Levels of fecal corticosterone in sandhill cranes during a human-led migration

Fourteen captive-reared greater sandhill cranes (Grus canadensis tabida) were conditioned to follow ultralight aircraft to promote migration between Wisconsin and Florida (USA) after release. Fecal samples were collected throughout the training period in Wisconsin and during a l977-km human-led migration to Florida to determine fecal corticosterone (FC) concentrations by radioimmunnoassay. The mean (+/-SE) FC concentration during the training period was 109.5 +/- 7.5 ng/g and was representative of baseline levels recorded previously from sandhill cranes. Fecal corticosterone concentrations increased in early migration compared to concentrations I mo prior to departure (P < 0.01) but were not different from baseline concentrations at tile end of the 6-wk migration period. The variability of FC concentrations in individual samples was greater throughout the migration than the training period. Increases in FC during migration were modest and generally consistent with normal corticosterone elevations observed in migrating birds.     

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.     

Coccidia of whooping cranes

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.     

Persistence of inclusion body disease of cranes virus

Persistence of inclusion body disease of cranes virus (IBDCV) was determined by monitoring virus shedding, serum antibody and in vitro cultivation of trigeminal ganglia from cranes. Samples were collected from captive cranes surviving the outbreak in 1978 and from cranes inoculated with the virus. Tissues and fluids from eggs of cranes that survived the outbreak were also tested for virus. Latent IBDCV was found in the trigeminal ganglion of one crane that was exposed to the virus in 1978. Spontaneous or induced (cyclophosphamide and dexamethasone) reactivation of viral shedding was not detected in any cranes tested. Five of six experimentally inoculated cranes died with lesions of an inclusion body disease, but virus was isolated from only three of them. One crane shed detectable levels of IBDCV prior to death. The surviving crane developed a transient antibody response without evidence of viral shedding, after five exposures to the virus. A latent infection was not detected in this crane. Serum antibody titers of cranes that survived the outbreak declined from 1980-1982. No virus was isolated from the eggs. Although IBDCV is capable of persisting in a latent form in the trigeminal ganglia of cranes, the low frequency of viral shedding suggests that this virus may be only a sporadic problem.     

基于极坐标定位的丹顶鹤多尺度越冬生境选择研究——以江苏盐城自然保护区为例

丹顶鹤作为湿地环境的指示物种,其种群数量逐年下降引起了野生动物保护工作者的广泛关注。近年来,随着研究的深入,鸟类生境选择具有多尺度特征的观点逐渐成为研究者的共识。江苏盐城自然保护区是丹顶鹤大陆西线种群最重要的越冬栖息地,选择该区域进行多尺度越冬生境选择研究对于丹顶鹤保护具有重要的现实意义。基于遥感影像和丹顶鹤越冬分布的调查,本文用极坐标的方法在GIS软件中对丹顶鹤分布定位进行制图。借助Arc GIS 10.2和fragstats 4.2软件,从点缓冲、景观和区域3个尺度系统分析丹顶鹤越冬生境多尺度利用特征。在点缓冲尺度上,通过缓冲分析和叠置分析描述丹顶鹤生境利用的强度,发现丹顶鹤连续利用生境和经常利用生境的植被类型是碱蓬,偶尔在芦苇中活动,偏好生境区植被覆盖度在30%以下,植被高度在60 cm以下。在景观尺度上,丹顶鹤偏好程度较高的前三类生境为芦苇沼泽、碱蓬沼泽、明水,对互花米草沼泽具有负向选择。在区域尺度上,受道路和土地利用干扰影响,丹顶鹤主要分布于保护区核心区的低干扰区域;除了干扰之外还与生境面积、生境破碎程度密切相关。综合三个尺度,研究得出丹顶鹤生境选择具有明显的多尺度利用特征,丹顶鹤保护需要考虑多尺度生境保护问题。     

Pulmonary lesions in disseminated visceral coccidiosis of sandhill and whooping cranes

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.     

