Genetic diversity and relatedness in different generations of the Siberian crane (Grus leucogeranus Pallas) captive population

Eight variable microsatellite loci were analyzed in terms of studying the genetic structure of different generations of a captive population of a rare endemic Russian species, the Siberian crane (Grus leucogeranus Pallas). It was shown that the founding population of natural origin (15 birds) is characterized by high genetic diversity (N _A = 6.625, H _O = 0.767, H _E = 0.731) and a lack of relatedness (R = ?0.079). In the total sample of descendents of the founders (122 individuals from generations F₁, F₁/F₂, F₁/F₃, F₂, F₂/F₃), this characteristic level of genetic variation is being maintained; however, we observed a decrease in allelic richness in some generations (F₁/F₂, F₁/F₃, F₂). We found a low level of relatedness in the sample of descendents of the founders (F₁, F₁/F₂, F₁/F₃), while the relatedness was maximal (R = 0.302) in the descendents of the breeders of the first generation. A small sample of breeders related to each other of generations F₁ and F₂ (eight birds) does not represent the entire gene pool of the founders of the Siberian Crane captive population. In view of this, we discuss the need to form a new genetically heterogeneous generation of breeders that would also include Siberian Cranes from the almost extinct Western Siberian population.     

Variation of mitochondrial DNA D-loop sequences in the endangered Siberian crane Grus leucogeranus Pallas

To evaluate inter- and intra-populational divergence of the endangered Siberian crane a comparative analysis of mtDNA D-loop region (490 bp) sequences was performed for 17 captive cranes including 14 originating from the eastern and 3 from the central nesting area. Thirteen variable sites form 9 haplotypes, 6 belonging to the eastern nesting site individuals, 2 belonging to the central nesting site and one being common for both nesting areas. The haplotype network analysis did not show significant separation of these two groups. The data obtained could provide genetic grounds for the programs of restoration of the central nesting area population by captive breeding and reintroduction to the wild using the eastern nesting site population gene pool. These results could also be a basis for further evaluation of Siberian crane populations genetic divergence needed for its adequate protection.     

白鹤冷冻精液人工授精实验

为了探索鹤类精液冷冻保存和使用技术,2003～2005年,进行了白鹤(Grus leucogeranus)的冷冻精液保存及人工授精实验。使用Beltsville家禽精液稀释液作为白鹤精液稀释液,12%的二甲基亚砜(DMSO)为冷冻液。精液样本冷冻经过三个阶段的降温,最后保存在液氮中。成功保存了编号93001雄性白鹤精液36 支（0.2 ml/支）。冷冻精液在0~4℃冰水中解冻3~5 min,解冻后白鹤精液精子活率为29.3%±15.5%（n=16）,2004和2005年分别为92101号雌鹤产的两窝卵进行人工授精实验,2年共产卵5枚,其中1枚卵受精并成功孵化。实验发现在雌鹤产卵前一周和产卵期间每天输精,并增加每次输精量,同时在产完1枚卵后4 h内完成一次输精,效果最佳。     

Genetic differentiation in a captive population of the endangered Siberian crane (Grus leucogeranus Pall.)

DNA fingerprinting, followed by multivariate analysis of data, was used to characterize genetic heterogeneity in captive populations of the endangered Siberian and sandhill cranes. The genetic structure revealed reflected the natural population and species distributions. The relevant groups differed not only from each other, but also from interspecies and inter-population hybrids bred in captivity. In this study we have tested an approach to the analysis of population structure based on individual genotypes. Interpretation of fingerprinting data by means of the analytical system applied here is a useful and reliable procedure for the estimation of genetic relationships between individuals.     

