adjacent to the windfarm. Mortality surveys (at one week intervals) were carried out on adjacent beaches to the wind farm in order to assess the background numbers of bird corpses and locate wind farm casualties. Supplementary mortality searches were carried out near power lines less than 2.5 km upstream from the wind farm. Tests of the efficiency of the mortality surveys have been carried out in order to assess the likely impact on the local bird populations. In spite of the large bird population supported by the harbour and its close proximity to the wind farm there have been relatively few collision victims (31) since the windfarm was commissioned. This is equivalent to less than 1.34 bird strike/wind turbine per annum. (author)

Interactions between terrestrial mammals and the fruits of two neotropical rainforest tree species

Science.gov (United States)

Camargo-Sanabria, Angela A.; Mendoza, Eduardo

2016-05-01

Mammalian frugivory is a distinctive biotic interaction of tropical forests; however, most efforts in the Neotropics have focused on cases of animals foraging in the forest canopy, in particular primates and bats. In contrast much less is known about this interaction when it involves fruits deposited on the forest floor and terrestrial mammals. We conducted a camera-trapping survey to analyze the characteristics of the mammalian ensembles visiting fruits of Licania platypus and Pouteria sapota deposited on the forest floor in a well preserved tropical rainforest of Mexico. Both tree species produce large fruits but contrast in their population densities and fruit chemical composition. In particular, we expected that more species of terrestrial mammals would consume P. sapota fruits due to its higher pulp:seed ratio, lower availability and greater carbohydrate content. We monitored fruits at the base of 13 trees (P. sapota, n = 4 and L. platypus, n = 9) using camera-traps. We recorded 13 mammal species from which we had evidence of 8 consuming or removing fruits. These eight species accounted for 70% of the species of mammalian frugivores active in the forest floor of our study area. The ensemble of frugivores associated with L. platypus (6 spp.) was a subset of that associated with P. sapota (8 spp). Large body-sized species such as Tapirus bairdii, Pecari tajacu and Cuniculus paca were the mammals more frequently interacting with fruits of the focal species. Our results further our understanding of the characteristics of the interaction between terrestrial mammalian frugivores and large-sized fruits, helping to gain a more balanced view of its importance across different tropical forests and providing a baseline to compare against defaunated forests.

Congener Patterns of Persistent Organic Pollutants Establish the Extent of Contaminant Biotransport by Pacific Salmon in the Great Lakes.

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Gerig, Brandon S; Chaloner, Dominic T; Janetski, David J; Rediske, Richard R; O'Keefe, James P; Moerke, Ashley H; Lamberti, Gary A

2016-01-19

In the Great Lakes, introduced Pacific salmon (Oncorhynchus spp.) can transport persistent organic pollutants (POPs), such as polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs), to new environments during their spawning migrations. To explore the nature and extent of POP biotransport by salmon, we compared 58 PCB and 6 PBDE congeners found in spawning salmon directly to those in resident stream fish. We hypothesized that stream fish exposed to salmon spawners would have congener patterns similar to those of salmon, the presumed contaminant source. Using permutational multivariate analysis of variance (PERMANOVA) and nonmetric multidimensional scaling (NMDS), we found that POP congener patterns of Pacific salmon varied among regions in the Great Lakes basin (i.e., Lake Huron, Lake Michigan, or Lake Superior), tissue type (whole fish or eggs), and contaminant type (PCB or PBDE). For stream-resident fish, POP congener pattern was influenced by the presence of salmon, location (i.e., Great Lakes Basin), and species identity (i.e., brook trout [Salvelinus fontinalis] or mottled sculpin [Cottus bairdii]). Similarity in congener patterns indicated that salmon are a source of POPs to brook trout in stream reaches receiving salmon spawners from Lake Michigan and Lake Huron but not from Lake Superior. Congener patterns of mottled sculpin differed from those of brook trout and salmon, suggesting that brook trout and mottled sculpin either use salmon tissue to differing degrees, acquire POPs from different dietary sources, or bioaccumulate or metabolize POPs differently. Overall, our analyses identified the important role of salmon in contaminant biotransport but also demonstrated that the extent of salmon-mediated POP transfer and uptake in Great Lakes tributaries is location- and species-specific.

Phylogeography and spatial structure of the lowland tapir (Tapirus terrestris, Perissodactyla: Tapiridae) in South America.

Science.gov (United States)

Ruiz-García, Manuel; Vásquez, Catalina; Sandoval, Sergio; Kaston, Franz; Luengas-Villamil, Kelly; Shostell, Joseph Mark

2016-07-01

We sequenced the mitochondrial cytochrome b gene of 141 lowland tapirs (Tapirus terrestris) - representing the largest geographical distribution sample of this species studied across of South America to date. We compare our new data regard to two previous works on population structure and molecular systematics of T. terrestris. Our data agree with the Thoisy et al.'s work in (1) the Northern Western Amazon basin was the area with the highest gene diversity levels in T. terrestris, being probably the area of initial diversification; (2) there was no clear association between haplogroups and specific geographical areas; (3) there were clear population decreases during the last glacial maximum for the different haplogroups detected, followed by population expansions during the Holocene; and (4) our temporal splits among different T. terrestris haplogroups coincided with the first molecular clock approach carried out by these authors (fossil calibration). Nevertheless, our study disagreed regard to other aspects of the Thoisy et al.'s claims: (1) meanwhile, they detected four relevant clades in their data, we put forward six different relevant clades; (2) the Amazon River was not a strong barrier for haplotype dispersion in T. terrestris; and (3) we found reciprocal monophyly between T. terrestris and T. pinchaque. Additionally, we sequenced 42 individuals (T. terrestris, T. pinchaque, T. bairdii, and the alleged "new species", T. kabomani) for three concatenated mitochondrial genes (Cyt-b, COI, and COII) agreeing quite well with the view of Voss et al., and against of the claims of Cozzuol et al. Tapirus kabomani should be not considered as a full species with the results obtained throughout the mitochondrial sequences.

Rapid ongoing decline of Baird's tapir in Cusuco National Park, Honduras.

Science.gov (United States)

McCANN, Niall P; Wheeler, Phil M; Coles, Tim; Bruford, Michael W

2012-12-01

During the International Tapir Symposium 16-21 Oct 2011, the conservation of Baird's tapir (Tapirus bairdii) in Honduras received a boost with the signing of a memorandum of understanding between the Minister Director of the Honduran Institute of Conservation and Forestry (ICF) and the Tapir Specialist Group (TSG). Despite this agreement, accelerating levels of hunting and habitat loss continue to pose a threat to Baird's tapir in Honduras. An ongoing study in Cusuco National Park in northwestern Honduras has been monitoring changes in population dynamics of Baird's tapir since 2006 through the collection of occupancy data. The study has identified an increase in hunting pressure, coinciding with a drastic decline in the encounter rate with Baird's tapir spoor. Here, we examine the significance of a range of demographic variables on Baird's tapir occupancy in Cusuco National Park using the software PRESENCE, and simulate the effects of different management strategies on the future dynamics of the population using the stochastic simulation software VORTEX. The predictions of the theoretical population models are compared to observed changes in occupancy levels. We found that non-intervention resulted in the local extinction of Baird's tapir within a very short time frame, but that various intervention models enabled the population to recover to near carrying capacity. Occupancy and extinction probability were shown to respond markedly to the increase in hunting pressure; and occupancy models supported the future population predictions generated by VORTEX. Our study suggests that immediate intervention is required to reduce hunting pressure to near historical levels to prevent the imminent local extinction of the species. © 2012 Wiley Publishing Asia Pty Ltd, ISZS and IOZ/CAS.

Novel avian paramyxovirus (APMV-15 isolated from a migratory bird in South America.

Directory of Open Access Journals (Sweden)

Luciano Matsumiya Thomazelli

Full Text Available A novel avian paramyxovirus (APMV isolated from a migratory bird cloacal swab obtained during active surveillance in April 2012 in the Lagoa do Peixe National Park, Rio Grande do Sul state, South of Brazil was biologically and genetically characterized. The nucleotide sequence of the full viral genome was completed using a next-generation sequencing approach. The genome was 14,952 nucleotides (nt long, with six genes (3'-NP-P-M-F-HN-L-5' encoding 7 different proteins, typical of APMV. The fusion (F protein gene of isolate RS-1177 contained 1,707 nucleotides in a single open reading frame encoding a protein of 569 amino acids. The F protein cleavage site contained two basic amino acids (VPKER↓L, typical of avirulent strains. Phylogenetic analysis of the whole genome indicated that the virus is related to APMV-10, -2 and -8, with 60.1% nucleotide sequence identity to the closest APMV-10 virus, 58.7% and 58.5% identity to the closest APMV-8 and APMV-2 genome, respectively, and less than 52% identity to representatives of the other APMVs groups. Such distances are comparable to the distances observed among other previously identified APMVs serotypes. These results suggest that unclassified/calidris_fuscicollis/Brazil/RS-1177/2012 is the prototype strain of a new APMV serotype, APMV-15.

Shellfish dredging pushes a flexible avian top predator out of a marine protected area.

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Jan A van Gils

2006-11-01

Full Text Available There is a widespread concern about the direct and indirect effects of industrial fisheries; this concern is particularly pertinent for so-called "marine protected areas" (MPAs, which should be safeguarded by national and international law. The intertidal flats of the Dutch Wadden Sea are a State Nature Monument and are protected under the Ramsar convention and the European Union's Habitat and Birds Directives. Until 2004, the Dutch government granted permission for ~75% of the intertidal flats to be exploited by mechanical dredgers for edible cockles (Cerastoderma edule. Here we show that dredged areas belonged to the limited area of intertidal flats that were of sufficient quality for red knots (Calidris canutus islandica, a long-distance migrant molluscivore specialist, to feed. Dredging led to relatively lower settlement rates of cockles and also reduced their quality (ratio of flesh to shell. From 1998 to 2002, red knots increased gizzard mass to compensate for a gradual loss in shellfish quality, but this compensation was not sufficient and led to decreases in local survival. Therefore, the gradual destruction of the necessary intertidal resources explains both the loss of red knots from the Dutch Wadden Sea and the decline of the European wintering population. This study shows that MPAs that do not provide adequate protection from fishing may fail in their conservation objectives.

