WWW.WAS.ORG • WORLD AQUACULTURE • JUNE 2015 61 (CONTINUED ON PAGE 62) following states of India: West Bengal, Andhra Pradesh, Odisha, Bihar, Uttar Pradesh, Kerala and Maharashtra. However, fishing of freshwater turtle is not an organized and regular activity. Commercially these species of turtles are caught by gill nets, hooks or by hand, with burrowed turtles located by probing with an irontipped bamboo stick. Prolonged drought may increases predatory pressure on freshwater turtle populations in local ponds (Bhupathy and Vijayan 1989). Problems Caused by Turtles in Freshwater Aquaculture Disease carriers/ vectors. Leeches and mites are often found on freshwater turtles in the wild. In turtles, mites are associated with mechanical transmission of Aeromonas hydrophila and other bacterial pathogens, rickettsial agents and viruses. Generally leeches are found on the legs, head, neck and oral cavity of turtles. All turtles are also potential carriers of pathogenic bacteria such as Salmonella sp., Streptococcus sp. Indian flapshell turtles are carriers of Mycobacterium ulcerans that causes Mycobacteriosis in turtles and painless ulcers, known as Buruli ulcers, in humans (Sakaguchi et al. 2011). Fish may concentrate M. ulcerans in gills and intestines, acquired from water sources or from amphibians such as frog and turtles and serve as passive reservoirs of the bacterium. Turtles frequently have cutaneous myiasis. Bot flies (including Cuterebra spp.) create a cutaneous wound in which to lay their eggs, which hatch into bots that live in their cyst-like structures until they are mature enough to leave the wound. The most common types of worms found in turtles are the red nematode worm and the white roundworm. Eimeria spp. are apicomplexan parasites that are capable of causing the disease coccidiosis in carnivorous feeder that consumes mainly small molluscs, annelids, freshwater larval crabs, insects, tadpoles, dead animal matter, earthworms, smallsized fishes and larvae of different fishes. It also feeds on aquatic plants such as grass, water lilies, bladderwort and some seeds and fruits (Tikader and Sharma 1985). This turtle species consumes about 0.5 percent of body weight daily in natural habitat but, in captivity, is about 8 percent of body weight daily (Hossain et al. 2012). Burrowing ambush behavior helps these turtles catch live fishes in ponds (Das 1991). During summer, when ponds were drying, dead or dying fishes were consumed by this species of turtle (Bhupathy and Vijayan 1993). Indian flapshell turtle can survive drought by aestivating on land for a long time without feed (Bhupathy et al. 2014). Aestivation sites are generally the area with thick grass or forested areas where turtles can bury to a depth of 3-6 cm from the land surface (Auffenberg 1981). Reproduction Males are smaller at maturity than females; turtles with a carapace length of >160 mm in males and >170 mm in females are mature (Yadava and Prasad 1982). The egg-laying period of the flapshell turtle is generally between August and March. During this period, a gravid female turtle can lay eggs in three clutches, with each clutch containing13-15 eggs. The incubation period range is between 119 and 225 days. Hatching success is around 4550 percent. Maximum numbers of hatchlings appear during June (Hossain et al. 2010). A single female turtle can lay 40-50 eggs and 20-30 young can emerge from those eggs in a year. Commercial Exploitation Indian flapshell turtle is considered to be a food-grade freshwater turtle and is commercially exploited from the TOP, FIGURE 2. Setting up of net for catching the turtles. BOTTOM, FIGURE 3. Haul of freshwater turtles from a farm site
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