莫莫格自然保护区白鹤秋季迁徙停歇期觅食生境选择

2008年秋季(10月8日—20日)及2009年秋季(9月20日—10月16日),通过样方法对觅食生境11个生态因子进行调查,利用卡方检验、资源选择指数和资源选择函数在莫莫格保护区对秋季迁徙停歇期白鹤觅食生境选择进行研究。结果表明,白鹤对距人为干扰源距离、植被密度、盖度、高度、植物性食物密度以及水深均具有选择性,但对宏观尺度干扰因子的选择性较低。其偏好觅食生境的特点为:距一级路>5000m,>二级路1500m以上,>三级路1000m以上,>居民点1000m以上,农田>1000m;植被密度20~50株/m2,盖度<10%,高度<20cm,扁杆藨草密度1~50株/m2,藨草密度1~10株/m2,水深40~60cm。白鹤秋季觅食生境资源选择函数为Logistic(P)=0.663+0.565×与一级道路距离+0.042×与二级道路距离+0.519×与三级道路距离+0.353×与居民点距离+0.169×与农田距离–0.455×植被密度–0.618×植被盖度–0.548×植被高度–0.158×扁杆藨草密度–0.404×藨草密度+0.920×水深,T(x)=eLogistic(p)/[1+eLogistic(p)],模型正确预测率为82.9%。     

近十年来鄱阳湖区越冬白鹤种群数量与分布

1998—2010年,该研究采用地面同步调查法在鄱阳湖区64个湖泊开展了越冬白鹤种群监测。结果表明,鄱阳湖区分布有稳定的越冬白鹤种群,鄱阳湖区越冬白鹤种群数量年平均值为(3108±849)只,2002年冬季达到最大值4004只;从2003年开始鄱阳湖区越冬白鹤数量表现出一定的年际波动,但变化幅度较小。共有46个湖泊被记录到有白鹤活动。其中,达到全球白鹤种群数量1%标准以上的湖泊达25个;白鹤数量接近或超过全球白鹤种群数量的40%,即1280只个体以上的湖泊包括鄱阳湖国家级自然保护区内的大汊池、蚌湖和蚕豆湖,以及保护区外的南湖。自然保护区涵盖了越冬白鹤的主要聚集湖泊。分布在自然保护区内的白鹤占鄱阳湖区越冬白鹤种群总数量的(66±27.3)%。保护区外分布的白鹤数量虽然总体呈下降趋势,但仍分布有一定数量的个体。     

Evaluation of the enteric microflora of captive whooping cranes (Grus americana) and sandhill cranes (Grus canadensis)

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.     

The ecology of the habitats, nesting, and migration of the eastern population of the siberian crane (Grus leucogeranus Pallas, 1773)

The structure of the distribution range and population of the Siberian crane in its regular breeding area in the northeastern Yakutian tundra are described, as well as the migration terms, intensity, routes, and stopover sites. The territorial pairs (71.7–97.1% of the summer population), which in 2006 were represented by the birds at ages of 8 to 21 years (mainly 20 years, accounting for 45.4%), constantly stayed on an area of 7.3–16.5 km² independently of their participation in breeding. The breeding success in this population varies from 4.3–8.7 to 65.0–83.3% and depends on the climatic conditions at the beginning of egg laying; these climatic conditions change rather unpredictably from year to year, as well as being seasonally unstable. This explains that fact that some generations in this population are particularly vulnerable to natural elimination factors because of their low numbers. Bird migration in Yakutia follows a narrow tunnel with the highest migratory intensity in the Middle Aldan Valley. In the fall, 30 to 50% of the entire population is visually recorded there.     

Coccidiosis of sandhill cranes (Grus canadensis) wintering in New Mexico

The feces of 212 sandhill cranes (Grus canadensis) collected in central New Mexico from October 1982 to January 1983 and from October 1983 to January 1984 were examined to determine the prevalence of coccidial oocysts. One hundred forty-five granulomatous nodules from the viscera of 64 cranes and samples of lung, small intestine, and large intestine from 58 birds were examined by light and transmission electron microscopy for the presence of intestinal or extraintestinal coccidiosis. Of the 212 fecal samples, 160 (75%) were positive for oocysts of Eimeria, including E. gruis in 139 (66%) and E. reichenowi in 118 (56%) of the samples. Eimeria bosquei sp. n. was found in two (approximately 1%) of the fecal samples. Subspheroid to ovoid oocysts of this new species are 19-27 X 14-19 (23.6 X 17.1) micrograms with ovoid sporocysts 10-14 X 7-11 (12.3 X 9.3) micrograms. A rough, heavily pitted outer oocyst wall, sporocyst residuum, Stieda and substieda bodies, and multiple polar bodies are present. The polar bodies, of varying sizes, always aggregate at the apex of the sporulated oocyst. An Adelina sp. was found in one (0.5%) crane. Coccidian developmental stages were found in the epithelium and lamina propria of the small and large intestine. Disseminated granulomatous nodules were found in the oral mucosa, esophagus, heart, descending aorta, liver, small intestine, mesenteries, and parietal peritoneum. Unique cell types resembling coccidian asexual and sexual stages were observed by light and electron microscopy in some of the nodules.     