Trigo duro: comportamento de genótipos no estado de São Paulo Durum wheat: evaluation of genotypes for the state of São Paulo, Brazil

Directory of Open Access Journals (Sweden)

Carlos Eduardo de Oliveira Camargo

1995-01-01

Full Text Available Compararam-se 25 linhagens de trigo duro (Triticum durum L., um cultivar de triticale (X Triticosecale Wittmack e quatro cultivares de trigo (T. aestivum L. em seis experimentos em condição de irrigação por aspersão, analisando-se a produção de grãos, características agronômicas e resistência às doenças. As linhagens de trigo duro 14 (61150/Leeds//Gallo "S"/3/Garza "S"/4/Mexicali "S"/5/S-15-Crane "S", 21 (Boyeros "S"/Cocorit-71/5/Crane "S"/Ganso "S"//Marte "S"/3/Tildillo "S"/4/Memo "S", 25 (Gallareta "S" e 8 (Gediz "S"/Yavaros "S", de porte baixo a médio, foram resistentes às ferrugens-do-colmo (com exceção da 21 e da-folha, moderadamente resistentes ao oídio, suscetíveis à mancha foliar, e destacaram-se quanto à produção de grãos em solos com baixa acidez, não diferindo nem do trigo comum IAC-60, o mais cultivado atualmente no Estado de São Paulo, nem do triticale Álamos. Em condições de campo, a linhagem de trigo duro 19 (Mindum/Kingfisher "S"//Sandpiper apresentou imunidade às ferrugens-do-colmo e da-folha e foi moderadamente resistente ao oídio. O triticale Álamos e o trigo comum IAC-29 foram imunes ao oídio. Todos os genótipos avaliados foram altamente suscetíveis à mancha foliar, com exceção da linhagem 6 (Dackiye/Gerardo Vezio 394, moderadamente resistente.Twenty-five durum wheat (Triticum durum L. lines, one triticale (X Triticosecale Wittmack cultivar and four wheat (T aestivum L. cultivars were evaluated in six trials under sprinkler irrigation taking into account the grain yield, agronomic characteristics and disease resistance. The durum wheat lines 14 (61150/Leeds//Gallo "S"/3/Garza "S"/4/Mexicali "S"/5/S-15-Crane "S", 21 (Boyeros "S"/Cocorit-71/5/Crane "S"/Ganso "S"//Marte "S"/3/Tildillo "S"/4/Memo "S", 25 (Gallareta "S" and 8 (Gediz "S"/Yavaros "S", showed the following traites: resistant to stem and leaf rusts; moderately resistant to powdery mildew; susceptible to leaf spot, and short to

Captive and free-living red knots Calidris canutus exhibit differences in non-induced immunity that suggest different immune strategies in different environments

NARCIS (Netherlands)

Buehler, Deborah M.; Piersma, Theunis; Tieleman, B. Irene

Experiments on captive animals, in which conditions can be controlled, are useful for examining complex biological phenomena such as immune function. Such experiments have increased our understanding of immune responses in the context of trade-offs and pathogen pressure. However, few studies have

A three-dimensional morphometric analysis of upper forelimb morphology in the enigmatic tapir (Perissodactyla: Tapirus) hints at subtle variations in locomotor ecology.

Science.gov (United States)

MacLaren, Jamie A; Nauwelaerts, Sandra

2016-11-01

Forelimb morphology is an indicator for terrestrial locomotor ecology. The limb morphology of the enigmatic tapir (Perissodactyla: Tapirus) has often been compared to that of basal perissodactyls, despite the lack of quantitative studies comparing forelimb variation in modern tapirs. Here, we present a quantitative assessment of tapir upper forelimb osteology using three-dimensional geometric morphometrics to test whether the four modern tapir species are monomorphic in their forelimb skeleton. The shape of the upper forelimb bones across four species (T. indicus; T. bairdii; T. terrestris; T. pinchaque) was investigated. Bones were laser scanned to capture surface morphology and 3D landmark analysis was used to quantify shape. Discriminant function analyses were performed to reveal features which could be used for interspecific discrimination. Overall our results show that the appendicular skeleton contains notable interspecific differences. We demonstrate that upper forelimb bones can be used to discriminate between species (>91% accuracy), with the scapula proving the most diagnostic bone (100% accuracy). Features that most successfully discriminate between the four species include the placement of the cranial angle of the scapula, depth of the humeral condyle, and the caudal deflection of the olecranon. Previous studies comparing the limbs of T. indicus and T. terrestris are corroborated by our quantitative findings. Moreover, the mountain tapir T. pinchaque consistently exhibited the greatest divergence in morphology from the other three species. Despite previous studies describing tapirs as functionally mediportal in their locomotor style, we find osteological evidence suggesting a spectrum of locomotor adaptations in the tapirs. We conclude that modern tapir forelimbs are neither monomorphic nor are tapirs as conserved in their locomotor habits as previously described. J. Morphol. 277:1469-1485, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals

Informed renesting decisions: the effect of nest predation risk.

Science.gov (United States)

Pakanen, Veli-Matti; Rönkä, Nelli; Thomson, Robert L; Koivula, Kari

2014-04-01

Animals should cue on information that predicts reproductive success. After failure of an initial reproductive attempt, decisions on whether or not to initiate a second reproductive attempt may be affected by individual experience and social information. If the prospects of breeding success are poor, long-lived animals in particular should not invest in current reproductive success (CRS) in case it generates costs to future reproductive success (FRS). In birds, predation risk experienced during breeding may provide a cue for renesting success. Species having a high FRS potential should be flexible and take predation risk into account in their renesting decisions. We tested this prediction using breeding data of a long-lived wader, the southern dunlin Calidris alpina schinzii. As predicted, dunlin cued on predation risk information acquired from direct experience of nest failure due to predation and ambient nest predation risk. While the overall renesting rate was low (34.5%), the early season renesting rate was high but declined with season, indicating probable temporal changes in the costs and benefits of renesting. We develop a conceptual cost-benefit model to describe the effects of the phase and the length of breeding season on predation risk responses in renesting. We suggest that species investing in FRS should not continue breeding in short breeding seasons in response to predation risk but without time constraints, their response should be similar to species investing in CRS, e.g. within-season dispersal and increased nest concealment.

Seasonal variations in the diet and foraging behaviour of dunlins Calidris alpina in a south European estuary: improved feeding conditions for northward migrants.

Directory of Open Access Journals (Sweden)

Ricardo C Martins

Full Text Available During the annual cycle, migratory waders may face strikingly different feeding conditions as they move between breeding areas and wintering grounds. Thus, it is of crucial importance that they rapidly adjust their behaviour and diet to benefit from peaks of prey abundance, in particular during migration, when they need to accumulate energy at a fast pace. In this study, we compared foraging behaviour and diet of wintering and northward migrating dunlins in the Tagus estuary, Portugal, by video-recording foraging birds and analysing their droppings. We also estimated energy intake rates and analysed variations in prey availability, including those that were active at the sediment surface. Wintering and northward migrating dunlins showed clearly different foraging behaviour and diet. In winter, birds predominantly adopted a tactile foraging technique (probing, mainly used to search for small buried bivalves, with some visual surface pecking to collect gastropods and crop bivalve siphons. Contrastingly, in spring dunlins generally used a visual foraging strategy, mostly to consume worms, but also bivalve siphons and shrimps. From winter to spring, we found a marked increase both in the biomass of invertebrate prey in the sediment and in the surface activity of worms and siphons. The combination of these two factors, together with the availability of shrimps in spring, most likely explains the changes in the diet and foraging behaviour of dunlins. Northward migrating birds took advantage from the improved feeding conditions in spring, achieving 65% higher energy intake rates as compared with wintering birds. Building on these results and on known daily activity budgets for this species, our results suggest that Tagus estuary provides high-quality feeding conditions for birds during their stopovers, enabling high fattening rates. These findings show that this large wetland plays a key role as a stopover site for migratory waders within the East Atlantic Flyway.

Vulnerability of breeding waterbirds to climate change in the Prairie Pothole Region, U.S.A.

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Valerie Steen

Full Text Available The Prairie Pothole Region (PPR of the north-central U.S. and south-central Canada contains millions of small prairie wetlands that provide critical habitat to many migrating and breeding waterbirds. Due to their small size and the relatively dry climate of the region, these wetlands are considered at high risk for negative climate change effects as temperatures increase. To estimate the potential impacts of climate change on breeding waterbirds, we predicted current and future distributions of species common in the PPR using species distribution models (SDMs. We created regional-scale SDMs for the U.S. PPR using Breeding Bird Survey occurrence records for 1971-2011 and wetland, upland, and climate variables. For each species, we predicted current distribution based on climate records for 1981-2000 and projected future distributions to climate scenarios for 2040-2049. Species were projected to, on average, lose almost half their current habitat (-46%. However, individual species projections varied widely, from +8% (Upland Sandpiper to -100% (Wilson's Snipe. Variable importance ranks indicated that land cover (wetland and upland variables were generally more important than climate variables in predicting species distributions. However, climate variables were relatively more important during a drought period. Projected distributions of species responses to climate change contracted within current areas of distribution rather than shifting. Given the large variation in species-level impacts, we suggest that climate change mitigation efforts focus on species projected to be the most vulnerable by enacting targeted wetland management, easement acquisition, and restoration efforts.

Bird surveys at Stokes Point and Philips Bay, Yukon in 1983. No. 40

Energy Technology Data Exchange (ETDEWEB)

Dickson, D L; Dickson, H L; Aiudi, G M

1988-01-01

The distribution, abundance, and habitat preferences of birds were studied at Stokes Point, Phillips Bay and King Point in the northern Yukon in 1983. These data were gathered to assist in decisions about future development of a port to support marine drilling activities in the Beaufort Sea. Nesting bird densities at Stokes Point were similar to those found elsewhere on the Yukon Coastal Plain due to the similarity in habitat. The lagoon at Stokes Point was locally important to molting ducks. Several species occurred in higher densities at Phillips Bay than elsewhere on the Plain, mainly due to the deltas and spits created by rivers flowing into the Bay. These deltas were locally important to such species as molting non-breeding tundra swans, Canada geese, and ducks. During ground surveys in June, habitat was classified into 13 types and the nesting density for each bird species calculated for each habitat type. Overall bird densities were more than 3 times higher in lowland than in upland habitats. Passerine densities and species were highest in the tall shrub type of habitat found primarily in stream and river valleys. The Yukon Coastal Plain is an important nesting area for the stilt sandpiper, which has a limited breeding range. The Plain is also nationally important for nesting long-billed dowitchers and yellow wagtails, both fairly common in the study area but with very limited breeding distribution within Canada. The Plain is also internationally important to fall staging snow geese. 38 refs., 17 figs., 35 tabs.

Shorebird Migration Patterns in Response to Climate Change: A Modeling Approach

Science.gov (United States)

Smith, James A.

2010-01-01

The availability of satellite remote sensing observations at multiple spatial and temporal scales, coupled with advances in climate modeling and information technologies offer new opportunities for the application of mechanistic models to predict how continental scale bird migration patterns may change in response to environmental change. In earlier studies, we explored the phenotypic plasticity of a migratory population of Pectoral sandpipers by simulating the movement patterns of an ensemble of 10,000 individual birds in response to changes in stopover locations as an indicator of the impacts of wetland loss and inter-annual variability on the fitness of migratory shorebirds. We used an individual based, biophysical migration model, driven by remotely sensed land surface data, climate data, and biological field data. Mean stop-over durations and stop-over frequency with latitude predicted from our model for nominal cases were consistent with results reported in the literature and available field data. In this study, we take advantage of new computing capabilities enabled by recent GP-GPU computing paradigms and commodity hardware (general purchase computing on graphics processing units). Several aspects of our individual based (agent modeling) approach lend themselves well to GP-GPU computing. We have been able to allocate compute-intensive tasks to the graphics processing units, and now simulate ensembles of 400,000 birds at varying spatial resolutions along the central North American flyway. We are incorporating additional, species specific, mechanistic processes to better reflect the processes underlying bird phenotypic plasticity responses to different climate change scenarios in the central U.S.

