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Sample records for black-crowned night-heron nycticorax

  1. Swimming black-crowned night-herons (Nycticorax nycticorax) Kleptoparasitize American coots (Fulica americana)

    DEFF Research Database (Denmark)

    Graves, Gary R.

    2015-01-01

    I observed black-crowned night-herons (Nycticorax nycticorax) swimming and kleptoparasitizing American coots (Fulica americana) at an artificial lake in Pinal County, Arizona. This appears to be the first record of interspecific kleptoparasitism by a swimming ardeid.......I observed black-crowned night-herons (Nycticorax nycticorax) swimming and kleptoparasitizing American coots (Fulica americana) at an artificial lake in Pinal County, Arizona. This appears to be the first record of interspecific kleptoparasitism by a swimming ardeid....

  2. Observations of indirect filial cannibalism in response to nest failure of Black-crowned Night-Herons (Nycticorax nycticorax)

    Science.gov (United States)

    Brussee, Brianne E.; Coates, Peter S.; Dwight, Ian; Young, Laura G.

    2017-01-01

    During 2011, four separate instances of indirect filial cannibalism, whereby adults consumed their young that died from unknown causes, were observed using video-monitoring techniques in a nesting colony of Black-crowned Night-Herons (Nycticorax nycticorax) on Alcatraz Island. Though they were not observed actively killing their young, in all four observations adult Black-crowned Night-Herons consumed their young following death (i.e., indirect filial cannibalism). We could not determine cause of chick mortality, but parental neglect was likely a contributing factor in at least two instances. Indirect filial cannibalism is not commonly documented among birds, and understanding how cannibalism contributes to nest failure can help researchers better understand factors that limit nesting populations.

  3. Lead accumulation in feathers of nestling black-crowned night-herons (Nycticorax nycticorax) experimentally treated in the field

    Science.gov (United States)

    Golden, N.H.; Rattner, B.A.; Cohen, J.B.; Hoffman, D.J.; Russek-Cohen, E.; Ottinger, M.A.

    2003-01-01

    Although lead can attain high concentrations in feathers, interpretation of the biological significance of this phenomenon is difficult. As part of an effort to develop and validate non-invasive methods to monitor contaminant exposure in free-ranging birds, lead uptake by feathers of nestling black-crowned night-herons (Nycticorax nycticorax) was evaluated in a controlled exposure study. Four to six day-old heron nestlings (one/nest) at Chincoteague Bay, Virginia, received a single intraperitoneal injection of dosing vehicle (control; n=7) or a dose of lead nitrate in water (0.01, 0.05, or 0.25 mg Pb/g body weight of nestling; n=6 or 7/dose) chosen to yield feather lead concentrations found at low to moderately polluted sites. Nestlings were euthanized at 15 days of age. Lead accumulation in feathers was associated with concentrations in bone, kidney, and liver (r = 0.32 - 0.74, p < 0.02), but exhibited only modest dose-dependence. Blood delta-aminolevulinic acid dehydratase activity was inhibited by lead, although effects on other biochemical endpoints were marginal. Tarsus growth rate was inversely related to feather lead concentration. Culmen growth rate was depressed in nestlings treated with the highest dose of lead, but not correlated with feather lead concentration. These findings provide evidence that feathers of nestling herons are a sensitive indicator of lead exposure and have potential application for the extrapolation of lead concentrations in other tissues and the estimation of environmental lead exposure in birds.

  4. Absorption and biotransformation of polybrominated diphenyl ethers DE-71 and DE-79 in chicken (Gallus gallus), mallard (Anas platyrhynchos), American kestrel (Falco sparverius) and black-crowned night-heron (Nycticorax nycticorax) eggs

    Science.gov (United States)

    McKernan, Moira A.; Rattner, Barnett A.; Hatfield, Jeff S.; Hale, Robert C.; Ottinger, Mary Ann

    2010-01-01

    We recently reported that air cell administration of penta-brominated diphenyl ether (penta-BDE; DE-71) evokes biochemical and immunologic effects in chicken (Gallus gallus) embryos at very low doses, and impairs pipping (i.e., stage immediately prior to hatching) and hatching success at 1.8 ug g-1 egg (actual dose absorbed) in American kestrels (Falco sparverius). I n the present study, absorption of polybrominated diphenyl ether (PBDE) congeners was measured following air cell administration of a penta-BDE mixture (11.1 ug DE-71 g-1 egg) or an octa-brominated diphenyl ether mixture (octa-BDE; DE-79; 15.4 ug DE-79 g-1 egg). Uptake of PBDE congeners was measured at 24 h post-injection, midway through incubation, and at pipping in chicken, mallard (Anas platyrhynchos), and American kestrel egg contents, and at the end of incubation in black-crowned night-heron (Nycticorax nycticorax) egg contents. Absorption of penta-BDE and octa-BDE from the air cell into egg contents occurred throughout incubation; at pipping, up to 29.6% of penta-BDE was absorbed, but only 1.40-6.48% of octa-BDE was absorbed. Higher brominated congeners appeared to be absorbed more slowly than lower brominated congeners, and uptake rate was inversely proportional to the log Kow of predominant BDE congeners. Six congeners or co-eluting pairs of congeners were detected in penta-BDE-treated eggs that were not found in the dosing solution suggesting debromination in the developing embryo, extraembryonic membranes, and possibly even in the air cell membrane. This study demonstrates the importance of determining the fraction of xenobiotic absorbed into the egg following air cell administration for estimation of the lowest-observed-effect level.

