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Chitra indica : Narrow-headed Giant Soft-shelled Turtle
The Captive Care of Chitra indica , by Russ Gurley
NATURAL HISTORY Chitra indica , The Giant Narrow-headed Softshell Turtle, is a large softshell turtle found in the rivers of Pakistan, India, Nepal, Bangladesh, Burma, and western Malaysia. (Ernst, 1989). This giant of the turtle world is extremely secretive, spending most of the day submerged in the sandy bottoms of deep rivers. There has been recent speculation about its reported rarity as its lifestyle keeps its behavior and population a mystery. Chitra females pull themselves onto sandy beaches to lay their eggs. This is quite a task due to their incredible bulk and their shape - making them extremely aquatic, yet awkward on land. Like sea turtles, they hurl themselves up the beach to a spot above the flood zone, deposit their eggs, and flop themselves back to the river. Chitra females reportedly can lay from 60 to 110 eggs and there is a report of a female with a carapace length of 110 cm (44 inches) that laid 107 eggs in captivity. The hatchlings from this captive breeding measured 35-40 mm (11/2 to 2 inches) and were brightly marked with dark-bordered light markings on an olive background (Wirot, 1979). ANATOMY Juvenile Chitra have a carapace covered with small tubercles and a vertebral keel (Ernst, 1989). Adults, however, have a smooth, flat carapace. The young are tan to greenish-tan and are covered head-to-toe with splashes and swirls of decorative light markings. Adult Chitra are often uniformly gray, however I have seen several large Chitra which retained the beautiful "juvenile" markings well into their adult size (20-24" and up). This is possibly a geographic variation similar to what has recently been reported with another giant softshell species, Pelochelys bibroni. Externally, Chitra indica is indeed very similar to Pelochelys bibroni , the Asian giant softshell. There is even a population of Pelochelys bibroni in southern New Guinea that is marked similarly with the splashes and lines of light coloration seen in Chitra . However, the skulls of the two turtles are quite different - Pelochelys having a shorter, broader skull and Chitra having a skull that is relatively long and not as broad. Chitra have large paddle-like feet with webbed toes and large claws. These over-sized feet are used to scoop large amounts of sand over their backs when burying in the bottoms of rivers and also make them amazingly powerful swimmers. CAPTIVE CARE A group of C. indica was obtained and after a brief acclimation period, were set up in a 6' round stock tank which will hold approximately 250 gallons of water. A substrate of 4 to 6" of washed medium grade sandblasting sand was introduced and the tank was filled with approximately 250 gallons of fresh, dechlorinated water. Two 200 watt Ebo-Jaeger heaters -set at 27° C (80° F) - and three quarts of aquarium salt were mixed in. A small bed of floating water hyacinth was added. Filtration is carried out via a flow-throw biological system using a Supreme 500 pond kit for a pre-filter. The filter itself consists of a plastic utility sink mounted above the enclosure. The water first flows into a shallow tub that is full of filter padding to remove the larger particles as they arrive at the system. The bottom of the tub is perforated dozens of holes with a soldering iron to allow maximum flow-through drainage. Lava and Bio-Balls are used as the biological filtration layer, located inside the utility sink itself. The outlet hose from the pre-filter sprays the water onto the layer of filter padding and the water flows down through this system and empties back into the Chitra tank through the drain hole in the bottom of the sink. This simple, inexpensive system has proven very effective for many varieties of aquatic turtles and is in use throughout our breeding facilities at The Turtle and Tortoise Preservation Group. The turtles are fed 3-4 times a week. They are offered minnows, goldfish, and other small fish which they consume greedily. So far, Chitra have refused any form of commercial pellet food. Several interesting behaviors related to feeding have been observed. One large male has shown an interesting form of “hand waving”. He fans his large flippers back and forth above his head immediately upon introduction of the prey fish and occasionally even when hands are placed into the tank for cleaning. This activity appears to form a current to "pull" or "coax" small fish towards his mouth. When close enough, his long neck darts out with lightning speed and engulfs any small prey. The smaller turtles in the enclosure tend to remain buried in the sandy bottom with only the tips of their protruding noses and eyes above the substrate. They too quickly snap up any fish that wander close enough. As with most "gulpers", any sand that is taken in with the prey is quickly expelled along with the excess water. Chitra will also aggressively take large fish. The mess that is left after the destruction of this larger prey can cause problems with filtration and water quality, so we feed only “bite-sized” minnows, shiners, goldfish, etc. When obtaining and keeping Chitra or other large softshells, following a few guidelines can help immensely. Care must be taken to keep the water in a softshell enclosure extremely clean. Water degradation can quickly lead to shell and skin infections and sores. As Chitra are large turtles, often reaching over 40" in carapace length, they expel large amounts of waste. Care must be taken to clean filtration materials on a regular basis. 2. We are finding at TTPG that feeding a variety of prey items is probably much more important than previously thought. There are a number of unpublished reports and articles here at The TTPG showing that turtles fed a large quantity of a single food source, such as goldfish or commercial pellets, can quickly show signs of severe obesity such as kidney and liver problems, often leading to premature death. These detrimental conditions are also related to under-sized enclosures and other sub-optimal conditions. We suggest using a vivarium that is as big as financially and physically possibly. Additions of driftwood, stone, or even large sections of PVC pipe can be used to promote exercise and exploration - keeping captive specimens alert and active, thus helping to reduce risks associated with overfeeding and crowding. 3. Watch for any injuries to the shell, skin, and nails. These problems seem to occur in Chitra quite commonly during shipping. Damaged claws and flippers can become infected easily in the warm, wet environment of the aquatic enclosure. Damaged body parts, including shell damage, can be treated with Silvadene cream - an antibiotic cream for burns available from your local pharmacist. The turtle will need to be dried out before treatment. A box or a tub with a lid works well. A quick preliminary wash over the infected spots with a swab of warm, salty water seems to help. (Betadine and iodine-based solutions are no longer recommended by many medical institutions.) After drying, gently rub the Silvadene cream onto the infected areas. Let the turtle remain in the "treatment tub" on a cloth towel for another 4 to 5 hours. After 2 or 3 treatments over a week-long period, all infected areas begin clearing up and reinfection has not been noticed in over a dozen softshells I have treated over the past 3 to 4 years. Keeping several handfuls of aquarium salt per gallon of freshwater in enclosures will also help keep softshells in prime condition. (Saline conditions produce environments that restrict the growth of bacteria.) BREEDING Due to the large size of breeding age Chitra , and therefore the large enclosure required, very few private turtle keepers have the facilities to keep and breed Chitra indica . Difficulties have been experienced in trying to observe Chitra in the wild, and so only a few anecdotal stories exist of breeding or courtship behavior. These difficulties include poor visibility in the large, slow-moving rivers in which they are found. There have recently been importations of farm-raised Chitra from a turtle farm in Malaysia. I am very excited by the fact that there are now available specimens of this exciting yet aggressive wonder of the turtle world. Chitra indica is a fascinating and mysterious creature. Although known to science for over 150 years, incredibly little is known of its behavior and lifestyle. Hopefully, as the knowledge and advances in keeping turtles in captivity reaches new sophistication, we will one day be able to experience the incredible sight of Chitra hatchlings swimming in the pools of our breeding facility. REFERENCES Ernst, C. H. and Barbour, R. W. (1989) Turtles of the World, USA: Smithsonian Pritchard, P. (1979) The Encyclopedia of Turtles and Tortoises. TFH. Wirot, N. (1979) The Turtles of Thailand. Siamfarm Zool. Gard. 222 pp.
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