Exposure of nonbreeding migratory shorebirds to cholinesterase-inhibiting contaminants in the western hemisphere

Science.gov (United States)

Strum, K.M.; Hooper, M.J.; Johnson, K.A.; Lanctot, Richard B.; Zaccagnini, M.E.; Sandercock, B.K.

2010-01-01

Migratory shorebirds frequently forage and roost in agricultural habitats, where they may be exposed to cholinesterase-inhibiting pesticides. Exposure to organophosphorus and carbamate compounds, common anti-cholinesterases, can cause sublethal effects, even death. To evaluate exposure of migratory shorebirds to organophosphorus and carbamates, we sampled birds stopping over during migration in North America and wintering in South America. We compared plasma cholinesterase activities and body masses of individuals captured at sites with no known sources of organophosphorus or carbamates to those captured in agricultural areas where agrochemicals were recommended for control of crop pests. In South America, plasma acetylcholinesterase and butyrylcholinesterase activity in Buff-breasted Sandpipers was lower at agricultural sites than at reference sites, indicating exposure to organophosphorus and carbamates. Results of plasma cholinesterase reactivation assays and foot-wash analyses were inconclusive. A meta-analysis of six species revealed no widespread effect of agricultural chemicals on cholinesterase activity. however, four of six species were negative for acetylcholinesterase and one of six for butyrylcholinesterase, indicating negative effects of pesticides on cholinesterase activity in a subset of shorebirds. Exposure to cholinesterase inhibitors can decrease body mass, but comparisons between treatments and hemispheres suggest that agrochemicals did not affect migratory shorebirds' body mass. Our study, one of the first to estimate of shorebirds' exposure to cholinesterase-inhibiting pesticides, suggests that shorebirds are being exposed to cholinesterase- inhibiting pesticides at specific sites in the winter range but not at migratory stopover sites. future research should examine potential behavioral effects of exposure and identify other potential sitesand levels of exposure. ?? The Cooper Ornithological Society 2010.

Stable isotope and pen feeding trial studies confirm the value of horseshoe crab Limulus polyphemus eggs to spring migrant shorebirds in Delaware Bay

Science.gov (United States)

Haramis, G.M.; Link, W.A.; Osenton, P.C.; Carter, Daniel B.; Weber, R.G.; Clark, N.A.; Teece, M.A.; Mizrahi, D.S.

2007-01-01

We used stable isotope (SI) methods in combination with pen feeding trials to determine the importance of eggs of the Atlantic horseshoe crab Limulus polyphemus to migratory fattening of red knots Calidris canutus rufa and ruddy turnstones Arenaria interpres morinella during spring stopover in Delaware Bay. By manifesting measurable fractionation (ca +3?) and rapid turnover, blood plasma *15 nitrogen proved a functional marker for SI diet tracking during the short 3-week stopover. Blood samples from free-ranging knots (3 data sets) and turnstones (1 data set) produced similar convergence of plasma *15 N signatures with increasing body mass that indicated highly similar diets. Asymptotes deviated slightly (0.3? to 0.7?) from that of captive shorebirds fed a diet of only crab eggs during stopover, thus confirming a strong crab egg-shorebird linkage. The plasma *15N crab-egg diet asymptote was enriched ca +4.5? and therefore readily discriminated from that of either blue mussels Mytilus edulis or coquina clams Donax variabilis, the most likely alternative prey of knots in Delaware Bay. Crab eggs were highly palatable to captive knots and turnstones which achieved rates of mass gain (3?11 g/d) comparable to that of free-ranging birds. Peak consumption rates during hyperphagic events were 23,940 and 19,360 eggs/bird/d, respectively. The empirical conversions of eggs consumed to body mass gained (5,017 eggs/g for knots and 4,320 eggs/g for turnstones) indicate the large quantities of crab eggs required for the maintenance of these shorebird populations during stopover.

Geographic variation in host fish use and larval metamorphosis for the endangered dwarf wedgemussel

Science.gov (United States)

White, Barbara (St. John); Ferreri, C. Paola; Lellis, William A.; Wicklow, Barry J.; Cole, Jeffrey C.

2017-01-01

Host fishes play a crucial role in survival and dispersal of freshwater mussels (Unionoida), particularly rare unionids at conservation risk. Intraspecific variation in host use is not well understood for many mussels, including the endangered dwarf wedgemussel (Alasmidonta heterodon) in the USA.Host suitability of 33 fish species for dwarf wedgemussel glochidia (larvae) from the Delaware and Connecticut river basins was tested in laboratory experiments over 9 years. Relative suitability of three different populations of a single host fish, the tessellated darter (Etheostoma olmstedi), from locations in the Connecticut, Delaware, and Susquehanna river basins, was also tested.Connecticut River basin A. heterodon metamorphosed into juvenile mussels on tessellated darter, slimy sculpin (Cottus cognatus), and Atlantic salmon (Salmo salar) parr. Delaware River basin mussels metamorphosed using these three species, as well as brown trout (Salmo trutta), banded killifish (Fundulus diaphanus), mottled sculpin (Cottus bairdii), striped bass (Morone saxatilis), and shield darter (Percina peltata). Atlantic salmon, striped bass, and sculpins were highly effective hosts, frequently generating 5+ juveniles per fish (JPF) and metamorphosis success (MS; proportion of attaching larvae that successfully metamorphose) ≥ 0.4, and producing juveniles in repeated trials.In experiments on tessellated darters, mean JPF and MS values decreased as isolation between the mussel source (Connecticut River) and each fish source increased; mean JPF = 10.45, 6.85, 4.14, and mean MS = 0.50, 0.41, and 0.34 in Connecticut, Delaware, and Susquehanna river darters, respectively. Host suitability of individual darters was highly variable (JPF = 2–11; MS = 0.20–1.0).The results show that mussel–host fish compatibility in A. heterodon differs among Atlantic coastal rivers, and suggest that hosts including anadromous Atlantic salmon and striped bass may help sustain A. heterodon in parts of

Winter body mass and over-ocean flocking as components of danger management by Pacific dunlins.

Science.gov (United States)

Ydenberg, Ronald C; Dekker, Dick; Kaiser, Gary; Shepherd, Philippa C F; Ogden, Lesley Evans; Rickards, Karen; Lank, David B

2010-01-21

We compared records of the body mass and roosting behavior of Pacific dunlins (Calidris alpina pacifica) wintering on the Fraser River estuary in southwest British Columbia between the 1970s and the 1990s. 'Over-ocean flocking' is a relatively safe but energetically-expensive alternative to roosting during the high tide period. Fat stores offer protection against starvation, but are a liability in escape performance, and increase flight costs. Peregrine falcons (Falco peregrinus) were scarce on the Fraser River estuary in the 1970s, but their numbers have since recovered, and they prey heavily on dunlins. The increase has altered the balance between predation and starvation risks for dunlins, and thus how dunlins regulate roosting behavior and body mass to manage the danger. We therefore predicted an increase in the frequency of over-ocean flocking as well as a decrease in the amount of fat carried by dunlins over these decades. Historical observations indicate that over-ocean flocking of dunlins was rare prior to the mid-1990s and became common thereafter. Residual body masses of dunlins were higher in the 1970s, with the greatest difference between the decades coinciding with peak peregrine abundance in October, and shrinking over the course of winter as falcon seasonal abundance declines. Whole-body fat content of dunlins was lower in the 1990s, and accounted for most of the change in body mass. Pacific dunlins appear to manage danger in a complex manner that involves adjustments both in fat reserves and roosting behavior. We discuss reasons why over-ocean flocking has apparently become more common on the Fraser estuary than at other dunlin wintering sites.

Investigating avian influenza infection hotspots in old-world shorebirds.

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Nicolas Gaidet

Full Text Available Heterogeneity in the transmission rates of pathogens across hosts or environments may produce disease hotspots, which are defined as specific sites, times or species associations in which the infection rate is consistently elevated. Hotspots for avian influenza virus (AIV in wild birds are largely unstudied and poorly understood. A striking feature is the existence of a unique but consistent AIV hotspot in shorebirds (Charadriiformes associated with a single species at a specific location and time (ruddy turnstone Arenaria interpres at Delaware Bay, USA, in May. This unique case, though a valuable reference, limits our capacity to explore and understand the general properties of AIV hotspots in shorebirds. Unfortunately, relatively few shorebirds have been sampled outside Delaware Bay and they belong to only a few shorebird families; there also has been a lack of consistent oropharyngeal sampling as a complement to cloacal sampling. In this study we looked for AIV hotspots associated with other shorebird species and/or with some of the larger congregation sites of shorebirds in the old world. We assembled and analysed a regionally extensive dataset of AIV prevalence from 69 shorebird species sampled in 25 countries across Africa and Western Eurasia. Despite this diverse and extensive coverage we did not detect any new shorebird AIV hotspots. Neither large shorebird congregation sites nor the ruddy turnstone were consistently associated with AIV hotspots. We did, however, find a low but widespread circulation of AIV in shorebirds that contrast with the absence of AIV previously reported in shorebirds in Europe. A very high AIV antibody prevalence coupled to a low infection rate was found in both first-year and adult birds of two migratory sandpiper species, suggesting the potential existence of an AIV hotspot along their migratory flyway that is yet to be discovered.

Dietary flexibility in three representative waterbirds across salinity and depth gradients in salt ponds of San Francisco Bay

Science.gov (United States)

Takekawa, John Y.; Miles, A.K.; Tsao-Melcer, D. C.; Schoellhamer, D.H.; Fregien, S.; Athearn, N.D.

2009-01-01

Salt evaporation ponds have existed in San Francisco Bay, California, for more than a century. In the past decade, most of the salt ponds have been retired from production and purchased for resource conservation with a focus on tidal marsh restoration. However, large numbers of waterbirds are found in salt ponds, especially during migration and wintering periods. The value of these hypersaline wetlands for waterbirds is not well understood, including how different avian foraging guilds use invertebrate prey resources at different salinities and depths. The aim of this study was to investigate the dietary flexibility of waterbirds by examining the population number and diet of three feeding guilds across a salinity and depth gradient in former salt ponds of the Napa-Sonoma Marshes. Although total invertebrate biomass and species richness were greater in low than high salinity salt ponds, waterbirds fed in ponds that ranged from low (20 g l-1) to very high salinities (250 g l -1). American avocets (surface sweeper) foraged in shallow areas at pond edges and consumed a wide range of prey types (8) including seeds at low salinity, but preferred brine flies at mid salinity (40-80 g l-1). Western sandpipers (prober) focused on exposed edges and shoal habitats and consumed only a few prey types (2-4) at both low and mid salinities. Suitable depths for foraging were greatest for ruddy ducks (diving benthivore) that consumed a wide variety of invertebrate taxa (5) at low salinity, but focused on fewer prey (3) at mid salinity. We found few brine shrimp, common in higher salinity waters, in the digestive tracts of any of these species. Dietary flexibility allows different guilds to use ponds across a range of salinities, but their foraging extent is limited by available water depths. ?? 2009 USGS, US Government.

Alaska North Slope National Energy Strategy initiative: Analysis of five undeveloped fields

International Nuclear Information System (INIS)

Thomas, C.P.; Allaire, R.B.; Doughty, T.C.; Faulder, D.D.; Irving, J.S.; Jamison, H.C.; White, G.J.

