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。     

四川美姑、汉源黑颈鹤迁徙停歇地环境调查

于2005年及2006年春季在云南大山包和贵州草海给8只黑颈鹤(Grus nigricollis)放置了卫星发射器,观察结果表明,其中6只黑颈鹤至少完成了一次完整的春季或秋季迁徙。黑颈鹤在四川省汉源停歇的乡镇包括:乌斯河镇、河南、坭美、梨园、宜东、三交坪和皇木;在美姑停歇的乡镇包括:柳洪、依果觉、农作、拉木阿觉、炳途、瓦古、峨曲古龙门和尼哈。2005年6月4~8日和2006年6月8~14日实地考察了汉源和美姑两县的黑颈鹤停歇地点。黑颈鹤在两县的停歇地点都在海拔1900m以上且人为活动稀少的区域,或为草甸覆盖的高山浑圆山头,或为高山缓坡的林间空旷草地。     

Tetrameres (Tetrameres) grusi (Shumakovich, 1946) (Nematoda: Tetrameridae) in Eurasian cranes (Grus grus) in central Iran

The proventriculi of 11 Eurasian cranes (Grus grus) from central Iran were examined for the existence of parasitic helminths. Preliminary reports suggested that the death of these birds was related to untimely cold weather. Nine proventriculi (82%) were heavily infected by the nematode Tetrameres grusi. Glandular structure of the infected proventriculi was replaced by epithelial atrophy but significant inflammatory reactions were not observed in any of the infected organs. In serious infections, the nematode produced vast structural and functional changes, causing organ dysfunction and glandular necrosis. The coincidence of heavy helminth infection at times of environmental stress may lead to debilitation, wasting, and perhaps mortality in migratory cranes.     

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).     

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.     

Migration routes and stopover sites of Black-necked Cranes determined by satellite tracking

ABSTRACT.   Because their breeding and wintering areas are in remote locations, little is known about the biology of Black-necked Cranes ( Grus nigricollis ), including their migratory behavior. Using satellite telemetry, we monitored the migration of Black-necked Cranes ( N = 6) in China to determine migration routes and the location of stopover sites. From 2005 to 2007, four cranes were tracked during two spring migrations and one fall migration, one was tracked during one spring and one fall migration, and one was tracked during one spring migration. On average, the cranes made seven flights over a 5-d period to migrate 651 km to breeding areas in the spring. In the fall, birds averaged six flights in 5 d to migrate 694 km. The routes traveled by cranes during spring and autumn migration were similar. Both the migration distances and duration of migration are the shortest reported for any crane species to date. Most stopover sites were in areas along rivers and close to wetlands in the Daliang Mountains and the Ruoergai Plateau. Conservation measures are needed to reduce habitat loss (wetland and pasture) in the Daliang Mountains and establish a reserve for stopover sites in the Ruoergai marshes, such as Longriba and Bai River in Hongyuan County.     

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.     

Advances in ecological studies of epiphytes using canopy cranes

Forest canopies are one of the most species-rich habitats, but among the least explored in the biosphere. They play a crucial role in the process of material and energy exchange between the forest and atmosphere. Individual ecosystem members (e.g., epiphytes) and the ecological function of canopies have been given insufficient attention because of inaccessibility. Canopy cranes have been successfully used to guarantee non-destructive and reiterated sampling of epiphytes, thus offering a top-down perspective of the entire canopy. These cranes have become the symbol of canopy research and enable epiphyte research. Globally, western developed countries have conducted many studies of diversity and spatial distributions of epiphytes using canopy cranes, thus accumulating an abundance of valuable results. This review summarizes the structure, development history, and distribution of canopy cranes as well as general information about international canopy research organizations. Ecological studies of epiphytes performed around the world using these canopy cranes are also reviewed. Additionally, the development of canopy ecology and the construction of canopy cranes in China are introduced briefly. In analyzing current research trends in ecological studies of epiphytes in China and globally, the following aspects were considered: biodiversity, spatial patterns and maintenance mechanisms, ecological adaptations of epiphytes, their relationship with canopy animals, and their responses to climate change.     

