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1.
Fifty cranes, consisting of 46 sandhill (Grus canadensis) and four whooping cranes (Grus americana), were studied. Eighteen sandhill cranes and the four whooping cranes were naturally infected with disseminated visceral coccidiosis (DVC). The remaining sandhill cranes were chicks experimentally infected with oocysts of Eimeria reichenowi and/or E. gruis; five chicks served as controls. There were no clinical signs attributed to respiratory infection. Necropsy of naturally infected adult birds revealed nodules in many organs, including the lung, air sacs, trachea and nares. Artificially infected sandhill cranes and the whooping crane chicks that died from DVC had congestion and consolidated areas in the lung with frothy fluid in the airways. Grossly visible nodules were observed from 10 days postinoculation. Granulomatous pneumonia and tracheitis were observed with light microscopy. Lesions were associated with merogonic and gametogonic stages of eimerian coccidia. Granulomas and granulomatous foci contained parasitized large mononuclear cells. Merogonic stages were seen in lymphoid cells by ultrastructural examination. Oocysts were observed in the trachea and bronchial mucosa and admixed with exudate in the airways, indicating that crane eimerians can complete their life cycle at these sites. Of the few eimeriid coccidia that have extraintestinal stages of development in birds and mammals, only the species in cranes complete their life cycle in both the digestive and respiratory tracts.  相似文献   

2.
The enteric flora of captive whooping cranes (Grus americana) and sandhill cranes (Grus canadensis) has not been well described, despite its potential importance in the understanding of both the normal condition of the intestinal physiology of these animals and the altered colonization within disease states in these birds. Nineteen whooping cranes and 23 sandhill cranes housed currently at the Calgary Zoo or its affiliated Devonian Wildlife Conservation Centre (DWCC) in Calgary, Alberta were sampled from October 2004–February 2005 by collecting aerobic and anaerobic cloacal swabs from each bird. There were seven major groupings of bacteria isolated from both species of crane. Gram‐positive cocci, coliforms, and gram‐negative bacilli were the most prevalent types of bacteria isolated for both crane species, with Escherichia coli, Enterococcus faecalis, and Streptococcus Group D, not Enterococcus the bacterial species isolated most commonly. There was a significant difference in the average number of isolates per individual between the two crane species but no differences between age or gender categories within crane species. Campylobacter sp. were isolated from five whooping cranes. The potential zoonotic pathogen Campylobacter jejuni was isolated from one whooping crane and C. upsaliensis was isolated from a second. Three other isolates were unspeciated members of the Campylobacter genus and likely belong to a species undescribed previously. The evaluation of the enteric cloacal flora of whooping cranes and sandhill cranes illustrates that differences exist between these two closely related crane species, and highlights the potential implications these differences may have for current practices involving captive wildlife. Zoo Biol 0:1–13, 2007. © 2007 Wiley‐Liss, Inc.  相似文献   

3.
Electrophoretic analysis of proteins yielded evidence on the relationships of species of cranes and on genetic diversity within populations of some species. Diversity within the Greater Sandhill crane and a Florida population of the Florida Sandhill crane was similar to that of most other vertebrates, but diversity was low in the Mississippi Sandhill crane, in the Okefenokee population of the Florida Sandhill crane, and within the Siberian and Sarus cranes. Diversity was surprisingly high among whooping cranes, whose number dropped to less than 25 early in this century. Phylogenetic analysis, using both character state and distance algorithms, yielded highly concordant trees for the 15 species. The African crowned cranes (Balearica) were widely divergent from all other cranes. Species of Anthropoides, Bugeranus, and Grus clustered closely but sorted into two lineages: a Whooper Group consisted of the whooping, common, hooded, black-necked, white-naped, and red-crowned cranes of genus Grus; and a Sandhill Group included the Sandhill, Siberian, Sarus, and Brolga cranes of genus Grus, the wattled crane of genus Bugeranus, and the Demoiselle and blue cranes of genus Anthropoides.  相似文献   

