鄱阳湖稻田生境中越冬灰鹤行为模式及其影响因素

2018年10月—2019年3月,采用焦点动物法研究了鄱阳湖区稻田生境中灰鹤(Grus grus)越冬期的行为模式及其影响因素。结果表明:越冬期灰鹤的主要行为是觅食(77.45%)、警戒(11.17%)和修整(7.82%);行为模式以取食-警戒-取食或取食-修整-取食为主;幼鹤取食行为的时间分配和持续时间均极显著高于成鹤(P0.01),推测幼鹤取食效率低,单次取食持续时间和总时间较长;成鹤警戒行为(P0.01)极显著高于幼鹤,成、幼鹤警戒行为的持续时间无显著差异,取食间隔的警戒频次和时间分配均显著高于幼鹤(P0.05),说明成鹤是通过增加警戒次数来确保幼鹤的安全;取食行为的持续时间和时间分配在整个越冬期均显著升高,取食间隔期间的行走行为也逐渐上升,这与食物资源的可获得性有关;建议适当降低家鸭放牧等人类活动,减少灰鹤越冬期的取食难度;灰鹤不同家庭群的行走行为和取食间隔的行走行为均有显著性差异,推测与各家庭群占有的食物资源质量相关;行为节律上,灰鹤各时段取食行为占总行为的比例均较高,在10:00—10:59、12:00—12:59和16:00—16:59出现取食小高峰;警戒行为保持在一个稳定水平,修整行为高峰出现在取食行为高峰之后,这是因为灰鹤保持取食行为积累疲劳后进行修整;成鹤的取食行为节律性较幼鹤明显,幼鹤的取食行为曲线随机性强,这与幼鹤取食经验不足有关;幼鹤警戒行为的高峰出现在成鹤警戒的低谷,推测与保持整个家庭群较高的总体警戒水平有关。     

鄱阳湖围垦区藕塘越冬白鹤的时间分配与行为节律

2016年12月—2017年3月,采用瞬时扫描法研究了鄱阳湖围垦区藕塘生境中白鹤Grus leucogeranus越冬期的行为,共扫描2560次,23219只次,包括18031只次成鹤和5188只次幼鹤。结果表明,觅食(41.78%)、警戒(25.02%)、修整(15.00%)和休息(10.84%)是白鹤越冬期的主要行为。与自然生境相比,藕塘生境中白鹤主要采取多休息和修整的策略来节省能量支出。成鹤的觅食行为(35.29%)显著低于幼鹤(62.42%)(F_(1,12)=45.977,P0.01),警戒行为(28.66%)则显著高于幼鹤(10.26%)(F_(1,12)=38.975,P0.01)。家庭群成鹤觅食行为(43.96%)极显著高于非家庭群成鹤(27.04%)(F_(1,12)=60.169,P0.01)。家庭群成鹤需要喂食幼鹤,它们花费更多的时间觅食弥补能量的消耗。行为节律上,白鹤各时段觅食行为占总行为的比例均较高,11:00—11:59出现明显高峰,占总行为的48.64%。警戒行为无明显的低谷和高峰。成鹤在各时段的觅食行为比例均明显低于幼鹤,成鹤和幼鹤的觅食曲线变化趋势相似,即觅食比例的升高和降低比较同步。成鹤在各时段的警戒行为和修整行为比例均明显高于幼鹤,成幼鹤的休息行为比例在各时段差别不大,均在14:00—14:59有个明显的高峰。家庭群成鹤的觅食行为比例几乎在各时段均明显高于非家庭群,家庭群成鹤的修整行为和休息行为在大部分时段均低于非家庭群成鹤。因此家庭群成鹤采取多取食,少休息和修整的策略提高自身的适合度,同时保证对后代的抚育。     