基于林冠塔吊的附生植物生态学研究进展

林冠是生物圈中物种最丰富却最鲜为人知的生境之一。它在森林与大气的物质、能量交换过程中发挥着至关重要的作用。但因林冠调查技术的限制, 林冠及生存在其中的附生植物在生态系统中的功能尚未得到足够的重视。塔吊在三维空间中作业具有“全方位、高精度、非破坏、可重复”的特征。林冠塔吊已成为当前林冠学研究的标志, 并为林冠附生植物研究提供了契机。国际上, 欧美国家利用塔吊技术对林冠层附生植物多样性与空间分布等进行了大量的研究, 取得了丰硕的成果。该文介绍了塔吊的构造、林冠塔吊建设历史和站点分布及国际林冠研究组织等概况, 并对依托塔吊开展的附生植物研究进展进行了评述。此外, 还简要介绍了我国塔吊建设与林冠生态学发展情况。在系统分析国内外附生植物研究现状基础上, 从附生植物多样性、附生植物空间格局与维持机制、生态适应性、与林冠动物的关系以及附生植物对气候变化的响应等5个方面对今后基于林冠塔吊开展附生植物研究进行了展望。     

Grey Crowned Crane threat assessment around the wetlands of eastern Uganda

The Grey Crowned Crane Balearica regulorum was uplisted to globally Endangered in 2012. There is urgent need to determine the threats they face at local levels for their conservation. I conducted formal point-count surveys around the wetlands of eastern Uganda and observed no cranes. Groups of cranes were encountered when following directions from local inhabitants. Results from a questionnaire survey suggested that cranes make use of most of the wetlands in the region, and that the birds occur in small flocks averaging 6–8 individuals. Wetland loss through farming was reported to be the main threat, but I also documented poisoning, roost disturbance, and the collection of eggs and chicks. Rigorous conservation and education programs are needed to ensure the long-term survival of cranes and storks in this region.     

对白枕鹤领域的初步研究

1986-1988年的3-5月间,在黑龙江省林甸县对白枕鹤的领域进行了研究。三年中,对8个巢的领域研究结果表明,白枕鹤多年连续利用同一领域,占据的最大领域面积为10.7平方公里,平均不超过7.0平方公里,并随繁殖过程而缩小,至雏期活动和防御范围只有1.5平方公里左右。多数白枕鹤的领域内包括一片耕地为固定觅食区,但小于无耕地的领域面积。     

Spatially Explicit Assessment of Sandhill Crane Exposure to Potential Transmission Line Collision Risk

Infrastructure development can affect avian populations through direct collision mortality. Estimating the exposure of local bird populations to the risk of direct mortality from infrastructure development requires site- and species-specific data, which managers may find difficult to obtain at the scale over which management decisions are made. We quantify the potential exposure of sandhill cranes (Antigone canadensis) to collision with horizontal structures (e.g., transmission lines) within vital wintering grounds of the Middle Rio Grande Valley (MRGV), New Mexico, USA, 2014–2020. Limited maneuverability and visual acuity make sandhill cranes vulnerable to collisions with infrastructure bisecting their flight paths. We used data from 81 global positioning system (GPS)-tagged cranes to estimate the spatially explicit flight height distribution along the MRGV, the passage rate across hypothetical transmission lines, and the resulting exposure rate (exposed passes/crane/day). The exposure rate ranged from 0–0.28 exposed passes/crane/day (median = 0.015) assuming an exposure zone of 7–60 m above ground level, and identified hotspots of potential exposure within the MRGV. Mapped exposure rates can assist in the siting of proposed high-voltage transmission lines, or other infrastructure, to limit effects on sandhill cranes and other avian species at risk of collision. Our approach can be replicated and applied in similar situations where birds are exposed to possible collision with power lines. © 2021 The Authors. The Journal of Wildlife Management published by Wiley Periodicals LLC on behalf of The Wildlife Society.     

MORTALITY OF RINGED YELLOW-BILLED DUCK

Davenport, L.B.Jr. &; Urban, E.K. 2000. Time budgets for Captive Wattled Cranes Bugeranus carunculatus. Ostrich 71 (1 &; 2):136-138.

Time budgets for six pairs of captive Wattled Cranes were recorded in the years 1989–1991 at St. Catherine's Island, Georgia, U.S.A., using instantaneous sampling at 30 s intervals. Data were obtained to cover one complete day, from earliest light to obscuring dusk, for each month of the year. When not nesting, these cranes spent slightly more than half of their time standing, preening, and/or walking, and most of the rest of their time eating, searching, or sleeping. When nesting, both sexes engaged equally in nest building, egg turning, and arranging nest material with the female devoting 45% of her time to incubating, the male about 40%. Males spent about 13% and females 8% of their time during the nesting period confronting neighboring cranes or other large species such as Great Blue Herons. It is concluded that instantaneous sampling at 30 s intervals with one person watching and another recording one or two individual cranes is a reasonably satisfactory method for recording time budgets in captive and probably wild populations of Wattled Cranes.     

