Dermatemys Surveys Continue in Belize

by Dr. Thomas Rainwater on April 29, 2010

On April 23rd, we conducted a spotlight survey of ~ 16 km of the Sittee River just south of Dangriga.  The locals there say turtles are in the river, but most are sliders (Trachemys) and loggerheads (Staurotypus).  They say Dermatemysare there but are seldom seen.  We saw none during our survey.

 
The following day we deployed trammel nets in a section of the river less frequented by locals and with minimal boat traffic.  No turtles were captured.  We continued netting through the night, checking the nets approximately every two hours while camping along the river bank.  Still, no turtles were captured. 

Upon pulling in the nets, we found a sizable hole in the top section of one net near the end where it was tied off.  We suspect this was the result of a crocodile becoming entangled and freeing itself.  We had seen a crocodile beneath overhanging tree limbs near that section of the net during the night.
 
On April 25, we continued north and set up operations on the Western Highway, near Monkey Bay Wildlife Sanctuary.  The following day we obtained access to Cox Lagoon, a small (~ 5 km long), relatively shallow freshwater lagoon (north of the Western Highway) flanked on both ends by deeper, narrow creeks bordered by dense forest.  In the 1990s, the lagoon was designated a crocodile sanctuary and for a some years received varying levels of protection.  Dermatemys were supposedly once abundant there, but were routinely collected by fisherman.  Steve Platt, Tony Garel, and others found Dermatemys in Cox Lagoon in the early-mid 1990s, but also found signifcant signs of harvesting (e.g., bones and shell fragments at lagoon-side camps where turtles were processed).
 
We conducted a spotlight survey around the entire lagoon and saw no turtles.  We did find one campsite where a pile of weathered turtle shell fragments, likely Dermatemys, was situated next to an old fire ring.  We have also been keeping track of the number of crocodiles encountered during turtle surveys, and this night we saw 112 crocodiles in the lagoon.  This is one of the highest densities of crocodiles we have encountered in Belize since starting surveys in the mid 1990s. 
 
Due to the crocodile-related hole in one of our nets while on the Sittee River (which we repaired) and the abundance of crocodiles in Cox Lagoon, we have decided to hold off on deploying nets in Cox Lagoon until we have surveyed most of our other targeted areas in the country.  We don't want to risk losing a net or two to crocodile damage until we have surveyed other areas (with fewer crocodiles) first.  Once the other targeted survey areas have been surveyed, we hope to return to Cox Lagoon and set the nets.

- Dr. Thomas Rainwater