Study On Behaviorally Thermoregulation Of Chinese Alligator Under Artificial Feeding Condition

Chinese alligator (Alligator sinensis) belongs to Reptilia, Crocodylia, Alligoridae. It only distributes in China. Due to the destruction of Chinese alligator habitant, the population in the wild is less than 120 individuals; Chinese alligator has been listed as the top priority species of the 23 Crocodilians by expert team of IUCN. The ways to Chinese alligator conservation and research hotspot are habitat restoration and population rejuvenation in the wild by captive population. Therefore, researching on Chinese alligator's behavioral adaptation to environment is of very important meaning to the conservation of Chinese alligator and the restoration of its habitat.The behavioral thermoregulation of adult Chinese Alligators (Alligator sinensis), in Zhejiang Changxing Nature Breeding Research Center for Chinese Alligator, was studied from June to October 2005 and from April to May 2006, recording by instantaneous and scan sampling methods. We established a behavior coding of Chinese Alligator based on its daily activity, including swimming, head out of the water, head and back out of the water, creeping and lowering its head with mouth closed, gaping and creeping and rising its head with mouth closed. Chinese Alligators spent more time in water, head out of the water was the most behavior, accounted for 52.3% and 46.0%, and gaping was the least behavior, accounted for 1.8% and 1.5%. In two kinds of temperature environment, there are not differences among head out of the water (Z = - 0.554, P > 0.05), creeping and lowering its head with mouth closed (Z = - 578, P > 0.05) and gaping (Z = -0.643, P > 0.05), however, there are significant differences among Swing (Z= - 6.521, P < 0.01),head and back out of the water (Z = -5.823, P < 0.01) and rising its head with mouth closed (Z = - 5.496, P < 0.01).Chinese Alligator performed regular activities between water and land. Most Chinese Alligator began entering the water in 6:00-8:00 and landing in 18:00-20:00 in higher temperature, Most Chinese Alligator began landing in 6:00-8:00 and entering into the water inl8:00-20:00 in lower temperature. The most important factors that influence the activities between water and land of Chinese alligator should be the difference between water and air temperature and sunlight. Under cloudy and overcast condition, the weather influence on Chinese alligator activity is significant only in lower temperature. Resting on the bank with part of under the water was observed. Theresult show that Chinese Alligator chose the environmental temperature not exceed 31±1℃.