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Index Nesting Beach Survey Totals (1989-2007)

Follow this link to the results of a recent analysis of trends in nesting by loggerhead turtles (1989-2007).

For the past 19 years, the Index Nesting Beach Survey (INBS) has coordinated a detailed sea turtle nesting-trend monitoring program in conjunction with the Statewide Nesting Beach Survey (SNBS) program. The INBS program was established with a set of standardized data-collection criteria to measure seasonal nesting, and to allow accurate comparisons between both beaches and years.  The reliability of these comparisons results from the uniformity of beach-survey effort in space and time, from the spatial and temporal detail of surveys (or, the space and time of the surveys), and from the specialized annual training of beach surveyors.

Approximately 30% of Florida’s SNBS beach length is surveyed under INBS criteria.  INBS nest counts represent approximately 69% of known loggerhead nesting in Florida, 74% of known green turtle nesting, and 34% of known leatherback nesting.  The Florida Fish and Wildlife Conservation Commission (FWC) coordinates INBS data collection through a network of permit holders consisting of federal, state, and local park personnel, other government agency personnel, members of conservation organizations, university researchers, and private citizens. Fish and Wildlife Research Institute (FWRI) staff members coordinate data collection, provide training, and compile annual survey data for publication and dissemination.

Under the core INBS program, 320 kilometers (km) of nesting beach has been divided into zones, known as core index zones, averaging 0.8 km in length. Each year, from 1989 to 2007, these core index zones were monitored daily during the 109-day sea turtle index nesting season beginning May 15 and ending August 31. On all index beaches, researchers record nests and nesting attempts by species, the location of the nest, and date.

The core INBS sea turtle nest-count data below do not include an additional set of beach lengths added to the INBS program since 1997.  These beach lengths were added to extend geographic coverage of the INBS program.  Excluding these INBS additions allows a uniform comparison for the period of 1989 through 2007.  In 2006, these INBS additions made up only 0.7% of loggerhead nests, 0.2% of green turtle nests, and 0.0% of leatherback nests in the total Florida INBS nest count.

Loggerhead Nests

This graph shows annual loggerhead nests counted at core index nesting beaches in Florida during the period 1989 - 2007. The survey effort at core beaches did not vary among years.  The annual number of loggerhead nests at the core set of index beaches ranged from 28,074 to 59,918 nests.

View Graph of Core Florida Index Nests for Loggerheads