Article Review: Spatial Ecology of Endangered Big-Headed Turtles (Platysternon megacephalum): Implications of its Vulnerability to Illegal Trapping

This article was written by Yik-Hei Sung, Billy C.H. Hau, and Nancy E. Karraker, and published in The Journal of Wildlife Management in 2015. This article focused on studying the Chinese Big-Headed Turtle’s, Platysternon megaphalum, movement and habitat range. After this, they wanted to see how they could apply their knowledge to help protect these turtles. This species of turtle only exists in the wild in South-East Asia, and their population has been declining at a rapid rate. The authors outlined 3 main objectives: 1) to determine the home range of these turtles, 2) to examine the turtle’s seasonal movement patterns, and 3) to evaluate the habitats of these turtles and to show the variants in the habitats affect their use.

They tracked the turtle’s movements using radiotelemetry, or using radio waves to transmit location information, on 31 adult Big-Headed Turtles. They attacted the devices to the carapaces of the turtles, before releasing them back into their original location. This data was collected from September 2009-June 2011. They tracked adults from two separate streams, both of which had similar characteristics, such as clear, fast moving water. While they did this they also took samples from the habitats every three months to see if there were variables that affected where the turtles went.

The data from this was then analyzed to create a mean home range for the turtles (97m). Of the 31 original turtles, 22 were from the first location and 7 were from the second. From the latter, poachers took 2 of the 7 and their trackers were found in the stream. Because of the low number, they did not use data from that site. Since they had to disregard that part of the experiment they did not get information regarding the seasonal implications on movement.  

This turtle had previously been cited as semi-aquatic, this study found them to be extremely aquatic. The authors pointed out this may be the reason that the turtles are so vulnerable to trapping. They also found the home range of the Big-Headed Turtles are much smaller than other turtles, which also could explain why there are so few of them left. The turtles also seemed to prefer rocky and steep streams, they also like a lot of leaf litter and boulders. These researchers concluded that infrared-triggered cameras be installed to help protect these turtles.  

(On a personal note: this is now my favorite species of turtle) 

Bibliography: Sung, Y., Hau, B. H., & Karraker, N. E. (2015). Spatial ecology of endangered big-headed turtles ( Platysternon megacephalum): Implications of its vulnerability to illegal trapping. Journal Of Wildlife Management, 79(4), 537-543.