Abstract
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♂, 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, regulations on irrigation in summer and autumn are needed to balance the water needs of the alligators and agriculture.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
Brooks T M, Mittermeier R A, Mittermeier C G, et al. Habitat loss and extinction in the hotspots of biodiversity. Conserv Biol, 2002, 16: 909–923
Biodiversity Committee of Chinese Academy of Science. Biodiversity in China: Status and Conservation Needs (in Chinese). Beijing: Science Press, 1992
Thorbjarnarson J, Wang X M. The conservation status of the Chinese alligator. Oryx, 1999, 33: 152–159
Wang S, Xie Y. China Species Red List (Vol. 1) (in Chinese). Beijing: Higher Education Press, 2004
Chen B H. Chinese Alligator (in Chinese). Hefei: Anhui Science and Technology Press, 1985
Huang C. The ecology of the Chinese alligator and changes in its geographical distribution. In: Crocodiles. Proceedings of the 5th Working Meeting of the IUCN/SSC Crocodile Specialist Group, Gland, 1982. 54–62
Huang Z J, Lin H Z, Zhang S K. An analysis of the remote sensing image of the Chinese alligator’s habitat (in Chinese). Oceanol Limnol Sin, 1985, 16: 35–41
Wang W, Gu C M, Wang G S. Protection and management project of the existing wild population of Alligator sinensis in Anhui Province. In: Department of Wildlife Conservation State Forestry Administration, ed. Status Qui and Future of Conservation for Chinese Alligator and Crocodiles in the World. Beijing: China Forestry Publish House, 2002. 37–47
Zhu C G. Chinese alligator (in Chinese). Bull Biol, 1954, 9: 9–11
Zhu C G. Observations on the life history of Chinese alligator (Alligator sinensis) (in Chinese). Acta Zool Sin, 1957, 9: 129–143
Thorbjarnarson J, Wang X M, Shao M et al. Wild populations of the Chinese alligator approach extinction. Biol Conserv, 2002, 103: 93–102
Ding Y Z, Wang X M, Wang Z H, et al. Observation of activity in Chinese alligators released during an early period at Hongxing of Hanhui (in Chinese with English summary). Zool Res, 2004, 25: 27–31
Rao R J. Gharial re-introduction in Chambal River, India: A success story. Re-introduction News, 2006, 25: 16–17
Thorbjarnarson J, Wang X M. The Chinese Alligator. Baltimore: The Johns Hopkins University Press, 2010
Wang H, Wang Z H, Wang Z W, et al. Study on behavioral thermoregulation of Chinese alligator under artificial feeding condition (in Chinese). Chinese J Zool, 2006, 41: 60–66
Muñoz M C, Thorbjarnarson J. Movement of captive-released Orinoco Crocodiles (Crocodylus intermedius) in the Capanaparo River, Venezuela. J Herpetol, 2000, 34: 397–403
Zhu H X. Observations on one wild population of Chinese alligator (in Chinese). Sichuan J Zool, 1997, 16: 129–143
White G C, Garrott R A. Analysis of Radio-tracking Data. San Diego: Academic Press, Inc., 1990
Row J R, Blouin-Demers G. Kernels are not accurate estimators of home-range size for Herpeto fauna. Copeia, 2006, 4: 797–802
Worton B J. Kernel methods for estimating the utilization distribution in home-range studies. Ecology, 1989, 70: 164–168
Swihart R K, Slade N A. Testing for independence of observations in animal movements. Ecology, 1985, 66: 1176–1184
Curio E. Conservation needs ethology. Trends Ecol Evol, 1996, 11: 260–263
Sutherland W J. The importance of behaviour in conservation biology. Anim Behav, 1998, 56: 801–810
Reed M J. The role of behaviour in recent avian extinctions and endangerments. Conserv Biol, 1999, 13: 232–241
Caro T. The behaviour-conservation interface. Trends Ecol Evol, 1999, 14: 366–369
He L J, Wang X M, Ding Y Z, et al. Influence of temperature on egg incubation of the wild Chinese alligator (Alligator sinensis) (in Chinese). Acta Zool Sin, 2002, 48: 420–424
Goodwin T M, Marion W R. Seasonal activity ranges and habitat preferences of adult alligators in a north-central Florida lake. J Herpetol, 1979, 13: 157–164
Smith E N. Behavioral and physiological thermoregulation of crocodilians. Am Zool, 1979, 19: 239–247
Chabreck R W. The movement of aliigators in Louisiana. Proc. Southeastern Game and Fish Commissioners Conference, 1965, 19: 102–110
Hutton J. Movements, home range, dispersal and the separation of size classes in Nile crocodiles. Am Zool, 1989, 29: 1033–1049
Kay W R. Movements and home ranges of radio-tracked Crocodylus porosus in the Cambridge Gulf region of Western Australia. Wildlife Res, 2004, 31: 495–508
Joanen T, McNease L. A telemetric study of nesting female alligators on Rockefeller Refuge, Louisiana. Proc Southeastern Assoc Game and Fish Commissioners Conference, 1970, 24: 175–193
Joanen T, McNease L. A telemetric study of adult male alligators on Rockefeller Refuge, Louisiana. Proc Southeastern Assoc Game and Fish Commissioners Conference, 1972, 26: 252–275
Author information
Authors and Affiliations
Corresponding author
Additional information
This article is published with open access at Springerlink.com
Rights and permissions
This article is published under an open access license. Please check the 'Copyright Information' section either on this page or in the PDF for details of this license and what re-use is permitted. If your intended use exceeds what is permitted by the license or if you are unable to locate the licence and re-use information, please contact the Rights and Permissions team.
About this article
Cite this article
Wang, Z., Yao, H., Ding, Y. et al. Testing reintroduction as a conservation strategy for the critically endangered Chinese alligator: Movements and home range of released captive individuals. Chin. Sci. Bull. 56, 2586–2593 (2011). https://doi.org/10.1007/s11434-011-4615-8
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11434-011-4615-8