Abstract

The Duke Marine Geospatial Ecology Laboratory leads an ongoing collaboration of federal, state, academic, and independent research organizations who pool scientific data and expertise to develop marine mammal species density models spanning the U.S. east coast and southeast Canada. The models estimate absolute density, rendered as maps of the number of individual animals per 100 km², by statistically correlating sightings reported on shipboard and aerial surveys with oceanographic conditions. Since its initial publication in 2016, the project has expanded to utilize over 2.8 million linear kilometers of survey effort collected between 1992-2020, yielding density maps for over 30 species and multi-species guilds.

This page lists the latest available models and provides links to download their GIS files and documentation and explore them in an interactive online mapper. All of the models were most recently revised on 20 June 2022, as part of a comprehensive update developed for the U.S. Navy's Atlantic Fleet Training and Testing (AFTT) Phase IV Environmental Impact Statement. On 27 May 2023, we updated all models to include taxon-specific documentation and fixed some 5% / 95% confidence interval rasters (please see the model README.txt files for details). On 20 March 2024, we updated the North Atlantic right whale model's documentation again to reference the newly-released journal publication for that model. All density, CV, or standard error rasters for all taxa have remained unchanged since the initial 20 June 2022 release. If you performed an analysis on the 20 June 2022 release of those rasters, your analysis is still up to date.

This work was funded by the U.S. Navy to assist with complying with U.S. laws that require the Navy to assess the potential impacts to protected marine species resulting from military readiness activities. All marine mammals in the U.S. are protected under the Marine Mammal Protection Act (MMPA), and some marine species receive additional protection under the Endangered Species Act (ESA). As stipulated by the MMPA and ESA, information on the potential location and numbers of protected marine species is required in order to estimate how many animals might be affected by a specific activity. The Navy performs quantitative analyses to estimate the number of marine mammals and sea turtles that could be affected by at-sea training and testing activities. A key element of this quantitative impact analysis is knowledge of the abundance and concentration (density — the number of individual animals found per square kilometer of area) of the species in specific areas where those activities will occur.

Additional funding was provided by NOAA to further develop models of the North Atlantic right whale.

Citation

We are currently preparing a new peer-reviewed journal manuscript that will cover all of the 2022 models. In the meantime, when citing our methodology or results generally, please cite our 2016 journal publication and our 2023 report to the Navy. When citing the North Atlantic right whale model, please cite our 2024 journal publication about that model. When citing specific models for other taxa, please see the reference listed in its taxon-specific report or README.txt file.

Model resolution and units

All models have a spatial resolution of 5 km. Model outputs are given as GIS-compatible raster files in an Albers Equal Area projection with a cell size of 5000x5000 m. The unit of density is individuals / 100 km². To convert to individuals / 1 km², divide the raster values by 100. To convert to individuals per grid cell, i.e. individuals / 25 km², divide the raster values by 4.

Downloads

To download all models in a single zip file, click here (4.5 GB). All documentation is included in that zip, as well as the individual taxon zips below.

Retired Models

These models have been retired and replaced by more recent models listed above. They are retained here for reference purposes.

Acknowledgments

This project would not be possible without the contributions of many individuals and organizations. Above all, we acknowledge the work of those who collected, processed, and shared marine mammal and covariate data with us, and to those who funded the production of those data. In particular, we thank the observers, pilots, ship captains, and crew who collected the marine mammal observations that form the core of this analysis. The logos of these organizations appear at the top of this page and they named within our project report . Thank you all for the opportunity to analyze the data you produced; we hope you find this project a satisfactory outcome of your efforts.

