Reproductive ecology of the endangered Beal's-eyed turtle, Sacalia bealei

PeerJ. 2018 Jun 14:6:e4997. doi: 10.7717/peerj.4997. eCollection 2018.

Abstract

The Beal's-eyed turtle (Sacalia bealei) is endemic to southeastern China and endangered due to poaching and habitat loss. Knowledge of S. bealei ecology is lacking and this study provides baseline information of its reproduction in a natural environment. We studied the reproductive ecology of S. bealei using X-ray, spool-and-line tracking, and direct observation. Six nesting females were successfully tracked and their nesting behaviors are documented in detail. Females produced a mean clutch size of 2.2 eggs (range 1-3). The hard-shelled eggs were ellipsoidal with a mean length of 45.50 mm, a mean width of 23.20 mm, and mean weight of 14.8 g. The relative clutch mass was 9.47%, while the relative egg mass was 4.60%. The mean incubation period was 94.7 days with a mean nest temperature of 25.08 °C. Hatchlings had a mean weight of 9.7 g, carapace length of 40.1 mm, carapace width of 33.3 mm, carapace height of 17.4 mm, plastron length of 31.6 mm, and plastron width of 25.4 mm. The results of this study provide important information to inform conservation plans and ex-situ breeding for this endangered species.

Keywords: Animal behavior; Beal’s Eyed Turtle; Conservation; Ecology; Incubation; Nesting behavior; Turtle conservation.

Grants and funding

This study was supported by the National Nature Science Foundation of China (31772486), Hainan College Scientific Research Project (Hnky 2015–26) and the Croucher Foundation Chinese Visitorship. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.