年龄、集群、生境及天气对鄱阳湖白鹤越冬期日间行为模式的影响

于2012年1—3月和2012年12—2013年3月,采用瞬时扫描法研究了鄱阳湖国家级自然保护区越冬白鹤(Grusleucogeranus)的昼间时间分配模式和日活动节律,分析了年龄、集群大小、生境类型和天气对白鹤越冬行为的影响。结果表明,白鹤越冬期的主要行为有觅食、警戒、理羽、游走、休息和争斗。其中,觅食是鄱阳湖越冬白鹤主要行为,占其昼间活动时间的82.94%;警戒占11.94%,理羽占3.52%,游走占1.88%,休息占0.15%,争斗占0.02%。白鹤在越冬期间的觅食、游走、休息和争斗行为存在明显的昼间节律性,其中游走、觅食和争斗行为在每天的上午和下午各存在1个高峰,休息行为在中午出现一个高峰;警戒和理羽行为则没有显著的昼间节律变化。年龄、集群大小、天气和生境对白鹤的越冬行为具有显著的影响:幼鹤取食的时间显著多于成鹤,而警戒时间则显著的小于成鹤;与家庭群中的个体相比,集体群中的个体取食和争斗时间显著增加,警戒时间显著减少;在天气晴朗时,白鹤的警戒时间显著大于阴天的警戒时间,取食时间则显著少于阴天时白鹤的取食时间;白鹤在大风天气显著增加理羽行为;在有雾的天气会显著增加取食时间,减少警戒时间。在草洲和浅水两种生境中,白鹤的游走和理羽行为存在显著差异,而觅食和警戒行为没有显著的差异,这可能源于草洲和浅水生境相互毗邻,并且具有相同程度的人为干扰。GLM分析结果表明,年龄和集群大小、年龄和生境、集群大小和天气、集群大小和生境、天气和生境对白鹤昼间时间分配模式的影响存在显著交互效应。     

盐城灰鹤(Grus grus)越冬种群动态及行为观察

为解盐城灰鹤(Grus grus)的越冬种群动态及行为特征,在盐城保护区设置两条样线,自2008年12月始,连续5个冬季每月一次作种群监测,并观察灰鹤家族群的越冬行为。结果显示,近5年来,盐城越冬灰鹤种群(303~707只)较为稳定,沿海开发对其种群似乎并无负面影响,这可能与灰鹤的食性及生境偏好有关。年龄对灰鹤越冬行为影响显著,幼鹤相较成鹤将花费更多的时间用于采食,而用于警戒的时间较少,这与幼鹤所处的生长及学习阶段有关。家族群大小对灰鹤的采食、警戒及群体警戒效率等均无显著影响,说明对于灰鹤而言,两只幼鹤并未显著增加其在警戒行为上的投入。     

鄱阳湖滨藕塘生境中白鹤取食行为研究

2016年12月—2017年2月和2017年12月—2018年1月,采用焦点动物法对鄱阳湖滨藕塘生境中白鹤(Grus leucogeranus)的取食行为进行观察,共记录921只次成鹤和547只次幼鹤的取食行为。结果表明,白鹤栖息水深为(17.29±8.75)cm(n=1468),取食水深为(18.84±10.32)cm(n=600),单次取食持续时间为(3.10±1.69)s(n=600),取食频次为(12.24±3.89)次/min(n=1012),取食成功频次为(1.78±1.59)次/min(n=1468),取食成功率为(16.26±14.41)%(n=1012)。成鹤取食成功频次(SymbolcA@~2=70.797,df=1,P=0.000)和取食成功率(SymbolcA@~2=5.356,df=1,P=0.020)均显著高于幼鹤,表明成鹤取食能力较幼鹤强,成鹤可以获得更多的能量。成鹤除维持自身能量支出外,还需要花费较多的能量用于辅食和警戒行为。成幼鹤的取食频次和单次取食持续时间无显著差异,这与成幼鹤的体型大小、能量需求和体内氧气储存量类似有关,也与多数研究认为幼鹤觅食经验不足,觅食成功率低,需要靠多次取食来补偿能量的观点不同。成鹤取食水深极显著高于幼鹤(SymbolcA@~2=50.945,df=1,P0.0001),这可能与体型和取食经验有关。不同栖息水深下白鹤的取食成功率(SymbolcA@~2=15.297,df=4,P=0.004)和取食成功频次(SymbolcA@~2=23.155,df=4,P0.0001)均存在极显著差异。不同时段的取食频次、取食成功频次和取食成功率均无显著差异,这可能与藕塘生境中白鹤采取触觉取食有关。此外,白鹤昼间取食行为无明显节律性,因此昼间能量需求相似,取食参数没有显著差异。     

