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1.
Graham M.  Lenton 《Ibis》1984,126(2):188-197
Moult in Malayan Barn Owls Tyto alba was studied in two pairs of wild collected captive birds and from feathers taken from nest sites throughout peninsular Malaysia.
Post-juvenile captive birds moulted nearly to completion prior to first breeding, beginning with P6 at a mean age of 301.5 days. This contrasted with the only other study of moult in captive Barn Ow-Is in Germany when moult began at an age of 400 days, and then continued for a protracted period of two years separated by a suspension of moult during the normal breeding season.
The complex sequence of moult in primaries and secondaries both in the Malayan and German birds was similar.
Moult among adult Malayan birds in the wild showed a broad and somebyhat irregular seasonal trend With lower incidence during peak breeding periods.  相似文献   

2.
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   

3.
For migratory species, the success of population reintroduction or reinforcement through captive‐bred released individuals depends on survivors undertaking appropriate migrations. We assess whether captive‐bred Asian Houbara Chlamydotis macqueenii from a breeding programme established with locally sourced individuals and released into suitable habitat during spring or summer undertake similar migrations to those of wild birds. Using satellite telemetry, we compare the migrations of 29 captive‐bred juveniles, 10 wild juveniles and 39 wild adults (including three birds first tracked as juveniles), examining migratory propensity (proportion migrating), timing, direction, stopover duration and frequency, efficiency (route deviation), and wintering and breeding season locations. Captive‐bred birds initiated autumn migration an average of 20.6 (±4.6 se) days later and wintered 470.8 km (±76.4) closer to the breeding grounds, mainly in Turkmenistan, northern Iran and Afghanistan, than wild birds, which migrated 1217.8 km (±76.4), predominantly wintering in southern Iran and Pakistan (juveniles and adults were similar). Wintering locations of four surviving captive‐bred birds were similar in subsequent years (median distance to first wintering site = 70.8 km, range 6.56–221.6 km), suggesting that individual captive‐bred birds (but not necessarily their progeny) remain faithful to their first wintering latitude. The migratory performance of captive‐bred birds was otherwise similar to that of wild juveniles. Although the long‐term fitness consequences for captive‐bred birds establishing wintering sites at the northern edge of those occupied by wild birds remain to be quantified, it is clear that the pattern of wild migrations established by long‐term selection is not replicated. If the shorter migration distance of young captive‐bred birds has a physiological rather than a genetic basis, then their progeny may still exhibit wild‐type migration. However, as there is a considerable genetic component to migration, captive breeding management must respect migratory population structure as well as natal and release‐site fidelity.  相似文献   

4.
We investigated reproductive regulation in male Rufous-winged Sparrows, Aimophila carpalis, a Sonoran Desert passerine that breeds after irregular summer rains. Field and captive data demonstrate that increased photoperiod stimulates testicular development in March and maintains it until early September. Free-living birds caught in July and placed on captive long days (16L: 8D) maintained developed testes for up to 7 months, and free-living birds caught in September, during testicular regression, redeveloped testes when placed on captive long days, indicating that these birds were still photosensitive. Captive birds on long days maintained testicular development when exposed to temperatures mimicking those occurring during regression in free-living birds. In free-living birds, testicular development was observed during spring and summer, but unless this was associated with rainfall, breeding (indicated by juveniles) did not occur. Large increases in plasma luteinizing hormone (LH) in free-living males were correlated with heavy rainfall in July/August, when the birds bred, and in November, when they did not breed. In captive birds, plasma LH concentrations were unresponsive to photoperiodic changes, but may have responded to social cues. Plasma prolactin concentrations were directly correlated with photoperiod in free-living birds, but an effect of photoperiod on prolactin secretion was not seen in captive birds. It is concluded that male Rufous-winged Sparrows use long photoperiods to stimulate and maintain testicular development, but exposure to long photoperiods does not terminate breeding by inducing absolute photorefractoriness. The specific timing of reproductive behaviors is apparently determined by elevated plasma LH coinciding with long day stimulated gonad development.  相似文献   

