Trident Submarine Basin

Project Type(s):capture

Site Name:Trident Submarine Basin

Site Reference Number:35

Region(s):Southeast

Counties:Brevard

Approximate Latitude: 28.41 Approximate Longitude: -80.6

Principal Investigator(s):Bagley, Dean; Ehrhart, Llewellyn; Nelson, David; Redfoot, William

Point(s) of Contact:Bagley, Dean - Phone Number: (407) 765-5250, Email: de315786@pegasus.cc.ucf.edu

Organizations Involved:University of Central Florida, United States Army Corps of Engineers - Vicksburg

Organization Type(s):university, federal agency

Project Status: Active

Start Date: 1993

End Date: n/a

General Method(s) Used:dip net, set net

	Visual	Capture
Sampling regime:	annually	annually
Measure of effort:	unknown	cap/area

Bottom Type(s):algae mat, rock wall

Water Type Zone: neritic Water Type Environment: marine

Min. Depth (m): 0 Max. Depth (m): 12

Mean Depth (m): 12

Species	No. of Captures	No. of Sightings	Min Size* (cm)	Max Size* (cm)	Mean Size* (cm)	FP Observed	Life Stages**	Comments
Green Turtle (Cm)	1438	n/a	21.5	52.0	31.9	No	n/r
Loggerhead (Cc)	10	n/a	54.2	70.8	61.7	No	n/r
Kemp's Ridley (Lk)	0	n/a	0.0	0.0	0.0	n/a	n/a
Hawksbill (Ei)	0	n/a	0.0	0.0	0.0	n/a	n/a
Leatherback (Dc)	0	n/a	0.0	0.0	0.0	n/a	n/a

*All size measurements are SSCL unless otherwise indicated
** For Cm, Cc, Lk, & Ei: O - Oceanic-stage juvenile; N - Neritic-stage juvenile; S - Subadult; A - Adult. For Dc: I - Immature; A - Adult. n/a = not applicable; n/r = not reported.

diet

growth rates

radio tracking

sonic tracking

vitamin levels

The Trident Basin is a man-made embayment lined with rock rip-rap, which is covered by an algal mat. The site is home to a significant number of juvenile green turtles, which contrasts with the predominance of loggerheads in the adjacent ship channel. Very few loggerheads are ever found in the basin, and most of those are sick and have to be taken to rehabilitation facilities. The small size of green turtles in the basin is remarkable in that none is larger than 50 cm. Most other projects in the state capturing juvenile green turtles find individuals greater than 50 cm. This population structure might be explained by the limited biomass of the algal mat in the basin. Diet analysis shows that the turtles mainly eat the algae that grow on the rip-rap. David Nelson used radio and sonic telemetry on some of the green turtles captured to determine movements and diving patterns. Turtles spent a majority of time near the rocky shoreline on the western side of the basin, which provides cover and feeding habitat. Some turtles moved out of and then back into the basin during predawn hours. Daytime dives were shorter and more frequent than those at night, suggesting that the turtles feed during the day and rest at night. The sex ratio in this project is strongly biased towards females, and FP has not been found on turtles in the basin.

File Name	Type	Description
Hirama_etal_2014.pdf	Journal Article
Kubis_etal_2009.pdf	Journal Article

* This document is available from FWC by request. Email SeaTurtleData@MyFWC.com if you would like a copy. Please include both the project name and file name in your email.
** This document has been provided to FWC but is unavailable for download. Please contact the project PI if you would like a copy.

Hirama, Shigetomo and Llewellyn M. Ehrhart. 2007. Description, prevalence and severity of green turtle fibropapillomatosis in three developmental habitats of the east coast of Florida. Florida Scientist 70(4): 435-448.

Kubis, Stacy, Milani Chaloupka, Llewellyn Ehrhart, Michael Bresette. 2009. Growth rates of juvenile green turtles, Chelonia mydas from three ecologically distinct foraging habitats along the east central coast of Florida, USA. MEPS, 389:257-269.

Redfoot, W., and L. Ehrhart. 2013. Trends in Size Class Distribution, Recaptures, and Abundance of Juvenile Green Turtles (Chelonia mydas) Utilizing a Rock Riprap Lined Embayment at Port Canaveral, Florida, USA, as Developmental Habitat. CCB 12:252–261.

Hirama, Shigetomo, L. Ehrhart, L Rea, R. Kiltie. 2014. Relating fibropapilloma tumor severity to blood parameters in green turtles Chelonia mydas. Dis. Aquat. Org. 111:61–68.