鄱阳湖越冬白鹤家庭行为

2012年11月至2013年3月,采用焦点取样法,对在江西鄱阳湖国家级自然保护区内越冬的白鹤(Grus leucogeranus)家庭行为进行了研究。结果表明,以家庭为活动单位的白鹤群,成年白鹤活动时间分配比例为:取食80.9%、警戒10.5%、理羽4.0%、游走3.9%、其他0.7%;越冬早期,成年白鹤游走行为的日节律呈现早、晚高,中午低,低谷在10:30~12:30时;越冬晚期,13:00~14:00时出现明显的取食低谷及警戒、游走和理羽的高峰;而越冬早期、中期的理羽高峰出现在14:00~15:00时;成年白鹤雄性与雌性的活动时间分配比例差异不显著;越冬期早、中、晚三个时期,成年白鹤的警戒(F=3.45,P=0.040)、理羽(F=6.99, P=0.001)及游走(F=7.79, P=0.001)行为比例差异显著。幼鹤活动时间分配比例与成年白鹤差异非常显著。幼鹤活动时间分配比例为:取食66.2%、乞食14.0%、警戒3.7%、理羽5.4%、游走3.6%、其他7.1%。雄性成鹤对幼鹤的喂饲频次呈递减趋势,雌性成鹤对幼鹤的喂饲频次从11月底到12月初呈上升趋势,12月中旬以后呈递减状态。整个越冬期,雄、雌成鹤喂饲幼鹤频次无显著性别差异(P=0.340),但越冬中期(P<0.001)及晚期(P=0.005)表现出极显著差异。随着幼鹤的成长,其活动时间节律发生较大变化;幼鹤取食行为比例明显增加,同时其乞食行为的比例显著减少,警戒行为比例显著增加。本次研究从行为学的角度展示了成年白鹤性别差异、幼鹤的生长过程及成鹤对幼鹤生长的重要性。     

云南纳帕海越冬黑颈鹤日间行为模式与年龄和集群的关系

2006年10月—2007年5月,在云南省西北部纳帕海,采用路线调查结合瞬时扫描行为取样法,对越冬黑颈鹤(Grus nigricollis)种群的时间分配及其与年龄、集群和时间的关系进行了观察。结果说明,黑颈鹤越冬活动主要是以觅食为主,占日间时间的(76.81±9.1)％。越冬期间黑颈鹤日间行为的节律性较为明显,具有适应高寒气候的特点。集群形式对成鹤的行为有着显著影响,集群和家庭中活动的成鹤在觅食、警戒和争斗中存在显著差异(F1,76= 0.27、0.77, U= 279, P= 0.001—0.000)。年龄是影响鹤群行为的因素之一。幼鹤相比成鹤有较多的觅食时间和休息时间,警戒行为比例较低(F1,76= 0.04—2.59, U= 188—299, P= 0.006—0.000),且不受集群形式的影响。随着越冬期间的早、中、晚3个时期的环境变化,黑颈鹤的时间分配有显著变化(F2,36= 4.63—26.54, &#61539;22= 5.29—13.68, P= 0.0016—0.000)。不同越冬地的黑颈鹤行为存在差异。气候、食物资源和人为影响可能是造成这些差异的主要因素。     

越冬期黑颈鹤个体行为生态的研究

越冬期黑颈鹤的个体行为可分为：取食、保养、争斗、警戒、运动行为、种间关系及领域性。随着冬季食物资源的逐渐减少,在取食行为中幼鹤由乞食、被成鹤供食转为向成鹤抢食。有些家族鹤为保证食物资源而建立领域,领域大小与家族内成员数无关,且在冬季（甚至１天内）是变化的。为获得食物和保卫领域,黑颈鹤之间（或与灰鹤之间）常发生争斗,争斗的主要形式是仪式化威胁。     

