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1.
Lead poisoning and organ levels of the non-essential heavy metals lead, cadmium and mercury of seven free-ranging golden eagles (Aquila chrysaetos) from the European Alps, and of one 23-year-old captive golden eagle are reported. All birds were found dead or moribund during the years 2000 and 2001 in Austria, Germany and Switzerland. One golden eagle from Switzerland with extraordinarily high lead residues in its liver and kidney was clearly identified as lethally lead poisoned. Another bird from the same region was found still alive and died in a wildlife rehabilitation center, showing lead residues in its organs known for acute lead poisoning with detrimental physiological effects, such as nervous disorders and the inhibition of the hemoglobine synthesis. Concentrations of cadmium, mercury and lead residues in the organs of the other five free-ranging birds, and in the long-lived captive golden eagle, were low and represent the natural background levels in birds of prey of the terrestrial food web. This is the first published report of lead poisoning in golden eagles from Switzerland. Sources for lead poisoning in golden eagles in the Alpine region are discussed.  相似文献   

2.
ABSTRACT.   To assess population trends of Harlequin Ducks ( Histrionicus histrionicus ) in Rhode Island (U.S.A.), we analyzed Christmas Bird Counts and other historical surveys and also conducted surveys during the winter of 2005–2006. We estimated sex and age ratios, evaluated the effects of tidal regime and time of day on survey precision, and quantified habitat use. The population in Rhode Island experienced logistic growth from 1976 to 2004, with approximately 150 birds now wintering at three primary sites in the state. We estimated that the current ratio of males to females in the region was 1.6:1 (62% males) and that 13% of males were first-winter birds. Most Harlequin Ducks were observed in rocky habitats within 50 m of the shore or offshore islands. We detected the greatest numbers of birds, with the least amount of variation, during morning surveys at low tide, suggesting that this may be the most appropriate time for population monitoring. Increases in the Rhode Island population and male-biased sex ratios may indicate a local population recovery resulting from a hunting ban initiated in 1990. Although most Harlequin Ducks in eastern North America winter in Maine, the population in Rhode Island represents one of the largest in the southern part of their range.  相似文献   

3.
Waterfowl are the natural reservoir of all influenza A viruses, which are usually nonpathogenic in wild aquatic birds. However, in late 2002, outbreaks of highly pathogenic H5N1 influenza virus caused deaths among wild migratory birds and resident waterfowl, including ducks, in two Hong Kong parks. In February 2003, an avian H5N1 virus closely related to one of these viruses was isolated from two humans with acute respiratory distress, one of whom died. Antigenic analysis of the new avian isolates showed a reactivity pattern different from that of H5N1 viruses isolated in 1997 and 2001. This finding suggests that significant antigenic variation has recently occurred among H5N1 viruses. We inoculated mallards with antigenically different H5N1 influenza viruses isolated between 1997 and 2003. The new 2002 avian isolates caused systemic infection in the ducks, with high virus titers and pathology in multiple organs, particularly the brain. Ducks developed acute disease, including severe neurological dysfunction and death. Virus was also isolated at high titers from the birds' drinking water and from contact birds, demonstrating efficient transmission. In contrast, H5N1 isolates from 1997 and 2001 were not consistently transmitted efficiently among ducks and did not cause significant disease. Despite a high level of genomic homology, the human isolate showed striking biological differences from its avian homologue in a duck model. This is the first reported case of lethal influenza virus infection in wild aquatic birds since 1961.  相似文献   

4.
In 1971, an outbreak of a hemorrhagic disease occurred in captive and free-ranging white-tailed deer (Odocoileus virginianus) in Mammoth Cave National Park, Kentucky, Clinical signs and gross pathological lesions were consistent with those of epizootic hemorrhagic disease and bluetongue, as were serological and histopathological findings for samples sent to other laboratories. The infection rate among the 104 captive deer was 88-92%, and that among the free-ranging Park deer appeared to be similar. Mortality was negligible in the Park deer, but 65 (62%) of the captive deer died. The deaths were bimodally distributed over a 36-day period, and the mortality rate decreased from 97-100% for deer clinically ill during the first 17 days of the outbreak to 58% for deer first exhibiting clinical signs on day 16 or later. Mortality was equal in males and females, but less in yearlings than among fawns or adults. Winter mortality among survivors of the initial outbreak was associated with low ambient temperatures and sometimes fungal and bacterial abscesses, possibly sequelae or complications of the hemorrhagic disease. The pregnancy and birth rates among surviving does appeared to be normal.  相似文献   