  5. Mercury and drought along the lower Carson River, Nevada: II. Snowy egret and black-crowned night-heron reproduction on Lahontan Reservoir, 1997-2006

    Science.gov (United States)

    Hill, E.F.; Henny, C.J.; Grove, R.A.

    2008-01-01

    Mercury concentrations in the floodplain of the Carson River Basin in northwestern Nevada are some of the highest ever reported in a natural system. Thus, a portion of the basin including Lahontan Reservoir was placed on the U.S. Environmental Protection Agency's Natural Priorities List for research and cleanup. Preliminary studies indicated that reproduction in piscivorous birds may be at risk. Therefore, a 10-year study (1997-2006) was conducted to evaluate reproduction of snowy egrets (Egretta thula) and black-crowned night-herons (Nycticorax nycticorax) nesting on Gull Island in Lahontan Reservoir. Special attention was given to the annual flow of the Carson River, the resultant fluctuation of this irrigation reservoir, and the annual exposure of snowy egrets and night-herons to methylmercury (MeHg). The dynamic character of the river due to flooding and drought (drought effect) influenced snowy egret and night-heron reproduction more so than did MeHg contamination of eggs. During an extended drought (2000-2004) in the middle of the study, snowy egret nests containing eggs with concentrations of MeHg (measured as total mercury [THg] ??? 100% MeHg) ???0.80 ??g THg/g, ww, all failed, but in 1997 and 2006 (wet years with general flooding), substantial numbers of young were produced (but fewer than at nests where eggs contained Science+Business Media, LLC.

  6. Mercury and drought along the lower Carson River, Nevada: I. Snowy egret and black-crowned night-heron annual exposure to mercury, 1997-2006

    Science.gov (United States)

    Henny, C.J.; Hill, E.F.; Grove, R.A.; Kaiser, J.L.

    2007-01-01

    The dynamic nature of the annual volume of water discharged down the Carson River over a 10-year period, which included a century flood and drought, was examined in order to gain a better understanding of mercury movement, biological availability, and exposure to waterbirds nesting at Lahontan Reservoir. Total annual water discharge directly influenced total mercury (THg) in unfiltered water above the reservoir and downstream of a mining area, whereas methyl mercury (MeHg) at the same site was negatively related to annual discharge. Annual water storage at Lahontan Reservoir in the spring and early summer, as expected, was directly related to annual Carson River discharge. In contrast to the findings from above the reservoir, annual MeHg concentrations in water sampled below the reservoir were positively correlated with the total discharge and the amount of water stored in the reservoir on 1 July; that is, the reservoir is an important location for mercury methylation, which agrees with earlier findings. However, unfiltered water MeHg concentrations were about 10-fold higher above than below the reservoir, which indicated that much MeHg that entered as well as that produced in the reservoir settled out in the reservoir. Avian exposure to mercury at Lahontan Reservoir was evaluated in both eggs and blood of young snowy egrets (Egretta thula) and black-crowned night-herons (Nycticorax nycticorax). Annual MeHg concentrations in unfiltered water below the reservoir, during the time period (Julian Days 90-190) when birds were present, correlated significantly with mercury concentrations in night-heron blood (r 2= 0.461, p = 0.027), snowy egret blood (r 2= 0.474, p = 0.024), and night-heron eggs (r 2 = 0.447, p = 0.029), but not snowy egret eggs. A possible reason for lack of an MeHg water correlation with snowy egret eggs is discussed and relates to potential exposure differences associated with the food habits of both species. THg concentrations in water collected

  7. Mercury and drought along the Lower Carson River, Nevada: III. effects on blood and organ biochemistry and histopathology of snowy egrets and black-crowned night-herons on Lahontan Reservoir, 2002-2006

    Science.gov (United States)

    Hoffman, David J.; Henny, Charles J.; Hill, Elwood F.; Grove, Robert A.; Kaiser, James L.; Stebbins, Katherine R.

    2009-01-01

    A 10-year study (1997-2006) was conducted to evaluate reproduction and health of aquatic birds in the Carson River Basin of northwestern Nevada (on the U.S. Environmental Protection Agency Natural Priorities List) due to high mercury (Hg) concentrations from past mining activities. This part of the study evaluated physiological associations with blood Hg in young snowy egrets (Egretta thula) and black-crowned night-herons (Nycticorax nycticorax), and organ biochemistry and histopathological effects in snowy egrets on Lahontan Reservoir (LR) from the period 2002-2006. LR snowy egret geometric mean total Hg concentrations (μg/g ww) ranged from 1.5 to 4.8 for blood, 2.4 to 3.1 liver, 1.8 to 2.5 kidneys, 1.7 to 2.4 brain, and 20.5 to 36.4 feathers over these years. For night-herons, mean Hg for blood ranged from 1.6 to 7.4. Significant positive correlations were found between total Hg in blood and five plasma enzyme activities of snowy egrets suggesting hepatic stress. Histopathological findings revealed vacuolar changes in hepatocytes in LR snowy egrets as well as correlation of increased liver inflammation with increasing blood and tissue Hg. Hepatic oxidative effects were manifested by decreased hepatic total thiol concentration and glutathione reductase activity and elevated hepatic thiobarbituric acid-reactive substances (TBARS), a measure of lipid peroxidation. However, other hepatic changes indicated compensatory mechanisms in response to oxidative stress, including decreased oxidized glutathione (GSSG) concentration and decreased ratio of GSSG to reduced glutathione. In young black-crowned night-herons, fewer correlations were apparent. In both species, positive correlations between blood total Hg and plasma uric acid and inorganic phosphorus were suggestive of renal stress, which was supported by histopathological findings. Both oxidative effects and adaptive responses to oxidative stress were apparent in kidneys and brain. Vacuolar change and inflammation in

