Testing reintroduction as a conservation strategy for the critically endangered Chinese alligator: Movements and home range of released captive individuals  

作　　者：WANG ZhengHuan YAO Hong DING YouZhong THORBJARNARSON John WANG XiaoMing 

机构地区：[1]School of Life Sciences, East China Normal University, Shanghai 200062, China [2]Shanghai Key Laboratory of Urbanization and Ecological Restoration, East China Normal University, Shanghai 200062, China [3]Wildhfe Conservation Society, 2300 Southern Boulevard, Bronx, New York 10460, USA [4]Shanghai Science and Technology Museum, Shanghai 200171, China

出　　处：《Chinese Science Bulletin》2011年第24期2586-2593,共8页

基　　金：Technically and finan-cially supported by the World Conservation Society (WCS)

摘　　要：The Chinese alligator (Alligator sinensis) is considered the most critically endangered crocodilian as a result of the near total loss of its habitat and its extremely small and fragmented wild populations. Plans for population recovery lie mostly with wetland res- toration and the reintroduction of captive-reared animals. We carried out a first-trial release of 3 adult Chinese alligators (1♂, 2♀) into a pond at the Hongxing conservation site, Xuancheng, southern Anhui Province; the animals were radio-tracked from May to October in 2003. We hypothesized that after a period of adaptation, the alligators would establish definable home ranges. Two (1♂, 1♀) of the 3 alligators were monitored for the whole of the tracking period. The male had an annual home-range size of 7.61 hm2, and the female 4.00 hm2. Water temperature and pond water level were two important factors influencing the alligators' distributions, and daily movements. The radio-tracked alligators had overlapping home ranges, which notably included the one substantial island in the pond; that island is the only known nesting site of the local native wild alligators. Aggressive interactions between the released alligators and native wild alligators were observed during the breeding season around this island. All the three reintroduced alligators survived the winter of 2003 and were alive in the same pond in 2008. We concluded that the Hongxing conservation site provided a suitable habitat for the reintroduced alligators. However, the low water level in the pond resulting from farmland irrigation in August and September can be a substantial threat to the alligators' survival. Therefore, regu- lations on irrigation in summer and autumn are needed to balance the water needs of the alligators and agriculture.The Chinese alligator （Alligator sinensis） is considered the most critically endangered crocodilian as a result of the near total loss of its habitat and its extremely small and fragmented wild populations. Plans for population recovery lie mostly with wetland restoration and the reintroduction of captive-reared animals. We carried out a first-trial release of 3 adult Chinese alligators （1♂, 22） into a pond at the Hongxing conservation site, Xuancheng, southern Anhui Province; the animals were radio-tracked from May to October in 2003. We hypothesized that after a period of adaptation, the alligators would establish definable home ranges. Two （1♂, 1 ♀） of the 3 alligators were monitored for the whole of the tracking period. The male had an annual home-range size of 7.61 hm2, and the female 4.00 hm2. Water temperature and pond water level were two important factors influencing the alligators＇ distributions, and daily movements. The radio-tracked alligators had overlapping home ranges, which notably included the one substantial island in the pond; that island is the only known nesting site of the local native wild alligators. Aggressive interactions between the released alligators and native wild alligators were observed during the breeding season around this island. All the three reintroduced alligators survived the winter of 2003 and were alive in the same pond in 2008. We concluded that the Hongxing conservation site provided a suitable habitat for the reintroduced alligators. However, the low water level in the pond resulting from farmland irrigation in August and September can be a substantial threat to the alligators＇ survival. Therefore, regulations on irrigation in summer and autumn are needed to balance the water needs of the alligators and agriculture.

关 键 词：野生扬子鳄 动物放归 保护 运动 濒危 无线电跟踪 家庭 测试 

分 类 号：S863[农业科学—野生动物驯养] Q959.64[农业科学—畜牧兽医]