Trip report: CSG visit to China, August 2016

Published source details Manolis C., Shirley M.H., Siroski P., Martelli P., Tellez M., Meurer A. & Merchant M. (2016) Trip report: CSG visit to China, August 2016. IUCN-SSC Crocodile Specialist Group report, 13pp.
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This study is summarised as evidence for the following.

	Action	Category
	Release captive-bred reptiles into the wild: Crocodilians Action Link
	Create or restore ponds Action Link
	Release captive-bred reptiles into the wild: Crocodilians Action Link
	Breed reptiles in captivity: Crocodilians Action Link

Release captive-bred reptiles into the wild: Crocodilians

A replicated study in 2006–2016 in an area of ponds and dense vegetation in Anhui Province, China (Manolis et al. 2016) found that after 10 years of releases of captive-bred Chinese alligators Alligator sinensis, alligators occupied over half of ponds in the area, and successful reproduction was occurring. Alligators were found in 28 of the 50 ponds (56%). Survivorship of released alligators was thought to be >85% (no formal analysis carried out). Successful reproduction was recorded two years after the first release (158 eggs, producing 80 hatchlings were discovered), though the full extent of nesting was unknown. Fifty ponds (30 ha total water area) were constructed in the release area, at a cost of around $US10,000 to construct and prepare the average-sized pond. Ponds were established with terrestrial (e.g. bamboo) and aquatic vegetation, and “seeded” with fish, amphibians, and snails. Prior to release, adult alligators were isolated for 3–4 months for health screening. In 2006–2016, eleven releases (during May–June) of 93 alligators were carried out (sex ratio 1 male:2 females). Population monitoring was carried out using spotlight surveys.

(Summarised by: William Morgan)
Create or restore ponds

A replicated study in 2006–2016 in an area of ponds and dense vegetation in Anhui Province, China (Manolis et al. 2016) found that around half of constructed ponds were used by Chinese alligators Alligator sinensis following the release of captive bred individuals. Alligators were distributed among 28 of 50 constructed ponds. Successful reproduction was recorded two years after the first release (158 eggs, producing 80 hatchlings were discovered), though the full extent of nesting was unknown. Fifty ponds (30 ha total water area) were constructed in the release area, at a cost of around $US10,000/pond. Ponds were established with terrestrial (e.g. bamboo) and aquatic vegetation, and “seeded” with fish, amphibians and snails. In 2006–2016, eleven releases (during May–June) of 93 alligators were carried out (sex ratio 1 male:2 females) and population monitoring was carried out using spotlight surveys.

(Summarised by: William Morgan)
Release captive-bred reptiles into the wild: Crocodilians

A study in 2007–2016 in a wetland in Shanghai Province, China (Manolis et al. 2016) reported that some released captive-bred Chinese alligators Alligator sinensis survived for 1–9 years and successfully reproduced. Three of six alligators survived for 9 years, and a further six survived at least one year following release. Nesting was reported in four years following release. In 2016, the population consisted of nine adults (released individuals), at least four wild born adults (offspring of released alligators) and around five juveniles/sub-adults. In 2007, six captive-bred alligators were released into a wetland park. In 2015–2016 a further six were released.

(Summarised by: William Morgan)
Breed reptiles in captivity: Crocodilians

One study in 1982–1985 and 2006–2016 in a captive facility in Xuancheng, Anhui Province, China (Manolis et al. 2016) reported that a captive population of Chinese alligators Alligator sinensis increased over a 10-year period. The captive population grew from 10,000 individuals in 2006 to 15,000 in 2016. In 1982–1985, wild alligators (212 individuals) and nests (778 eggs) were brought in to captivity as part of a breeding programme.

(Summarised by: William Morgan)