  8. Reprodução de Nycticorax nycticorax (Linnaeus no litoral de Santa Catarina, Brasil Reproduction of the Nycticorax nycticorax (Linnaeus in the Santa Catarina's coast, Brazil

    Directory of Open Access Journals (Sweden)

    Joaquim O. Branco

    2005-06-01

    Full Text Available O savacu Nycticorax nycticorax (Linnaeus, 1758 é uma espécie de hábitos crepusculares e noturnos, com ampla distribuição geográfica. Sua biologia reprodutiva tem sido intensivamente estudada nos países de ocorrência, entretanto, no Brasil, é comumente citada nos levantamentos de ornitólogos, mas não existem informações disponíveis sobre seu ciclo de vida. Esse trabalho objetiva contribuir para o conhecimento da biologia reprodutiva dessa espécie no litoral catarinense. As amostragens foram realizadas nos anos de 2000 a 2002 na Ilha dos Pássaros e de 2002 na Ilha dos Lobos, Santa Catarina. As maiores abundâncias de exemplares e ninhos com ovos ocorreram em outubro, sendo que o comprimento médio dos ovos variou entre 5,02 ± 0,23 a 5,07 ± 0,21 cm e o volume 31,71 ± 2,64 a 35,92 ± 3,47 cm³ e as maiores freqüências de filhotes em novembro, culminando o abandono da colônia em meados de janeiro. Foram identificados sete itens nos regurgitos dos filhotes, sendo que os peixes marinhos representaram 44,4% da massa total. O principal predador na colônia foi o urubu-comum, que atuou sobre os ovos no início da temporada e os filhotes no final.The black-crowned night heron N. nycticorax (Linnaeus, 1758 is a aquatic bird with twilight and night habits, with wide geographical distribution. His reproductive biology has been studied intensively at the occurrence countries, however, in Brazil, it is mentioned commonly in the ornithologists' risings, but available information don't exist on his life cycle. This work aims to contribute for the knowledge of the reproductive biology of that species in the Santa Catarina coast. The samplings were accomplished in the years from 2000 to 2002 in the Ilha dos Pássaros and of 2002 in the Ilha dos Lobos, Santa Catarina. The largest abundances of individuals and nests with eggs happened in October, and the medium length of the eggs varied between 5.02 ± 0.23 to 5.07 ± 0.21 cm and the volume 31

  9. Colonial nesting Yellow-crowned Night Herons on the San Antonio River Walk

    Science.gov (United States)

    Boal, Clint W.

    2010-01-01

    Yellow-crowned Night Herons (Nyctinassa violacea) typically nest as single pairs or in small colonies of about four pairs with high internest distances. They are also reported as susceptible to disturbance and to avoid habitat with high human use. However, some Yellowcrowned Night Herons habituate to human-dominated landscapes and nest in residential areas. I located a colony of nesting Yellow-crowned Night Herons in San Antonio, Texas on the River Walk, a popular tourist destination with an estimated 2.5 million visitors annually. I located 68 and 71 active nests in 2008 and 2009, respectively. This suggests the breeding population of the colony was 142 adult birds (77 adult herons/linear km of River Walk) in 2009. Herons occurred in a colony with three nesting aggregations situated 241 (±14 SD) m apart. Aggregations averaged 23.7 (±8.7 SD) nests each with one–nine nests per tree; nest trees within each aggregation were usually adjacent. Nests averaged 16.7 m (±4.1 SD) above ground, with 56% of nests over the river, 23% over sidewalks, 17% over dining areas, and 3% over landscaping. Only bald cypress (Taxodium distichum) was used for nest trees, and these were significantly taller and larger in diameter than random bald cypress trees. The herons were habituated to pedestrian activities, often perching only a few meters over sidewalks or dining areas, and foraging along the water’s edge as pedestrians passed within 4–5 m. Nests located over dining areas and sidewalks do impose some management issues. It is apparent the species is capable of habituating to human activities to exploit suitable urban settings for nesting and foraging habitat.

  10. The impact of capture, domestication and trade on Black Crowned ...

    African Journals Online (AJOL)

    The inland delta of the Niger, a vast floodplain, is the only refuge of Black Crowned Cranes in Mali. This study, centred on the regions of Mopti, Tenenkou and Youwarou, aimed to: (1) census the number of cranes in the delta and in captivity in the towns of Mopti and Bamako; (2) examine exploitation at different levels (local ...

  11. Selenium and metal concentrations in waterbird eggs and chicks at Agassiz National Wildlife Refuge, Minnesota

    Science.gov (United States)

    Custer, T.W.; Custer, Christine M.; Eichhorst, B.A.; Warburton, D.

    2007-01-01

    Exceptionally high cadmium (Cd) and chromium (Cr) concentrations were reported in eggs, feathers, or livers of selected waterbird species nesting at Agassiz National Wildlife Refuge (Agassiz) in 1994. Ten- to 15-day-old Franklin's gull (Larus pipixcan), black-crowned night-heron (Nycticorax nycticorax), and eared grebe (Podiceps nigricollis) chicks were collected in 1998, 1999, and 2001 at Agassiz and analyzed for selenium (Se) and metals including Cd and Cr. Freshly laid eggs were collected in 2001 from Franklin's gull, black-crowned night-heron, eared grebe, and pied-billed grebe (Podilymbus podiceps) nests at Agassiz. Based on a multivariate analysis, the pattern of Se and metal concentrations differed among species for eggs, chick feathers, and chick livers. Low Cd and Cr concentrations were measured in eggs, chick livers, and chick feathers of all four species. Mercury concentrations in black-crowned night-heron and eared grebe eggs collected from Agassiz in 2001 were lower than concentrations reported in 1994. Se and metal concentrations, including Cd and Cr, in waterbird eggs and chicks collected at Agassiz in 1998, 1999, and 2001 were not at toxic levels. ?? 2007 Springer Science+Business Media, LLC.