Location and agricultural practices influence spring use of harvested cornfields by cranes and geese in Nebraska

Millions of ducks, geese, and sandhill cranes (Grus canadensis; hereafter cranes) stop in the Central Platte River Valley (CPRV) of Nebraska to store nutrients for migration and reproduction by consuming corn remaining in fields after harvest. We examined factors that influence use of cornfields by cranes and geese (all mid-continent species combined; e.g., Anser, Chen, and Branta spp.) because it is a key step to efficient conservation planning aimed at ensuring that adequate food resources are available to migratory birds stopping in the CPRV. Distance to night-time roost site, segment of the CPRV (west to east), and agricultural practices (post-harvest treatment of cornfields: idle, grazed, mulched, mulched and grazed, and tilled) were the most important and influential variables in our models for geese and cranes. Probability of cornfield use by geese and cranes decreased with increasing distance from the closest potential roosting site. The use of cornfields by geese increased with the density of corn present there during the early migration period, but field use by cranes appeared not to be influenced by early migration corn density. However, probability of cornfield use by cranes did increase with the amount of wet grassland habitat within 4.8 km of the field. Geese were most likely to use fields that were tilled and least likely to use fields that were mulched and grazed. Cranes were most likely to use fields that were mulched and least likely to use fields that were tilled, but grazing appeared not to influence the likelihood of field use by cranes. Geese were more likely to use cornfields in western segments of the CPRV, but cranes were more likely to use cornfields in eastern segments. Our data suggest that managers could favor crane use of fields and reduce direct competition with geese by reducing fall and spring tilling and increasing mulching. Moreover, crane conservation efforts would be most beneficial if they were focused in the eastern portions of the CPRV and in fields as close as possible to both known roosting and large amounts of wet grassland habitats. © 2011 The Wildlife Society.     

Fusarium mycotoxins from peanuts suspected as a cause of sandhill crane mortality

An estimated 9,500 sandhill cranes (Grus canadensis) died in Gaines County, Texas and Roosevelt County, New Mexico between 1982 and 1987. The predominant clinical sign observed in sick cranes was their inability to hold their heads erect, both while standing and flying. Multiple muscle hemorrhages and submandibular edema were the most common lesions seen at necropsy. Mycotoxins produced by Fusarium sp. growing during cold, wet weather on peanuts left in the field after harvest, the predominant foods of the dead cranes at the time of these mortality events, were identified as the most likely cause of this mortality. Rendering moldy peanuts inaccessible to the cranes by conventional tillage resulted in reduced crane mortality in these areas.     

云贵高原黑颈鹤的种群数量和分布

云贵高原有黑颈鹤的两个越冬区：(1）云南西部;(2)云南东北部和贵州西北部。这两个地区的黑颈鹤数量占全球种群的1／4至1／3。国际鹤类基金会与云南省林业厅于2001／2002年冬季在云贵高原联合对黑颈鹤进行了一次同步计数,本次调查覆盖了17个已知或潜在的黑颈鹤越冬地点,其中15个地点有黑颈鹤分布。在2002年1月18日和19日,分别记录到3261和3182只黑颈鹤。本调查还统计了灰鹤、斑头雁和赤麻鸭,数量分别为：灰鹤804和1158只;斑头雁1759和2978只;赤麻鸭3442和5444只。与1991／1992年冬季进行的调查结果相比,黑颈鹤在这一地区的数量增加了90％以上。     

黑颈鹤越冬生态初步研究

黑颈鹤为我国特产珍稀动物,作者于1975和1978至1984年间,对它的越冬生态进行了观察。观察得知,黑颈鹤每年10月中、下旬迁来草海,翌年8月中下旬离去,越冬期为5个月左右。越冬期,有3种不同的集群形式,即家族群、同种集群和混种集群。主要食物为植物。黑颈鹤在草海越冬的数量,已由1975年的35只,增加到1984年的305只。黑颈鹤除在草海越冬外,还发现于威宁东南的普安县,是迄今所知在我国分布最南和最东的纪录。     

