Ten Thousand Islands

General Information

Project Type(s):capture, sighting

Site Name:Ten Thousand Islands

Site Reference Number:13

Region(s):Southwest

Counties:Collier

Approximate Latitude: 25.87 Approximate Longitude: -81.59

View ArcGIS map of study area

Principal Investigator(s):Schmid, Jeffrey; Witzell, Wayne

Point(s) of Contact:Witzell, Wayne - Phone Number: Not Provided, Email: wayne.witzell@noaa.gov; Schmid, Jeffrey - Phone Number: (239) 403-4225, Email: jeffs@conservancy.org

Organizations Involved:Conservancy of Southwest Florida, National Marine Fisheries Service - Miami

Organization Type(s):non-profit, federal agency

Project Status: Inactive

Start Date: 6/1997

End Date: 8/2004

Equipment and Methods

General Method(s) Used:boat survey, strike net

Sampling and Effort

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

Bottom Type(s):mud, other, oyster beds, sand, seagrass

Water Type Zone: neritic Water Type Environment: estuarine

Min. Depth (m): 0 Max. Depth (m): 4

Mean Depth (m): 1.5

Captures and Sightings Information

Species	No. of Captures	No. of Sightings	Min Size* (cm)	Max Size* (cm)	Mean Size* (cm)	FP Observed	Life Stages**
Green Turtle (Cm)	13	n/a	n/r	n/r	51.6 SCLmin	Yes	n/r
Loggerhead (Cc)	15	n/a	n/r	n/r	65.5 SCLmin	Yes	n/r
Kemp's Ridley (Lk)	191	n/a	21.4 SCLmin	65.2 SCLmin	40.4 SCLmin	No	O, N, S, A
Hawksbill (Ei)	5	n/a	52.2 SCLmin	64.6 SCLmin	57.7 SCLmin	No	N
Leatherback (Dc)	0	n/a	n/a	n/a	n/a	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.

This report adheres to the following size ranges for life stage classification for these species:

	Green turtle	Loggerhead	Kemp's ridley	Hawksbill
Oceanic-stage juvenile	< 25 cm SCL	< 30 cm SCL	< 25 cm SCL	< 25 cm SCL
Neritic-stage juvenile	25-69 cm SCL	30-69 cm SCL	25-39 cm SCL	25-64 cm SCL
Subadult	70-84 cm SCL	70-79 cm SCL	40-59 cm SCL	65-74 cm SCL
Adult	≥ 85 cm SCL	≥ 80 cm SCL	≥ 60 cm SCL	≥ 75 cm SCL

	Leatherback
Immature	< 135 cm OCL
Adult	≥ 135 cm OCL

Other Information Collected

diet

growth rates

radio tracking

residency

sonic tracking

Project Summary

Some Kemp’s ridleys set up home ranges in this area for as long as three years. Fewer loggerheads were present in the study area because they may prefer deeper waters. Green turtle numbers were also low, possibly due to sparse seagrass beds in the area. The total number of captures decreased in December through February. Recaptures were documented within and between sampling seasons, indicating foraging-site fidelity. A hawksbill/loggerhead hybrid was captured four times within one year. The study documented habitat-partitioning by different turtle species in Gullivan Bay. Kemp’s ridley turtles principally used areas of sand substrate with plumed worm tubes and live-bottom organisms; green turtles were found mainly in the seagrass beds in the northwestern portion of the study area.

Documents

No documents uploaded.

Literature/Reports Produced

Witzell, W.N., and J.R. Schmid. 2002. Investigation of immature sea turtles in the coastal waters of southwest Florida. In: Mosier, A., A. Foley, and B. Brost (comps.). Proc. 20th ISTS. NOAA Tech. Memo. NMFS-SEFSC-477, pp. 276-277.

Witzell, W.N., and J.R. Schmid. 2003. Multiple recaptures of a hybrid hawksbill-loggerhead turtle in the Ten Thousand Islands, southwest Florida. Herpetological Review 34:323-325.

Schmid, J.R. 2004. Determining essential habitat for the Kemp's ridley turtle in the Ten Thousand Islands, Florida. Final report submitted to Marine Turtle Grants Program. 16 pp.

Witzell, W.N., and J.R. Schmid. 2004. Immature sea turtles in Gullivan Bay, Ten Thousand Islands, southwest Florida. Gulf of Mexico Science 22:54-61.

Schmid, J.R. 2005. Essential habitat for Kemp's ridley turtles in the Ten Thousand Islands, Florida. Final report submitted to Florida Fish and Wildlife Conservation Commission, Marine Turtle Permit #147, 18 pp.

Witzell, W.N., and J.R. Schmid. 2005. Diet of immature Kemp's ridley sea turtles (Lepidochelys kempi) from Gullivan Bay, Ten Thousand Islands, southwest Florida. Bulletin of Marine Science 77:191-199.

Witzell, W.N., A.A. Geis, J.R. Schmid, and T. Wibbels. 2005. Sex ratio of immature Kemp's ridley turtles (Lepidochelys kempi) from Gullivan Bay, Ten Thousand Islands, south-west Florida. J. of the Marine Biological Association of the UK 85:205-208.

Schmid, J.R., W.N. Witzell, D.S. Addison, and D.W. Ceilley. 2005. Essential habitat for Kemp's ridley turtles in western Florida. Presentation at 25th ISTS, Savannah, GA, USA. 16-22 January 2005.