Many thanks to colleagues who shared data, reviewed portions of our work, provided valuable advice, or answered technical questions, including: Susan Barco, Suzanne Bates, Elizabeth Becker, Olly Boisseau, Gary Buchanan, Steve Buckland, Sam Chavez-Rosales, Danielle Cholewiak, Tim Cole, Peter Corkeron, Mark Cotter, Erin Cummings, Genevieve Davis, Rob DiGiovanni, Megan Ferguson, Karin Forney, Lance Garrison, Caroline Good, Tim Gowan, Phil Hammond, Jolie Harrison, Katie Jackson, Beth Josephson, Bob Kenney, Christin Khan, Scott Kraus, Erin LaBrecque, Claire Lacey, Sophie Laran, Ben Laws, Patrick Lehodey, Gwen Lockhart, Kate Lomac-MacNair, Tiago Marques, Ryan McAlarney, Bill McLellan, David L. Miller, Keith Mullin, Doug Nowacek, Orla O'Brien, Ann Pabst, Richard Pace, Debi Palka, Eric Patterson, Ester Quintana-Rizzo, Jessica Redfern, Vincent Ridoux, Doug Sigourney, Len Thomas, Sofie Van Parijs, Melanie White, Amy Whitt, and Ann Zoidis.

We gratefully acknowledge Genevieve Davis and coauthors (Davis et al. 2017, 2020) for making passive acoustic monitoring data available for the purpose of evaluating baleen whale model predictions. These data appear in the accompanying taxon-specific reports for the baleen whales.

Funding for this project was provided by United States Fleet Forces Command and was managed on their behalf by Naval Facilities Engineering Systems Command Atlantic. Development of the model for North Atlantic right whale was co-funded by NOAA under a cooperative research agreement.

Certain data contributors requested that their programs or products be acknowledged in a specific way. We include these acknowledgements below.

Virginia Aquarium & Marine Science Center's Virginia CZM Wind Energy Area Surveys were funded by the Virginia Coastal Zone Management Program at the Department of Environmental Quality through Task 1 of Grant NA12NOS4190027 and Task 95.02 of Grant NA13NOS4190135 of the U.S. Department of Commerce, National Oceanic and Atmospheric Administration, under the Coastal Zone Management Act of 1972, as amended. The University of North Carolina Wilmington's Navy surveys were funded by U.S. Navy Fleet Forces Command with Joel Bell as the COTR. University of North Carolina Wilmington's right whale surveys were funded by NOAA. New England Aquarium's surveys of the Massachusetts and Rhode Island Wind Energy Areas, known in this report as the NLPSC and MMS-WEA programs, were funded by Massachusetts Clean Energy Center and the Bureau of Ocean Energy Management.

Funding for the development of HYCOM has been provided by the National Ocean Partnership Program and the Office of Naval Research. Data assimilative products using HYCOM are funded by the U.S. Navy. The 1/12 degree global HYCOM+NCODA Ocean Reanalysis was funded by the U.S. Navy and the Modeling and Simulation Coordination Office. Computer time was made available by the DoD High Performance Computing Modernization Program. The output is publicly available at https://hycom.org. The Ssalto/Duacs altimeter products were produced and distributed by the Copernicus Marine and Environment Monitoring Service (CMEMS) (https://marine.copernicus.eu). The altimetry and the Mesoscale Eddy Trajectory Atlas products were produced by Ssalto/Duacs and distributed by AVISO+ (https://www.aviso.altimetry.fr) with support from CNES, in collaboration with Oregon State University with support from NASA. CCMP vector wind analyses are produced by Remote Sensing Systems. Data are available at https://www.remss.com. This study has been conducted using E.U.Copernicus Marine Service Information, including SEAPODYM (doi: 10.48670/moi-00020) and Copernicus GlobColour (CMEMS product code OCEANCOLOUR_GLO_CHL_L4_REP_OBSERVATIONS_009_082).

Conflict of Interest Statement

As acknowledged in our 2016 publication, U.S. Navy Fleet Forces Command is one of the principal funders of this modeling project. For the 2016 publication, the Navy was given the opportunity to suggest spatial, temporal, and taxonomical resolutions and a geographic extent that would facilitate the Navy's use of the results in U.S. environmental regulatory processes. When the analysis was complete, the Navy was given opportunity to view preliminary results. Neither the Navy nor any other funder participated in the analysis of the data or the preparation of the manuscript. Since that publication, the Navy has continued to fund updates to the models under a similar arrangement.