The Burmese roofed turtle (Batagur trivittata) is a critically endangered endemic species known only from the Ayeyarwady, Chindwin, Sitaung, and lower Salween rivers, where it was historically reported to be common. However, rampant egg collection, conversion of nesting beaches to seasonal agricultural fields, and chronic over-harvesting of adults by fishermen led to long-term population declines, and by the 1970s the Burmese roofed turtle was assumed to be extinct.
Fears of extinction fortunately proved premature, and the species was “rediscovered” in Dokthawady River (a tributary of the Ayeyarwady River) during a 2001 WCS expedition (Platt et al., 2005). Subsequent surveys located additional turtles along the Dokthawady River and in temple ponds in Mandalay, and a remnant breeding population was found in the upper Chindwin River (Kuchling, 2002). Unfortunately the Dokthawady population is now thought to be extinct after the construction of a hydropower dam allowed an influx of fishermen and inundated nesting beaches. However, turtles obtained from the river and temple ponds in Mandalay were used to found a captive assurance colony at the Yadanabon Zoological Gardens in Mandalay.
To address continuing declines among the remaining wild population of Burmese roofed turtles, WCS/TSA implemented an aggressive in-situ conservation program along the upper Chindwin River. This program is based at Limpha Village and consists of 1) protection and monitoring of nesting beaches by locally hired “conservation wardens”, 2) collection and transport of eggs to a protected beach for incubation, 3) head-starting of hatchling turtles, and 4) an education campaign targeting riverside agricultural communities. This integrated conservation program has enjoyed noteworthy success and as of 2015, over 700 roofed turtles have been hatched and reared successfully as part of the head-starting program. Nonetheless, fewer than 10 females remain in the wild, and given the extinction risk inherent in any small population, this aggressive conservation program must be continued if this population is to survive.
In addition to conservation efforts along the upper Chindwin River, three assurance colonies have been established with the objective of bolstering the global population of Burmese roofed turtles and producing offspring for eventual release into the wild. The initial assurance colony was founded at the Yadanabon Zoological Gardens (Mandalay) and currently contains 22 adult breeding turtles. The founding stock consists of turtles confiscated by the Myanmar Forest Department after being illegally taken by fishermen, and others found in monastery ponds and donated to the zoo for conservation purposes. The turtles are housed in a spacious natural pond and provided with an artificial sandbank for nesting.
The 2014-15 nesting season yielded 53 hatchling turtles, now being head-started at a specially designed rearing facility in the zoo. In 2010, a second assurance colony was established at Lawkanandar Wildlife Sanctuary using captive-bred progeny produced at the Yadanabon Zoo as well as turtles hatched on the upper Chindwin River. Most of the 100 roofed turtles in this assurance colony are now 9-10 years-old and have yet to reach sexual maturity. However, adult males now exhibit breeding coloration and reproduction is expected within the next few years. In anticipation of future breeding, a large artificial sandbank for nesting turtles was constructed in the enclosure during 2015. The third assurance colony consists of another 100 turtles housed in a large pond near the headquarters of Htamanthi Wildlife Sanctuary in the riverside hamlet of Htamanthi. These turtles were originally hatched on the upper Chindwin River, head-started at the Yadanabon Zoo, and returned to Htamanthi in 2015. Breeding is not expected to begin for another 3-5 years.
Given this numerical buffer against biological extinction, the first reintroduction of head-started roofed turtles to the wild was undertaken in 2015. Prior to this action, a wide-ranging assessment of potential release sites was conducted. Ultimately, two areas were identified where reintroduction was thought likely to succeed. The first area is a stretch of the upper Chindwin River near Limpha Village, already inhabited by several nesting females, while the second is along Nam Thalet Chaung, a relatively pristine tributary of the Chindwin that debouches into the river near Htamanthi.
In January 2015, 160 large sub-adult roofed turtles were transported by truck from Mandalay to the WCS/TSA Forward Operating Base in Limpha Village; 60 of these turtles were destined for release while the remaining 100 would go to the nascent assurance colony being established in Htamanthi. The trip proved nightmarish, a week-long truck ride along rutted jungle tracks awash in mud, followed by a 160 km boat trip up the Chindwin River. Upon arriving at Limpha the turtles were released into two large concrete grow-out ponds to recuperate from their arduous journey.
In the meantime, “soft-release” acclimation pens were constructed at two sites along the Chindwin River and Nam Thalet Chaung. Given that few reintroductions of river turtles have been attempted anywhere, there was almost nothing in the scientific literature to guide these efforts. Therefore the release was designed as a simple experiment to test the efficacy of penning in dampening post-release dispersal – two groups of 30 turtles would be released at each site; one group would be released immediately and the other group was penned for 30 days before being set free. The post-release movements of these turtles (monitored with VHF radio transmitters) would then be compared to determine if penning periods had any effect on dispersal patterns.
Release ceremonies attended by government officials and villagers were held first at Limpha and later on a beach along Nam Thalet Chaung. The turtles were ceremonially “donated” to attending Buddhist monks who then blessed them before they were either released into the river or placed in a holding pen. In late March of 2015 the pens were opened and the turtles released. On both the Chindwin River and Nam Thalet Chaung most turtles moved only 1-2 km up- or downstream from the release site, many taking up residence in deep holes that according to local lore, once harbored resident roofed turtles. Wet season movements proved more extensive and surging floodwaters appeared to have moved several turtles many kilometers from the release sites. Monitoring is currently underway to determine if the reintroduced turtles will continue to range widely or return to the release areas. Additional releases of head-started roofed turtles are scheduled for the dry season of 2016.
As part of the conservation effort to restore roofed turtles to the wild, WCS/TSA has leased the fishing rights to approximately 5 km of the Chindwin River at Limpha Village. Leasing fishing rights allows us to legally control access and dictate the type of fishing gear (if any) deployed on this stretch of river with obvious benefits for turtle conservation. Furthermore, the WCS/TSA turtle conservation team in conjunction with Forest Department personnel based at Limpha conducts regular patrols of the Chindwin River to enforce laws against electro- and dynamite fishing. These patrols are generally conducted at night and enjoy considerable support among riverside communities who view fish poachers as thieves unfairly exploiting a common resource. Future plans call for leasing the fishing rights on additional sections of river to expand protection of turtles.