1993-05-01

The US Department of Energy was directed in the National Energy Strategy to establish a federal interagency task force to identify specific technical and regulatory barriers to the development of five undeveloped North Slope Alaska fields and make recommendations for their resolution. The five fields are West Sak, Point Thomson, Gwydyr Bay, Seal Island/Northstar, and Sandpiper Island. Analysis of environmental, regulatory, technical, and economic information, and data relating to the development potential of the five fields leads to the following conclusions: Development of the five fields would result in an estimated total of 1,055 million barrels of oil and 4.4 trillion cubic feet of natural gas and total investment of $9.4 billion in 1992 dollars. It appears that all five of the fields will remain economically marginal developments unless there is significant improvement in world oil prices. Costs of regulatory compliance and mitigation, and costs to reduce or maintain environmental impacts at acceptable levels influence project investments and operating costs and must be considered in the development decision making process. The development of three of the fields (West Sak, Point Thomson, and Gwydyr Bay) that are marginally feasible would have an impact on North Slope production over the period from about 2000 to 2014 but cannot replace the decline in Prudhoe Bay Unit production or maintain the operation of the Trans-Alaska Pipeline System (TAPS) beyond about 2014 with the assumption that the TAPS will shut down when production declines to the range of 400 to 200 thousand barrels of oil/day. Recoverable reserves left in the ground in the currently producing fields and soon to be developed fields, Niakuk and Point McIntyre, would range from 1 billion to 500 million barrels of oil corresponding to the time period of 2008 to 2014 based on the TAPS shutdown assumption

Alaska North Slope National Energy Strategy initiative: Analysis of five undeveloped fields

Energy Technology Data Exchange (ETDEWEB)

Thomas, C.P.; Allaire, R.B.; Doughty, T.C.; Faulder, D.D.; Irving, J.S.; Jamison, H.C.; White, G.J.

1993-05-01

The US Department of Energy was directed in the National Energy Strategy to establish a federal interagency task force to identify specific technical and regulatory barriers to the development of five undeveloped North Slope Alaska fields and make recommendations for their resolution. The five fields are West Sak, Point Thomson, Gwydyr Bay, Seal Island/Northstar, and Sandpiper Island. Analysis of environmental, regulatory, technical, and economic information, and data relating to the development potential of the five fields leads to the following conclusions: Development of the five fields would result in an estimated total of 1,055 million barrels of oil and 4.4 trillion cubic feet of natural gas and total investment of $9.4 billion in 1992 dollars. It appears that all five of the fields will remain economically marginal developments unless there is significant improvement in world oil prices. Costs of regulatory compliance and mitigation, and costs to reduce or maintain environmental impacts at acceptable levels influence project investments and operating costs and must be considered in the development decision making process. The development of three of the fields (West Sak, Point Thomson, and Gwydyr Bay) that are marginally feasible would have an impact on North Slope production over the period from about 2000 to 2014 but cannot replace the decline in Prudhoe Bay Unit production or maintain the operation of the Trans-Alaska Pipeline System (TAPS) beyond about 2014 with the assumption that the TAPS will shut down when production declines to the range of 400 to 200 thousand barrels of oil/day. Recoverable reserves left in the ground in the currently producing fields and soon to be developed fields, Niakuk and Point McIntyre, would range from 1 billion to 500 million barrels of oil corresponding to the time period of 2008 to 2014 based on the TAPS shutdown assumption.

Concentrations of 17 elements, including mercury, in the tissues, food and abiotic environment of Arctic shorebirds.

Science.gov (United States)

Hargreaves, Anna L; Whiteside, Douglas P; Gilchrist, Grant

2011-09-01

Exposure to contaminants is one hypothesis proposed to explain the global decline in shorebirds, and is also an increasing concern in the Arctic. We assessed potential contaminants (As, Be, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Sb, Se, Tl, V, and Zn) at a shorebird breeding site in Nunavut, Canada. We compared element levels in soil, invertebrates and shorebird blood to assess evidence for bioconcentration and biomagnification within the Arctic-based food chain. We tested whether elements in blood, feathers and eggs of six shorebird species (Pluvialis squatarola, Calidris alpina, C. fuscicollis, Phalaropus fulicarius, Charadrius semipalmatus, and Arenaria interpres) were related to fitness endpoints: adult body condition, blood-parasite load, egg size, eggshell thickness, nest duration, and hatching success. To facilitate comparison to other sites, we summarise the published data on toxic metals in shorebird blood and egg contents. Element concentrations and invertebrate composition differed strongly among habitats, and habitat use and element concentrations differed among shorebird species. Hg, Se, Cd, Cu, and Zn bioconcentrated from soil to invertebrates, and Hg, Se and Fe biomagnified from invertebrates to shorebird blood. As, Ni, Pb, Co and Mn showed significant biodilution from soil to invertebrates to shorebirds. Soil element levels were within Canadian guidelines, and invertebrate Hg levels were below dietary levels suggested for the protection of wildlife. However, maximum Hg in blood and eggs approached levels associated with toxicological effects and Hg-pollution in other bird species. Parental blood-Hg was negatively related to egg volume, although the relationship varied among species. No other elements approached established toxicological thresholds. In conclusion, whereas we found little evidence that exposure to elements at this site is leading to the declines of the species studied, Hg, as found elsewhere in the Canadian Arctic, is of potential

An evaluation of intertidal feeding habitats from a shorebird perspective: Towards relevant comparisons between temperate and tropical mudflats

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Piersma, Theunis; de Goeij, Petra; Tulp, Ingrid

Macrozoobenthic communities of intertidal soft sediments are reviewed worldwide from the perspective of a mollusc-eating shorebird species. Based on 19 sites, total biomass figures varied between 5 and 80 g AFDM per m 2 (average 24 g AFDM per m 2); no latitudinal trends are apparent. The contribution made by bivalves and gastropods varies between 1% and 99%, north-temperate intertidal flats having relatively more molluscs than tropical flats. Intertidal flats in the tropics contain a greater variety of taxa, with brachiopods in Indonesia and echinoderms in northwest Australia contributing significantly to biomass only there. Limits to the occurrence of avian predators of intertidal benthos are set by the harvestable fraction of the biomass on offer and the costs of living at a particular site. No systematic differences in the harvestable fraction of the total mollusc-biomass for a worldwide occurring shorebird species specializing on molluscs (knots Calidris canutus) were apparent between temperate and tropical intertidal areas, in spite of large differences in maintenance metabolism incurred by these birds. The harvestable fractions of bivalves in the two West African areas (Banc d'Arguin, Mauritania and Guinea-Bissau) tended to be high (23-84% of total biomass in six species), they were relatively low (2-52% in five species) in the temperate Wadden Sea and the tropical northwest Australian site. Harvestable biomass determines the intake rate of shorebirds, as illustrated by functional-response curves of knots feeding on two bivalves species. We argue that the collection of information on size-depth relationships along with faunal and biomass surveys at a range of sites is bound to greatly increase our understanding of both the biology of tidal-flat invertebrates and the resource base underpinning the spectacular seasonal migrations of shorebirds.

Winter body mass and over-ocean flocking as components of danger management by Pacific dunlins

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Ogden Lesley

2010-01-01

Full Text Available Abstract Background We compared records of the body mass and roosting behavior of Pacific dunlins (Calidris alpina pacifica wintering on the Fraser River estuary in southwest British Columbia between the 1970s and the 1990s. 'Over-ocean flocking' is a relatively safe but energetically-expensive alternative to roosting during the high tide period. Fat stores offer protection against starvation, but are a liability in escape performance, and increase flight costs. Peregrine falcons (Falco peregrinus were scarce on the Fraser River estuary in the 1970s, but their numbers have since recovered, and they prey heavily on dunlins. The increase has altered the balance between predation and starvation risks for dunlins, and thus how dunlins regulate roosting behavior and body mass to manage the danger. We therefore predicted an increase in the frequency of over-ocean flocking as well as a decrease in the amount of fat carried by dunlins over these decades. Results Historical observations indicate that over-ocean flocking of dunlins was rare prior to the mid-1990s and became common thereafter. Residual body masses of dunlins were higher in the 1970s, with the greatest difference between the decades coinciding with peak peregrine abundance in October, and shrinking over the course of winter as falcon seasonal abundance declines. Whole-body fat content of dunlins was lower in the 1990s, and accounted for most of the change in body mass. Conclusions Pacific dunlins appear to manage danger in a complex manner that involves adjustments both in fat reserves and roosting behavior. We discuss reasons why over-ocean flocking has apparently become more common on the Fraser estuary than at other dunlin wintering sites.

When the seasons don't fit: speedy molt as a routine carry-over cost of reproduction.

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Maurine W Dietz

Full Text Available The failure of animals to fit all life-cycle stages into an annual cycle could reduce the chances of successful breeding. In some cases, non-optimal strategies will be adopted in order to maintain the life-cycle within the scope of one year. We studied trade-offs made by a High Arctic migrant shorebird, the red knot Calidris canutus islandica, between reproduction and wing feather molt carried out in the non-breeding period in the Dutch Wadden Sea. We compared primary molt duration between birds undertaking the full migratory and breeding schedule with birds that forego breeding because they are young or are maintained in captivity. Molt duration was ca. 71 days in breeding adults, which was achieved by an accelerated feather replacement strategy. Second-year birds and captive adults took ca. 22% and 27% longer, respectively. Second-year birds start molt in late June, more than four weeks before captive adults, and almost seven weeks before adults that return from breeding in late July-August. Adults finish molt in October when steeply increasing thermostatic costs and reductions in food availability occur. Primary molt duration was longer in female than in male knots (all ages, which was accordance with the somewhat larger body size of females. Since fast growth leads to lower quality feathers, the speedy wing molt shown by Arctic-breeding birds may represent a time constraint that is an unavoidable and routine cost of reproduction. So far it was hypothesized that only birds over 1 kg would have difficulty fitting molt within a year. Here we show that in birds an order of magnitude smaller, temporal imperatives may impose the adoption of non-optimal life-cycle routines in the entire actively breeding population.

When the seasons don't fit: speedy molt as a routine carry-over cost of reproduction.

Science.gov (United States)

Dietz, Maurine W; Rogers, Ken G; Piersma, Theunis

2013-01-01

The failure of animals to fit all life-cycle stages into an annual cycle could reduce the chances of successful breeding. In some cases, non-optimal strategies will be adopted in order to maintain the life-cycle within the scope of one year. We studied trade-offs made by a High Arctic migrant shorebird, the red knot Calidris canutus islandica, between reproduction and wing feather molt carried out in the non-breeding period in the Dutch Wadden Sea. We compared primary molt duration between birds undertaking the full migratory and breeding schedule with birds that forego breeding because they are young or are maintained in captivity. Molt duration was ca. 71 days in breeding adults, which was achieved by an accelerated feather replacement strategy. Second-year birds and captive adults took ca. 22% and 27% longer, respectively. Second-year birds start molt in late June, more than four weeks before captive adults, and almost seven weeks before adults that return from breeding in late July-August. Adults finish molt in October when steeply increasing thermostatic costs and reductions in food availability occur. Primary molt duration was longer in female than in male knots (all ages), which was accordance with the somewhat larger body size of females. Since fast growth leads to lower quality feathers, the speedy wing molt shown by Arctic-breeding birds may represent a time constraint that is an unavoidable and routine cost of reproduction. So far it was hypothesized that only birds over 1 kg would have difficulty fitting molt within a year. Here we show that in birds an order of magnitude smaller, temporal imperatives may impose the adoption of non-optimal life-cycle routines in the entire actively breeding population.

