Conservation

Platysternon magacephalum : Asian Big-headed Turtle

Photo by Susan Tiedemann

Big-Headed Turtles - Platysternon megacephalum

by Russ Gurley

Comments: Big-headed Turtles are grouchy and independent, and exhibit a life history quite unlike any other turtle, lumbering up and down mountain streams and waterfalls and even climbing shrubs and small trees in search of prey! (Pritchard, 1979).

Distribution: Big-headed Turtles are found from China and Vietnam south to Thailand and Myanmar.

Adult Size: Depending on the species, Big-headed Turtles are typically in the 5” to 7” (18 cm) range with some specimens growing to 11”.

Captive Care: In nature, Big-headed Turtles inhabit solitary pools associated with cold mountain streams. Therefore, their captive environment should reflect this habitat and its characteristics.

Indoors, Big-headed Turtles behave similarly to other aggressive species such as Carettochelys , Staurotypus , Erymnochelys, and Chelydra . There is a definite need to separate individuals so they don't fight. Males are especially aggressive and often attack each other violently. Interestingly, they often ignore other species kept with them. At the Turtle and Tortoise Preservation Group, we have used 40-gallon aquariums to set up Big-headed Turtles individually. We paper over the glass sides to make them feel more secure. Water is kept shallow (5” to 6”) and cool (68º to 74º F). We offer them double the amount of filtration to ensure that their water is clean and highly oxygenated. We use sand as a substrate and offer them lots of driftwood and piles of slate for exploring and hiding. Basking spots are established over the piles of slate. These spots are maintained at about 85º F (29 ºC) with the use of a 75-watt bulb.

Outside, we have used medium tubs (36”w x 72”l x 12”deep) for single specimens and large tubs (48”w x 84”l x 24”deep) or stock tanks for keeping trios of Big-headed Turtles. The water is pumped via a submersible pond pump through a pre-filter and into a small water fountain to add oxygen to the pond. We add lots of slate and piles of rock to allow them to separate themselves from each other. In these outdoor ponds, they often wedge themselves into pockets or folds of pond liners and into rock crevices away from each other – spread far apart, even in the largest outdoor enclosure.

Care must be taken that the Big-heads' outdoor enclosure is in a shady area, especially in areas where the summers are quite warm. In addition to the pond fountains, we cover the surface of their pond with a layer of aquatic plants and on the hottest days, we spray water onto the surface of the water from a garden hose or sprinkler to beat the heat and to add oxygen to the system.

Feeding: “Bigheads” feed aggressively on earthworms, fish, and other live prey and will acclimate to take commercial pellets as part of a varied diet.

Common Health Problems: Obesity. We offer our “Bigheads” lots of creative spaces, used as exercise areas, and feed them only three times a week. The combination of activity and reduced feeding has produced healthy, alert specimens with no signs of captivity-related obesity or stress.

Big-headed Turtles often display scars or injuries from fighting. One common trademark of an individual kept with too many others is a lack of the tip of the tail. Apparently, when confined together for any length of time, they lash out with their sharp jaws at the closest turtle's vulnerable parts. Several Chinese shipments a few years ago arrived with only one or two out of twenty-five that had complete tails. These turtles should therefore be shipped in individual containers or in a box with compartments. (See IATA Shipping, Appendix II.) In cramped captive quarters they will not only bite off each other's long tails, but will also cause considerable damage to each other's feet, heads, eyes, and necks.

Newly imported specimens should be vet-checked for dehydration, respiratory problems, and parasites, and treated appropriately.

Breeding: There have been very few successful captive breedings of Big-headed Turtles in recent years. Most baby Big-headed Turtles have been produced from eggs that have been dropped by imported females in shipping containers or soon after their arrival. Several lucky babies have been produced from eggs that have been collected from the water or the land area of a “Bighead” enclosure. A few turtle keepers are experimenting with injecting imported female Asian turtles with oxytocin in an effort to get eggs and to develop small colonies of captive-hatched turtles that do not present the problems of imported animals. Time will tell if this plan will be viable.

Only a few private breeders have had the pleasure of seeing beautiful hatchling Big-headed Turtles emerge from eggs. The babies have beautiful orange plastrons and apple-green carapaces. They reportedly pip and emerge quite quickly, literally popping out of the egg when hatching (Tiedemann, pers. com.). In addition to being quite active and secretive, hatchling and young Big-headed Turtles will squeak loudly if they are handled or disturbed!

SUGGESTED READING

Humphrey, S. R. and J. R. Bain. 1990. Endangered Animals of Thailand. Flora and Fauna Handbook No. 6. Sandhill Crane Press, Gainesville, Florida.

Karsen, S. J., M. W. Lau, and A. Bogadek. 1986. Hong Kong Amphibians and Reptiles. Urban Council, Hong Kong.

Walsh, T. and M. Russell. 1998. The Natural History and Captive Husbandry of the Big-Headed Turtle ( Platysternon megacephalum ). Reptiles magazine (Feb. '98) 6(2): 66-75.

* Excerpt from Gurley, R. 2003. KEEPING and BREEDING FRESHWATER TURTLES . Living Art publishing. 305 pp.