昆明翠湖越冬红嘴鸥日间行为节律及行为时间分配

昆明翠湖是昆明越冬红嘴鸥Larus ridibundus的重要栖息地之一。为了解红嘴鸥越冬期的日间行为模式,掌握其活动规律,2017年11月—2018年2月和2018年11月—2019年2月,采用瞬时扫描法在翠湖水域对越冬红嘴鸥日间行为节律及行为时间分配进行了研究,采用Kruskal-Wallis H检验、单因素方差分析对不同时段内越冬红嘴鸥行为时间分配的差异进行了分析,并采用Pearson检验法检验了各行为间的相关性。结果表明,越冬期红嘴鸥行为时间分配比例为:觅食(44.01±1.70)%、休息(18.84±0.93)%、修整(9.44±1.00)%、警戒(2.45±0.57)%、行走(3.01±0.39)%、游泳(13.77±1.01)%和飞行(8.47±0.68)%。其中,行走和飞行行为在日间各时段内的差异有高度统计学意义(P0.01),具有明显的日节律性变化,其他行为之间的差异无统计学意义;觅食(F=9.112,P0.01)、休息(F=12.798,P0.01)行为在不同月份间的差异有高度统计学意义,而警戒行为在不同月份间的差异有统计学意义(F=3.358,P0.05),具有明显的月节律性变化。昆明翠湖越冬红嘴鸥在整个越冬期间以补充、积累能量为主;日间行为存在明显的"上午觅食+中午休息+下午觅食"的行为模式,一天中最主要的行为是觅食。     

鄱阳湖越冬鹤鹬的日间行为节律

目前有关鸟类越冬行为节律的研究主要集中在大型水鸟。与大型鸟类相比,小型鸟类在体温调节中消耗的能量更多,因此可能呈现不同的日间行为节律。本研究选择鄱阳湖数量较大的小型水鸟——鹤鹬Tringa erythropus为研究对象,于2014年11月—2015年3月在鄱阳湖的子湖——常湖池对越冬期鹤鹬各种行为的时间分配进行了调查研究。结果表明觅食(61.4%)和休息(32.1%)是鹤鹬越冬期最主要的行为,2种行为的比例呈显著负相关。与一些植食性水鸟相比,肉食性鹤鹬的觅食行为比例偏低。而与一些大型食肉性水鸟相比,鹤鹬的觅食行为比例偏高,这可能与其较小的体型在体温调节中消耗的能量较多有关。鹤鹬的警戒行为比例较低(0.8%),越冬期集大群的习性可能是导致其偏低的主要原因。越冬期不同月份间各行为比较中,1月出现了觅食行为比例的高峰和休息行为比例的低谷,这可能与1月平均气温为全年最低有关。觅食行为比例在全天呈缓慢上升趋势,而休息行为比例呈下降趋势。虽然觅食和休息行为的时间分配在全天有一定变化,但是鹤鹬的日间行为节律性并不强。鹤鹬的觅食行为主要发生在跗跖位(0~5.5 cm),而休息行为主要发生在跗跖上位(5.5~8.6 cm),安全性和食物的可利用性可能是影响鹤鹬生境选择的主要因素。     

Diet Shift and Its Impact on Foraging Behavior of Siberian Crane (Grus Leucogeranus) in Poyang Lake

The study of habitat selection and diet has a long history in ecology. This is often used to assess the functional roles of wetland in biodiversity conservation. Shifting habitat and diet may be one of the survival strategies during extremely adverse conditions. Therefore, sudden changes in habitat selection may indicate the deterioration of the habitat quality, and management interventions are necessary. Siberian crane (Grus leucogeranus) became critically endangered due to loss of habitat, and is currently a global conservation focus. Every winter, more than 95% of the species'' global population congregates at Poyang Lake, and feeds on tubers of Vallisneria spiralis in shallow water and mudflat habitat. In this study, we reported the first sighting of large numbers of Siberian cranes foraging at wet meadows, where they fed on a different plant, Potentilla limprichtii due to extreme scarcity of their preferred tuber. To understand how well the cranes adapted to such unusual habitat, field surveys to assess the distribution of cranes across different habitats, and food availability in each habitat were carried out in the winter of 2011. Field observations on crane behaviors at different habitats were also conducted. Results show that cranes displayed significantly different behavior patterns when using the wet meadow, compared to the crane''s optimal habitat - shallow water and mudflat. Both juveniles and adults spent significantly less time foraging, and more time alerting in meadows than in shallow waters and mudflats. These results indicated that the meadow might be a suboptimal wintering ground for Siberian crane, which helped the cranes survive from extreme unfavorable conditions. To some degree, this finding alleviates the general concern over the fluctuating of its food resources which was caused by hydrological disturbances. However, more studies are needed to assess the consequences of such diet and habitat shift for crane survival.     