Stable Isotope Analysis Reveals That Agricultural Habitat Provides an Important Dietary Component for Nonbreeding Dunlin

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Lesley Joan Evans Ogden

2005-12-01

Full Text Available Although shorebirds spending the winter in temperate areas frequently use estuarine and supratidal (upland feeding habitats, the relative contribution of each habitat to individual diets has not been directly quantified. We quantified the proportional use that Calidris alpina pacifica (Dunlin made of estuarine vs. terrestrial farmland resources on the Fraser River Delta, British Columbia, using stable isotope analysis (δ13C, δ15N of blood from 268 Dunlin over four winters, 1997 through 2000. We tested for individual, age, sex, morphological, seasonal, and weather-related differences in dietary sources. Based on single- (δ13C and dual-isotope mixing models, the agricultural habitat contributed approximately 38% of Dunlin diet averaged over four winters, with the balance from intertidal flats. However, there was a wide variation among individuals in the extent of agricultural feeding, ranging from about 1% to 95% of diet. Younger birds had a significantly higher terrestrial contribution to diet (43% than did adults (35%. We estimated that 6% of adults and 13% of juveniles were obtaining at least 75% of their diet from terrestrial sources. The isotope data provided no evidence for sex or overall body size effects on the proportion of diet that is terrestrial in origin. The use of agricultural habitat by Dunlin peaked in early January. Adult Dunlin obtained a greater proportion of their diet terrestrially during periods of lower temperatures and high precipitation, whereas no such relationship existed for juveniles. Seasonal variation in the use of agricultural habitat suggests that it is used more during energetically stressful periods. The terrestrial farmland zone appears to be consistently important as a habitat for juveniles, but for adults it may provide an alternative feeding site used as a buffer against starvation during periods of extreme weather. Loss or reduction of agricultural habitat adjacent to estuaries may negatively impact

Risk evaluation for federally listed (roseate tern, piping plover) or candidate (red knot) bird species in offshore waters: A first step for managing the potential impacts of wind facility development on the Atlantic Outer Continental Shelf

Energy Technology Data Exchange (ETDEWEB)

Burger, Joanna [Division of Life Sciences, Rutgers University, Piscataway, NJ 08854-8082 (United States); Conserve Wildlife, 516 Farnsworth Avenue, Bordentown, NJ 08505 (United States); Gordon, Caleb; Newman, James; Forcey, Greg [Pandion Systems, Inc. 102 NE 10th Ave, Gainesville, FL 32601 (United States); Lawrence, J. [Conserve Wildlife, 516 Farnsworth Avenue, Bordentown, NJ 08505 (United States); Vlietstra, Lucy [Department of Science, US Coast Guard Academy, 27 Mohegan Drive, New London, CT 06320 (United States)

2011-01-15

With a worldwide increase in attention toward developing a reliance on renewable energy, there is a need to evaluate the effects of these facilities (solar, wind, hydropower) on ecosystems. We conduct a hazard and risk evaluation for three species of birds that are listed, or candidates for listing, as federally threatened or endangered in the US, and that might occur offshore on the Atlantic Outer Continental Shelf (AOCS) where wind power facilities could be developed. Our objectives were to: 1) provide conceptual models for exposure for each species, and 2) examine potential exposure and hazards of roseate tern (Sterna dougallii) and piping plover (Charadrius melodus, both federally endangered in the US) and red knot (Calidris canutus rufa, candidate species) in the AOCS. We used a weight-of-evidence approach to evaluate information from a review of technical literature. We developed conceptual models to examine the relative vulnerability of each species as a function of life stage and cycle (breeding, staging, migratory, wintering). These methods are useful for conducting environmental assessments when empirical data are insufficient for a full risk assessment. We determined that 1) Roseate terns are likely to be exposed to risk during the migratory and breeding season when they occur in the AOCS, as well as while staging. 2) Piping plovers are not likely to be at risk during the breeding season, but may be at risk during spring or fall migrations. Risk to this species is likely to be low from turbines located far from land as this species migrates mainly along the coast. 3) Red knots are potentially exposed to some risk during migration, especially long-distance migrants whose migratory routes take them over the AOCS. More information is required on exact spatio-temporal migration routes, flight altitudes (especially during ascent and descent), and behavioral avoidance of turbines by birds to ascertain their risk. (author)

The Effect of Digestive Capacity on the Intake Rate of Toxic and Non-Toxic Prey in an Ecological Context.

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Thomas Oudman

Full Text Available Digestive capacity often limits food intake rate in animals. Many species can flexibly adjust digestive organ mass, enabling them to increase intake rate in times of increased energy requirement and/or scarcity of high-quality prey. However, some prey species are defended by secondary compounds, thereby forcing a toxin limitation on the forager's intake rate, a constraint that potentially cannot be alleviated by enlarging digestive capacity. Hence, physiological flexibility may have a differential effect on intake of different prey types, and consequently on dietary preferences. We tested this effect in red knots (Calidris canutus canutus, medium-sized migratory shorebirds that feed on hard-shelled, usually mollusc, prey. Because they ingest their prey whole and crush the shell in their gizzard, the intake rate of red knots is generally constrained by digestive capacity. However, one of their main prey, the bivalve Loripes lucinalis, imposes a toxin constraint due to its symbiosis with sulphide-oxidizing bacteria. We manipulated gizzard sizes of red knots through prolonged exposure to hard-shelled or soft foods. We then measured maximum intake rates of toxic Loripes versus a non-toxic bivalve, Dosinia isocardia. We found that intake of Dosinia exponentially increased with gizzard mass, confirming earlier results with non-toxic prey, whereas intake of Loripes was independent of gizzard mass. Using linear programming, we show that this leads to markedly different expected diet preferences in red knots that try to maximize energy intake rate with a small versus a large gizzard. Intra- and inter-individual variation in digestive capacity is found in many animal species. Hence, the here proposed functional link with individual differences in foraging decisions may be general. We emphasize the potential relevance of individual variation in physiology when studying trophic interactions.

Avian BMR in marine and non-marine habitats: a test using shorebirds.

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Gutiérrez, Jorge S; Abad-Gómez, José M; Sánchez-Guzmán, Juan M; Navedo, Juan G; Masero, José A

2012-01-01

Basal metabolic rate (BMR) is closely linked to different habitats and way of life. In birds, some studies have noted that BMR is higher in marine species compared to those inhabiting terrestrial habitats. However, the extent of such metabolic dichotomy and its underlying mechanisms are largely unknown. Migratory shorebirds (Charadriiformes) offer a particularly interesting opportunity for testing this marine-non-marine difference as they are typically divided into two broad categories in terms of their habitat occupancy outside the breeding season: 'coastal' and 'inland' shorebirds. Here, we measured BMR for 12 species of migratory shorebirds wintering in temperate inland habitats and collected additional BMR values from the literature for coastal and inland shorebirds along their migratory route to make inter- and intraspecific comparisons. We also measured the BMR of inland and coastal dunlins Calidris alpina wintering at a similar latitude to facilitate a more direct intraspecific comparison. Our interspecific analyses showed that BMR was significantly lower in inland shorebirds than in coastal shorebirds after the effects of potentially confounding climatic (latitude, temperature, solar radiation, wind conditions) and organismal (body mass, migratory status, phylogeny) factors were accounted for. This indicates that part of the variation in basal metabolism might be attributed to genotypic divergence. Intraspecific comparisons showed that the mass-specific BMR of dunlins wintering in inland freshwater habitats was 15% lower than in coastal saline habitats, suggesting that phenotypic plasticity also plays an important role in generating these metabolic differences. We propose that the absence of tidally-induced food restrictions, low salinity, and less windy microclimates associated with inland freshwater habitats may reduce the levels of energy expenditure, and hence BMR. Further research including common-garden experiments that eliminate phenotypic plasticity

Environmental and ecological conditions at Arctic breeding sites have limited effects on true survival rates of adult shorebirds

Science.gov (United States)

Weiser, Emily L.; Lanctot, Richard B.; Brown, Stephen C.; Gates, H. River; Bentzen, Rebecca L.; Bêty, Joël; Boldenow, Megan L.; English, Willow B.; Franks, Samantha E.; Koloski, Laura; Kwon, Eunbi; Lamarre, Jean-Francois; Lank, David B.; Liebezeit, Joseph R.; McKinnon, Laura; Nol, Erica; Rausch, Jennie; Saalfeld, Sarah T.; Senner, Nathan R.; Ward, David H.; Woodard, Paul F.; Sandercock, Brett K.

2018-01-01

Many Arctic shorebird populations are declining, and quantifying adult survival and the effects of anthropogenic factors is a crucial step toward a better understanding of population dynamics. We used a recently developed, spatially explicit Cormack–Jolly–Seber model in a Bayesian framework to obtain broad-scale estimates of true annual survival rates for 6 species of shorebirds at 9 breeding sites across the North American Arctic in 2010–2014. We tested for effects of environmental and ecological variables, study site, nest fate, and sex on annual survival rates of each species in the spatially explicit framework, which allowed us to distinguish between effects of variables on site fidelity versus true survival. Our spatially explicit analysis produced estimates of true survival rates that were substantially higher than previously published estimates of apparent survival for most species, ranging from S = 0.72 to 0.98 across 5 species. However, survival was lower for the arcticolasubspecies of Dunlin (Calidris alpina arcticola; S = 0.54), our only study taxon that migrates through the East Asian–Australasian Flyway. Like other species that use that flyway, arcticola Dunlin could be experiencing unsustainably low survival rates as a result of loss of migratory stopover habitat. Survival rates of our study species were not affected by timing of snowmelt or summer temperature, and only 2 species showed minor variation among study sites. Furthermore, although previous reproductive success, predator abundance, and the availability of alternative prey each affected survival of one species, no factors broadly affected survival across species. Overall, our findings of few effects of environmental or ecological variables suggest that annual survival rates of adult shorebirds are generally robust to conditions at Arctic breeding sites. Instead, conditions at migratory stopovers or overwintering sites might be driving adult survival rates and should be the

Off-road sampling reveals a different grassland bird community than roadside sampling: implications for survey design and estimates to guide conservation

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Troy I. Wellicome

2014-06-01

Full Text Available Grassland bird species continue to decline steeply across North America. Road-based surveys such as the North American Breeding Bird Survey (BBS are often used to estimate trends and population sizes and to build species distribution models for grassland birds, although roadside survey counts may introduce bias in estimates because of differences in habitats along roadsides and in off-road surveys. We tested for differences in land cover composition and in the avian community on 21 roadside-based survey routes and in an equal number of adjacent off-road walking routes in the grasslands of southern Alberta, Canada. Off-road routes (n = 225 point counts had more native grassland and short shrubs and less fallow land and road area than the roadside routes (n = 225 point counts. Consequently, 17 of the 39 bird species differed between the two route types in frequency of occurrence and relative abundance, measured using an indicator species analysis. Six species, including five obligate grassland species, were more prevalent at off-road sites; they included four species listed under the Canadian federal Species At Risk Act or listed by the Committee on the Status of Endangered Wildlife in Canada: Sprague's Pipit (Anthus spragueii, Baird's Sparrow (Ammodramus bairdii, the Chestnut-collared Longspur (Calcarius ornatus, and McCown's Longspur (Rhynchophanes mccownii. The six species were as much as four times more abundant on off-road sites. Species more prevalent along roadside routes included common species and those typical of farmland and other human-modified habitats, e.g., the European Starling (Sturnus vulgaris, the Black-billed Magpie (Pica hudsonia, and the House Sparrow (Passer domesticus. Differences in avian community composition between roadside and off-road surveys suggest that the use of BBS data when generating population estimates or distribution models may overestimate certain common species and underestimate others of conservation

Lake Ontario benthic prey fish assessment, 2015

Science.gov (United States)

Weidel, Brian C.; Walsh, Maureen; Holden, Jeremy P.; Connerton, Michael J.

