Loggerhead Sea Turtle (Caretta caretta) Occurrence Records in the Mediterranean Sea

This dataset contains georeferenced occurrence records of the Loggerhead Sea Turtle (Caretta caretta) within the Mediterranean Sea from 1962 to 2025. The data were obtained from the Global Biodiversity Information Facility (GBIF) and filtered to include only marine points falling within a defined Mediterranean polygon. Duplicated coordinates were removed.

Usage

data("caretta")

Format

A data frame with 8340 rows and 5 variables:

decimalLongitude

Numeric. Longitude coordinates (WGS84).

decimalLatitude

Numeric. Latitude coordinates (WGS84).

year

Integer. Year in which the observation was recorded.

species

Character. The species name (Caretta caretta).

coordinateUncertaintyInMeters

Numeric. Positional uncertainty of the coordinates, in meters.

Source

Global Biodiversity Information Facility (GBIF)
GBIF Occurrence Download https://doi.org/10.15468/dl.9jcjrm
Accessed from R via rgbif (https://github.com/ropensci/rgbif) on 2025-02-07

Details

The data were accessed through the GBIF API and clipped spatially using a Mediterranean Sea polygon (https://www.marineregions.org/gazetteer.php?p=details&id=1905). All records were filtered to ensure presence-only data with valid geographic coordinates. Duplicate coordinate pairs were removed to reduce redundancy.

This dataset is used as a real-world example throughout the GeoThinneR package and the accompanying article.

For reproducibility, the GBIF download script is included in data-raw/caretta_download.R.

The Mediterranean Sea polygon used to spatially filter the records was download from Marineregions.org: https://www.marineregions.org/gazetteer.php?p=details&id=1905. It is distributed with the package as inst/extdata/mediterranean_sea.gpkg and used in the data-raw/caretta_download.R script.