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Wrapping up the Leatherbacks
and Starting with the Greens
The first leatherback hatchling tracks of the season.
| The leatherback nests we marked in late March have now started to hatch out and the last week we excavated the first nests of the season. The first three nests that hatched out had a good hatching success, around 65%, in spite of having been washed over by the tide. The fourth nest though had a very low success, only 8% of the eggs had hatched. Over the next couple of weeks we will excavate more of the nests and we should soon have a better idea of how good the overall hatching success has been for this year's leatherback nests.
One of the more exciting events in the last couple of weeks was a loggerhead encounter we recorded in late May. Loggerhead turtles generally nest on more subtropical beaches and they are rarely encountered in Tortuguero. In fact, the last encounters before this was in May of 1998, some three years ago. Catalina, the Field Coordinator, spotted the loggerhead and called the other tagging team by radio so that everyone could get a chance so see the uncommon sighting. The loggerhead halfheartedly began to dig a body pit but decided to abort and returned to the water without laying. It was tagged and if we are lucky, the tag or the tag number will one day be sent back to us by someone who has seen the loggerhead somewhere else in the Caribbean (or beyond).
Over the last couple of weeks we have also tagged three hawksbill turtles. Two of the hawksbill nests may have been poached which is unfortunate as hawksbills are considered critically endangered and every nests count. In previous years, beach patrols have generally not been conducted in late May-early June and it may be that this period is relatively important in terms of hawksbill nesting.
Tracks from a big cat and a smaller cat.
| We also counted additional hawksbill nests during the track surveys. In addition to the turtle tracks there were also plenty of tracks from jaguars in the beach sand. One of the jaguars appeared to have been walking along the beach for several miles, in search of turtles. It had walked on the mid-beach platform and every time it came across a turtle track, fresh or old, it had followed it up towards the vegetation to see if the turtle was still there. I could see the jaguar tracks continuing like this until the jaguar had come up on a green turtle that was still on the beach. From the tracks it looked like the jaguar had jumped on the green turtle and that the turtle in an effort to escape had try to get out of the hole it had created during the camouflage. This may have helped the jaguar as the turtle may have reared up and it that way allowing the jaguar to flip it over backwards. The characteristic track of an upside down turtle showed that the jaguar had dragged the turtle into the vegetation. The carcass was leaning against the trunk of a sea grape plant and the severed neck of the turtle was hanging to one side. When I returned three days later, the jaguar had dragged the dead turtle further into the vegetation and had eaten parts of the neck muscles.
There must be more than one jaguar on the beach because along some sections of beach there were large jaguar tracks leading in one direction and smaller tracks in the opposite direction. Maybe the green turtles make for a good diet and allow the jaguars to increase in numbers?
The end of the Leatherback Program sees the start of the Green Turtle Program and this year the Green Turtle season was officially opened a month earlier than previous years. This means a further increase in park ranger patrols and it has already paid off in the arrest of several poachers.
CCC National Director Roxana Silman hands over a computer donated by the Institute of Earth and Man, to the Tortuguero school at the inauguration of the 2001 Green Turtle Season.
| The official inauguration of the green turtle season took place at the park ranger station in Tortuguero and dignitaries from diverse institutions took part in the event. There were Don Beto, the president of the Tortuguero Development Association, Claudio Pacheco, the head of the Costa Rican Coast Guard and of course everybody from the Tortuguero Conservation Area. The Tortuguero school and high school also took part in the event and CCC took the opportunity to donate a computer to the Tortuguero school. The computer was donated by the Institute for Earth and Man, located in Dallas, Texas and will be a useful tool that will allow Tortuguero school children to keep up with the rapid changes in technology occurring in Costa Rica.
Although Tortuguero may be geographically isolated it is well connected with the rest of the world. A proof of this is the large number of visitors from all over the world that come to Tortuguero to see the nesting sea turtles. We thank those who came to see the nesting leatherback turtles this year and look forward to the visitors that will come to watch nesting green turtles in the coming months.
Hasta Pronto,
Sebastian Troëng
Research Coordinator
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