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Since 1977, the Marine Extension Service has been working with shrimpers to develop and test devices to allow turtles to escape from shrimp trawls. These Turtle Excluder Devices are called TEDs. All legal TEDs have been tested in the wild aboard the R/V Georgia Bulldog.
In 2007, MAREX faculty and staff brought Georgia Sinkey Boone, a Georgia shrimper and net designer, to the International Sea Turtle Symposium as a co-presenter.
Sinkey invented the first excluder device
in 1968 to keep cannon ball jellyfish
out of his nets.
Sinkey tells the story of his invention in the poster he presented. Download Poster (pdf.)
Cape Canaveral Sea Turtle Research
During 2006 and 2007, the South Carolina Department of Natural Resources (SCDNR) and the University of Georgia's Marine Extension Service (MAREX) partnered to study the reproductive biology and seasonal distribution patterns of adult male loggerheads.
Using modified shrimp trawl nets known as “turtle nets” (i.e., no turtle excluder device and larger mesh to minimize by-catch), short-duration (15 min) drags were conducted aboard the R/V Georgia Bulldog in the shipping entrance channel of Port Canaveral, FL.
Sampling was completed in April in both years, the time of year with the greatest probability of collecting adult male loggerheads in this shipping entrance channel.
This recent work was novel in several respects. First, most of the adult male loggerheads collected in this study were satellite-tagged to document their local distributional patterns during the mating season, as well as to determine the locations and water depths where this very elusive component of loggerhead populations along the U.S. East Coast spend the remainder of the year.
Because healthy adult male loggerheads are rarely seen in the wild, very little is known about their distributional habits.
During the study, researchers collaborated to gain as much information
from the loggerheads before they were released. A vet student learns
how to collect a scute scraping (left photo) and a member of the research crew
removes a biopsy plug (middle photo), which will both be analyzed for contaminants.
Blood samples were also taken (right photo). Among other analyses, blood tests conducted aboard the vessel confirmed which animals were healthy enough to participate in the study.
A vet student learns how to collect a scute scraping (l eft photo, below ) and a member of the research crew removes a biopsy plug ( right photo, below )…
 
In addition to laparoscopic examination to characterize reproductive activity of individual male turtles prior to attachment of satellite-transmitters, an additional non-invasive reproductive technique was also utilized: ultrasound. Although ultrasound can not provide some data that is possible with invasive laparoscopy, by comparing ultrasound and laparoscopic images for a large sample size of adult male loggerheads, researchers hope to be able to validate this non- invasive technique for characterizing many reproductive aspects of sea turtles in the future.
 
In total, 38 individual adult male loggerheads were collected and sampled during the 15 sea days in this study, of which 29 were satellite-tagged. Reproductive data for nearly all adult male loggerheads collected indicated that they were actively mating with adult female loggerheads in the vicinity. However, satellite-telemetry data revealed that some of these reproductively-active turtles were migratory, while others were long-term residents. The migratory group remained  close to shore during April and May before quickly emigrating away from Canaveral by the end of May, while the resident group shifted to the deep waters of the continental shelf offshore of Canaveral at about the same time that the migratory animals also left the area. Migratory animals dispersed along the U.S. East Coast and into the Gulf of Mexico to a number of different areas ranging from the New Jersey to the Florida Keys and Florida Panhandle, encompassing nearly the entire extent of nesting range for loggerhead sea turtles in North America.
This sea turtle research fostered many unique partnerships. Researchers, managers, veterinarians, students, extension agents, and local seafood market owners all joined forces to complete this valuable study.
SCDNR and MAREX wish to thank
Wild Ocean Seafood Market for their help and
hospitality, and for their commitment to conservation research.
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