4.
In contrast with isosporoid species of coccidia that have established extraintestinal phases of development, the eimeriids, except for a few species, generally have been considered inhabitants of the intestinal tract. Eimeria infection in sandhill cranes (Grus canadensis) and whooping cranes (G. americana) may result in disseminated visceral coccidiosis. Nodules were observed in the oral cavity of 33% (n = 95) of the G. canadensis at the Patuxent Wildlife Research Center (PWRC) in Laurel, MD. Necropsy of six of the afflicted cranes revealed granulomatous nodules in many tissues and organs. Histologic studies disclosed protozoan organisms morphologically resembling schizonts in the granulomas, and endogenous stages of coccidia were present in the intestines of four birds. Fecalysis of three of four sandhill cranes yielded oocysts of E. reichenowi and E. gruis. Only E. reichenowi-type oocysts were recovered from a dead whooping crane sample. Domestic broiler chicks each intubated with about 1 times 106 pooled sporulated oocysts of E. reichenowi and E. gruis were not infected. Exposure of six incubator-hatched and hand-reared sandhill crane chicks to oocysts artificially (two chicks) and naturally (four chicks) resulted in typical infection of intestinal epithelium with invasion of subepithelial tissues extending to the muscular layer and widespread extraintestinal development. Asexual and sexual stages occurred primarily in macrophages in the liver, spleen, heart, and lung. In the lung, oocysts were found in bronchial exudate and epithelial lining cells. Six of ten G. canadensis chicks, one adult G. americana, and three of five G. americana chicks that died naturally at PWRC had disseminated visceral coccidiosis.  相似文献   

5.
Coccidia of whooping cranes   总被引:2,自引:0,他引:2  
Coccidial oocysts were observed in 6 of 19 fecal samples from free-ranging whooping cranes (Grus americana) and 4 of 16 samples from captive whooping cranes. Eimeria gruis occurred in four free-ranging whooping cranes and E. reichenowi in two free-ranging and two captive whooping cranes. Fecal samples from two captive cranes contained oocysts of Isospora lacazei which was considered a spurious parasite. Oocysts of both species of Eimeria were prevalent in fecal samples collected from three free-ranging Canadian sandhill cranes (G. canadensis rowani) from whooping crane wintering grounds in Texas. These coccidia were prevalent also in fecal samples from 14 sandhill cranes (of 4 subspecies) maintained in captivity at the Patuxent Wildlife Research Center in Maryland.  相似文献   

6.
We obtained blood smears from 114 Florida sandhill crane (Grus canadensis pratensis) chicks in Osceola and Lake Counties, Florida, USA, during 1998-2000. Leucocytozoon grusi was observed in 11 (10%) chicks; Haemoproteus antigonis was observed in eight (7%) chicks; and three (3%) chicks were infected with Haemoproteus balearicae. One chick infected with H. balearicae suffered from severe anemia (packed cell volume = 13%) and was later found moribund. At necropsy this bird also had severe anemia and damage to the heart possibly due to hypoxia. This is the first report of H. balearicae in free-ranging North American cranes.  相似文献   

7.
Endangered whooping cranes (Grus americana) have been produced in captivity for reintroduction programs since the 1980s, using techniques such as artificial insemination, multiple clutching, and captive-rearing to speed recovery efforts. Chicks are often hand-reared (HR) by caretakers in crane costumes, socialized into groups and released together, unlike parent-reared (PR) cranes that are raised individually by a male/female crane pair and released singly. HR cranes historically exhibit greater morbidity rates during development than PR cranes, involving musculoskeletal and respiratory system disease, among others. We hypothesized that HR crane chicks exhibit a higher baseline fecal glucocorticoid metabolite (FGM) concentrations during the development compared with PR chicks. Fecal samples were collected between 15 and 70 days of age from HR (n = 15) and PR (n = 8) chicks to test for differences in FGM concentrations using a radioimmunoassay technique following ethanol extraction for steroids. Linear mixed model analysis suggests increasing age of the chick was associated with an increase in FGM (p < .001). Analysis also supported the interaction between rearing strategy and sex of the crane chick (p < .01). Female PR chicks had greater FGM concentrations than all other groups (PR male, p < .01; HR female, p < .001; and HR male, p < .001). This result suggests that there may be an effect of rearing strategy on stress physiology of whooping crane chicks, especially among females. Further research is needed to investigate whether the FGM concentrations are reflective of true differences in stress physiology of young cranes and whether this may impact health and conservation success.  相似文献   

