Casey Key Loggerheads 2007
Mote Marine Laboratory

Dataset credit

Data provider
Mote Marine Laboratory
Originating data center
Satellite Tracking and Analysis Tool (STAT)
Project partner
Mote Marine Laboratory
University of South Florida - College of Marine Science

Project sponsor or sponsor description
Two projects, the Acoustic Environment of Loggerhead Sea Turtles and the Determination of Intra-season Clutch Frequency for Loggerhead Turtles, were funded by a grant awarded from the Sea Turtle Grants Program. The Sea Turtle Grants Program is funded from proceeds from the sale of the Florida Sea Turtle License Plate. Learn more at

Additional funding was provided by Longboat Key Turtle Watch and an anonymous donor, New Canaan Country School/Jeniam Foundation, Wooster School, Sarasota County Environmental Services, Virginia Miller, the Samek family on behalf of Kelly Samek, Curtis School, Comerica, Suntrust, and Community Foundation of Greater Lakeland.


Primary contact Tony Tucker Mote Marine Laboratory
Data entry Michael Coyne



Satellite tagging projects provide new data that address a variety of applied science contexts. This year's collaborative partners include Mote Marine Laboratory, University of South Florida, Univ. Georgia, Univ. Alabama-Birmingham, Duke Univ., West Connecticut State Univ., Florida A&M, Smithsonian, and National Geographic are all involved in various projects this nesting season.

A brief synopsis of the investigations includes:
Acoustic Study: The acoustic effects of undersea exploration and of vessel traffic are currently unknown for free-ranging sea turtles. The project will generate the first records of the acoustic environment of loggerhead sea turtles in inter-nesting habitats. Nesting females will be equipped with an acoustic bioprobe and a time-depth recorder before they swim away for an internesting interval. A recording tag will determine the acoustic environment experienced by turtles in the offshore environment. When a turtle returns to nest, the acoustic datalogger will be removed. The data gleaned and refinement of methodology developed from a nearshore study is a prerequisite before any studies are attempted on acoustic environments experienced by turtles in offshore realms. The project is a developmental step toward a more complete understanding of threats faced by sea turtles from boat traffic and opening Florida’s nearshore and offshore shelf to natural resource exploration.

Clutch frequency study: In deriving population density and abundance estimates for a species, adequate sampling regimes are needed to obtain non-biased population parameters. The sampling of sea turtle populations generally occurs at rookeries for that proportion of reproductive females nesting in a given year. Acknowledged problems inherent to adequately sampling these populations include tag loss, incomplete capture-recapture records, variation in remigration schedules, variable female reproductive output, and unrecorded nesting events occurring outside the sampling area. A serious consequence of estimating female fecundity is to overestimate populations, which would be detrimental to the aims of the U. S. Loggerhead Recovery Team.
To derive a more rigorous determination of clutch frequency, it is now possible to use satellite tags to evaluate how many nests a female may deposit within a season. The methods require that females be instrumented early in the nesting season and followed through the reminder of all internesting intervals until a final nest and then a post-reproductive migration. Although this is not the first time that loggerheads have been tagged in Florida nor in the Gulf of Mexico, all previous studies have generally tagged toward the end of the nesting season (July-August) and therefore would provide underestimates of annual fecundity.

This study proposes to determine clutch frequency of loggerheads at a primary nesting beach for loggerheads in the Gulf of Mexico. Satellite tags as well as standard Inconel flipper tags and PIT tags will be attached to nesting female loggerheads at either Casey Key or Manasota Key during May. Females will be tracked through the remainder of the nesting season to determine clutch frequency and site fidelity. Other valuable research byproducts related to conservation will be the determination of internesting movement, exposures levels to red tide, and other risks faced during the internesting and post-nesting movements. Pilot studies in 2005 and 2006 have previously determined the feasibility and logistics of such a study but were geared to tagging later in the season. By deploying tags early in May, a more accurate determination of clutch frequency will be obtained. These results would be comparable for other beaches in Florida, but are ideally suited to beaches that also conduct simultaneous night time tag patrols, such as on Manasota and Casey.



Supplemental information

Visit STAT's project page for additional information.




Attributes described below represent those in the original dataset provided by the provider.
Only minimum required attributes are visible and downlodable online. Other attributes may be obtained upon provider's permission unless otherwise noted below.

This section explains attributes included in the original dataset. OBIS-SEAMAP restricts the attributes available to the public to date/time, lat/lon and species names/counts only. Should you need other attributes described here, you are encouraged to contact the data provider.

Attributes in dataset provided

Attribute (table column)Description
Marine mammals0
Sea turtles4,659
Rays and sharks0
Other species0
Non spatial0
Non species0
Date, Begin2007-05-14
Date, End2008-05-30
Temporal prec.111111
Latitude19.14 - 28.26
Longitude-91.73 - -76.44
Coord. prec.3 decimal digits
Data typeTelemetry location
TracklinesYES (ID: 391)
Contr. throughSatellite Tracking and Analysis Tool
Sharing policy Permission required
Also availalbe from None
See metadata in static HTML
See metadata in FGDC XML
See download history / statistics