Microhabitat selection of the big-headed turtle Platysternon megacephalum in the Hainan Tropical Rainforest National Park, China

Understanding species habitat requirements is vital for ensuring the success of targeted conservation and habitat restoration measures. The big-headed turtle (Platysternon megacephalum) is a freshwater species which is distributed across Southeast Asia. Due to the human threats posed by illegal pet trade and overharvesting for food and medicinal purposes, the species has undergone rapid decline. Furthermore, limited research has been conducted on this species, particularly regarding habitat preferences on Hainan Island, China. Therefore, this study examined the microhabitat selection of P. megacephalum using cage and sample plot methods in the Diaoluo Mountain area of the Hainan Tropical Rainforest National Park. Our results indicated that big-headed turtles select stream microhabitats at higher altitudes, in proximity to rocky substrates, several caves, and high diversity of food sources. Microhabitat utilization did not differ significantly between adults and juveniles. This suggests that protecting microhabitats and main food sources is important for the conservation of P. megacephalum. Our findings provide a reference for the protection of this species in Jianfeng, Yingge Ridge, and other areas in the Hainan Tropical Rainforest National Park.