This map shows leatherback and loggerhead sea turtle sightings per unit effort for the spring and summer seasons in the northwest Atlantic.
This map displays data from The Nature Conservancy’s Northwest Atlantic Marine Ecoregional Assessment (NAMERA), which utilizes effort-corrected sightings data from NMFS-NEFSC Aerial Surveys, NMFS-NEFSC Shipboard Surveys, and the North Atlantic Right Whale Consortium Database. The validity of sightings was carefully screened and verified by United States Navy contractors before inclusion in the model. Sightings for each ten-minute square were divided by the survey effort for each ten-minute square to calculate Sightings per Unit Effort (SPUE). SPUE is an analysis technique designed to correct for survey effort and show the relative abundance of species in areas that are surveyed. While this map attempts to correct for survey effort, some areas were surveyed significantly less than others and therefore certainty in those areas is relatively limited. This dataset may not capture the full extent of sea turtle sightings due to the difficulty of spotting and identifying species. Ten-minute squares where survey effort equaled zero were excluded from the dataset. Please see metadata for more information on these datasets.
We are working to develop new maps that incorporate data from recent offshore surveys and other sources.
Support for Regional Ocean Planning
For information about how these data and maps are being developed with stakeholder input and used to support regional ocean planning, please visit the marine life page on the Northeast Regional Planning Body’s website.