5.
Wyoming toads (Bufo baxteri) that died from January 1989 to June 1996 were submitted to the Wyoming State Veterinary Laboratory (Laramie, Wyoming, USA) for postmortem evaluation. These consisted of 108 free-ranging toads and 170 animals from six captive populations. Ninety-seven (90%) of 108 free-ranging toad carcasses were submitted during September and October. From 1989 to 1992, 27 (77%) of 35 mortalities in the captive populations occurred in October, November, and December. From 1993 to 1996, mortality in captive toads occurred without a seasonal pattern and coincided with changes in hibernation protocols that no longer mimicked natural cycles. Cause of mortality was determined in 147 (53%) of the 278 cases. Mycotic dermatitis with secondary bacterial septicemia was the most frequent diagnosis in 104 (71%) of 147 toads. Basidiobolus ranarum was found by microscopic examination of skin sections in 100 (96%) of 104 of these mortalities. This fungus was isolated from 30 (56%) of 54 free-ranging and 24 (48%) of 50 captive toads. This research documents the causes of mortality for both free-ranging and captive endangered Wyoming toads over a 7 yr period.  相似文献   

6.
Little is known about baseline concentrations of adrenal hormones and hormonal responses to stress in sea ducks, although significant population declines documented in several species suggest that sea ducks are exposed to increased levels of environmental stress. Such declines have been observed in geographically distinct harlequin duck populations. We performed an adrenocorticotropic hormone (ACTH) challenge to evaluate adrenal function and characterize corticosterone concentrations in captive harlequin ducks and investigated the effects of capture, surgery, and short term confinement on corticosterone concentrations in wild harlequin ducks. Harlequin ducks responded to the ACTH challenge with an average three-fold increase in serum corticosterone concentration approximately 90 min post injection, and a four- to five-fold increase in fecal glucocorticoid concentration 2 to 4 h post injection. Serum corticosterone concentrations in wild harlequin ducks increased within min of capture and elevated levels were found for several hours post capture, indicating that surgery and confinement maintain elevated corticosterone concentrations in this species. Mean corticosterone concentrations in wild harlequin ducks held in temporary captivity were similar to the maximum response levels during the ACTH challenge in captive birds. However, large variation among individuals was observed in responses of wild birds, and we found additional evidence suggesting that corticosterone responses varied between hatch year and after hatch year birds.  相似文献   

7.
Fifty-three newly captive birds of prey were tested serologically for neutralizing antibodies against rabies virus, using a fluorescent focus inhibition test. No significant antibody titers were detected with this sensitive and specific technique in any of these birds. This study supports the contention that free-ranging birds of prey are of limited importance in the epidemiology of rabies.  相似文献   

8.
The cheetah (Acinonyx jubatus) has been considered a paradigm for disease vulnerability due to loss of genetic diversity. This species monomorphism has been suspected to be the basis for their general poor health and dwindling populations in captivity. North American and South African captive populations have high prevalences of hepatic veno-occlusive disease, glomerulosclerosis, gastritis, and systemic amyloidosis, diseases that are rare in other species. Unusually severe inflammatory reactions to common infectious agents have also been documented in captive cheetahs. The current study compared disease prevalences in free-ranging Namibian cheetahs with those in two captive populations of similar ages. The occurrence of diseases in the free-ranging population was determined from 49 necropsies and 27 gastric biopsies obtained between 1986 and 2003 and compared with prevalences in 147 North American and 80 South African captive cheetahs. Except for two cheetahs, the free-ranging population was in robust health with only mild lesions present, in contrast with significantly higher prevalences in the captive populations. Despite widespread heavy Helicobacter colonization in wild cheetahs, only 3% of the free-ranging population had moderate to severe gastritis, in contrast with 64% of captive cheetahs. No severe inflammatory reactions to viral infections were detected in the free-ranging animals. Because free-ranging Namibian cheetahs are as genetically impoverished as captive cheetahs, these findings caution against attributing loss of fitness solely to genetic factors and attest to the fundamental importance of extrinsic factors in wildlife health.  相似文献   