  12. Trace element residues in water, sediments, and organs of Savacu (Nycticorax nycticorax from Sepetiba Bay, Rio de Janeiro, Brazil

    Directory of Open Access Journals (Sweden)

    Marco Aurélio P. Horta

    2010-04-01

    Full Text Available Heavy metal (Cr, Cd, Zn, Cu, Ni, Pb concentrations in water, sediment and organs of Savacu, Nycticorax nycticorax were analyzed. Samples of water and sediment were collected from seven stations along Sepetiba Bay, and experimental animals, also were collected in the study area. This bay receives effluents discharges from heavily industrialized and highly populated settlements. Samples of water, sediment and Savacu were processed and analyzed for heavy metals and the results showed that these concentrations in sediment were higher than in water. The exposure to metals either in the water or by the effect of bioaccumulation in the food chain is reflected in the results obtained with animals’ test.

  13. Effects of contaminants on reproductive success of aquatic birds nesting at Edwards Air Force Base, California

    Science.gov (United States)

    Hothem, R.L.; Crayon, J.J.; Law, M.A.

    2006-01-01

    Contamination by organochlorine pesticides (OCs), polychlorinated biphenyls, metals, and trace elements at Edwards Air Force Base (EAFB), located in the Mojave Desert, could adversely affect nesting aquatic birds, especially at the sewage lagoons that comprise Piute Ponds. Estimates of avian reproduction, in conjunction with analyses of eggs and avian foods for contaminant residues, may indicate the potential for negative effects on avian populations. From 1996 to 1999, we conducted studies at the Piute Ponds area of EAFB to evaluate the impacts of contaminants on nesting birds. Avian reproduction was evaluated in 1999. Eggs were collected for chemical analyses in 1996 and 1999, and African clawed frogs (Xenopus laevis), a likely food source, were collected for chemical analyses in 1998. Avian species occupying the higher trophic levels-black-crowned night-heron (Nycticorax nycticorax), white-faced ibis (Plegadis chihi), and American avocet (Recurvirostra americana)-generally bioaccumulated higher concentrations of contaminants in their eggs. Reproductive success and egg hatchability of night-herons and white-faced ibises in the Piute Ponds were similar to results observed at other western colonies. Deformities were observed in only one embryo in this study, but concentrations of contaminants evaluated in this ibis embryo were considered insufficient to have caused the deformities. Because clawed frogs, a primary prey item for night-herons at Piute Ponds, had no detectable levels of any OCs, it is likely that OCs found in night-heron eggs were acquired from the wintering grounds rather than from EAFB. The presence of isomers of dichlorodiphenyltrichloroethane (DDT) in ibis eggs indicated recent exposure, but invertebrates used for food by ibises were not sampled at Piute Ponds, and conclusions about the source of OCs in ibis eggs could not be made. Concentrations of contaminants in random and failed eggs of individual species were not different, and we concluded

  14. Avian species differences in the intestinal absorption of xenobiotics (PCB, dieldrin, Hg2+)

    Science.gov (United States)

    Serafin, J.A.

    1984-01-01

    1. Intestinal absorption of a polychlorinated biphenyl, dieldrin, and mercury (from HgCl2) was measured in adult Northern bobwhites, Eastern screech owls, American kestrels, black-crowned night-herons and mallards in vivo by an in situ luminal perfusion technique.2. Bobwhites, screech owls and kestrels absorbed much more of each xenobiotic than black-crowned night-herons and mallards.3. Mallards absorbed less dieldrin and mercury than black-crowned night-herons.4. Mercury absorption by kestrels was more than twice that in screech owls and eight times that observed in mallards.5. Pronounced differences in xenobiotic absorption rates between bobwhites, screech owls and kestrels on the one hand, and black-crowned night-herons and mallards on the other, raise the possibility that absorptive ability may be associated with the phylogenetic classification of birds.

  15. Transboundary pollution: Persistent organochlorine pesticides in migrant birds of the Southwestern United States and Mexico

    Science.gov (United States)

    Mora, Miguel A.

    1997-01-01

    The hypothesis that migratory birds accumulate persistent organochlorine pesticides (POPs) during the winter in Latin America has been prevalent for many years, particularly since 1,1,1-trichloro-2,2–bis(p-chlorophenyl)ethane (DDT) was banned in the United States in 1972. It has been suggested that peregrine falcons (Falco peregrinus), black-crowned night herons (Nycticorax nycticorax), white-faced ibises (Plegadis chihi), various migratory waterfowl and shorebirds, and other avian species accumulate higher concentrations of POPs while on migration or on their wintering grounds in Latin America. Nonetheless, the data obtained thus far are limited, and there is no clear pattern to suggest that such accumulation occurs on a widespread basis. In this review wildlife contaminant studies conducted along the U.S.-Mexico border and throughout Mexico are discussed. The results for the most part seem to indicate that no major accumulation of 2,2-bis(p-chlorophenyl)-1,1-dichloroethylene) (DDE), the most persistent organochlorine compound, has occurred or been reported for most parts of Mexico. The majority of the DDE values in birds from Mexico were similar to those reported in birds from the southwestern United States during the same years. More work needs to be done, particularly in those cotton-producing areas of Mexico where DDT was applied heavily in the past (e.g., Chiapas and Michoacan). Because DDT is still used for malaria control and may still be used in agriculture in Chiapas, this state is probably the one where most migrant species would still be at a significant risk of increased accumulation of DDE and DDT.