5.
Projects to rehabilitate confiscated animals must carefully consider the risks of disease when determining whether to release these animals back into the wild or to incorporate them into captive breeding programs. Avipox and paramyxovirus type 1 (PMV-1) infections are important causes of morbidity and mortality during rehabilitation of confiscated houbara bustards (Chlamydotis undulata macqueenii). This paper presents key findings of an intensive health monitoring program (physical condition, hematology, serology, endoscopy, microbiology, and virology) of two flocks of houbara bustards that survived outbreaks of septicemic avipox and PMV-1 respectively. Mortality in each flock from avipox and PMV-1 infections were 47% and 25% respectively, and the clinicopathologic features and management of each outbreak are presented. Avipox and PMV-1 viruses were not isolated from surviving birds monitored monthly for 11 mo after initial infection nor were septicemic or diptheritic avipox and PMV-1 infections detected in the captive breeding collection into which surviving birds were ultimately integrated up to 24 mo later. Adenovirus was isolated from four birds during the study demonstrating that novel disease agents of uncertain pathogenicity may be carried latently and intermittently shed by confiscated birds. This paper demonstrates the risk of importing pathogens with illegally traded houbara bustards and reinforces the need for surveillance programs at rehabilitation centers for these birds. We recommend that confiscated houbara bustards integrated into captive breeding programs be managed separately from captive-bred stock. Other measures should include separate facilities for adult birds and rearing facilities for offspring derived from different stock lines and strict sanitary measures. Additionally, health monitoring of confiscated birds should continue after birds are integrated into captive flocks.  相似文献   

6.
The population of great hornbills (Buceros bicornis) in the United States is rapidly aging, and captive breeding efforts have not met population managers' expectations for a sustainable captive group. Little is known about the reproductive physiology of these birds. This study reports the first data on the re‐productive endocrinology of the great hornbill. The hormone profiles of the only pair of these birds that hatched a chick in the 1999–2000 breeding season are compared to the profiles of six other pairs of hornbills, from different institutions in the United States, that did not reproduce successfully that season. The study investigates the estradiol, corticosterone, and testosterone profiles of these seven pairs of birds, establishing a base of knowledge from which endocrine data may be used to improve the success of captive breeding programs. The estradiol profiles from this study indicate a difference in hormonal patterns between laying and non‐laying female great hornbills. Egg‐laying females had significantly higher estradiol concentrations during the breeding season than the non‐laying females (P<0.003). Testosterone concentrations of the males were not significantly different between the mates of egg‐laying and non‐egg‐laying females. The corticosterone concentrations tended to be lower in the females that laid eggs vs. the non‐egg‐laying group. The males of the egg‐laying pairs showed a significantly lower (P<0.036) corticosterone concentration than the non‐egg‐laying male pairs. This, combined with the extremely low corticosterone levels (compared to the other birds in the study) of the pair of hornbills that hatched a chick in the 1999–2000 breeding season, suggests that adrenal activity may play a role in the reproductive failure of some captive great hornbills. Zoo Biol 22:135–145, 2003. © 2003 Wiley‐Liss, Inc.  相似文献   

7.
从2006年到2008年间对黄嘴鹮鹳的饲养环境进行人工调节,采用焦点动物法和扫描取样法对黄嘴鹮鹳的繁殖行为、雏鸟的生长发育进行观察.结果表明,人工措施可使黄嘴鹮鹳在北京地区全年繁殖;亲鸟在育雏期共同养育雏鸟;雏鸟属晚成鸟,但与鹮类相比,在生长发育上有特异性,更接近于鹳.  相似文献   

8.
Asian Houbara Chlamydotis macqueenii numbers are declining as a result of unsustainable levels of hunting and poaching, with the main conservation response being population reinforcement through the release of captive‐bred birds. We assessed the contribution of captive breeding to the species’ conservation by examining the fates of 65 captive‐bred birds fitted with satellite transmitters and released during spring (March–May) and autumn (August) into breeding habitat in Uzbekistan. Of the released birds, 58.5% survived to October, the month favoured by Emirati hunters in Uzbekistan, but only 10.8% of those released survived the winter to return as subadults next spring. To mitigate and compensate for the loss of wild adults to hunting, the number of released birds needs to be an order of magnitude higher than hunting quotas (with a release of between 1640 and 1920 required for a hypothetical quota of 200), indicating that releases may be costly and do not remove the need for a biologically determined sustainable hunting quota.  相似文献   