8.
The non-invasive method of determining the sex of chicks after hatching based on the DNA isolated from capillary vessels of allantois of the egg-shell membranes was demonstrated on four crane species (Gruinae, Aves), which were bred in the Crane Breeding Centre of the Oka Nature Reserve in 2009–2012. Using the EE0.6 molecular marker of sex, the gender of 26 Siberian (Grus leucogeranus), 15 Red-crowned (G. japonensis), 4 Common (G. grus) and 1 Demoiselle (Anthropoides virgo) crane chicks was identified. This method can be recommended for determining the sex of chicks and the ratio of sexes in cranes that reproduce both in captivity and natural populations.  相似文献   

9.
Florida sandhill cranes (Grus canadensis pratensis) were conditioned to confinement 6 hr/day for 7 days. On day 8, each bird's jugular vein was catheterized, blood samples were drawn, and each crane was confined for 6 hr. Using a randomized, restricted cross-over design, cranes were injected intravenously with either 0.9% NaCl solution or ACTH (cosyntropin; Cortrosyn; 0.25 mg). During the 6 hr of confinement, fecal samples (feces and urine) were collected from each of five cranes immediately after defecation. Individual fecal samples were collected approximately at hourly intervals and assayed for corticosterone. We showed previously that serum corticosterone did not vary significantly following saline injection, but peaked significantly 60 min after ACTH injection. Maximal fecal corticosterone concentrations (ng/g) were greater (P < 0.10; median 1087 ng/g) following ACTH stimulation compared to maximal fecal corticosterone concentrations at the end of acclimation (day 7; median 176) and following saline treatment (median 541). In cranes under controlled conditions, fecal corticosterone concentration reflects serum corticosterone levels, fecal corticosterone, Grus canadensis pratensis, sandhill cranes, serum corticosterone levels.  相似文献   

10.
Studies of artificial insemination of cranes and cryoconservation of their semen have been carried out in the nursery of rare species at the Oka Biosphere Reserve for many years. The criterion of successful cryoconservation of the semen is the obtaining of fertilized eggs after artificial insemination by the thawed semen. An experiment is described on artificial insemination of females of the white-naped crane Grus vipio by the frozen–thawed semen of the Siberian white crane G. leucogeranus after one-year storage of semen in liquid nitrogen. As a result, an interspecific hybrid of cranes was obtained, which confirmed the possibility of producing a bank of cryoconserved crane semen. The use of the white-naped crane females was due to the absence of conspecific males and unavailability of Siberian white crane females. Problems of artificial insemination and cryoconservation of semen of rare crane species are discussed.  相似文献   

11.
Studies of artificial insemination of cranes and cryoconservation of their semen have been carried out in the nursery of rare species at the Oka Biosphere Reserve for many years. The criterion of successful cryoconservation of the semen is the obtaining of fertilized eggs after artificial insemination by the thawed semen. An experiment is described on artificial insemination of females of the white-naped crane Grus vipio by the frozen–thawed semen of the Siberian white crane G. leucogeranusafter one-year storage of semen in liquid nitrogen. As a result, an interspecific hybrid of cranes was obtained, which confirmed the possibility of producing a bank of cryoconserved crane semen. The use of the white-naped crane females was due to the absence of conspecific males and unavailability of Siberian white crane females. Problems of artificial insemination and cryoconservation of semen of rare crane species are discussed.  相似文献   

12.
The genetic diversity of the founders of an artificial population of the Siberian crane Grus leucogeranus Pallas (rare species of cranes) was characterized using 10 microsatellite loci. It was established that the allelic diversity (on average, 5.9 alleles per locus) and genic (H O = 0.739) diversity of the Siberian crane is rather high and comparable with the estimations for natural populations of different crane species. Genetic passportization of the birds (119 individuals) from the register of the Siberian crane International Studbook was carried out at the initial stage. The efficiency of genetic passportization for individual identification, identification of the origin, paternity analysis, and exclusion of inbreeding was demonstrated in Siberian cranes under natural mating and artificial insemination. Cases of natural reproduction in pairs of Siberian cranes imprinted to the human and continuous storage of spermatozoa in the female reproductive ducts were registered.  相似文献   