无人机调查白鹤种群数量和越冬分布

白鹤(Leucogeranus Leucogeranus)是国家Ⅰ级重点保护野生动物,唯一一种极度濒危(CR)鹤类,分布和种群数量是评估其濒危程度的重要参数。无人机调查作为目前生态学研究的一个重要调查方法,为查明白鹤的越冬分布、种群数量及幼鸟比例,于2022年1月使用地面监测结合无人机调查的方法在江西、山东、安徽、湖南、湖北等地的湖泊和农田中开展越冬白鹤调查。野外调查共记录白鹤5607只,网络信息检索在调查区域外的8个地点记录白鹤9只,合计记录越冬白鹤5616只。其中江西鄱阳湖记录到越冬白鹤4813只,占总数的85.7%,主要分布在康山垦殖场、五星垦殖场和成新垦殖场;山东黄河三角洲记录到越冬白鹤625只,占总数的11.1%。安徽、湖南、湖北分别记录到越冬白鹤34,63和72只。对部分群体的白鹤幼鸟数量进行统计,4680只白鹤中,记录到幼鸟674只,幼鸟比例为14.4%,其中湖南越冬白鹤幼鸟比例最高,达28.6%,山东越冬白鹤幼鸟比例最低,为11.5%。调查刷新了白鹤种群数量,证实了山东黄河三角洲是目前除江西鄱阳湖外最重要的白鹤越冬地,缓解了白鹤越冬期过度集中的压力。基于本研究结果,我们...     

Changes in Agriculture and Abundance of Snow Geese Affect Carrying Capacity of Sandhill Cranes in Nebraska

ABSTRACT The central Platte River valley (CPRV) in Nebraska, USA, is a key spring-staging area for approximately 80% of the midcontinent population of sandhill cranes (Grus canadensis; hereafter cranes). Evidence that staging cranes acquired less lipid reserves during the 1990s compared to the late 1970s and increases in use of the CPRV by snow geese (Chen caerulescens) prompted us to investigate availability of waste corn and quantify spatial and temporal patterns of crane and waterfowl use of the region. We developed a predictive model to assess impacts of changes in availability of corn and snow goose abundance under past, present, and potential future conditions. Over a hypothetical 60-day staging period, predicted energy demand of cranes and waterfowl increased 87% between the late 1970s and 1998–2007, primarily because peak abundances of snow geese increased by 650,000 and cranes by 110,000. Compared to spring 1979, corn available when cranes arrived was 20% less in 1998 and 68% less in 1999; consequently, the area of cornfields required to meet crane needs increased from 14,464 ha in 1979 to 32,751 ha in 1998 and 90,559 ha in 1999. Using a pooled estimate of 88 kg/ha from springs 1998–1999 and 2005–2007, the area of cornfields needed to supply food requirements of cranes and waterfowl increased to 65,587 ha and was greatest in the eastern region of the CPRV, where an estimated 54% of cranes, 47% of Canada geese (Branta canadensis), 45% of greater white-fronted geese (Anser albifrons), and 46% of snow geese occurred during ground surveys. We estimated that a future reduction of 25% in available corn or cornfields would increase daily foraging flight distances of cranes by 27–38%. Crane use and ability of cranes to store lipid reserves in the CPRV could be reduced substantially if flight distance required to locate adequate corn exceeded a physiological maximum distance cranes could fly in search of food. Options to increase carrying capacity for cranes include increasing accessibility of cornfields by restoring degraded river channels to disperse roosting cranes and increasing wetland availability in the Rainwater Basin to attract snow geese using the CPRV.     

云南省纳帕海自然保护区越冬黑颈鹤的集群特征

2004年10月-2005年5月,在云南纳帕海自然保护区采用定点扫描法对越冬黑颈鹤(Grus nigricollis)的集群类犁和集群大小进行了观察.结果表明黑颈鹤夜间集群夜栖,形成较大的夜栖群,平均群体大小为67.9只(16-157,n=17):按照有无灰鹤加入,又将其分为同种集群和混种集群两种类型,其中同种集群的黑颈鹤数量占整个越冬种群的65.3%.在白昼,黑颈鹤以家庭鹤、集群鹤及特殊群体3种类型活动,家庭鹤和集群鹤的平均大小分别为2.7只(2-4,n=145)和16.1只(3-65,n=1017).黑颈鹤的集群大小并不稳定,在日内和月份间均有明显变化(P=0.000＜0.05).存越冬期,最大集群形成于12月,其次为11月和1月;在日内,早上8时集群最大,随后减小并保持相对稳定,18时黑颈鹤开始向夜栖地靠拢,使得集群再次开始增大.随后观察中还发现,黑颈鹤的家庭解体过程开始于3月底,当幼鹤被成鹤驱逐离群后,逐渐加入集群鹤活动,从而使得家庭鹤和集群鹤的大小和组成发生改变.黑颈鹤的集群大小和组成受自身状况、种内关系、天气、食物等多种因素的共同影响,随时间和季节变动而发生变化,是对自身、种群和环境条件变化的综合反映.     