9.
An important component of the restoration strategy for the critically endangered kaki or black stilt (Himantopus novaezelandiae) is captive breeding for release. Since 1981 1,879 eggs were collected from wild and captive pairs, with birds laying up to four clutches. Eggs were incubated artificially and most chicks reared by hand until released as juveniles (about 60 days) or sub‐adults (9–10 months). Because survival in captivity is a significant determinant of the number of birds available for release, we wished to identify sources of variation in mortality to assess potential impacts of management on productivity. Hatchability was 78% for captive‐laid eggs and 91% for wild‐laid eggs. Survival of hatched eggs was 82% by 10 months of age for both wild and captive birds. Most egg mortality occurred early in incubation and around hatching: the timing of mortality was unaffected by whether birds were captive or wild, hybrid or pure kaki, or when eggs were laid. Heavier hatchlings showed higher initial survival, as did chicks from wild parents. Hatchlings from fourth‐laid eggs showed lowest survival, even though hatchling mass tended to increase with hatch order. Survival of chicks subjected to major health interventions was 69% after 4 months. No differences in survival were found between different genders, hybrids and pure kaki, hand‐reared or parent‐reared birds, chicks hatching early or late in the season, different seasons, different‐sized groups of chicks, chicks reared in different brooders, juveniles kept in different aviaries, and chicks from subsequent clutches. Birds subjected to minor health interventions were equally likely to survive as healthy chicks (82%). Survival was high despite aggressive management (quadruple clutching and collecting late in the season). Differences between captive and wild birds suggest further improvements could be made to captive diet. Wide variation in hatchability between parent pairs substantiates the practice of breaking up poorly performing pairs. Zoo Biol 0:1–16, 2005. © 2005 Wiley‐Liss, Inc.  相似文献   

10.
The influence of pair bond status, age and sex on aggression rates in a flock of 84 captive Chilean flamingos at Zoo Atlanta was examined. Analysis showed no difference between aggression rates of male and female flamingos, but adult flamingos had higher rates of aggression than juveniles. There were also significant differences in aggression depending on pair bond status (single, same‐sex pair, male–female pair or group). Bonded birds were significantly more aggressive than single birds, which is consistent with the concept that unpaired birds are not breeding and do not need to protect pair bonds or eggs. Birds in typical pair bonds (male–female) and atypical pair bonds (same‐sex pairs or groups) exhibited similar rates of aggression. These results contribute to the existing body of research on aggression in captive flamingos. Zoo Biol 30:59–64, 2011. © 2010 Wiley‐Liss, Inc.  相似文献   

11.
About 10 per cent of birds'' eggs fail to hatch, but the incidence of failure can be much higher in endangered species. Most studies fail to distinguish between infertility (due to a lack of sperm) and embryo mortality as the cause of hatching failure, yet doing so is crucial in order to understand the underlying problem. Using newly validated techniques to visualize sperm and embryonic tissue, we assessed the fertility status of unhatched eggs of five endangered species, including both wild and captive birds. All eggs were classified as ‘infertile’ when collected, but most were actually fertile with numerous sperm on the ovum. Eggs of captive birds had fewer sperm and were more likely to be infertile than those of wild birds. Our findings raise important questions regarding the management of captive breeding programmes.  相似文献   

12.
The neuroendocrine conditioning of reproduction in birds could perform a very important role in captive breeding, especially in endangered species. Whereas in domestic and wild mammals pharmacological reproductive conditioning is well developed, in birds an effective method is not available. The aim of this study was to test the influence of a new slow-release GnRH analogue (buserelin acetate) implant on the reproductive activity of the Budgerigar (Melopsittacus undulatus), used as model species for captive-bred endangered birds. The effects were assessed by looking at reproductive parameters (egg-laying rate, egg fertility rate) and measuring excreted sex steroid metabolite concentrations in male and female birds. Modification of reproductive parameters and steroid metabolites excretion patterns were observed among birds administered with a GnRH analogue implant and maintained under artificial photoperiod (group I; 16L:8D). Implanted birds showed higher rates of egg-laying, potentially a higher proportion of fertile eggs and higher excreted steroid metabolite concentrations than birds maintained under natural photoperiod (group II; 10L:14D) and birds maintained under artificial photoperiod (group III; 16L:8D). Thus, it is concluded that the new slow-release GnRH analogue implant may represent an innovative and practicable treatment to rapidly induce reproductive activity in the Budgerigar, and that excreted sex hormone metabolites detection permits to monitor male and female gonadal activity.  相似文献   

13.
The White‐headed Duck is a globally threatened species historically recorded from Spain in the west to China in the east. It has suffered major population declines, local extinctions and range fragmentation. Several projects have attempted to reintroduce captive‐bred birds into parts of the former range in Europe, but with little success. Two captive stocks currently exist, one originating from Pakistan in 1968 and the other originating from Spain in 1982. This study compares the suitability of these captive stocks for specific reintroduction projects by using 11 microsatellite markers and mtDNA control region sequences to assess genetic differences between captive populations and wild birds from Spain and Greece. No significant population structure was found and all microsatellite alleles recorded in captive birds originating from Pakistan were also observed in the wild Spanish population. A higher diversity of alleles was observed in wild birds from Greece than from Spain, probably due to the effects of a strong bottleneck experienced in Spain in the 1970s. Compared with wild populations, both captive stocks have suffered a significant loss of diversity in microsatellites and mitochondrial DNA owing to founder effects and/or genetic drift, and therefore may not be well suited for release programmes. We recommend the development of a more diverse captive breeding programme based on birds taken from different areas of the range, in particular by supplementing the Spanish population with birds from North Africa. Our study shows the value of molecular tools in developing conservation programmes for threatened bird species and has implications for the design of recovery programmes.  相似文献   