2016-01-01

Benthic prey fishes are a critical component of the Lake Ontario food web, serving as energy vectors from benthic invertebrates to native and introduced piscivores. Since the late 1970’s, Lake Ontario benthic prey fish status was primarily assessed using bottom trawl observations confined to the lake’s south shore, in waters from 8 – 150 m (26 – 492 ft). In 2015, the Benthic Prey Fish Survey was cooperatively adjusted and expanded to address resource management information needs including lake-wide benthic prey fish population dynamics. Effort increased from 55 bottom trawl sites to 135 trawl sites collected in depths from 8 - 225m (26 – 738 ft). The spatial coverage of sampling was also expanded and occurred in all major lake basins. The resulting distribution of tow depths more closely matched the available lake depth distribution. The additional effort illustrated how previous surveys were underestimating lake-wide Deepwater Sculpin, Myoxocephalus thompsonii, abundance by not sampling in areas of highest density. We also found species richness was greater in the new sampling sites relative to the historic sites with 11 new fish species caught in the new sites including juvenile Round Whitefish, Prosopium cylindraceum, and Mottled sculpin, Cottus bairdii. Species-specific assessments found Slimy Sculpin, Cottus cognatus abundance increased slightly in 2015 relative to 2014, while Deepwater Sculpin and Round Goby, Neogobius melanostomus, dramatically increased in 2015, relative to 2014. The cooperative, lake-wide Benthic Prey Fish Survey expanded our understanding of benthic fish population dynamics and habitat use in Lake Ontario. This survey’s data and interpretations influence international resource management decision making, such as informing the Deepwater Sculpin conservation status and assessing the balance between sport fish consumption and prey fish populations. Additionally a significant Lake Ontario event occurred in May 2015 when a single

Vulnerability of birds to climate change in California's Sierra Nevada

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Rodney B. Siegel

2014-06-01

Full Text Available In a rapidly changing climate, effective bird conservation requires not only reliable information about the current vulnerability of species of conservation concern, but also credible projections of their future vulnerability. Such projections may enable managers to preempt or reduce emerging climate-related threats through appropriate habitat management. We used NatureServe's Climate Change Vulnerability Index (CCVI to predict vulnerability to climate change of 168 bird species that breed in the Sierra Nevada mountains of California, USA. The CCVI assesses species-specific exposure and sensitivity to climate change within a defined geographic area, through the integration of (a species' range maps, (b information about species' natural history traits and ecological relationships, (c historic and current climate data, and (d spatially explicit climate change projections. We conducted the assessment under two different downscaled climate models with divergent projections about future precipitation through the middle of the 21st century. Assessments differed relatively little under the two climate models. Of five CCVI vulnerability ranking categories, only one species, White-tailed Ptarmigan (Lagopus leucura, received the most vulnerable rank, Extremely Vulnerable. No species received the second-highest vulnerability ranking, Highly Vulnerable. Sixteen species scored as Moderately Vulnerable using one or both climate models: Common Merganser (Mergus merganser, Osprey (Pandion haliaetus, Bald Eagle (Haliaeetus leucocephalus, Northern Goshawk (Accipiter gentilis, Peregrine Falcon (Falco peregrinus, Prairie Falcon (Falco mexicanus, Spotted Sandpiper (Actitis macularius, Great Gray Owl (Strix nebulosa, Black Swift (Cypseloides niger, Clark's Nutcracker (Nucifraga columbiana, American Dipper (Cinclus mexicanus, Swainson's Thrush (Catharus ustulatus, American Pipit (Anthus rubescens, Gray-crowned Rosy-Finch (Leucosticte tephrocotis, Pine Grosbeak

Dependence of waterbirds and shorebirds on shallow-water habitats in the Mid-Atlantic coastal region: An ecological profile and management recommendations

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Erwin, R.M.

1996-01-01

Waterbirds (waterfowl, colonially nesting wading and seabirds, ospreys [Pandion haliaetus], and bald eagles [Haliaeetus leucocephalus]) and shorebirds (sandpipers, plovers, and relatives) may constitute a large fraction of the top level carnivore trophic component in many shallow-water areas of the mid-Atlantic region. The large biomass of many species (>1 kg body mass for the two raptors and some waterfowl) and enormous populations (e.g., >1 million shorebirds in late May in parts of Delaware Bay) reveal the importance of waterbirds as consumers and as linkages in nutrient flux in many shallow-water habitats. Salt and brackish marsh shallow-water habitats, including marsh pannes and tidal pools and creeks as well as constructed impoundments, are used intensively during most months of the year; in fall and winter, mostly by dabbling ducks, in spring and summer by migrant shorebirds and breeding colonial wading birds and seabirds. In adjacent estuaries, the intertidal flats and littoral zones of shallow embayments are heavily used by shorebirds, raptors, and colonial waterbirds in the May to September periods, with use by duck and geese heaviest from October to March. With the regional degradation of estuarine habitats and population declines of many species of waterbirds in the past 20 yr, some management recommendations relevant to shallow waters include: better protection, enhancement, and creation of small bay islands (small and isolated to preclude most mammalian predators) for nesting and brooding birds, especially colonial species; establishment of sanctuaries from human disturbance (e.g., boating, hunting) both in open water (waterfowl) and on land, better allocation of sandy dredged materials to augment islands or stabilize eroding islands; improvement in water management of existing impoundments to ensure good feeding, resting, and nesting opportunities for all the waterbirds, support for policies to preclude point and nonpoint source runoff of chemicals

ADAPTIVE CHARACTERISTICS OF HERONS PLUMAGE FOR THEIR WAY OF LIFE

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Koshelev V. A.

2011-12-01

Full Text Available Feather cover of each bird species reflects spectra of species, age, sex and environmental attributes defined the phylogeny of taxa, habitat and life patterns. In turn, many ecological phenomena in the birds’ life patterns are directly dependent on the state of plumage (e.g., time of breeding, seasonal migration, roost flights. For the first time the quantitative characterization of six heron species' plumage were done as well as the description of powder down feathers. The adaptive features of feathers and various types of heron’s plumages were discussed.The structure of contour feathers of herons is related to the peculiarities of species life pattern. All the species have a relatively small number of contour feathers, despite their large body size. According to this index the herons are more similar to typical wading birds (gulls, sandpipers than for waterfowl. The total number of heron feathers slightly increase in winter, because they are migratory species. Structure of contour feathers of herons corresponds to that of other waterbirds. The rod is not bent, the feathers are large, and the mounting angle to the surface of the body is little. The cores of abdominal feather fracts reduce heat transfer and can be regarded as an adaptation factor to aquatic environment.Buoyancy is provided by heron’s feathers insignificantly, in contrast to the typical waterfowl species. Significant subcutaneous fat stores are typical for herons in spring, autumn and winter, increased buoyancy and being the energy reserves provide thermoregulation in cold environment. Our data indicate weak adaptation of herons’ plumage to aquatic environments, but also confirm its insulating properties, which is prove the herons semi-aquatic rather than aquatic life patterns.Due to color of plumage some three groups of herons were considered: white, mottled and camouflaged. Coloration of second and third group performs a protective function. We didn’t found a clear

H5N1 surveillance in migratory birds in Java, Indonesia.

Science.gov (United States)

Stoops, Arthur C; Barbara, Katie A; Indrawan, Mochamad; Ibrahim, Ima N; Petrus, Wicaksana B; Wijaya, Susan; Farzeli, Arik; Antonjaya, Ungke; Sin, Lim W; Hidayatullah, N; Kristanto, Ige; Tampubolon, A M; Purnama, S; Supriatna, Adam; Burgess, Timothy H; Williams, Maya; Putnam, Shannon D; Tobias, Steve; Blair, Patrick J

2009-12-01

We sought to elucidate the role of migratory birds in transmission of H5N1 in an enzoonotic area. Resident, captive, and migratory birds were sampled at five sites in Java, Indonesia. Mist nets were used to trap birds. Birds were identified to species. RNA was extracted from swabs and reverse transcriptase polymerase chain reaction (RT-PCR) conducted for the HA and M genes of H5N1. Antibodies were detected by enzyme-linked immunosorbent assay and hemagglutination inhibition test. Between October 2006 and September 2007, a total of 4,067 captive, resident, and migratory birds comprising 98 species in 23 genera were sampled. The most commonly collected birds were the common sandpiper (6% of total), striated heron (3%), and the domestic chicken (14%). The overall prevalence of H5N1 antibodies was 5.3%. A significantly higher percentage of captive birds (16.1%) showed antibody evidence of H5N1 exposure when compared to migratory or resident birds. The greatest number of seropositive birds in each category were Muschovy duck (captive), striated heron (resident), and the Pacific golden plover (migratory). Seven apparently well captive birds yielded molecular evidence of H5N1 infection. Following amplification, the HA, NA, and M genes were analyzed. Phylogenetic analysis of the HA gene showed that the isolates were 97% similar to EU124153.1 A/chicken/West Java/Garut May 2006, an isolate obtained in a similar region of West Java. While no known markers of neuraminidase inhibitor resistance were found within the NA gene, M segment analysis revealed the V27A mutation known to confer resistance to adamantanes. Our results demonstrate moderate serologic evidence of H5N1 infection in captive birds, sampled in five sites in Java, Indonesia, but only occasional infection in resident and migratory birds. These data imply that in an enzoonotic region of Indonesia the role of migratory birds in transmission of H5N1 is limited.

