As part of our Setiu River Terrapin Recovery Project, head-started river terrapins that have been equipped with microchips for individual identification are released into the Setiu River at one to three years of age. In order to monitor their progress in the river, the terrapins have to be recaptured, weighed and measured for increments in body weight and carapace (shell) length at regular intervals of time.
Initially, large-meshed gill nets were used to recapture the terrapins, but this method yielded very few individuals for analysis. In January 2009, we enlisted local fishermen to help us obtain terrapins encountereed in the course of their fishing activities. A reward of RM10 is given for each terrapin surrendered. In the first nine months of this study, a total of 66 head-started terrapins have been recovered, enabling us to come to some preliminary conclusions on the performance of the head-started terrapins in the wild. The terrapins were caught on hooks and gill nets, but fortunately, the fishermen were able to free them alive. Our data is summarised in the following paragraphs:
Terrapins hatched in 2004 and released in 2005, 2006 and 2007, averaged 4031g in body weight and 301mm carapace length (CL) when recaptured in 2009, demonstrating an average increase of 3121g in weight and 113mm in CL in the wild.
Terrapins hatched in 2005 and released in 2007 and 2008 averaged 2811g in weight and 267mm in CL when recaptured in 2009, showing average gains of 969g in weight and 33mm in CL in the wild.
For terrapins hatched in 2006 and released in 2009, recaptures were made after a lapse of two to four months of growth in the wild. These three year-old terrapins had average weights of 2015 g and CL of 235mm and registered average weight gains of 229g and CL gains of 8mm.
This preliminary data demonstrates the ability of head-started river terrapins to survive, grow and adapt to natural food when released into the wild. The pictures below show some of the work being done during the analysis of the terrapins caught by fishermen.
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Taking a terrapin from a cage made to hold terrapins surrended by fishermen for analaysis
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Close-up of the cage
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Terrapins obtained for analysis
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Paying a fisherman for the terrapin he just surrended for analysis
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Line-up of paraphernalia used for analysing the terrapins
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Scanning a terrapin for its microchip number
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Willing helping hands of the local fishermen
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Everyone happily helping out
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Pak Nor, the oldest fisherman in Setiu is keen to help as well
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With Ropi, our reliable fisherman friend who helps collect the captured terrapins from the fishermen
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The two project executants busy at work
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Pelf and Chong Leng measuring a terrapin