Fecal corticoid monitoring in whooping cranes (Grus americana) undergoing reintroduction

We used radioimmunoassay to determine fecal corticoid concentrations and assess potential stress in 10 endangered whooping cranes (Grus americana) undergoing reintroduction to the wild. Fecal samples were collected shortly after hatching at a captive facility in Maryland, during field training in Wisconsin, and throughout a human‐led migration to Florida. After a 14‐day decline following hatching, fecal corticoid concentrations stabilized at baseline levels for the duration of the captive period, despite exposure to potentially stressful stimuli. Shipment of the cranes to the field training site was correlated with an eight‐ to 34‐fold increase in fecal corticoid concentrations, which returned to baseline levels within 1 week. Increases were positively correlated with age but not body weight at the time of shipping. Fecal corticoid concentrations during the training period increased slightly and exhibited greater variation than levels observed at the captive facility, but were well within expected norms based on previous studies. Fecal corticoid concentrations increased twofold following premigration physical examinations and placement of radiotransmitters, and persisted for up to 4 days before they returned to baseline levels. Though fecal corticoid concentrations and variation during the migration period were similar to training levels, there was an overall decline in fecal corticoid concentrations during the artificial migration. Acute stressors, such as capture, restraint, and severe storms, were associated with stress responses by the cranes that varied in accordance with lasting physical or psychological stimuli. The overall reintroduction process of costume‐rearing, ultralight aircraft habituation, training, and artificial migration was not associated with elevations in fecal corticoid concentrations suggestive of chronic stress. Zoo Biol 24:15–28, 2005. © 2005 Wiley‐Liss, Inc.     

Genetic variation in the midcontinental population of sandhill cranes,Grus canadensis

Three subspecies of sandhill crane (Grus canadensis) are recognized in the Midcontinental population, the lesser (Grus c. canadensis), Canadian (G. c. rowani), and greater (G. c. tabida). Blood samples collected on the population's primary spring staging area in Nebraska, U.S.A., were used to resolve the genetic relationship among these subspecies. Phylogenetic analysis of 27 G. canadensis, by DNA sequencing of a 675 bp region of the mtDNA, supports the subspecies designations of G. c. canadensis and G. c. tabida. G. c. rowani individuals were intermediate with each of the other two subspecies. Genetic divergence ranged from 6.5 to 14.5% between G. c. canadensis and G. c. tabida, 0.5 to 6.6% within G. c. canadensis, and 0.1 to 6.0% within G. c. tabida. Sufficient DNA for analysis was obtained from shed feathers indicating a source of genetic material that does not require the capture or sacrifice of the birds. Other genetic markers and methods, including satellite telemetry, are required for obtaining detailed information on crane distributions as needed to establish effective management units for the MCP.     

中国动物园白鹤圈养种群统计学与遗传学分析

根据《圈养白鹤中国地区谱系簿2012》提供的数据,应用种群管理软件SPARKSv1.6和PMxv1.0对中国动物园白鹤圈养种群进行统计学和遗传学分析。结果显示该种群面临着许多困难,未知性别比例过高(截止到2012年10月31日,中国动物园白鹤圈养种群数量达到92只,其中雄性24只,雌性29只,未知性别39只)、年龄结构不合理(育龄个体数量充足,但幼龄个体数量仅有14只,约占现存种群的15.22%)、基因多样性丢失快(野外来源个体数量较多,达到58只,约占总数的63.04%,但是实际参与繁殖的奠基者仅有7只;该群体中某些奠基者的后代数量较多,种群平均亲缘关系值MK=0.15,从而导致现有种群只保留了野生个体85.25%的基因多样性)、种群数量增长乏力(2006～2012年种群的平均增长率λ=0.98)。因此,为了建立一个健康的白鹤圈养种群,应尽快开展性别鉴定工作,改善饲养环境条件,减少创伤引发的死亡,同时采用各种技术(如人工授精)增加潜在奠基者的繁殖机会,从而尽快扩大种群数量,并减少后代过多个体奠基者的繁殖机会。     