9.
Twenty-eight Harlequin Ducks (Histrionicus histrionicus) and 26 Barrow's Goldeneyes (Bucephala islandica) were captured in Prince William Sound, Alaska, between 1 and 15 March 2005. Blood was collected for quantification of element concentrations, prevalence of antibodies to several viruses, and hemoparasite prevalence and identification. Although we found selenium concentrations that have been associated with selenosis in some birds (>or=2.0 ppm ww), our findings contribute to a growing literature describing relatively high selenium in apparently healthy birds in marine environments. Avian influenza virus antibodies were detected in the plasma of 28% of the ducks. No antibodies against adenovirus, reovirus, or paramyxovirus 1 were detected. Several hemo-parasite species were identified in 7% of ducks. Our findings are similar to those in other free-living marine waterfowl and do not indicate unusual concerns for the health of these species in this area in late winter.  相似文献   

10.
Little is known about baseline concentrations of adrenal hormones and hormonal responses to stress in sea ducks, although significant population declines documented in several species suggest that sea ducks are exposed to increased levels of environmental stress. Such declines have been observed in geographically distinct harlequin duck populations. We performed an adrenocorticotropic hormone (ACTH) challenge to evaluate adrenal function and characterize corticosterone concentrations in captive harlequin ducks and investigated the effects of capture, surgery, and short term confinement on corticosterone concentrations in wild harlequin ducks. Harlequin ducks responded to the ACTH challenge with an average three-fold increase in serum corticosterone concentration approximately 90 min post injection, and a four- to five-fold increase in fecal glucocorticoid concentration 2 to 4 h post injection. Serum corticosterone concentrations in wild harlequin ducks increased within min of capture and elevated levels were found for several hours post capture, indicating that surgery and confinement maintain elevated corticosterone concentrations in this species. Mean corticosterone concentrations in wild harlequin ducks held in temporary captivity were similar to the maximum response levels during the ACTH challenge in captive birds. However, large variation among individuals was observed in responses of wild birds, and we found additional evidence suggesting that corticosterone responses varied between hatch year and after hatch year birds.  相似文献   

11.
During the period from 1982 to 1991, 863 captive and 32 wild capercaillies (Tetrao urogallus) were necropsied. The most common cause of death in captive capercaillies was necrotizing enteritis, diagnosed in 110 (13%) birds. Of these, 31 (28%) birds also had necrotizing lesions in the liver. Necrotizing gastritis occurred in 29 birds, two of which had concurrent necrotizing enteritis. In the capercaillies with necrotizing enteritis, Clostridium perfringens type A was isolated more frequently and in larger numbers than in birds which died from other causes. Thus, Clostridium perfringens type A may be of etiological importance in necrotizing enteritis. Necrotizing enteritis was not diagnosed in wild capercaillies.  相似文献   

12.
Necropsy findings from natural deaths in free living and captive stitchbirds (Notiomystis cincta) were examined over a 3 yr period (November 1991-94) to establish whether disease was an important factor in translocation failures and captive breeding programs undertaken by the New Zealand Department of Conservation. Fresh and fixed material from seven free-living birds and 11 captive birds were examined and were compared with those of a retrospective study of archival material from captive and wild birds collected over a 13 yr period (1979-91). The causes of death in both the present and retrospective study showed a similar pattern with aspergillosis and aspiration pneumonia being the most significant cause of mortality in captive birds. Aspergillosis was diagnosed as the cause of death in 11 of 31 stitchbirds from Mt Bruce; eight of these deaths occurred in the winter months (June-August). The other causes of death in captive birds included trauma, coccidiosis, and sporadic bacterial infections. Hemosiderosis and airsacculitis were common histological findings in most of the wild and captive stitchbirds examined.  相似文献   

