140 



Fishery Bulletin 93(1), 1995 



kempi, and green turtles (Henwood and Ogren, 1987) 

 captured in the vicinity of Cape Canaveral. In addi- 

 tion, the results of research conducted in response 

 to incidental mortality of marine turtles due to dredg- 

 ing in the Port Canaveral ship channel were pre- 

 sented at the Cape Canaveral Sea Turtle Workshop 

 (Witzell, 1987). 



In 1986, the NMFS Panama City Laboratory initi- 

 ated long-term studies of marine turtles found along 

 the northwest (Cedar Keys) and east-central (Cape 

 Canaveral) coasts of Florida (Schmid and Ogren, 1990). 

 The Kemp's ridley turtle was the target species in both 

 study areas. This paper presents the results of NMFS 

 marine turtle studies conducted in nearshore waters 

 of east-central Florida from 1986 to 1991. Information 

 concerning marine turtle species composition, relative 

 abundance, size frequency, seasonal occurrence, move- 

 ments, morphometries, and growth is provided. 



Materials and methods 



Data collection 



A commercial shrimp-fishing vessel was contracted 

 by NMFS, from May 1986 to December 1991, to mea- 

 sure, tag, and release marine turtles incidentally 

 captured during trawling. Fishing effort 

 and location were a function of the sea- 

 sonal abundance of brown shrimp, 

 Penaeus aztecus, and white shrimp, 

 Penaeus setiferus. Trawling was con- 

 ducted between St. Mary's Entrance, 

 30°43'N, and Sebastian Inlet, 27°52'N 

 (Fig. 1), and was concentrated in the 

 Cape Canaveral area, 28°30'N to 28°15'N, 

 as defined by Henwood ( 1987a). Fishing 

 effort did not extend beyond 24 km off- 

 shore and 25.6 m in depth. The majority 

 of effort occurred less than 8 km offshore 

 and 13.4 m in depth. Trawling gear con- 

 sisted of four 12.2-m or 12.8-m nets (two 

 on each side) for targeting brown shrimp, 

 or two 24.4-m nets (one on each side) for 

 targeting white shrimp. 



Captured turtles were double tagged 

 on the trailing edge of the fore flippers 

 with #681 Inconel cattle ear tags. Tag- 

 ging information for each turtle included: 

 tag codes, species, date, location of cap- 

 ture, latitude and longitude, depth, gear 

 type, standard straight-line carapace 

 length (SSCL; nuchal notch to posterior 

 end of postcentral), and straight-line 

 carapace width. Carapace length and 



width were measured to the nearest 0.1 inch with 

 forester's calipers and were converted to metric units 

 for analysis. Kemp's ridley and green turtles were 

 weighed with a 15-kg capacity spring scale. Notes 

 on the condition of the turtle were recorded when 

 the animal was injured or deformed (e.g. missing flip- 

 per, carapace wounds, etc.). 



NMFS issued Sea Turtle Conservation Regulations 

 on 29 June 1987 (Federal Register, 1987) that re- 

 quired vessels 25 feet (7.6 m) long or longer to use 

 Turtle Excluder Devices (TED's) in the Cape 

 Canaveral area beginning 1 October 1987. Subse- 

 quently, a NMFS permit was issued authorizing the 

 contract vessel to conduct a TED testing program 

 during fishing operations. The testing procedure con- 

 sisted of towing a net(s) equipped with a Morrison 

 soft TED on one side of the boat and a net(s) without a 

 TED on the other side. Pounds of shrimp, marine turtle 

 captures, and total catch (when possible) were recorded 

 for the trawl types. Effort data were available for 1989- 

 91, including trawl size and type, number of tows and 

 total tow time, and number of days fished. 



Data analysis 



The terms "juvenile" and "subadult" used to describe 

 the early stages of the marine turtle life history are 



St Mary's Entrance 



: Cape Canaveral 



Sebastian Inlet 



Figure 1 



Sampling areas for marine turtles (Caretta caretta, Lepidochelys kempi, 

 and Chelonia mydas) off the Atlantic coast of Florida from 1986 to 1991. 



