DCNA Satellite Tracking Project on St Eustatius and St Maarten
author: Dr Emma Harrison
In collaboration with the Dutch Caribbean Nature Alliance (DCNA) and the
Nature Foundation Sint Maarten, St Eustatius National Parks (STENAPA) has
initiated a satellite tracking study of its nesting green and hawksbill
turtles. To date, nothing is known about where these animals go once they
leave Statia; this project aims to track the turtles as they migrate from
the nesting beach to their foraging grounds, as it is known that they do not
stay around Statia once the nesting season ends. Learning their movement
patterns gives us a clearer picture of their geographical range and so
allows us to improve protection and conservation efforts, not just on the
nesting beaches, but also in other vital habitats. Satellite tracking also
identifies migration pathways; by knowing these we can determine any
potential threats, such as fisheries interactions, turtles may face en route
between foraging and nesting areas.
Under the supervision of Dr Robert Van Dam, a sea turtle biologist with many
years of experience using satellite telemetry to track turtles in the
Caribbean, transmitters will be attached to three females on St Eustatius
and two individuals on Sint Maarten.
As part of the on-going Sea Turtle Conservation Programme on the island,
daily track surveys and nightly patrols are conducted on the principal
nesting beach, Zeelandia; all nests are recorded and any individuals are
tagged and measured. Data from these surveys were used to predict when
turtles would return to the beach, thus maximising the chance of finding a
turtle.
On 20th September the night patrol encountered a female green turtle and
successfully attached a transmitter, despite adverse weather conditions
severely hampering their efforts. She was a very large turtle, measuring
113.1cm Curved Carapace Length, who had been observed nesting on three
previous occasions, the first of which was 19th August, when she was tagged.
Another important aspect of this project is the opportunity to educate the
public about turtle conservation issues by showcasing turtles’ migratory
behaviour. A competition was organised prior to the start of the project
for students at all the island schools. Entrants had to either draw a
turtle, depicting where she may go during her migration; write an essay
about her journey; or, create a model using recyclable materials. Over 100
entries were received, from students of all ages. Winners from each
category were given the opportunity to name one of the tracked turtles, as
well as receiving a certificate, a free subscription to STENAPA’s Snorkel
Club, a t-shirt and a boat tour of the island.
The first turtle to be tracked was given the name “Miss Shellie”; this was
the choice of Krystell Statie, Grade 7, from the Statia Terminal School, who
won the model category. The other winners were Evan Hassell, Class 3,
Governor De Graff School, for his picture of “Lisa”, and Naomi Smith, Grade
4, Homeschool, for her story about “Grace”.
“Miss Shellie” can be viewed on-line by visiting the STENAPA website at
www.statiapark.org, where links to a map showing her most recent location
can be viewed. Following her release with her transmitter she remained in
Statia waters for 11 days before coming back to nest for a fifth time.
While researchers initially thought this was her last nest of the season her
behaviour since has been a little unclear. She remained in the general
vicinity of the island, giving the indication that she was going to nest
again, however, her most recent location is approximately 25km off the
nesting beach on the Atlantic coast, so she may finally be heading off on
her migration. It seems as if we may just have to wait for the next few
days, when she would be expected back, to see if she turns up on the beach
again.
It is hoped that two more turtles will be encountered in the next week or
so, before the nesting season finishes here on St Eustatius at the end of
this month. Several turtles that were seen earlier in the season are
potentially still in the area and may return to the beach to nest again
before leaving. On Sint Maarten, researchers are expecting a hawksbill
turtle this weekend; one nested approximately two weeks ago, and so is due
to return within the next couple of days. |