13.
ABSTRACT.   We studied the movements and foraging effort of radio-marked Steller's Eiders ( Polysticta stelleri ) and Harlequin Ducks ( Histrionicus histrionicus ) to evaluate habitat quality in an area impacted by industrial activity near Dutch Harbor, Alaska. Foraging effort was relatively low, with Steller's Eiders foraging only 2.7 ± 0.6 (SE) hours per day and Harlequin Ducks 4.1 ± 0.5 hours per day. Low-foraging effort during periods of high-energetic demand generally suggests high food availability, and high food availability frequently corresponds with reductions in home range size. However, the winter ranges of Harlequin Ducks did not appear to be smaller than usual, with the mean range size in our study (5.5 ± 1.1 km2) similar to that reported by previous investigators. The mean size of the winter ranges of Steller's Eiders was similar (5.1 ± 1.3 km2), but no comparable estimates are available. Eutrophication of the waters near Dutch Harbor caused by seafood processing and municipal sewage effluent may have increased populations of the invertebrate prey of these sea ducks and contributed to their low-foraging effort. The threat of predation by Bald Eagles ( Haliaeetus leucocephalus ) that winter near Dutch Harbor may cause Steller's Eiders and Harlequin Ducks to move further offshore when not foraging, contributing to an increase in range sizes. Thus, the movement patterns and foraging behavior of these ducks likely represent a balance between the cost and benefits of wintering in a human-influenced environment.  相似文献   

14.
15.
We evaluated the possibility of deriving primary cell cultures from tissue biopsies taken in field conditions from six threaten endemic Chilean species of free-ranging mammals. Biopsies were taken either by ear punching or darts fired to animals and hold in hypothermic conditions (4 degrees C) in defined salt solution for time periods ranging from 0 to 7 d before biopsy samples reached the cell culture laboratory. Previously, holding times were evaluated in experimental cows in controlled conditions. Two enzymatic treatments, collagenase alone or collagenase followed by tripsin, were used to disaggregate tissues for cell culture. We found that ear notches and dart-derived biopsies can be storaged at 4 degrees C for 1 wk and still yield primary cultures. For dart-derived biopsies, there was an invert correlation between length of cold storage and cellular viability in culture. Healthy fibroblast cell lines were obtained in 92% of the biopsies taken despite the origin (punch or biopsy). We are not aware of similar study for free-ranging animals, especially for the use of darting system to biopsy wild terrestrial mammals, we believe that our results could help for a more widespread implementation of these procedures in the practice of ex situ conservation.  相似文献   

16.
Although the impact of blood parasite infections on passerine birds is potentially great, little is known of their pathologic effects. We studied Haemoproteus danilewskyi in experimentally infected captive and naturally infected free-ranging blue jays (Cyanocitta cristata) to determine patterns of infection and examine the pathologic effects of the parasite on the host. Physiologic changes, such as elevated numbers of lymphocytes, heterophils, basophils, eosinophils, and monocytes and decreased packed cell volume in the peripheral blood were associated with the erythrocytic phase of experimental infections of captive juvenile jays. Sublethal pathologic changes associated with the pre-erythrocytic phase of infections were observed in the liver, lung, and spleen. Schizonts were observed in the pulmonary capillaries of a 1 yr old jay necropsied 31 days post-inoculation, but not in 20 juvenile jays necropsied 57 days post-inoculation. In free-ranging naturally infected jays plasma protein concentration increased with density of natural infections.  相似文献   

17.
Selenium is a trace element of concern in the McLeod River basin downstream from two recently-closed coal mines in west-central Alberta, Canada. Aquatic birds breed on streams in the area and may be exposed to excessive amounts of selenium through their diets. In this article, we present the results of a dietary-based assessment of the risk that selenium may pose to two aquatic bird species, the American Dipper (Cinclus mexicanus) and the Harlequin Duck (Histrionicus histrionicus), on one of the coal mine–affected streams, the Gregg River. The study consisted of (1) a literature-based toxicity assessment, (2) simulation of selenium exposure in the diets and eggs of the two species, and (3) a risk assessment that coupled information on toxicity and exposure. Diet and egg selenium concentrations associated with a 20% hatch failure rate were 6.4 and 17 μ g · g?1 dry wt, respectively. Simulated dietary selenium concentrations were about 2.0–2.5 μ g · g?1 higher on the Gregg River than on reference streams for both species. Simulated predicted egg concentrations averaged 2.0 and 1.4 μ g · g?1 higher on the Gregg River than on reference streams for American Dippers and Harlequin Ducks, respectively. When simulated dietary concentrations were considered, hatch failure rates on the Gregg River were predicted to average 12% higher in American Dippers and 8% higher in Harlequin Ducks than at reference streams. Corresponding values were only 3% for both species when predicted egg concentrations were used. Elevated levels of selenium in insects in some of the reference streams were unexpected and raised a question as to whether aquatic birds have evolved a higher tolerance level for dietary selenium in these areas.  相似文献   

