Index Nesting Beach Survey Totals (1989-2009)
This article provides annual data from the Florida Index Nesting Beach Survey Program administered by FWRI.
For the past 21 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 beaches and between years. The INBS program is suited to these trend assessments because of its detailed and constant effort by location and date, and its specialized annual training of beach surveyors.
Approximately 30 percent of Florida's SNBS beach length is surveyed under INBS criteria. INBS nest counts represent approximately69 percent of known loggerhead nesting in Florida, 74 percent of known green turtle nesting, and 34 percent 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 (or nearly 200 miles) have been divided into zones, known as core index zones, averaging 0.8 km (half-mile) in length. Annually, between 1989 and 2009, these core index zones were monitored daily during the 109-day sea turtle index-nesting season (May 15 to August 31). On all index beaches, researchers recorded nests and nesting attempts by species, nest location, and date.
Loggerhead Nests
This graph shows annual loggerhead nests counted at core index nesting beaches in Florida during the period 1989 through 2009. 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. These core INBS nest-count data do not include an additional set of beach lengths in the Florida Panhandle added to the INBS program in 1997. Florida's loggerhead nest counts on Index beaches have declined significanly over the period and have the steepest decline following 1998.
This graph shows annual loggerhead nests counted at Index beaches in the Florida Panhandle, 1997 through 2009.
Because of a concern over declines in annual loggerhead nest counts, a detailed analysis was conducted to describe loggerhead nesting trends (1989-2007). The following article describes this analysis.
Green Turtle Nests
This graph of annual green turtle nesting at core index nesting beaches in Florida shows a mostly two-year periodicity in nest numbers. Between 1989 and 2009, the annual number of green turtle nests at core index beaches ranged from 267 to 9091. The green turtle nesting trend is dramatically different from the loggerhead nesting trend, with green turtle nests increasing by a factor of ten over the 21-year period.
View Graph of Core Florida Index Nests for Green Turtles
Leatherback Nests
This graph illustrates annual leatherback nesting at core index beaches. The annual number of leatherback nests at the core set of index beaches ranged from 27 to 615 between 1989 and 2009. Florida received a record number of leatherback nests on Index beaches in 2009. Like the trend for green turtles, leatherback nest counts have been increasing exponentially.
View Graph of Core Florida Index Nests for Leatherbacks