  16. 75 FR 9281 - General Provisions; Revised List of Migratory Birds

    Science.gov (United States)

    2010-03-01

    ..., Collared, Charadrius collaris--Texas (AOU 1998); Pond-Heron, Chinese, Ardeola bacchus--Alaska (AOU 2000...) for the name change: Barn-Owl, Common, Tyto alba, becomes Owl, Barn (AOU 1989, 1998); Bittern, Chinese..., Intermediate, Mesophoyx intermedia (Monroe and Sibley 1993); Night-Heron, Malay, Nycticorax melanolophus...

  17. Major Rehabilitation Effort, Mississippi River, Locks and Dams 2-22: Illinois Waterway from LA Grange to Lockport Locks and Dams: Iowa, Illinois, Missouri, Minnesota and Wisconsin.

    Science.gov (United States)

    1989-03-01

    Demographics Services Center. Madison, Wt. Unpublished Source. - IS-36 (I0 00 ) 1*1 L (Baox) mammozqY&0 KTMES8TnfeTastigLcs edo EIS-7 NaIS~ton t L/D10 (986... redhead . Numerous bird species also utilize this reach. A rookery consisting of great blue, little blue, and black-crowned night herons is located at...lesser scaup, ringneck, goldeneye, canvasback, and redhead . Breeding ducks include wood duck, mallard, and blue-winged teal. 3.146 Marsh and shorebirds

  18. Response of roseate tern to a shoreline protection project on Falkner Island, Connecticut

    Science.gov (United States)

    Rogers, C.J.; Spendelow, J.A.; Guilfoyle, Michael P.; Fischer, Richard A.; Pashley, David N.; Lott, Casey A.

    2007-01-01

    subterranean channels, especially in the main revetment area, made it difficult to measure chick growth and productivity as had been done for more than 12 years prior to construction. Also, observations of color-banded adults that were unable to locate and feed their young inside the main revetment, and of adults returning to courtship behavior and renesting after having hatched chicks from their initial clutches, indicated that a minimum of 20% of the chicks (mostly first hatched A-chicks, which usually have high rates of survival to fledging) that entered the main revetment died after doing so in 2001. The mortality rate of Roseate Tern chicks that entered the secondary revetment on the southwest shelf, however, was not unusually high in 2001. In an attempt to reduce the likelihood of nesting and chick losses in these sub-colonies, a research team led by the USGS in 2002-2003 did not put nest boxes on the northeast and east shelf areas where previous losses had been high. However, losses of tern eggs and young chicks to predatory Black-crowned Night Herons (Nycticorax nycticorax) were so great in 2002?2003 that few Roseate Tern chicks survived long enough to move into the main revetment area and little comparative survival data were collected. The USFWS continues to remove predatory night herons, to monitor the location and success of nesting Roseate Terns and to fill in some of problem areas near the tern nests in the main revetment. The extensive chick-searching fieldwork and observational procedures used by the USGS-led research team to determine the growth and survival of the Roseate Tern chicks at Falkner Island were not used in 2004?2005. The number of chicks lost in the revetment during these years is not known. Without additional fill, loss of chicks of this endangered species in the main revetment may rise again even though the night heron predation problem has been reduced.

  19. The foraging behaviour of herons and egrets on the Magela Creek flood plain, Northern Territory

    International Nuclear Information System (INIS)

    Recher, H.F.; Holmes, R.T.

    1982-03-01

    Five species of diurnal herons are common on the Magela Creek flood plain and forage along the edges of natural and artifical waterbodies both inside and outside the Ranger Uranium Project Area. The species of heron differ in the kinds and sizes of prey they take, their foraging location, degree of sociality and foraging behaviour. Because it takes relatively large fish, the Great Egret, E. alba, is most likely to be affected by any contamination of the aquatic environment by heavy metals or radionuclides. The Nankeen Night Heron, Nycticorax caledonicus is also abundant on the flood plain and probably feeds on large fish and frogs. The other herons take smaller or immature prey or hunt mostly in terrestrial habitats and are therefore less likely to be affected by contamination of the aquatic environment

  20. Baseline report - tall upland shrubland at the Rocky Flats Environmental Technology Site

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    Rocky Flats Environmental Technology Site (Site) is located on the Colorado Piedmont east of the Front Range between Boulder and Golden. At an elevation of approximately 6,000 feet, the Site contains a unique ecotonal mixture of mountain and prairie plant species, resulting from the topography and close proximity to the mountain front. The Buffer Zone surrounding the Industrial Area is one of the largest remaining undeveloped areas of its kind along the Colorado Piedmont. A number of plant communities at the Site have been identified as increasingly rare and unique by Site ecologists and the Colorado Natural Heritage Program (CNHP). These include the xeric tallgrass prairie, tall upland shrubland, wetlands, and Great Plains riparian woodland communities. Many of these communities support populations of increasingly rare animals as well, including the Preble`s meadow jumping mouse, grasshopper sparrow, loggerhead shrike, Merriam`s shrew, black crowned night heron, and Hops blue and Argos skipper butterflies. One of the more interesting and important plant communities at the Site is the tall upland shrubland community. It has been generally overlooked by previous Site ecological studies, probably due to its relatively small size; only 34 acres total. Although mentioned in a plant community ordination study conducted by Clark et al. and also in the Site baseline ecological study, few data were available on this plant community before the present study.