18.
We conpared three fecal steroid metabolite assays for their usefulness in detecting pregnalcy among free-ranging Rocky Mountain bighorn sheep (Ovis canadensis canadensis) from Bighorn Canyon National Recreation Area, Wyoming and Montana (USA) and captive bighorn ewes at ZooMontana in Billings, Montana. Fecal samples were collected from 11 free-ranging, radio-collared bighorn ewes in late January-May 2001 and from 20 free-ranging, radio-collared ewes in late March to mid-May 2002. Free-ranging ewes were monitored the following spring to determine whether or not they lambed. In addition, two captive ewes were studied at ZooMontana. With three exceptions, free-ranging bighorn ewes that produced lambs had nonspecific progesterone metabolite (iPdG) levels of >1800 ng/g feces and iPdG levels >7000 ng/gm feces when samples were collected between early March and mid-May. Samples collected earlier in the year were inconclusive. One false negative was suspected to be the result of sample collection error. Of the captive ewes, nonspecific pregnanediol-3alpha-glucuronide (PdG) and iPdG followed a predictable curve over the course of the 180-day pregnancies. We conclude that estrone conjugates are not useful in diagnosing pregnancy; however, fecal steroid analysis of PdG and iPdG can be used to accurately determine pregnancy and reproductive function in bighorn sheep. This holds great potential as a noninvasive technique for understanding the role of reproductive disease in wild bighom sheep.  相似文献   

19.
Highly pathogenic avian influenza (HPAI) H5N1 virus circulates among a variety of free-ranging wild birds and continually poses a threat to animal and human health. During the winter of 2010-2011, we surveyed Korean wild bird habitats. From 728 fresh fecal samples, 14 HPAI H5N1 viruses were identified. The isolates phylogenetically clustered with other recently isolated clade 2.3.2 HPAI H5N1 viruses isolated from wild birds in Mongolia. All HPAI-positive fecal samples were analyzed by DNA barcoding for host-species identification. Twelve of the 14 HPAI-positive samples were typed as Mandarin Duck (Aix galericulata). The high incidence of HPAI subtype H5N1 viruses in wild Mandarin Duck droppings is a novel finding and underscores the need for enhanced avian influenza virus surveillance in wild Mandarin Ducks. Further investigation of the susceptibility of Mandarin Ducks to HPAI H5N1 clade 2.3.2 virus would aid the understanding of HPAI ecology and epidemiology in wild birds.  相似文献   

20.
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, which undertakes marathon 30,000 km hemispheric migrations annually. In spring, migrant birds forage voraciously on horseshoe crab eggs in Delaware Bay in the eastern USA before departing to breed in Arctic polar deserts. From 1997 to 2002 an increasing proportion of knots failed to reach threshold departure masses of 180-200 g, possibly because of later arrival in the Bay and food shortage from concurrent over-harvesting of crabs. Reduced nutrient storage, especially in late-arriving birds, possibly combined with reduced sizes of intestine and liver during refuelling, had severe fitness consequences for adult survival and recruitment of young in 2000-2002. From 1997 to 2002 known survivors in Delaware Bay were heavier at initial capture than birds never seen again, annual survival of adults decreased by 37% between May 2000 and May 2001, and the number of second-year birds in wintering flocks declined by 47%. Population size in Tierra del Fuego declined alarmingly from 51,000 to 27,000 in 2000-2002, seriously threatening the viability of this subspecies. Demographic modelling predicts imminent endangerment and an increased risk of extinction of the subspecies without urgent risk-averse management.  相似文献   

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