基于多源遥感的贵州草海国家级自然保护区黑颈鹤生境适宜性评价

生境适宜性评价是保护和管理濒危物种的重要途径。已有研究中用于物种生境适宜性评价的环境变量数据多存在分辨率低精度不高的问题,在研究小尺度物种生境适宜性时误差较大。为解决这一问题,本文根据黑颈鹤的出现点数据与光学、雷达遥感数据及地形辅助数据得出栖息地与觅食地特征,利用最大熵(MaxEnt)模型对草海越冬黑颈鹤细尺度的生境适宜性进行评价。结果显示：(1)运用多源遥感和地形辅助数据生成的环境变量结合MaxEnt预测黑颈鹤的栖息地与觅食地效果都较为优秀,两者受使用者工作特征曲线下的面积值(AUC)值均大于0.94;(2)距耕地距离、距水域距离、水深及距建筑距离是影响黑颈鹤栖息地主要环境因子,而影响觅食地分布的主要环境因子则是距耕地距离、优势植被、距建筑物距离和水深。(3)草海自然保护区黑颈鹤栖息地与觅食地的最适宜区和次适宜区面积较小,栖息地与觅食地最、次适宜区总和分别为6.404km~2与12.644 km~2,占比仅为研究区的6.43%和12.69%。通过调查发现,当前自然保护区的人为干扰源主要是游客和当地的居民,潜在地威胁着黑颈鹤的栖息地和觅食地。因此,为了避免保护区黑颈鹤栖息地与觅食地的退...     

Behavior of early life intervals of Klamath River green sturgeon, <Emphasis Type="Italic">Acipenser</Emphasis><Emphasis Type="Italic">medirostris</Emphasis>, with a note on body color

We studied ontogenetic behavior, migration, and wintering behavior of young Klamath River green sturgeon, Acipenser medirostris, in the laboratory to provide insight into likely behavior of wild sturgeon. Hatchling free embryos preferred cover but were poor swimmers and could not move farther than a few centimeters to cover. The poor swimming ability and cover preference of hatchlings suggests evolution for habitat selection of females to place eggs in habitat with cover for eggs (and hatchlings), and for egg characteristics (large, dense, and weakly adhesive) to cause rapid sinking into cover without drifting. A day or so after fish developed into larvae (first life interval feeding exogenously), day-12 larvae initiated a 12-day downstream nocturnal migration. A totally nocturnal migration is unlike other Acipenser migrants yet studied. Migrant larvae had a dark-colored body typical of other Acipenser species that migrate as larvae. Tail color was a dark black (black-tail phenotype) only during the early larva period, suggesting a morphological adaptation for migration, foraging, or both. Post-migrant larvae and early juveniles to day 84 foraged diurnally with a nocturnal activity peak. Day 110–181 juveniles moved downstream at night until water temperature decreased to about 8°C, indicating wild juveniles migrate downstream to wintering habitat. Habitat preference of month 9–10 wintering juveniles suggests wild juveniles are in deep pools with low light and some rock structure. Wintering juveniles were only active at night. Initiation and cessation of daily activity was at dusk and dawn during illumination changes of <1.0lx. This sensitivity to illumination has not been found before in sturgeons. During the first 10months of life, nocturnal activity of early life intervals is a dominant feature of migration, foraging, and wintering.     

西藏拉萨越冬黑颈鹤家庭群的警戒同步性

以往关于动物警戒行为的研究多以经典随机独立模型为基础,然而,近期一些理论和实证研究则向该模型发出了挑战。根据警戒行为同步性程度的不同,集体警戒可能存在基于模仿的同步警戒和避免重复的协调警戒两种模式。研究了中国雅鲁藏布江自然保护区越冬黑颈鹤家庭群的警戒行为,通过独立样本t检验验证由于年龄和是否携幼所导致的个体警戒水平的差异,通过单因素方差分析比较不同类型家庭群的集体警戒水平,通过配对t检验比较集体警戒的实际观测值和独立假设下的预期值从而确定越冬黑颈鹤家庭群的警戒同步性。结果表明家庭群中的幼年黑颈鹤警戒行为时间显著低于成年黑颈鹤,但幼鹤的存在对成鹤的警戒水平没有显著影响。不同类型黑颈鹤家庭群的集体警戒水平没有差异,但并未如预期表现为同步警戒。警戒行为模式是动物在特定环境中的适应性表现,越冬黑颈鹤生境中不存在落后目标策略的捕食者和高强度的捕食风险,因而可能不足以诱发以降低捕食风险为主要功能的高强度的警戒行为同步性;同时,在资源匮乏的冬季对食物获取的优先性可能也削弱了对同步警戒的需求。     