  1. DDE in birds' eggs: Comparisons of two methods for estimating critical levels

    Science.gov (United States)

    Blus, L.J.

    1984-01-01

    The sample egg technique and eggshell thickness-residue regression analysis were comparatively evaluated as tools in estimating critical levels of DDE in birds? eggs that seriously affect reproductive successa nd population starts....In comparing critical values of DDE that were derived from the two methods, the estimates were lower using the sample egg technique for both the Brown Pelican (3 ?g/g vs 8 ?g/g) and the Black-crowned Night-Heron (12?g/g/ vs 54 ?g/g) assuming a critical value of eggshell thinning at 20%....Extension of the regression line beyond the eggshell thickness-DDE residue data base is likely to result in spurious critical values of DDE. When sufficient thickness and residue data are available for estimating critical values of DDE from the regression equation, the estimates are meaningful but are likely to be inflated because adverse effects unrelated to eggshell thinning such as parental behavior and embryotoxicity unrelated to eggshell deficiencies are not taken into account.....Establishing critical levels of pollutants in eggs and tissues is a necessary procedure in assessing effects of these chemicals on individuals and populations of sensitive species. There are inherent difficulties in quantifying the effects of any pollutant on population trends and declines in productivity. The sample egg technique is apparently a more sensitive method for estimating critical levels of DDE, but some subjective interpretation is required for results obtained by both methods.

  2. Baseline report - tall upland shrubland at the Rocky Flats Environmental Technology Site

    International Nuclear Information System (INIS)

    1997-03-01

    Rocky Flats Environmental Technology Site (Site) is located on the Colorado Piedmont east of the Front Range between Boulder and Golden. At an elevation of approximately 6,000 feet, the Site contains a unique ecotonal mixture of mountain and prairie plant species, resulting from the topography and close proximity to the mountain front. The Buffer Zone surrounding the Industrial Area is one of the largest remaining undeveloped areas of its kind along the Colorado Piedmont. A number of plant communities at the Site have been identified as increasingly rare and unique by Site ecologists and the Colorado Natural Heritage Program (CNHP). These include the xeric tallgrass prairie, tall upland shrubland, wetlands, and Great Plains riparian woodland communities. Many of these communities support populations of increasingly rare animals as well, including the Preble's meadow jumping mouse, grasshopper sparrow, loggerhead shrike, Merriam's shrew, black crowned night heron, and Hops blue and Argos skipper butterflies. One of the more interesting and important plant communities at the Site is the tall upland shrubland community. It has been generally overlooked by previous Site ecological studies, probably due to its relatively small size; only 34 acres total. Although mentioned in a plant community ordination study conducted by Clark et al. and also in the Site baseline ecological study, few data were available on this plant community before the present study

  3. Biodiversity assessment at Department of Atomic Energy (DAE) campus, Kalpakkam

    International Nuclear Information System (INIS)

    Jahir Hussain, K.; Satpathy, K.K.; Prasad, M.V.R.; Ramesh, T.; Selvanayagam, M.

    2008-01-01

    A rapid assessment of biodiversity in the DAE campus, Kalpakkam was carried out. The entire DAE campus of 3000 acres, at Kalpakkam was divided into four representative plots comprising of different landscapes namely (1) undisturbed area with dense vegetation, (2) building area, (3) water bodies with riparian cover and (4) sandy area with meager vegetation for inventorying of charismatic terrestrial/semi-aquatic fauna viz., Mammals, Birds, Reptiles, Amphibians and Butterflies. For birds, early morning surveys were made whereas for mammals evening and night surveys were followed. Midday sampling was followed for butterflies and other animals. Each plot was surveyed twice in a week over a period of one year (April 07' to March 08'). Totally 128 species of animals were identified during the survey and it has highlighted the potential of biodiversity in the campus. The diversity of butterflies is remarkable. Twenty-two butterfly species were encountered. Frogs, toads, lizards and snakes are also diverse. Five species of frogs and one species of toad were recorded. Lizards are more diverse than snakes. Nine species of lizards were encountered. Calotus versicolor is abundant followed by common skink. Totally five species of snakes were recorded. Among them Common bronzedback and Green Vine Snake were predominant. Seventy species of birds were recorded during the survey period. Black crowned night heron, Common house crow, Great cormorant, Oriental white ibis, Painted stork, Cattle egret, Common mynah are more common. Sixteen species of mammals were encountered during the survey. Wild cattle, Jackal, Jungle cat, Toddy cat, Crested porcupine and Indian civet are the major wildlife found. Indian civet and Crested porcupine are elusive animals that are diminishing from wild and their presence at this campus is an indication of less human intervention. (author)

  4. INDIRECT EFFECT OF EXTREME FLOODING: DISAPPEARANCE OF WADING BIRDS ROOST CAUSED BY VEGETATION TURN

    Czech Academy of Sciences Publication Activity Database

    Rajchard, J.; Balounová, Z.; Novák, R.; Kindlmann, Pavel

    2007-01-01

    Roč. 26, č. 1 (2007), s. 64-67 ISSN 1335-342X R&D Projects: GA AV ČR IAA6093105; GA AV ČR(CZ) KSK6005114 Keywords : extreme flooding * night heron * spoonbill * little egret * shrubs Subject RIV: EH - Ecology, Behaviour Impact factor: 0.085, year: 2005

  5. 50 CFR 10.13 - List of Migratory Birds.