Use of surrogate parental models and age periods in a successful release of hand-reared sandhill cranes

Ten sandhill crane chicks were reared in isolation from humans to prepare them for an experimental wild release. They were imprinted on realistic models using crane brooding calls and were fed by crane-like puppets. Six of the chicks were simultaneously imprinted on a human in a crane costume. The other four chicks were introduced to this surrogate parent at 5–7 days of age. The chicks were fed natural foods by the parent at two wild sites, one of which, the release site, was a staging area for migratory cranes. Observations were made on their behavioral development, including the time spent close to the model or costumed parent and the percentage of time spent foraging. The chicks spent the initial month close to the surrogate parent but moved away more to forage during the second month. The chicks regressed to again spend a great deal of time near the parent during the third and fourth months. They were released during this regressive period by removing the surrogate parent. All five of the released chicks showed increased interest in wild cranes within days of the release and formed a continuous association with wild cranes within 30 days. Four of the five were relocated by telemetry the following spring back in Wisconsin. These young juvenile cranes were excellent candidates for release due to their adaptable nature and their level of social development. The artificial stimuli of the surrogate parent helped the chicks to generalize their attachment to wild cranes. Once with wild cranes they quickly learned additional survival skills.     

Allozyme evidence for crane systematics and polymorphisms within populations of Sandhill, Sarus, Siberian, and whooping cranes.

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.     

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。     

Capture of sandhill cranes using alpha-chloralose

From 1990-2001, we made 188 successful captures of 166 different greater sandhill cranes (Grus canadensis tabida) through experimental use of alpha-chloralose (AC). Most captures took place during September (72.3%; n = 136), followed by August (14.9%; n = 28), and October (12.8%; n = 24). Territorial pairs were captured more successfully than family groups. Overall morbidity (6.4%) and mortality (4.3%) were lower than most other capture techniques for sandhill cranes. Exertional myopathy (EM) was the most common complication observed using AC (3.7%). Sedation level (chi5(2) = 25.9, P < 0.01) and month of capture (chi2(2) = 12.3, P < 0.01) were both associated with the presence of EM in cranes captured with AC. A logistic regression model suggests lighter sedation and the months of August and October are potential risk factors for EM in sandhill cranes captured with AC in Wisconsin (USA).     

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.     

Pb and Cd Bioaccumulations in the Habitat and Preys of Red-Crowned Cranes (Grus japonensis) in Zhalong Wetland, Northeastern China

Pb and Cd concentrations in the habitat and preys of the red-crowned crane (i.e., reed rhizomes and three typical aquatic animal families (Perccottus glehni Dybowski, Carassius auratus Linnaeus, and Viviparidae)) were analyzed to examine the impact of these hazards on red-crowned cranes in northeastern China. Results indicated that Pb and Cd concentrations in the preys of the red-crowned cranes were elevated via food chain. Most of the detected Pb and Cd contents in the sediments were above the natural background level, ranging from 9.85 to 129.72 ppm and 1.23 to 10.63 ppm (dry weight), respectively. Cd geo-accumulation index at all sites were larger than 3, even reached 5.22, suggesting serious pollution in this region. Three common water animal families were detected to contain heavy metals, following the order of increasing concentrations: primary consumers (i.e., Viviparidae and Carassius auratus Linnaeus)?<?secondary consumers (i.e., Perccottus glehni Dybowski). Pb and Cd concentrations in the buffer zone are significantly higher than in the core area and being elevated in the food chain. The molten feathers of the red-crowned cranes showed the highest toxic metal concentrations of Pb (2.09 to 5.81 ppm) and Cd (1.42 to 3.06 ppm) compared with the feces produced by cranes and residual eggshell left by water fowls. Exceptionally high Pb and Cd concentrations in the cranes and their preys were thought to be associated with their habitat.     

崇明东滩白头鹤的越冬生态

对崇明东滩白头鹤（Grus monacha)的越冬生态进行了研究。白头鹤在崇明东滩越冬期140－150d。越冬期主要食物为海三棱Biao草（Scirpus mariqueter)的地下球茎,海三棱Biao草和Biao草（S.triqueter)的根茎。受气候和季节的影响,越冬后期比前期的日活动时间增加1h。潮汐节律影响越冬白头鹤行为活动的时间分配,觅食地的选择以及集群大小。滩涂的快速围垦和滩涂植被的演替对白头鹤的越冬栖息地造成严重的影响。