Cetaceans are protected worldwide but vulnerable to incidental harm from an expanding array of human activities at sea. Managing potential hazards to these highly-mobile populations increasingly requires a detailed understanding of their seasonal distributions and habitats. Using distance sampling methodology, we built statistical models of cetacean density—the number of individual animals found per square kilometer and produced maps showing average density across the modeled region.
Cetaceans are protected worldwide but vulnerable to incidental harm from an expanding array of human activities at sea. Managing potential hazards to these highly-mobile populations increasingly requires a detailed understanding of their seasonal distributions and habitats. Using distance sampling methodology, we built statistical models of cetacean density—the number of individual animals found per square kilometer and produced maps showing average density across the modeled region.
Marine mammals are protected worldwide but vulnerable to incidental harm from an expanding array of human activities at sea. The U.S. Navy takes responsibility for reviewing and evaluating the potential environmental impacts of conducting at-sea training and testing operations, and performs quantitative analyses that require estimates of species density — the number of individual animals found per square kilometer of area. For each marine mammal and sea turtle species present in their study areas throughout the Pacific Ocean and Gulf of Alaska, the Navy uses the best available region- and species-specific density data to support their quantitative impact analyses, and produces maps that show average density across these regions.
The Marine-life Data and Analysis Team (MDAT) is comprised of the Marine Geospatial Ecology Lab (MGEL) of Duke University, the NOAA National Centers for Coastal Ocean Science (NCCOS), the NOAA Northeast Fisheries Science Center (NEFSC), The Nature Conservancy (TNC) and Loyola University Chicago. MDAT works with regional ocean data portals, councils, and stakeholders to characterize and map marine life along the US Atlantic Coast. MDAT collaborations have produced individual species or species guild products for over a hundred species across three taxa: marine mammals, avian species, and fish species. MDAT also provides summary products that are built upon the individual species data layers to allow quick access to map summaries about potential biological, management, or sensitivity groups of interest. Types of summary products include total abundance or biomass, species richness, and species diversity indices that can aid the user in seeing broad patterns in the underlying data or model results.
Cetaceans are protected worldwide but vulnerable to incidental harm from an expanding array of human activities at sea. Managing potential hazards to these highly-mobile populations increasingly requires a detailed understanding of their seasonal distributions and habitats. Using distance sampling methodology, we built statistical models of cetacean density—the number of individual animals found per 25 square kilometer and produced maps showing average density across the modeled region.
Loggerhead turtles (Caretta caretta) are a globally vulnerable species of marine turtle. The Mediterranean Sea subpopulation, which ranges throughout the entire Mediterranean basin, is listed as least concern by the International Union for the Conservation of Nature (IUCN), but experiences significant threats in the region including bycatch in fisheries, climate change, coastal development, and marine pollution. Broad-scale patterns of distribution and abundance can provide regional managers a tool to effectively conserve and manage this species at basin and sub-basin scales.
As human activities expand beyond national jurisdictions to the high seas, there is increasing need to consider anthropogenic impacts to species that inhabit these waters. The current scarcity of scientific observations of cetaceans in the high seas impedes the assessment of population-level impacts of these activities. The U.S. Navy Atlantic Fleet Training and Testing Area extends from a well-surveyed region within the U.S. Exclusive Economic Zone into a large region of the western North Atlantic sparsely surveyed for cetaceans. We modeled densities of 15 cetacean taxa using available line transect survey data and habitat covariates and extrapolated predictions to sparsely surveyed regions.