    Science.gov (United States)

    2010-10-01

    ... flavicollis [Chinese (see Yellow)] Least, Ixobrychus exilis Schrenck's, Ixobrychus eurhythmus Yellow... leucocephalus Golden, Aquila chrysaetos White-tailed, Haliaeetus albicilla EGRET, Cattle, Bubulcus ibis Chinese..., Nycticorax nycticorax Japanese, Gorsachius goisagi [Malay (see Malayan)] Malayan, Gorsachius melanolophus...

  6. Review of Kenya bird records 2011–2014

    African Journals Online (AJOL)

    Grey Crowned Crane Balearica regulorum. N: c. 40 Nairobi NP 20 Oct 2012 (BF, FN, KP, MD). c. 200 Brookside Dairies, Ruiru 29 Jan 2014 (FN). Black Crowned Crane Balearica pavonina. 40+ along road north of Todenyang 15 Aug ..... 1 Sabaki bridge 21 July 2011 (EH). Accepted by the EARC as the 3rd Kenya record .

  7. Polychlorinated Biphenyl (PCB congener concentrations in aquatic birds. Case study: Ilha Grande Bay, Rio de Janeiro, Brazil

    Directory of Open Access Journals (Sweden)

    ALDO PACHECO FERREIRA

    2013-01-01

    Full Text Available Livers from 108 birds found prostrate or dead in Ilha Grande Bay between 2005 and 2010 were analyzed for 16 PCB congeners (IUPAC numbers 8, 18, 28, 31, 52, 77, 101, 118, 126, 128, 138, 149, 153, 169, 170, and 180. The species analyzed were Egretta caerulea (Linnaeus 1758, Nycticorax nycticorax (Linnaeus 1758, Egretta thula (Molina 1782, and Ardea cocoi (Linnaeus 1766. The analysis were performed using Origin software (7.5, 2004 with a significant level of p<0.05. Data were checked for adherence to the standard assumptions of parametric tests using the Kolmogorov-Smirnov test for normality and the Levene's test for homogeneity of variances. This has revealed differences in concentration for some congeners. Results indicate relatively low PCBs contamination in aquatic birds, but it is implied the close relationship of environmental contamination, showing potential power of widespread biological and mutagenic adverse effects in trophic levels, and therefore, signalling risk to human health.

  8. The component helminth community in six sympatric species of Ardeidae.

    Science.gov (United States)

    Navarro, Pilar; Lluch, Javier; Font, Enrique

    2005-08-01

    We studied the helminth communities in 6 sympatric species of Ardeidae (Ixobrychus minutus (Linnaeus, 1766), Nycticorax nycticorax (Linnaeus, 1758), Bubulcus ibis (Linnaeus, 1758), Egretta garzetta (Linnaeus, 1766), Ardea cinerea (Linnaeus, 1758), and Ardea purpurea (Linnaeus, 1766)) from "La Albufera de Valencia," Spain. The survey revealed 13 species of helminth parasites: 5 digeneans, 2 cestodes, and 6 nematodes. The component helminth communities of the Ardeidae examined are depauperate and conform to the pattern typically found in isolationist communities, probably because of their high trophic dependence on a few prey species. Evenness was positively correlated with richness and abundance, but host body weight was not correlated with the number of helminth species or with the total number of helminths. Ardea cinerea is more heavily infected than E. garzetta by Apharyngostrigea cornu, and B. ibis is more heavily infected than both Ardea cinerea and E. garzetta by Desportesius spinulatus. Apharyngostrigea cornu was positively associated with Desmidocercella numidica and D. spinulatus in A. cinerea.

  9. Host reproductive phenology drives seasonal patterns of host use in mosquitoes.

    Directory of Open Access Journals (Sweden)

    Nathan D Burkett-Cadena

    2011-03-01

    Full Text Available Seasonal shifts in host use by mosquitoes from birds to mammals drive the timing and intensity of annual epidemics of mosquito-borne viruses, such as West Nile virus, in North America. The biological mechanism underlying these shifts has been a matter of debate, with hypotheses falling into two camps: (1 the shift is driven by changes in host abundance, or (2 the shift is driven by seasonal changes in the foraging behavior of mosquitoes. Here we explored the idea that seasonal changes in host use by mosquitoes are driven by temporal patterns of host reproduction. We investigated the relationship between seasonal patterns of host use by mosquitoes and host reproductive phenology by examining a seven-year dataset of blood meal identifications from a site in Tuskegee National Forest, Alabama USA and data on reproduction from the most commonly utilized endothermic (white-tailed deer, great blue heron, yellow-crowned night heron and ectothermic (frogs hosts. Our analysis revealed that feeding on each host peaked during periods of reproductive activity. Specifically, mosquitoes utilized herons in the spring and early summer, during periods of peak nest occupancy, whereas deer were fed upon most during the late summer and fall, the period corresponding to the peak in births for deer. For frogs, however, feeding on early- and late-season breeders paralleled peaks in male vocalization. We demonstrate for the first time that seasonal patterns of host use by mosquitoes track the reproductive phenology of the hosts. Peaks in relative mosquito feeding on each host during reproductive phases are likely the result of increased tolerance and decreased vigilance to attacking mosquitoes by nestlings and brooding adults (avian hosts, quiescent young (avian and mammalian hosts, and mate-seeking males (frogs.

