Marine Turtle Research 2016

TMORowell Alarcon

(c) Rowell Alarcon/TMO

The team of TMO researchers, marine park rangers, WWF-Philippines, and partners recently concluded a three-day marine turtle monitoring trip to the Tubbataha Reefs Natural Park.  The activity was conducted in partnership with the Marine Research Foundation, headed by its Executive Director, Dr. Nicolas Pilcher.  Since 2010, Dr. Pilcher has trained TMO staff and partners in the rodeo method, carapace measurement, tagging, laparoscopy, and tissue sampling of turtles for DNA analysis.  This year, along with Dr. Rizza Salinas of DENR-BMB, who has been part of the turtle research since 2010, the team was joined by Mr. Borgenius Shalah, marine biologist of the Puerto Princesa Underground River.

2 TMO ROwell Alarcon

(c) Rowell Alarcon/TMO

A total of 200 green sea turtles (Chelonia mydas) were captured using the rodeo method.   This involves a team jumpers and a boat tender chasing a turtle.  A jumper dives for the turtle in the water, and, if unsuccessful, is followed by another jumper until the turtle is captured.

3. turtle tagging

(c) Rowell Alarcon/TMO

These turtles were then measured and checked for tags.  TRNP Inconel tags were placed on untagged turtles and lost tags replaced.  Data was recorded and added to the TRNP database on sea turtles.

4 TMO Rowell Alarcon copy

(c) Rowell Alarcon/TMO

Laparoscopy, a minor surgical procedure, was also performed to determine the age class, gender, and the reproductive stage of the sea turtles.  Tissue samples for DNA analysis were taken from 100 turtles this year to help define the relationship of the TRNP sea turtle population to others found elsewhere in the world.

5. tubbataha turtle tagging

(c) Rowell Alarcon/TMO

During laparoscopy, two untagged male turtles were found to be ready to breed this year.  As attempts to capture nesters for tagging have failed, Dr. Pilcher decided to fix satellite trackers on these adult males instead.  The tag will provide information on the range these turtles, that normally do not stay long at the park.   Dr. Pilcher noted that these are probably the only male green sea turtles with satellite trackers in the Southeast Asian region.  Satellite trackers previously deployed in the region have been on nesters (females) which were conveniently caught on land as they laid eggs.

6 tommy-schultz_com-82 copy


Another major highlight of the trip was the recapture of 49 previously tagged turtles.  One of these apparently came from Malaysia (left: MYS27963; right: MYS27964).  This is the first time that a foreign tagged turtle has been documented in the park.  This nester from Malaysia measured 99 cm and was the largest caught this year.  Recapture data account for significant information on habitat range and distribution as well as growth rate, among others.

This trip was funded by the Marine Research Foundation based in Sabah, Malaysia.