14.
From 1995 to 1999, two species of endemic Hawaiian thrushes, `Oma`o (Myadestes obscurus) and Puaiohi (M. palmeri), were captive‐reared and re‐introduced into their historic range in Hawai`i by The Peregrine Fund, in collaboration with the U.S. Geological Survey–Biological Resources Division (BRD) and the Hawai`i State Department of Land and Natural Resources. This paper describes the management techniques that were developed (collection of wild eggs, artificial incubation, hand‐rearing, captive propagation, and release) with the non‐endangered surrogate species, the `Oma`o; techniques that are now being used for recovery of the endangered Puaiohi. In 1995 and 1996, 29 viable `Oma`o eggs were collected from the wild. Of 27 chicks hatched, 25 were hand‐reared and released into Pu`u Wa`awa`a Wildlife Reserve. Using the techniques developed for the `Oma`o, a captive propagation and release program was initiated in 1996 to aid the recovery of the endangered Puaiohi. Fifteen viable Puaiohi eggs were collected from the wild (1996–1997) to establish a captive breeding flock to produce birds for re‐introduction. These Puaiohi reproduced for the first time in captivity in 1998 (total Puaiohi chicks reared in captivity 1996–1998 = 41). In 1999, 14 captive‐bred Puaiohi were re‐introduced into the Alaka`i Swamp, Kaua`i. These captive‐bred birds reproduced and fledged seven chicks in the wild after release. This is the first endangered passerine recovery program using this broad spectrum of management techniques (collection of wild eggs, artificial incubation, hand‐rearing, captive‐breeding, and release) in which re‐introduced birds survived and bred in the wild. Long‐term population monitoring will be published separately [BRD, in preparation]. Zoo Biol 19:263–277, 2000. © 2000 Wiley‐Liss, Inc.  相似文献   

15.
This article discusses two related issues of the captive breeding and reintroduction of the Oriental pied hornbill (Anthracoceros albirostris) in order to increase its population in the natural habitats. Oriental pied hornbills were bred in Khao Kheow Open Zoo. Three pairs were separated and kept in breeding cages. Females occupied artificial nests between February and April 2005–2007. Eggs were laid and incubated between February and March each year from 2005 to 2007. Nestlings hatched in late March and left the nest in late April 2005–2007. Each breeding pair was fed with approximately 400 g of food each day. All three pairs reproduced resulting in mature offspring of seven in 2005, six in 2006, and five in 2007. Four of sixteen 3‐year‐old birds were randomly selected and equipped with a GPS receiver on their backs. Activities of the birds attached and unattached with GPS were not significantly different. The first two birds (one female, one male with GPS) were reintroduced on August 5, 2006, and another nine birds (four birds with GPS) were reintroduced on December 26, 2006. The average home range of these reintroduced birds was 0.13 km2. Their foods consisted of wild plants and animals in the home range. The first reintroduced pair was able to breed naturally by laying and hatching eggs in an artificial nest. Two juveniles left the nest in April 2008. These results indicate that both captive breeding and reintroduction are potentially important ways to increase the population of the Oriental pied hornbill in natural habitats. Zoo Biol 31:683‐693, 2012. © 2011 Wiley Periodicals, Inc.  相似文献   

16.
The immune system requires energetic and nutritional resources to optimally defend organisms against pathogens and parasites. Because resources are typically limited, immune function may require a trade-off with other physiologically demanding activities. Here, we examined whether photoperiodically induced seasonal states (breeding, molting, or nonbreeding) affected the cutaneous immune response of captive male house sparrows (Passer domesticus). To assess immune function in these birds, we injected the mitogen phytohemagglutinin (PHA) into the patagium and measured the resulting wing web swelling. Molting and nonbreeding birds had similar immune responses to PHA injection. However, males in a breeding state showed lower immune responses than both molting and nonbreeding birds even though they did not actually breed. We tested whether this decrease in the PHA swelling response in birds in a breeding state was due to elevated plasma concentrations of testosterone (T) by administering T to birds in a nonbreeding state. Contrary to some evidence in the literature, T did not suppress the response to PHA in house sparrows. Our data show that passerine birds show seasonal modulation in immune function, even in benign environmental conditions. However, even though T is often cited as a strong immunosuppressant, it is not fully responsible for this seasonal modulation.  相似文献   