Rezultati januarskega štetja vodnih ptic leta 2015 v Sloveniji/ Results of the January 2015 waterbird census in Slovenia

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Božič Luka

2015-11-01

Full Text Available In 2015, the International Waterbird Census (IWC was carried out in Slovenia on 17 and 18 Jan. Waterbirds were counted on all larger rivers, along the entire Slovenian Coastland and on most of the major standing waters in the country. During the census, in which 276 observers took part, 409 sections of the rivers and coastal sea with a total length of 1385.8 km and 224 other localities (172 standing waters and 52 streams were surveyed. Altogether, 46,425 waterbirds of 57 species were counted. This is one of the lowest numbers of waterbirds recorded during the 19 years of IWC in Slovenia. The highest numbers of waterbirds were counted in the Drava count area, i.e. 17,014 individuals (36.7% of all waterbirds in Slovenia. By far the most numerous species was Mallard Anas platyrhynchos (45.9% of all waterbirds, followed by Coot Fulica atra (8.4% of all waterbirds, Blackheaded Gull Chroicocephalus ridibundus (7.5% of all waterbirds, Cormorant Phalacrocorax carbo (5.7% of all waterbirds and Mute Swan Cygnus olor (4.6% of all waterbirds. The number of 1000 counted individuals was also surpassed by Tufted Duck Aythya fuligula, Yellow-legged Gull Larus michahellis and Teal An. crecca. Among the rarer recorded species, the Cattle Egret Bubulcus ibis (registered only for the third time during the IWC and Lesser Black-backed Gull Larus fuscus (registered only for the fourth time during the IWC deserve special mention. Also, Ruddy Shelduck Tadorna ferruginea was recorded for the fourth time during the IWC, but the individual observed was classified to category E (introduced species without self-sustaining populations, escapees from captivity. Numbers of the following species were the highest so far recorded during the IWC: Greylag Goose Anser anser, Muscovy Duck Cairina moschata, Shoveler An. clypeata, Goosander Mergus merganser and Common Sandpiper Actitis hypoleucos. The number of Redbreasted Mergansers M. serrator was the lowest so far recorded during the

Rezultati januarskega štetja vodnih ptic leta 2014 v Sloveniji / Results of the January 2014 waterbird census in Slovenia

Directory of Open Access Journals (Sweden)

Božič Luka

2014-11-01

: Cormorant, Little Grebe Tachybaptus ruficollis and Green Sandpiper Tringa ochropus

Evaluating a multispecies adaptive management framework: Must uncertainty impede effective decision-making?

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Smith, David R.; McGowan, Conor P.; Daily, Jonathan P.; Nichols, James D.; Sweka, John A.; Lyons, James E.

2013-01-01

Application of adaptive management to complex natural resource systems requires careful evaluation to ensure that the process leads to improved decision-making. As part of that evaluation, adaptive policies can be compared with alternative nonadaptive management scenarios. Also, the value of reducing structural (ecological) uncertainty to achieving management objectives can be quantified.A multispecies adaptive management framework was recently adopted by the Atlantic States Marine Fisheries Commission for sustainable harvest of Delaware Bay horseshoe crabs Limulus polyphemus, while maintaining adequate stopover habitat for migrating red knots Calidris canutus rufa, the focal shorebird species. The predictive model set encompassed the structural uncertainty in the relationships between horseshoe crab spawning, red knot weight gain and red knot vital rates. Stochastic dynamic programming was used to generate a state-dependent strategy for harvest decisions given that uncertainty. In this paper, we employed a management strategy evaluation approach to evaluate the performance of this adaptive management framework. Active adaptive management was used by including model weights as state variables in the optimization and reducing structural uncertainty by model weight updating.We found that the value of information for reducing structural uncertainty is expected to be low, because the uncertainty does not appear to impede effective management. Harvest policy responded to abundance levels of both species regardless of uncertainty in the specific relationship that generated those abundances. Thus, the expected horseshoe crab harvest and red knot abundance were similar when the population generating model was uncertain or known, and harvest policy was robust to structural uncertainty as specified.Synthesis and applications. The combination of management strategy evaluation with state-dependent strategies from stochastic dynamic programming was an informative approach to

Modeling Bird Migration under Climate Change: A Mechanistic Approach

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Smith, James A.

2009-01-01

How will migrating birds respond to changes in the environment under climate change? What are the implications for migratory success under the various accelerated climate change scenarios as forecast by the Intergovernmental Panel on Climate Change? How will reductions or increased variability in the number or quality of wetland stop-over sites affect migratory bird species? The answers to these questions have important ramifications for conservation biology and wildlife management. Here, we describe the use of continental scale simulation modeling to explore how spatio-temporal changes along migratory flyways affect en-route migration success. We use an individually based, biophysical, mechanistic, bird migration model to simulate the movement of shorebirds in North America as a tool to study how such factors as drought and wetland loss may impact migratory success and modify migration patterns. Our model is driven by remote sensing and climate data and incorporates important landscape variables. The energy budget components of the model include resting, foraging, and flight, but presently predation is ignored. Results/Conclusions We illustrate our model by studying the spring migration of sandpipers through the Great Plains to their Arctic breeding grounds. Why many species of shorebirds have shown significant declines remains a puzzle. Shorebirds are sensitive to stop-over quality and spacing because of their need for frequent refueling stops and their opportunistic feeding patterns. We predict bird "hydrographs that is, stop-over frequency with latitude, that are in agreement with the literature. Mean stop-over durations predicted from our model for nominal cases also are consistent with the limited, but available data. For the shorebird species simulated, our model predicts that shorebirds exhibit significant plasticity and are able to shift their migration patterns in response to changing drought conditions. However, the question remains as to whether this

Brazil The Duck Lagoon

Science.gov (United States)

2002-01-01

(Ruppia maritima) which reaches peak production during summer. Sea turtles (Chelonia mydas) can be found in the lagoon during spring and summer. Although the lowland tapir (Tapirus terrestris) is found in some parts of Rio Grande do Sul, the Baird's tapir (Tapirus bairdii), is not distributed within the image area (it is restricted to Central America). MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center, Greenbelt, MD. JPL is a division of the California Institute of Technology. Image credit: NASA/GSFC/LaRC/JPL, MISR Team.

Concentrations of 17 elements, including mercury, in the tissues, food and abiotic environment of Arctic shorebirds

Energy Technology Data Exchange (ETDEWEB)

Hargreaves, Anna L., E-mail: alhargreaves@gmail.com [Calgary Zoo, Centre for Conservation Research, 1300 Zoo Rd NE, Calgary, AB, T2E 7V6 (Canada); Whiteside, Douglas P. [Calgary Zoo, Animal Health Centre, 1300 Zoo Rd NE, Calgary, AB, T2E 7V6 (Canada); University of Calgary, Department of Ecosystem and Public Health, Faculty of Veterinary Medicine, 2500 University Dr. NW, Calgary, AB, T2N 1N4 (Canada); Gilchrist, Grant [Carleton University, National Wildlife Research Centre, Ottawa, ON, KIA OH3 (Canada)

2011-09-01

Exposure to contaminants is one hypothesis proposed to explain the global decline in shorebirds, and is also an increasing concern in the Arctic. We assessed potential contaminants (As, Be, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Sb, Se, Tl, V, and Zn) at a shorebird breeding site in Nunavut, Canada. We compared element levels in soil, invertebrates and shorebird blood to assess evidence for bioconcentration and biomagnification within the Arctic-based food chain. We tested whether elements in blood, feathers and eggs of six shorebird species (Pluvialis squatarola, Calidris alpina, C. fuscicollis, Phalaropus fulicarius, Charadrius semipalmatus, and Arenaria interpres) were related to fitness endpoints: adult body condition, blood-parasite load, egg size, eggshell thickness, nest duration, and hatching success. To facilitate comparison to other sites, we summarise the published data on toxic metals in shorebird blood and egg contents. Element concentrations and invertebrate composition differed strongly among habitats, and habitat use and element concentrations differed among shorebird species. Hg, Se, Cd, Cu, and Zn bioconcentrated from soil to invertebrates, and Hg, Se and Fe biomagnified from invertebrates to shorebird blood. As, Ni, Pb, Co and Mn showed significant biodilution from soil to invertebrates to shorebirds. Soil element levels were within Canadian guidelines, and invertebrate Hg levels were below dietary levels suggested for the protection of wildlife. However, maximum Hg in blood and eggs approached levels associated with toxicological effects and Hg-pollution in other bird species. Parental blood-Hg was negatively related to egg volume, although the relationship varied among species. No other elements approached established toxicological thresholds. In conclusion, whereas we found little evidence that exposure to elements at this site is leading to the declines of the species studied, Hg, as found elsewhere in the Canadian Arctic, is of potential

Concentrations of 17 elements, including mercury, in the tissues, food and abiotic environment of Arctic shorebirds

International Nuclear Information System (INIS)

Hargreaves, Anna L.; Whiteside, Douglas P.; Gilchrist, Grant

2011-01-01

Exposure to contaminants is one hypothesis proposed to explain the global decline in shorebirds, and is also an increasing concern in the Arctic. We assessed potential contaminants (As, Be, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Sb, Se, Tl, V, and Zn) at a shorebird breeding site in Nunavut, Canada. We compared element levels in soil, invertebrates and shorebird blood to assess evidence for bioconcentration and biomagnification within the Arctic-based food chain. We tested whether elements in blood, feathers and eggs of six shorebird species (Pluvialis squatarola, Calidris alpina, C. fuscicollis, Phalaropus fulicarius, Charadrius semipalmatus, and Arenaria interpres) were related to fitness endpoints: adult body condition, blood-parasite load, egg size, eggshell thickness, nest duration, and hatching success. To facilitate comparison to other sites, we summarise the published data on toxic metals in shorebird blood and egg contents. Element concentrations and invertebrate composition differed strongly among habitats, and habitat use and element concentrations differed among shorebird species. Hg, Se, Cd, Cu, and Zn bioconcentrated from soil to invertebrates, and Hg, Se and Fe biomagnified from invertebrates to shorebird blood. As, Ni, Pb, Co and Mn showed significant biodilution from soil to invertebrates to shorebirds. Soil element levels were within Canadian guidelines, and invertebrate Hg levels were below dietary levels suggested for the protection of wildlife. However, maximum Hg in blood and eggs approached levels associated with toxicological effects and Hg-pollution in other bird species. Parental blood-Hg was negatively related to egg volume, although the relationship varied among species. No other elements approached established toxicological thresholds. In conclusion, whereas we found little evidence that exposure to elements at this site is leading to the declines of the species studied, Hg, as found elsewhere in the Canadian Arctic, is of potential

Rapid diagnosis of avian influenza virus in wild birds: Use of a portable rRT-PCR and freeze-dried reagents in the field

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Takekawa, John Y.; Hill, N.J.; Schultz, A.K.; Iverson, S.A.; Cardona, C.J.; Boyce, W.M.; Dudley, J.P.

