The Northeast Regional Ocean Council and the Mid-Atlantic Regional Council on the Ocean (MARCO) collaborated to fund the development of maps of marine life to support ocean planning and management. Researchers at several institutions who work collaboratively as the Marine-life Data and Analysis Team (MDAT) assembled a collection of new maps that represents one of the largest known efforts globally to assemble and disseminate spatial data for multiple species and taxa of marine life. The Marine Geospatial Ecology Lab at Duke University led the overall MDAT effort and developed cetacean maps for the entire Atlantic coast. The methods used to develop the cetacean maps were published in the journal Nature Scientific Reports.

Cetacean individual species products

Cetacean density model results are the predicted number of animals per 100 square kilometers for a specific temporal period. Source data used to create the models are from 1992 through 2019. Model resolution is 10km x 10km (except for NARW products which are at 5km X 5km) and models were generated with an original extent of approximately the entire US east coast EEZ plus a portion of southeast Canada. Species-specific seasons are based on patterns in the sightings and reports in the literature. Full documentation for every individual model can be accessed online.

Characterizations of model uncertainty

Several measures of model uncertainty are provided with each habitat-based density model. The percentile maps reflect the statistical uncertainty of the Generalized Additive Models that are predicting density from environmental predictors. The uncertainty at a given location relates mainly to how well the environmental conditions that occurred there were surveyed (via remote sensing), and how variable conditions are throughout the year.

5% Confidence Interval - This measure indicates that the density of animals predicted by the model exceeds what is shown on the map 95% of the time.

95% Confidence Interval - On the 95th percentile map, the density of animals predicted by the model exceeds what is shown on the map only 5% of the time.

Standard Error - Standard error estimates how close the estimated density is likely to be to the actual density, accounting for the number of sightings that were made, the modeled taxon, and how effectively density was modeled statistically from the environmental variables. The units of standard error are the same as density. The standard error estimate does not account for the uncertainty in either the detection functions (which model the probability of detecting the taxon given its distance from the survey trackline) or the estimates of availability or perception bias (the tendencies to fail to detect the animal because it is submerged and unavailable for observation, or because it displays cryptic behaviors, is small and hard to see, etc.)

Coefficient of variation - The CV is the ratio of the standard error to the estimated density, and helps inform users about the magnitude of variation in model predictions from one place to another. Values greater than 1, i.e. where the standard error is greater than the density estimate, indicate substantial uncertainty. When high CVs occur where the density estimate is very low, as is often the case, there is little cause for concern. But when high CVs occur where the density estimate is high, it suggests the model cannot predict density well there.

More information


Any use of the data should be accompanied by the following citations:

Roberts J.J., Best B.D., Mannocci L., Fujioka E., Halpin P.N., Palka D.L., Garrison L.P., Mullin K,D., Cole T.V.N., Khan C.B., McLellan W.M., Pabst D.A., Lockhart G.G. (2016) Habitat-based cetacean density models for the U.S. Atlantic and Gulf of Mexico. Scientific Reports 6: 22615. doi: 10.1038/srep22615.

Roberts J.J., Mannocci L., Halpin P.N. 2017. Final Project Report: Marine Species Density Data Gap Assessments and Update for the AFTT Study Area, 2016-2017 (Opt. Year 1). Document version 1.4. Report prepared for Naval Facilities Engineering Command, Atlantic by the Duke University Marine Geospatial Ecology Lab, Durham, NC.

Roberts J.J., Mannocci L., Schick R.S., Halpin P.N. 2018. Final Project Report: Marine Species Density Data Gap Assessments and Update for the AFTT Study Area, 2017-2018 (Opt. Year 2). Document version 1.2 - 2018-09-21. Report prepared for Naval Facilities Engineering Command, Atlantic by the Duke University Marine Geospatial Ecology Lab, Durham, NC.

Curtice C., Cleary J., Shumchenia E., Halpin P.N. 2019. Marine-life Data and Analysis Team (MDAT) technical report on the methods and development of marine-life data to support regional ocean planning and management. Prepared on behalf of the Marine-life Data and Analysis Team (MDAT). Accessed at: http://seamap.env.duke.edu/models/MDAT/MDAT-Technical-Report.pdf


Marine Geospatial Ecology Lab (MGEL) at Duke University. This product was developed by MGEL in collaboration with colleagues at the National Oceanic and Atmospheric Administration (NOAA) National Marine Fisheries Service (NMFS), the University of North Carolina, Wilmington (UNCW), the Virginia Aquarium & Marine Science Center (VAMSC), the Fish and Wildlife Research Institute (FWRI) of the Florida Fish and Wildlife Conservation Commission, the Atlantic Marine Conservation Society, the Clearwater Marine Aquarium Research Institute, the Woods Hole Oceanographic Institute, the Massachusetts Clean Energy Center, the Bureau of Ocean Energy Management, the Maryland Dept. of Natural Resources, Tetra Tech and HDR. It was derived from habitat-based density models for cetaceans built from shipboard and aerial line transect surveys conducted at sea between 1992 and 2019 by the NMFS Northeast and Southeast Fisheries Science Centers, UNCW, VAMSC, the New Jersey Department of Environmental Protection, the Riverhead Foundation for Marine Research & Preservation, the New York Dept. of Environmental Conservation, the Center for Coastal Studies, and multiple teams surveying for North Atlantic right whales in the southeast U.S., including those led by FWRI, New England Aquarium, Georgia Dept. of Natural Resources, and Wildlife Trust / EcoHealth Alliance / Sea to Shore Alliance. The UNCW surveys were funded by U.S. Navy Fleet Forces Command and NOAA. VAMSC surveys in Virginia 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 from NOAA, under the Coastal Zone Management Act of 1972, as amended. The southeast U.S. right whale surveys were funded by NOAA, the U.S. Army Corps of Engineers, the U.S. Coast Guard, the U.S. Navy, the Georgia Department of Natural Resources, the South Carolina State Port Authority, and the National Fish and Wildlife Foundation. The density models were initially developed with funding from the National Aeronautics and Space Administration and U.S. Navy Fleet Forces Command, and further elaborated with funding from the Northeast Regional Ocean Council. For more information, please contact Jason Roberts (jason.roberts@duke.edu).

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