  10. Reprodução de aves aquáticas (Pelicaniformes na ilha do Maracujá, estuário da Baía da Babitonga, litoral norte de Santa Catarina

    Directory of Open Access Journals (Sweden)

    Alexandre Venson Grose

    2014-02-01

    Full Text Available http://dx.doi.org/10.5007/2175-7925.2014v27n2p117 As aves aquáticas costumam reproduzir de modo agregado, formando grandes colônias reprodutivas com diferentes espécies. Este estudo descreve aspectos biológicos das aves aquáticas de uma colônia na ilha do Maracujá, no estuário da baía da Babitonga, litoral norte de Santa Catarina. Foram coletados dados sobre riqueza de espécies, abundância, cronologia reprodutiva, predação e distribuição dos ninhos na ilha. No período de setembro de 2010 a fevereiro de 2011, foram identificadas 15 espécies de aves aquáticas utilizando o local para alimentação e descanso, sendo que destas, cinco espécies se reproduziam na ilha (Nycticorax nycticorax, Nyctanassa violacea, Egretta caerulea, Phimosus infuscatus e Aramides cajanea. Foram registrados 154 ninhos ativos, sendo 79 ninhos de N. nycticorax, 14 ninhos de N. violacea, seis ninhos de P. infuscatus, cinco ninhos de E. caerulea e apenas um ninho de A. cajanea. A população estimada para o local foi de 308 indivíduos reprodutores, sendo que N. nycticorax foi a espécie mais abundante, correspondendo a 51% dos ninhos. Os meses com maior concentração de ninhos foram setembro, outubro e novembro. Além das aves aquáticas, também foram registradas quatro espécies de aves de rapina e carniceiras, as quais foram responsáveis por perdas de ovos e/ou filhotes, junto com Larus dominicanus. A ilha do Maracujá vem sendo utilizada para reprodução por pelo menos cinco espécies e sua proteção merece atenção, a fim de garantir a manutenção e possibilidade de ampliação desse sítio reprodutivo.

  11. ORNITHOLOGICAL OBSERVATIONS ON THE VÂLCELE BASIN DURING FEBRUARY 2013 – JANUARY 2014

    Directory of Open Access Journals (Sweden)

    Adrian Mestecăneanu

    2014-06-01

    Full Text Available In this paper are showed the results of the researches performed during February 2013 – January 2014 on the avifauna from the Vâlcele Basin. The 65 observed species belong to 13 orders, Passeriformes being the richest (33 species. Anseriformes and Charadriiformes (each with 7 species were the best represented among the wetland birds. 5 species (Podiceps cristatus, Phalacrocorax carbo, Anas platyrhynchos, Fulica atra, and Larus argentatus cachinnans/michahellis were euconstant and 2 species (Anas platyrhynchos and Fulica atra were eudominant. Anas platyrhynchos counted most individuals in a month in December; in July were no individuals. Fulica atra had the most number in September; it was absent in May. For the Vâlcele Basin avicoenose, Anseriformes and Gruiformes were the overdominat orders and, inside the Anseriformes order, Anas platyrhynchos was overdominant species. 7 species (Egretta alba, Nycticorax nycticorax, Ciconia ciconia, Chlidonias hybridus, Alcedo atthis, Picus canus, and Lanius collurio are in the Annex I of the Birds Directive.

  12. An Analysis of the Population Dynamics of Selected Avian Species--With Special References to Changes During the Modern Pesticide Era

    Science.gov (United States)

    Henny, C.J.

    1972-01-01

    The impact of pesticides on the mortality rates and recruitment rates of nongame birds during the last 25 years was evaluated by studying the population dynamics of 16 species. A mathematical model showing the relations between population parameters that yielded stable populations was developed. The information needed for the model included (1) mortality rate schedule (obtained from recoveries of banded birds), (2) recruitment rates, and (3) the age of sexual maturity. The rate of recruitment necessary for a stable population and/or the annual rate of change (increase or decrease) in population levels were estimated. Population parameters were compared to determine whether changes had occurred between time periods (i.e., 1925-45 vs. 1946-65). The great horned owl, red-shouldered hawk, sparrow hawk, osprey, barn owl, Cooper's hawk, red-tailed hawk, great blue heron, blackcrowned night heron, brown pelican, barn swallow, chimney swift, blue jay, blackcapped chickadee, cardinal, and robin were subjected to this analysis. No increase in postfledging mortality rates in any of the species was detected during the last 25 years (since 1945). Since there was no evidence of increased mortality rates it was concluded that accelerated declines in several of the species studied resulted from lowered reproductive success. Mortality rates were found to have decreased in the Cooper's hawk, sparrow hawk, great blue heron, and brown pelican and this was associated with a decrease in shooting pressure. Evidence of lower recruitment rates was found in the brown pelican, osprey, Cooper's hawk, red-shouldered hawk, and sparrow hawk. No changes in recruitment rates were noted in the red-tailed hawk, great horned owl, great blue heron, or barn owl. Information on recruitment rates was not available for comparison with the other species although rates of recruitment essential for a stable population were estimated. This work will provide the basis for making comparisons in future studies

  13. The austral peregrine falcon: Color variation, productivity, and pesticides

    Science.gov (United States)

    Ellis, D.H.

    1985-01-01

    The austral peregrine falcon (Falco peregrinus cassini) was studied in the Andean foot- hills and across the Patagonian steppe from November to December 1981. The birds under study (18 pairs) were reproducing at or near normal (pre-DDT) levels for other races. Pesticide residues, while elevated, were well below the values associated with reproductive failure in other populations. With one exception, eggshells were not abnormally thin. The peregrine falcon in Patagonia exhibits extreme color variation. Pallid birds are nearly pure white below (light cream as juveniles), whereas normally pigmented birds are black-crowned and conspicuously barred with black ventrally. Rare individuals of the Normal Phase display black heads, broad black ventral barring, and warm reddish-brown ventral background coloration.