2011-01-01

Wild birds have been implicated in the spread of highly pathogenic avian influenza (HPAI) of the H5N1 subtype, prompting surveillance along migratory flyways. Sampling of wild birds for avian influenza virus (AIV) is often conducted in remote regions, but results are often delayed because of the need to transport samples to a laboratory equipped for molecular testing. Real-time reverse transcriptase polymerase chain reaction (rRT-PCR) is a molecular technique that offers one of the most accurate and sensitive methods for diagnosis of AIV. The previously strict lab protocols needed for rRT-PCR are now being adapted for the field. Development of freeze-dried (lyophilized) reagents that do not require cold chain, with sensitivity at the level of wet reagents has brought on-site remote testing to a practical goal. Here we present a method for the rapid diagnosis of AIV in wild birds using an rRT-PCR unit (Ruggedized Advanced Pathogen Identification Device or RAPID, Idaho Technologies, Salt Lake City, UT) that employs lyophilized reagents (Influenza A Target 1 Taqman; ASAY-ASY-0109, Idaho Technologies). The reagents contain all of the necessary components for testing at appropriate concentrations in a single tube: primers, probes, enzymes, buffers and internal positive controls, eliminating errors associated with improper storage or handling of wet reagents. The portable unit performs a screen for Influenza A by targeting the matrix gene and yields results in 2-3 hours. Genetic subtyping is also possible with H5 and H7 primer sets that target the hemagglutinin gene. The system is suitable for use on cloacal and oropharyngeal samples collected from wild birds, as demonstrated here on the migratory shorebird species, the western sandpiper (Calidrus mauri) captured in Northern California. Animal handling followed protocols approved by the Animal Care and Use Committee of the U.S. Geological Survey Western Ecological Research Center and permits of the U.S. Geological Survey

Molluscs of an intertidal soft-sediment area in China: Does overfishing explain a high density but low diversity community that benefits staging shorebirds?

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Yang, Hong-Yan; Chen, Bing; Piersma, Theunis; Zhang, Zhengwang; Ding, Changqing

2016-03-01

The Yellow Sea is a key staging ground for shorebirds that migrate from Australasia to the Arctic each spring. A lot of attention has been paid to the impact of habitat loss due to land reclamation on shorebird survival, but any effects of overfishing of coastal resources are unclear. In this study, the abundance of molluscs in the intertidal mudflats of northern Bohai Bay on the Chinese Yellow Sea was investigated in 2008-2014 from the perspective of their importance as food for northward migrating shorebirds, especially Red Knots Calidris canutus. Numerically contributing 96% to the numbers of 17 species found in spring 2008, the bivalve Potamocorbula laevis (the staple food of Red Knots and other shorebirds) dominated the intertidal mollusc community. In the spring of 2008-2014, the densities of P. laevis were surprisingly high, varying between 3900 and 41,000 individuals/m2 at distinctly small sizes (average shell lengths of 1.1 to 4.8 mm), and thus reaching some of the highest densities of marine bivalves recorded worldwide and providing good food for shorebirds. The distribution of P. laevis was associated with relatively soft sediments in close proximity to the recently built seawalls. A monthly sampling programme showed steep seasonal changes in abundance and size. P. laevis were nearly absent in winter, each year settling on the intertidal mudflats anew. Peak densities were reached in spring, when 0-age P. laevis were 1-3 mm long. The findings point to a highly unusual demographic structure of the species, suggesting that some interfering factors are at play. We hypothesise that the current dominance of young P. laevis in Bohai Bay reflects the combined pressures of a nearly complete active removal of adult populations from mid-summer to autumn for shrimp farming (this clearing of adults may offer space for recruitment during the next spring) and low numbers of epibenthic predators of bivalves, such as shrimps and crabs, due to persistent overfishing in

Economic design in a long-distance migrating molluscivore: how fast-fuelling red knots in Bohai Bay, China, get away with small gizzards.

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Yang, Hong-Yan; Chen, Bing; Ma, Zhi-Jun; Hua, Ning; van Gils, Jan A; Zhang, Zheng-Wang; Piersma, Theunis

2013-10-01

We carried out an observational and experimental study to decipher how resource characteristics, in interaction with the predator's phenotype, constrain a fitness-determining performance measure, i.e. refuelling in a migrant bird. Two subspecies of red knot (Calidris canutus rogersi and C. c. piersmai) use northern Bohai Bay, Yellow Sea, China, for the final prebreeding stopover, during their 10,000-15,000 km long migrations between wintering and breeding areas. Here, they feed on small bivalves, especially 2-7 mm long Potamocorbula laevis. With an average stay of 29 days, and the need to store 80 g of fat for the onward flights to high-Arctic breeding grounds, red knots need to refuel fast. Using existing knowledge, we expected them to achieve this on the basis of (1) prey with high flesh to shell mass ratios, (2) large gizzards to crush the ingested molluscs, or (3) a combination of the two. Rejecting all three predictions, we found that red knots staging in Bohai Bay had the smallest gizzards on record (4.9 ± 0.8 g, mean ± s.e.m., N = 27), and also found that prey quality of P. laevis is much lower than predicted for the measured gizzard size (i.e. 1.3 rather than the predicted 4.5 kJ g(-1) dry shell mass, DM(shell)). The estimated handling time of P. laevis (0.2 s) is much shorter than the observed time between two prey ingestions (0.7 s), indicating that prey handling time is no constraint. Based on field observations of dropping rates and on indoor digestion trails, the shell processing rate was estimated at 3.9 mg DM(shell) s(-1), i.e. three times higher the rate previously predicted for red knots eating as fast as they can with the measured gizzard size. This is explained by the small and easily crushed P. laevis enabling high processing rates. As P. laevis also occurred in high densities, the metabolizable energy intake rate of red knots with small gizzards at 5 J s(-1) was as high as at northward staging sites elsewhere in the world. Currently

Bird Migration Under Climate Change - A Mechanistic Approach Using Remote Sensing

Science.gov (United States)

Smith, James A.; Blattner, Tim; Messmer, Peter

2010-01-01

migratory shorebirds in the central fly ways of North America. We demonstrated the phenotypic plasticity of a migratory population of Pectoral sandpipers consisting of an ensemble of 10,000 individual birds in response to changes in stopover locations using an individual based migration model driven by remotely sensed land surface data, climate data and biological field data. With the advent of new computing capabilities enabled hy recent GPU-GP computing paradigms and commodity hardware, it now is possible to simulate both larger ensemble populations and to incorporate more realistic mechanistic factors into migration models. Here, we take our first steps use these tools to study the impact of long-term drought variability on shorebird survival.

Post-breeding migration and connectivity of red knots in the Western Atlantic

Science.gov (United States)

Lyons, James E.; Winn, Bradford; Keyes, Timothy; Kalasz, Kevin S.

2018-01-01

Red knots (Calidris canutus rufa) have 3 distinct nonbreeding regions: 1 in the southeastern United States and Caribbean, another on the northeast coast of Brazil in the Maranhão region, and a third along the Patagonian coasts of Chile and Argentina. Effective conservation and recovery of this threatened long-distance migrant will require knowledge of population structure, migration ecology, and abundance and distribution throughout the annual cycle. We conducted a stopover population and biogeographic assessment of knots at the Altamaha River Delta, Georgia, an important stopover area in the southeastern United States. We estimated stopover population size and stopover duration during post-breeding migration in 2011 at the Altamaha study area using mark-resight data, and we inferred nonbreeding regions for this stopover population using stable isotope ratios of carbon and nitrogen in feathers, and observations (sightings and captures) during boreal winter from across the hemisphere. With an integrated Bayesian analysis of all these data, we also estimated the number of birds in the southeastern United States and northern Brazil during boreal winter. For mark-resight analyses in Georgia, we made observations of marked individuals during 14 weeks from early August to early November 2011 and detected 814 individually marked birds. We used the Jolly-Seber mark-recapture model and estimated the southbound passage population at approximately 23,400 red knots. In ongoing studies elsewhere, isotope samples were collected from 175 (21%) of the 814 birds detected in our study, and ≥1 sighting or capture record during boreal winter was located in data repositories for 659 birds (81%). Isotopic signatures and boreal winter records indicate that the majority (82–96%) of the birds that stopped at the Altamaha Delta spend the boreal winter in the northern part of the nonbreeding range (southeast USA, Caribbean, and northern Brazil). Knots migrating to the southeastern

How the food supply harvestable by waders in the Wadden Sea depends on the variation in energy density, body weight, biomass, burying depth and behaviour of tidal-flat invertebrates

Science.gov (United States)

Zwarts, Leo; Wanink, Jan H.

For several reasons, waders in the Wadden Sea face a large seasonal and annual variation in their food supply. Observations on a tidal flat in the Dutch Wadden Sea have shown that: - (1) The average energy density of ten invertebrate prey species varies between 21 and 23 kJ·g -1 AFDW. In Scrobicularia plana and Mya arenaria, but not in Macoma balthica, the energy density is 10% lower in winter than in summer. - (2) Depending on the species, body weights of prey of similar size are 30 to 60% lower in winter than in summer. - (3) The year-to-year fluctuation in standing-crop biomass is larger in some species than in others, the difference depending mainly on the frequency of successful recruitment. The overall biomass of the macrobenthos in winter is half of that in summer, but the timing of the peak biomass differs per species. - (4) The burying depth varies per species: Cerastoderma edule live just beneath the surface, while M. balthica, S. plana, M. arenaria, Arenicola marina and Nereis diversicolor bury more deeply and the majority of these prey live out of reach of the bird's bill. In all six species, burying depth increases with size. There is no seasonal variation in depth of C. edule and M. arenaria, but the four other species live at most shallow depth in early summer and most deeply in midwinter. Burying depths in winter vary from year to year, but are unrelated to temperature. Neither has temperature any effect on depth within months. For knot Calidris canutus feeding on M. balthica, the fluctuation in the accessible fraction was the main source of variation in the biomass of prey that is actually harvestable, i.e. the biomass of prey of suitable size that is accessible. Accordingly, the paper reviews the available data on the temporal variations in accessibility, detectability, ingestibility, digestibility and profitability of prey for waders. Only a small part of the prey is harvestable since many accessible prey are ignored because of their low

Selenium in ecosystems within the mountaintop coal mining and valley-fill region of southern West Virginia-assessment and ecosystem-scale modeling

Science.gov (United States)

Presser, Theresa S.

2013-01-01

Coal and associated waste rock are among environmental selenium (Se) sources that have the potential to affect reproduction in fish and aquatic birds. Ecosystems of southern West Virginia that are affected by drainage from mountaintop coal mines and valleys filled with waste rock in the Coal, Gauley, and Lower Guyandotte watersheds were assessed during 2010 and 2011. Sampling data from earlier studies in these watersheds (for example, Upper Mud River Reservoir) and other mining-affected watersheds also are included to assess additional hydrologic settings and food webs for comparison. Basin schematics give a comprehensive view of sampled species and Se concentration data specific to location and date. Food-web diagrams document the progression of Se trophic transfer across suspended particulate material, invertebrates, and fish for each site to serve as the basis for developing an ecosystem-scale model to predict Se exposure within the hydrologic conditions and food webs of southern West Virginia. This approach integrates a site-specific predator’s dietary exposure pathway into modeling to ensure an adequate link to Se toxicity and, thus, to species vulnerability. Site-specific fish abundance and richness data in streams documented various species of chub, shiner, dace, darters, bass, minnow, sunfish, sucker, catfish, and central stoneroller (Campostoma anomalum), mottled sculpin (Cottus bairdii), and least brook lamprey (Lampetra aepyptera). However, Se assessment species for streams, and hence, model species for streams, were limited to creek chub (Semotilus atromaculatus) and central stoneroller. Both of these species of fish are generally considered to have a high tolerance for environmental stress based on traditional comparative fish community assessment, with creek chub being present at all sites. Aquatic insects (mayfly, caddisfly, stonefly, dobsonfly, chironomid) were the main invertebrates sampled in streams. Collection of suspended particulate material