17.
We used microsatellites to assess ongoing captive breeding and reintroduction programs of the lesser kestrel. The extent of genetic variation within the captive populations analysed did not differ significantly from that reported in wild populations. Thus, the application of widely recommended management practices, such as the registration of crosses between individuals in proper stud books and the introduction of new individuals into the genetic pools, has proven satisfactory to maintain high levels of genetic variation. The high rates of hatching failure occasionally documented in captivity can therefore not be attributed to depressed genetic variation. Even though genetic diversity in reintroduced populations did not differ significantly when compared to wild populations either, average observed heterozygosities and inbreeding coefficients were significantly lower and higher, respectively, when compared to the captive demes where released birds came. Monitoring of reproductive parameters during single-pairing breeding and paternity inference within colonial facilities revealed large variations in breeding success between reproductive adults. The relative number of breeding pairs that contributed to a large part of captive-born birds (50–56%) was similar in both cases (28.6 and 26.9%, respectively). Thus, the chances for polygyny (rarely in this study), extra-pair paternity (not found in this study) and/or social stimulation of breeding parameters do not seem to greatly affect the genetically effective population size. Independently of breeding strategies, the release of unrelated fledglings into the same area and the promotion of immigration should be mandatory to counteract founder effects and avoid inbreeding in reintroduced populations of lesser kestrels.  相似文献   

18.
Members of the order Psittaciformes (parrots and cockatoos) are among the most long-lived and endangered avian species. Comprehensive data on lifespan and breeding are critical to setting conservation priorities, parameterizing population viability models, and managing captive and wild populations. To meet these needs, we analyzed 83, 212 life history records of captive birds from the International Species Information System and calculated lifespan and breeding parameters for 260 species of parrots (71% of extant species). Species varied widely in lifespan, with larger species generally living longer than smaller ones. The highest maximum lifespan recorded was 92 years in Cacatua moluccensis, but only 11 other species had a maximum lifespan over 50 years. Our data indicate that while some captive individuals are capable of reaching extraordinary ages, median lifespans are generally shorter than widely assumed, albeit with some increase seen in birds presently held in zoos. Species that lived longer and bred later in life tended to be more threatened according to IUCN classifications. We documented several individuals of multiple species that were able to breed for more than two decades, but the majority of clades examined had much shorter active reproduction periods. Post-breeding periods were surprisingly long and in many cases surpassed the duration of active breeding. Our results demonstrate the value of the ISIS database to estimate life history data for an at-risk taxon that is difficult to study in the wild, and provide life history data that is crucial for predictive modeling of future species endangerment and proactively managing captive populations of parrots.  相似文献   

19.
FRANK CEZILLY  ALAN R. JOHNSON 《Ibis》1995,137(4):543-546
Data on re-mating between and within breeding seasons were collected between 1983 and 1994 as part of a long-term study of the Greater Flamingo Phoenicopterus ruber roseus in the Camargue, southern France. Flamingos have bred in the Rhône delta for centuries and since 1972 have done so annually on an artificial island in the Etang du Fangassier. A sample of chicks has been ringed each year since 1977; many of these birds were later observed back at the breeding site and were used in this study. The mate-switching rate between consecutive breeding seasons was 98.3%. This result is contrary to what has been reported from captive flocks where extensive mate fidelity occurred between consecutive breeding seasons. Mate-switching also was observed in the Camargue within breeding seasons, following breeding failure, and seems to be linked to male breeding strategy in response to the need to synchronize hatching and the limited energy supply of breeding females. The absence of a long-term pair bond in Greater Flamingos contrasts with current views on the evolution of mate fidelity in relation to longevity in birds.  相似文献   

20.
Recent research has shown that large flamingo flocks are more likely to experience reproductive success than small flocks and that there is a positive relationship between behavioral stimulation from group displays and reproductive success. This study compares the group displays and reproductive success in a captive flock of Caribbean flamingos over 6 years at the National Zoological Park. Birds were added to the flock in two different years. In each case, the flock produced fertile eggs during the breeding season following the addition of new birds. Furthermore, the addition of new birds in 1988, and then again in 1991, significantly increased group display activity over the previous year when the flock size was lower. That the addition of birds stimulated group display activity suggests an alternative management strategy for promoting reproduction in captivity: separate birds in a flock and then reunite them prior to the breeding season. © 1994 Wiley-Liss, Inc.  相似文献   

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