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.     

Population and Harvest Dynamics of Midcontinent Sandhill Cranes

Sandhill cranes (Antigone canadensis) inhabiting the midcontinent of North America have been hunted since the 1960s under management goals of maintaining abundance, retaining geographic distribution, and maximizing sustainable harvest. Some biologists have raised concerns regarding harvest sustainability because sandhill cranes have lower reproductive rates than other game birds. We summarized demographic information in an age-structured matrix model to better understand population dynamics and harvest. Population indices and recovered harvest since the early 1980s suggest midcontinent sandhill cranes have experienced an average long-term annual growth of 0.9%; meanwhile, harvest has increased 1.8% annually. Adult survival and recruitment rates estimated from field data required modest adjustments (1–3%) so that model-derived growth rates matched growth estimated from a long-term survey (0.887 adult survival and 0.199 females/breeding female). Considering 0.9% long-term annual growth, sandhill cranes could be harvested at a rate of 6.6% if harvest was additive to natural mortality (assumed to be 0.05) or 11.3% if harvest mortality compensated for natural mortality. Life-history characteristics for long-lived organisms and demographic evidence suggested that hunter harvest was primarily additive. Differential harvest rates of segments of sandhill cranes in the midcontinent population derived from differential exposure to hunting suggested potentially unsustainable harvest for greater sandhill cranes (A. c. tabida) from 2 breeding segments. Overall, demographic evidence suggests that the harvest of sandhill cranes in the midcontinent population has been managed sustainably. Monitoring activities that reduce nuisance variation and estimate vital and harvest rates by subspecies would support continued management of sandhill cranes that are of interest to hunters and bird watchers. Published 2020. This article is a U.S. Government work and is in the public domain in the USA.     

鄱阳湖周边稻田对白鹤的承载力

鄱阳湖是世界重要的候鸟越冬地,承载了全球约98%的白鹤(Leucogeranus leucogeranus)。然而,近年来鄱阳湖沉水植被退化严重,白鹤的传统食物苦草(Vallisneria spp.)冬芽丰富度急剧减少。食物短缺导致白鹤的觅食生境由自然湿地的浅水生境转移至稻田、藕塘等人工生境,稻田在白鹤保护中发挥的作用日益突出。了解鄱阳湖周边稻田对白鹤的承载力可为白鹤的保护和管理提供科学依据。为此,调查了鄱阳湖周边稻田散落稻谷的生物量,测量了稻谷的营养成分,并利用遥感影像对鄱阳湖周边10 km范围内稻田的总面积进行估算,从而得出鄱阳湖周边稻田散落稻谷能提供的总能量。然后,计算稻田中以稻谷为主要食物的6种鸟类的日能量消耗,用以表示日能量摄入。最后,依据稻田能提供的总能量、鸟类的日能量摄入、鸟类的越冬时长、以及各种鸟类的数量占比,计算得出鄱阳湖周边稻田能承载的白鹤数量。结果表明,鄱阳湖周边稻田散落稻谷的生物量为6.494 g/m²,环鄱阳湖周边10 km范围内稻田的总面积为1984.46 km²,这些稻田能承载的鸟类总数量为140860只,其中能承载的白鹤数量为10775只,超过了全球白鹤的总数量(3500-4000只)。因此,鄱阳湖周边稻田能为白鹤等鸟类提供丰富的食物资源。     

Cohort study of peanut and tree nut sensitisation by age of 4 years.

OBJECTIVE: To determine the prevalence of sensitisation to peanuts and tree nuts in all children born during one year in one geographical area. DESIGN: Birth cohort study with structured review at ages 1, 2, and 4 years. SETTING: All children born on the Isle of Wight between January 1989 and February 1990. SUBJECTS: Of 1456 children originally included, 1218 were reviewed at age 4 years. Of these, 1981 had skin prick tests. MAIN OUTCOME MEASURES: Positive skin test results, clinical atopic disease, and risk factors for the development of atopy. RESULTS: 15 of 1218 (1.2%) children were sensitised to peanuts or tree nuts (13 to peanuts). Six had had allergic reactions to peanuts (0.5% of the population), one to hazelnuts, and one to cashew nuts; three had had anaphylactic reactions. Seven children had positive skin test results or detectable IgE to peanuts without clinical symptoms. Two children who reacted to peanut in infancy had lost their sensitivity by 4 years. Family history of atopy, allergy to egg (odds ratio 9.9, 95% confidence interval 2.1 to 47.9, and eczema (7.3, 2.1 to 26.1) were important predictors for peanut allergy. CONCLUSIONS: IgE mediated allergy to peanuts is common in early childhood. In many the allergy persists but a minority may develop tolerance.     

