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ABSTRACT: The objectives of this project are to: compare current population structure (1994-1996) and distribution to baseline
data collected in 1977-1979 (Mendonça and Ehrhart, 1982), evaluate current seasonal distribution and occurrence of
sea turtles (turtles caught per net km hour or catch per-unit-effort, referred to as CPUE), and provide updated statistical
summaries of CPUE to determine regional "importance value" of this estuary.
Thirty-four sea turtles (Caretta caretta, loggerheads, and Chelonia mydas, greens) have been captured using tangle
nets in the current project (80.1 net km hours, grand CPUE of 0.42) and all but one were juveniles. Data from the
baseline project were collated from original field notes and calculation of CPUEs were made for six specific netting
sites. Calculations from baseline data indicated a total of 453 net km hours with 95 turtles captured (grand CPUE of
0.21). Greens are caught at increased rates today (CPUE=0.36) with 85% of the turtles being greens as compared to
only 21% in 1979 (CPUE was 0.04).
In contrast, loggerheads declined between the two periods with CPUEs of 0.16 in 1977-79 and 0.06 in 1994-96. A
remarkable, concomitant decline in the incidental capture of Limulus polyphemus, a primary food item for loggerheads,
has been observed. Net sets in the 1977-79 period typically included the capture of large numbers (unquantified) of
these crabs and today it is rare to see any L. polyphemus in nets set in Mosquito Lagoon. L. polyphemus have been
harvested at unknown rates in the region for use in various fisheries for bait and biomedical testing, this observed
decline warrants concern and further study.
The sex ratio was not determined in previous studies and was estimated for the current study using testosterone
radioimmunoassay for 21 turtles. A total of 94.4% of the greens were female (n=18) while 66.6% of loggerheads were
Greater than 50% of the green turtles collected in 1994-96 had the fibropapilloma virus as indicated by the presence
of tumors. Tumor size was generally small with most being less than one cm in width. These tumors were not
observed in earlier studies.
During the 1994-96 project only one green was recaptured in Mosquito Lagoon. Tumors were present on both
occasions with fewer but larger tumors noted upon second capture. We assume that many of the earlier recorded
tumors became confluent.
A green turtle with tumors was tagged and released in June 1995, and was collected in September 1996 by a fisherman
in north eastern Cuba some 2000 km away. Additionally a green turtle was captured in our nets in November 1996
that had been previously tagged (1994) by National Marine Fisheries Service in Charleston Harbor, South Carolina,
approximately 600 km north.
ANNUAL SEA TURTLE CONFERENCE; 12/1998