Food consumption and retention time in captive whooping cranes (Grus americana)

Food consumption, digesta retention time, and food preference were measured for captive whooping cranes fed pelleted diets. The basal commercial diet was compared to four mixtures containing 70% basal and 30% of one of four important winter foods for the whooping crane: blue crab (Callinectes sapidus), wolfberry fruit (Lycium carolinianum), live oak acorn (Quercus virginiana), or common Rangia clam (Rangia cuneata). Because captive birds would not eat whole foods, we were prevented from direct food preference tests. Food passed through the gut rapidly, with almost complete elimination within 7 hr. There was some indication that retention time was shorter for the low fiber and high ash and calcium clam diet. Cranes ate less wolfberry feed (g/day) than the other feeds, and all birds ate less wolfberry feed on the day it was first fed, compared to basal diet the previous day. Birds ate more low energy feed than high energy feed. Due to combined effects of low energy content, lower metabolizable energy coefficients, and reduced feed consumption, less energy was assimilated for study diets than basal diet. Apparent shorter retention times for some diets containing whooping crane foods may partly explain lower digestibilities and metabolizable energy of winter whooping crane foods compared to commercial crane diet. Zoo Biol 16:519–531, 1997. © 1997 Wiley-Liss, Inc.     

Mortality factors and diseases in free-ranging Eurasian cranes (Grus grus) in Germany

Detailed postmortem examinations were performed on 167 free-ranging Eurasian Cranes (Grus grus) from Germany, collected between September 1998 and December 2008 to evaluate causes of death and diseases. The most common causes of mortality were traumatic injuries (n=105, 62.9%) from collisions with power lines (n=39, 23.4%) and wire fences (n=12, 7.2%). A group of 28 Eurasian Cranes (16.8%) died from organophosphate intoxication. Predation by White-tailed Sea Eagles (Haliaeetus albicilla) and red foxes (Vulpes vulpes) occurred in four cases (2.4%). Pathologic changes due to infectious diseases were associated with Aspergillus spp. (n=7, 4.2%), endoparasites (n=7, 4.2%), avian poxvirus (n=6, 3.6%), Mycobacterium spp. (n=2, 1.2%), and adenovirus infection (n=1, 0.6%). A severe Strigea spp. infection (n=1, 0.6%) and a leiomyosarcoma (n=1, 0.6%) were newly recognized diseases in Eurasian Cranes in this study.     

Positional behavior of Siberian chipmunks (Tamias sibiricus) in captivity

Arboreal and semi-arboreal mammals have remarkably diverse positional behavior and associated morpho-functional adaptations related to the three-dimensional nature of their arboreal habitat. In this context, we investigated the positional behavior of captive Siberian chipmunks (Tamias sibiricus), small bodied semi-arboreal sciurids, in an aviary-type wire-mesh cage containing both terrestrial and arboreal supports. We sampled four adult individuals during a five-month period using focal animal sampling every 30 s. Results showed that animals preferred 8–10 cm horizontal supports and always avoided vertical supports. Locomotion occurred on both terrestrial and 8–10 cm arboreal supports whereas postural behavior occurred primarily on 8–10 cm arboreal supports. Quadrupedal walk dominated during locomotion, and occurred primarily on terrestrial horizontal supports, as is observed for other squirrels. The predominance of quadrupedal locomotion is consistent with the postcranial morphology of chipmunks. In contrast, clawed locomotion occurred on wire mesh and on >13 cm arboreal vertical supports. Finally, pronograde and orthograde sitting, both on 8–10 cm arboreal supports and on terrestrial supports, were the predominant postures, implying general predisposition to selection of stable postures on stable supports for food item manipulation and ingestion.     

Quantitative assessment of pair formation behavior in captive whooping cranes (Grus americana)

Instantaneous scan sampling for mean distance and synchronous action patterns and all-occurrence sampling for unison call, dance, strut, and hoover-up behaviors were conducted for five potential whooping crane pairs at Patuxent Environmental Science Center, Laurel, Maryland. Dance, strut, and hoover-up differed among pairs, as did total frequency of social behaviors. It was unclear whether or not total frequency of social behaviors during pair formation can be used as an index for potential breeding success. The relative importance of different action patterns should be used as indices of pair compatibility in captive whooping cranes. © 1995 Wiley-Liss, Inc.