Interannual variation in the at‐sea behavior of California sea lions (Zalophus californianus)

To be successful, marine predators must alter their foraging behavior in response to changes in their environment. To understand the impact and severity of environmental change on a population it is necessary to first describe typical foraging patterns and identify the underlying variability that exists in foraging behavior. Therefore, we characterized the at‐sea behavior of adult female California sea lions (n = 32) over three years (2003, 2004, and 2005) using satellite transmitters and time‐depth recorders and examined how foraging behavior varied among years. In all years, sea lions traveled on average 84.7 ± 11.1 km from the rookery during foraging trips that were 3.2 ± 0.3 d. Sea lions spent 42.7% ± 1.9% of their time at sea diving and displayed short (2.2 ± 0.2 min), shallow dives (58.5 ± 8.5 m). Among individuals, there was significant variation in both dive behavior and movement patterns, which was found in all years. Among years, differences were found in trip durations, distances traveled, and some dive variables (e.g., dive duration and bottom time) as sea lions faced moderate variability in their foraging habitat (increased sea‐surface temperatures, decreased upwelling, and potential decreased prey abundance). The flexibility we found in the foraging behavior of California sea lions may be a mechanism to cope with environmental variability among years and could be linked to the continuing growth of sea lion populations.     

Vigilance and Activity Time-Budget Adjustments of Wintering Hooded Cranes,Grus monacha,in Human-Dominated Foraging Habitats

Due to loss and degradation of natural wetlands, waterbirds increasingly rely on surrounding human-dominated habitats to obtain food. Quantifying vigilance patterns, investigating the trade-off among various activities, and examining the underlying mechanisms will help us understand how waterbirds adapt to human-caused disturbances. During two successive winters (November-February of 2012–13 and 2013–14), we studied the hooded crane, Grus monacha, in the Shengjin Lake National Nature Reserve (NNR), China, to investigate how the species responds to human disturbances through vigilance and activity time-budget adjustments. Our results showed striking differences in the behavior of the cranes when foraging in the highly disturbed rice paddy fields found in the buffer zone compared with the degraded natural wetlands in the core area of the NNR. Time spent vigilant decreased with flock size and cranes spent more time vigilant in the human-dominated buffer zone. In the rice paddy fields, the birds were more vigilant but also fed more at the expense of locomotion and maintenance activities. Adult cranes spent more time vigilant and foraged less than juveniles. We recommend habitat recovery in natural wetlands and community co-management in the surrounding human-dominated landscape for conservation of the hooded crane and, generally, for the vast numbers of migratory waterbirds wintering in the middle and lower reaches of the Yangtze River floodplain.     

How do vigilance and feeding by common cranes Grus grus depend on age,habitat, and flock size?

Animals often spend less time vigilant and more time feeding when foraging in larger groups. This group-size effect does not, however, consider if larger groups differ systematically from smaller ones: Large groups could form in different habitats than small groups or be composed of a different mix of ages or classes than small groups. We examined how habitat differences and flock size and composition explain feeding and vigilance rates in common cranes Grus grus , wintering in holm oak Quercus ilex dehesas of Spain. Flock size and composition were related to habitat type in cranes: flocks formed in areas sown with cereal crops were larger than flocks formed in set aside areas. Vigilance rate depended on habitat but decreased with increasing flock size in a similar way across all habitats. Juveniles were less vigilant than adults and showed little change in vigilance with flock size. Vigilance increased and feeding time decreased over months from November through February. Our results show that vigilance is affected by habitat but that the group size effect on vigilance is not the product of differences between habitats in group size or composition.     

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...