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.     

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.     

Geographic distribution of the mid-continent population of sandhill cranes and related management applications

The Mid-continent Population (MCP) of sandhill cranes (Grus canadensis) is widely hunted in North America and is separated into the Gulf Coast Subpopulation and Western Subpopulation for management purposes. Effective harvest management of the MCP requires detailed knowledge of breeding distribution of subspecies and subpopulations, chronology of their use of fall staging areas and wintering grounds, and exposure to and harvest from hunting. To address these information needs, we tagged 153 sandhill cranes with Platform Transmitting Terminals (PTTs) during 22 February–12 April 1998–2003 in the Central and North Platte River valleys of south-central Nebraska. We monitored PTT-tagged sandhill cranes, hereafter tagged cranes, from their arrival to departure from breeding grounds, during their fall migration, and throughout winter using the Argos satellite tracking system. The tracking effort yielded 74,041 useable locations over 49,350 tag days; median duration of tracking of individual cranes was 352 days and 73 cranes were tracked >12 months. Genetic sequencing of mitochondrial DNA (mtDNA) from blood samples taken from each of our random sample of tagged cranes indicated 64% were G. c. canadensis and 34% were Grus canadensis tabida. Tagged cranes during the breeding season settled in northern temperate, subarctic, and arctic North America (U.S. [23%, n = 35], Canada [57%, n = 87]) and arctic regions of northeast Asia (Russia [20%, n = 31]). Distribution of tagged cranes by breeding affiliation was as follows: Western Alaska–Siberia (WA–S, 42 ± 4% [SE]), northern Canada–Nunavut (NC–N, 21 ± 4%), west-central Canada–Alaska (WC–A, 23 ± 4%) and East-central Canada–Minnesota (EC–M, 14 ± 3%). All tagged cranes returned to the same breeding affiliation used during the previous year with a median distance of 1.60 km (range: 0.08–7.7 km, n = 53) separating sites used in year 1 and year 2. Fall staging occurred primarily in central and western Saskatchewan (69%), North Dakota (16%), southwestern Manitoba (10%), and northwestern Minnesota (3%). Space-use sharing indices showed that except for NC–N and WC–A birds, probability of finding a crane from one breeding affiliation within the home range of another breeding affiliation was low during fall staging. Tagged cranes from WC–A and EC–M breeding affiliations, on average, spent 25 and 20 days, respectively, longer on fall staging areas in the northern plains than did WA–S and NC–N birds. Cranes in the NC–N, WA–S, and WC–A affiliations spent 99%, 74%, and 64%, respectively, of winter in western Texas in Hunting Zone A; EC–M cranes spent 83% of winter along the Texas Gulf Coast in Hunting Zone C. Tagged cranes that settled within the breeding range of the Gulf Coast Subpopulation spent 28% and 42% of fall staging and winter within the range of the Western Subpopulation, indicating sufficient exchange of birds to potentially limit effectiveness of MCP harvest management. Harvests of EC–M and WC–A cranes during 1998–2003 were disproportionately high to their estimated numbers in the MCP, suggesting more conservative harvest strategies may be required for these subpopulations in the future, and for sandhill cranes to occupy major parts of their historical breeding range in the Prairie Pothole Region. Exceptionally high philopatry of MCP cranes of all 4 subpopulations to breeding sites coupled with strong linkages between crane breeding distribution, and fall staging areas and wintering grounds, provide managers guidance for targeting MCP crane harvest to meet management goals. Sufficient temporal or spatial separation exists among the 4 subpopulations on fall staging areas and wintering grounds to allow harvest to be targeted at the subpopulation level in all states and provinces (and most hunting zones within states and provinces) when conditions warrant. Knowledge gained from our study provides decision-makers in the United States, Canada, Mexico, and Russia with improved guidance for developing sound harvest regulations, focusing conservation efforts, and generating collaborative efforts among these nations on sandhill crane research and management to meet mutually important goals. © 2011 The Wildlife Society.