13.
Chicks can convey information about their needs with calls. But it is still unknown if there are any universal need indicators in chick vocalizations. Previous studies have shown that in some species vocal activity and/or temporal-frequency variables of calls are related to the chick state, whereas other studies did not confirm it. Here, we tested experimentally whether vocal activity and temporal-frequency variables of calls change with cooling. We studied 10 human-raised Siberian crane (Grus leucogeranus) chicks at 3–15 days of age. We found that the cooled chicks produced calls higher in fundamental frequency and power variables, longer in duration and at a higher calling rate than in the control chicks. However, we did not find significant changes in level of entropy and occurrence of non-linear phenomena in chick calls recorded during the experimental cooling. We suggest that the level of vocal activity is a universal indicator of need for warmth in precocial and semi-precocial birds (e.g. cranes), but not in altricial ones. We also assume that coding of needs via temporal-frequency variables of calls is typical in species whose adults could not confuse their chicks with other chicks. Siberian cranes stay on separate territories during their breeding season, so parents do not need to check individuality of their offspring in the home area. In this case, all call characteristics are available for other purposes and serve to communicate chicks’ vital needs.  相似文献   

14.
Hematophagous insects can negatively affect the reproductive success of their vertebrate hosts. To determine the influence of hematophagous insects on endangered vertebrates requires specially designed programs that minimize disturbance to the hosts and address problems associated with their small populations. We developed and evaluated a surveillance program for black flies potentially affecting a population of whooping cranes (Grus americana) introduced to central Wisconsin, U.S.A. In one of the few studies to survey host‐seeking female black flies and their immature stages concurrently, we processed nearly 346,000 specimens and documented 26 species, of which only two, Simulium annulus and Simulium johannseni, were attracted to nesting whooping cranes. Attempts to assess black fly populations with artificial nests and real crane eggs were unsuccessful. Carbon‐dioxide traps performed well in describing black fly taxa on the landscape. However, the number of black flies at whooping crane nests was consistently higher than the number captured in carbon‐dioxide traps. The carbon‐dioxide traps poorly described the presence/absence, population fluctuations, and periodicity of black flies at whooping crane nests. The weak performance of the carbon‐dioxide traps might have resulted from microhabitat differences between trap locations and nests or from Simulium annulus and Simulium johannseni using sensory cues in addition to carbon dioxide to find hosts. Choice of trapping techniques, therefore, depends on the information required for the particular study objectives.  相似文献   

15.
The Aransas-Wood Buffalo population (the only non-reintroduced, migratory population) of endangered whooping cranes (Grus americana) overwinters along the Texas Gulf Coast, USA. Understanding whooping crane space use on the wintering grounds reveals essential aspects of this species' ecology, which subsequently assists with conservation. Using global positioning system telemetry data from marked whooping cranes during 2009–2017, we fit continuous-time stochastic process models to describe movement and home range using autocorrelated kernel density estimation (AKDE) and explored variation in home range size in relation to age, sex, reproductive status, and drought conditions. We used the Bhattacharyya coefficient of overlap and distance between home range centroids to quantify site fidelity. We examined the effects of time between winter home ranges and the sex of the crane on site fidelity using Bayesian mixed-effects beta regression. Winter whooping crane 95% AKDE home range size averaged 30.1 ± 45.2 (SD) km2 (median = 14.3, range = 1.1–308.6). Home ranges of sub-adult females were approximately 2 times larger than those of sub-adult males or families. As drought worsened, home ranges typically expanded. Between consecutive years, the home ranges of an adult crane exhibited 68 ± 31% overlap (site fidelity), but fidelity to winter sites declined in subsequent winters. The overlap of adult home ranges with the nearest unrelated family averaged 33 ± 28%. As a whooping crane aged, overlap with its winter home range as a juvenile declined, regardless of sex. By 4 years of age, a whooping crane had approximately 14 ± 28% overlap with its juvenile winter home range. Limited evidence suggested male whooping cranes return to within 2 km of their juvenile home range by their fifth winter. Previous data obtained from aerial surveys led ecologists to assume that whooping crane families normally used small areas (~2 km2) and expressed persistent site fidelity. Our analyses showed <8% of families had home ranges ≤2 km2, with the average area 15 times greater, and waning site fidelity over time. Our work represents an analysis of whooping crane home ranges for this population, identifying past misconceptions of winter space use and resulting in better estimates of space requirements for future conservation efforts.  相似文献   

