Turtle Survey of Prey Long, Cambodia
4-16 MAY 2007
BY SITHA SOM, YOEUNG SUN, SOKHORN KHENG, CHAMNAN KIM
Prey Long contains many streams which flow into the Mekong River, as well as permanent and temporary standing wetlands (ponds and marshes). In addition, there are large areas of flooded forest. These freshwater habitats provide ideal conditions for several of Asia?s globally threatened freshwater turtles. In addition, the deciduous dipterocarp forests provide suitable habitat for one of Cambodia?s most endangered tortoises, the Elongated Tortoise. Our aim was to assess the current species composition, distribution, relative abundance, and threats to tortoises and freshwater turtles in Prey Long, and to review the conservation importance of the area for turtles.
We used two methods to survey for turtles - timed searches and live-trapping. Timed searches were carried out during the day and at night. During these timed searches we walked though areas of suitable habitat, looking for turtles in good locations (e.g., under vegetation, alongside streams, in marshes). We timed the search and recorded the number of observers so that we could work out the number of turtles found per person-hour. This allows us to compare between sites.
Live-capture traps were used to assess the composition of turtle populations. Nine traps measuring 70cm long, 50cm wide and 30cm high were used. Trapping was conducted for seven nights. Traps were placed in suitable microhabitats in shallow water with part of each trap above the water surface, allowing trapped turtles to breathe. We chose baits for the turtle traps that were strong smelling to attract turtles. We used meat and fruit to attract turtle species with different diets. Bait used included chicken, fish, durian, prohok (a paste made from fermented fish), jackfruit, coconut, pineapple, and banana.
We captured three turtles during timed searches and observed seven turtles in the possession of local hunters during the course of this survey, but no turtles were captured in traps. In total, the 2005 and 2007 surveys together documented five of these species in the wild or in the presence of hunters within the forest. The presence of a sixth species, Pelochelys cantorii, was confirmed in the Mekong River during a CI- and WWF-funded river turtle study in February 2007. The last two species, the Black Marsh Turtle Siebenrockiella crassicollis and the Yellow-headed Temple turtle Hieremys annandalii were only documented from anecdotal evidence, so their presence in Prey Long still needs to be confirmed. The wetland habitats within Prey Long are also ideal for the Malayan Snail-eating Turtle Malayemys subtrijuga, although this species was not recorded in our surveys or interviews.
Table 1. Turtles reported from Prey Long from preliminary surveys in 2005 and more extensive interviews and surveys in 2007
Threats to Turtles
Many people in this area catch turtles to sell to wildlife traders who reportedly live in Kratie province. Interviewees indicated that a significant proportion of the turtles collected in Prey Long are smuggled to Vietnam. This matches turtle trade information collected in other parts of Cambodia (Som et al. 2005). According to interviewees, many of the turtle collectors were reported to come from Sandan District in Kampong Thom province. During the survey, we met three turtle hunters with four hunting dogs and all were from Sandan district. These hunters reported that middle-men at their village would buy turtles from them. Depending on species and weight, the turtles they caught fetched between US$1-10/kg. The hunters had seven turtles in their baskets, consisting of one Giant Asian Pond Turtle (Heosemys grandis), three Asian Leaf Turtles (Cyclemys cf. tcheponensis), and three Asiatic Softshell Turtles (Amyda cartilaginea).