16.
Identifying climatic drivers of an animal population's vital rates and locating where they operate steers conservation efforts to optimize species recovery. The population growth of endangered whooping cranes (Grus americana) hinges on juvenile recruitment. Therefore, we identify climatic drivers (solar activity [sunspots] and weather) of whooping crane recruitment throughout the species’ life cycle (breeding, migration, wintering). Our method uses a repeated cross‐validated absolute shrinkage and selection operator approach to identify drivers of recruitment. We model effects of climate change on those drivers to predict whooping crane population growth given alternative scenarios of climate change and solar activity. Years with fewer sunspots indicated greater recruitment. Increased precipitation during autumn migration signified less recruitment. On the breeding grounds, fewer days below freezing during winter and more precipitation during breeding suggested less recruitment. We predicted whooping crane recruitment and population growth may fall below long‐term averages during all solar cycles when atmospheric CO2 concentration increases, as expected, to 500 ppm by 2050. Species recovery during a typical solar cycle with 500 ppm may require eight times longer than conditions without climate change and the chance of population decline increases to 31%. Although this whooping crane population is growing and may appear secure, long‐term threats imposed by climate change and increased solar activity may jeopardize its persistence. Weather on the breeding grounds likely affects recruitment through hydrological processes and predation risk, whereas precipitation during autumn migration may influence juvenile mortality. Mitigating threats or abating climate change should occur within ≈30 years or this wild population of whooping cranes may begin declining.  相似文献   

17.
A female-specific DNA fragment (CSL-W; crane sex-linked DNA on W chromosome) was cloned from female whooping cranes (Grus americana). From the nucleotide sequence of CSL-W, a set of polymerase chain reaction (PCR) primers was identified which amplify a 227-230 bp female-specific fragment from all existing crane species and some other noncrane species. A duplicated versions of the DNA segment, which is found to have a larger size (231-235 bp) than CSL-W in both sexes, was also identified, and was designated CSL-NW (crane sex-linked DNA on non-W chromosome). The nucleotide similarity between the sequences of CSL-W and CSL-NW from whooping cranes was 86.3%. The CSL primers do not amplify any sequence from mammalian DNA, limiting the potential for contamination from human sources. Using the CSL primers in combination with a quick DNA extraction method allows the noninvasive identification of crane gender in less than 10 h. A test of the methodology was carried out on fully developed body feathers from 18 captive cranes and resulted in 100% successful identification.  相似文献   

18.
Understanding the influence of environmental stressors on daily nest survival of introduced birds is important because it can affect introduction success as well as the ability to evaluate introduction programs. For long-lived birds with low annual production, adjustment to local breeding conditions can take many years. We examined nest success rates of 2 introduced bird species, whooping crane (Grus americana) and trumpeter swan (Cygnus buccinator), in Wisconsin. Both species are long-lived with low annual reproductive rates. Trumpeter swans were established in our study area approximately 10 years before whooping cranes. We predicted that trumpeter swans would show less sensitivity to environmental stressors. We used daily nest survival rates (DNSRs) as our response variable to model several environmental parameters including weather, phenology, and ornithophilic black flies (Diptera: Simuliidae). Additionally, we examined the influence of captive history, age, release method, energetics, and nesting experience on whooping crane DNSRs. Daily nest survival of whooping cranes was the most sensitive to stressors. Trumpeter swan daily nest survival showed less sensitivity to the same stressors. Daily nest survival for both species peaked later in the nesting season, after 30 April and before 30 May. We also found that the daily nest survival rate (DNSR) for whooping cranes was potentially affected by captive exposure (measured by generations removed from the wild). Our results highlight the difficulties associated with conservation of long-lived birds with low annual productivity as they adjust to local breeding conditions and that nest phenology at the source location can determine how these conditions are interfaced. We recommend that the juxtaposition of source and introduction location nest phenology be considered prior to introduction site selection. Additionally, strategically selecting offspring from captive pairs with nest phenology similar to that of sympatric species at the introduction location should be considered. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.  相似文献   

19.
While agricultural intensification and expansion are major factors driving loss and degradation of natural habitat and species decline, some wildlife species also benefit from agriculturally managed habitats. This may lead to high population densities with impacts on both human livelihoods and wildlife conservation. Cranes are a group of 15 species worldwide, affected both negatively and positively by agricultural practices. While eleven species face critical population declines, numbers of common cranes (Grus grus) and sandhill cranes (Grus canadensis) have increased drastically in the last 40 years. Their increase is associated with higher incidences of crane foraging on agricultural crops, causing financial losses to farmers. Our aim was to synthesize scientific knowledge on the bilateral effects of land use change and crane populations. We conducted a systematic literature review of peer‐reviewed publications on agriculture‐crane interactions (n = 135) and on the importance of agricultural crops in the diet of cranes (n = 81). Agricultural crops constitute a considerable part of the diet of all crane species (average of 37%, most frequently maize (Zea mays L.) and wheat (Triticum aestivum L.)). Crop damage was identified in only 10% of all agriculture‐crane interactions, although one‐third of interactions included cranes foraging on cropland. Using a conceptual framework analysis, we identified two major pathways in agriculture‐crane interactions: (1) habitat loss with negative effects on crane species dependent on specific habitats, and (2) expanding agricultural habitats with superabundant food availability beneficial for opportunistic crane species. The degree to which crane species can adapt to agricultural land use changes may be an important factor explaining their population response. We conclude that multi‐objective management needs to combine land sparing and land sharing strategies at landscape scale. To support viable crane populations while guaranteeing sustainable agricultural production, it is necessary to include the perspectives of diverse stakeholders and streamline conservation initiatives and agricultural policy accordingly.  相似文献   

20.
A number of wildlife species have recovered from the brink of extinction to flourish and, in some cases, even become a commonly recognized urban species (e.g., Canada goose [Branta canadensis]). Broadly extirpated from much of their historical range in North America, the sandhill crane (Antigone canadensis) demonstrated this potential for population recovery. The trajectory of the eastern population of greater sandhill cranes is remarkable—perhaps as many as 90,000 cranes now occur throughout the same Great Lakes states that reported only dozens of birds less than a century ago. However, understanding future population growth of the species remains uncertain because breeding birds are increasingly exposed to the pressures of urban sprawl and a changing agricultural landscape. From 2009 to 2014 we investigated the survival of sandhill crane nests and young up to 11 weeks of age (the point at which they are capable of flight) in the core of the eastern population's range in central Wisconsin and at its peripheral extent in a rapidly developing urban region of northeastern Illinois, USA. We located crane nests via systematic surveys on foot and from helicopters, we then radio-tagged the young and monitored them until they died or were capable to sustained flight. Overall, young were more likely to hatch from nests in Illinois (60%) than in central Wisconsin (46%), regardless of differences in land cover surrounding the nest site. In contrast, the survivorship of young was positively correlated with urban land cover in both regions but higher in central Wisconsin (54%) than in northeast Illinois (27%). Overall, the probability of producing young was greater in landscapes with more urban development, regardless of region. We suggest that differences in predator composition, predator behavior, and crane density between rural and urban areas is the primary reason for the difference in crane productivity. Higher recruitment of sandhill cranes using urban landscapes may allow cranes to echo the population trajectory of urban Canada geese. We anticipate that sandhill cranes will continue to use urban landscapes, and likely expand their geographic range as breeding pairs benefit from the increased survivorship of young in those landscapes. © The Wildlife Society, 2019  相似文献   

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