This work builds upon and complements longer-term studies of movements and site fidelity of both Cuvier’s beaked whales (Ziphius cavirostris) and short-finned pilot whales (Globicephala macrorhynchus) off the North Carolina coast using photo-identification (photo-ID)

This work builds upon and complements longer-term studies of movements and site fidelity of both Cuvier’s beaked whales (Ziphius cavirostris) and short-finned pilot whales (Globicephala macrorhynchus) off the North Carolina coast using photo-identification (photo-ID)

This report forms part of a multi-institutional monitoring project intended to provide information on the species composition, population identity, density, and baseline behavior of marine mammals and sea turtles present in United States (U.S.) Navy range complexes along the U.S. Atlantic Coast.

This report forms part of a multi-institutional monitoring project intended to provide information on the species composition, population identity, density, and baseline behavior of marine mammals and sea turtles present in United States (U.S.) Navy range complexes along the U.S. Atlantic Coast.

Passive acoustic monitoring was conducted using High-frequency Acoustic Recording Packages (HARPs) deployed in waters offshore of Virginia, North Carolina, and Florida with support from the US Navy during 2016 - 2017. The HARPs recorded underwater sounds between 10 Hz and 100 kHz. Data analysis consisted of analyst scans of long-term spectral averages (LTSAs) and spectrograms, and automated computer algorithm detection when possible. Three frequency bands were analyzed for marine mammal vocalizations and anthropogenic sounds: (1) Lowfrequency, between 10-1000 Hz, (2) Mid-frequency, between 1,000-5,000 Hz, and (3) Highfrequency, between 1-100 kHz.

This report details part of a multi-institutional monitoring project intended to provide information 3 on the species composition, population identity, density, and baseline behavior of marine 4 mammals and sea turtles present in United States (U.S.) Navy range complexes along the U.S. 5 Atlantic Coast.

This report forms part of a multi-institutional monitoring project intended to provide information on the species composition, population identity, density, and baseline behavior of marine mammals and sea turtles present in United States (U.S.) Navy range complexes along the U.S. Atlantic Coast.

We have been conducting ongoing monthly aerial surveys off Cape Hatteras, NC, USA as part of the US Navy's marine species monitoring program in the Atlantic since 2011. We utilize line transect survey methods and extensively photograph all sightings to confirm species identification. Survey tracklines extend from shallow continental shelf waters, across the shelf break, to deep pelagic waters. From May 2011 through December 2014, 26,131km of trackline were flown, and 9,941 individual cetaceans were documented during 437 encounters. Nineteen species of cetaceans, including three mysticetes (Balaenoptera physalus, B. acutorostrata, Megaptera novaeangliae), five deep-divers (Physeter microcephalus, Kogia spp., Ziphius cavirostris, Mesoplodon europaeus, M. mirus), and eleven delphinids (Tursiops truncatus, Stenella frontalis, S. attenuate, S. coeruleoalba, S. clymene, S. longirostris, Steno bredanensis, Peponocephala electra, Lagenodelphis hosei, Grampus griseus and Globicephala macrorhynchus) were encountered. Similar surveys at the adjacent Onslow Bay, NC site yielded only 257 sightings (4,773 individuals representing nine species) despite nearly two times the survey effort flown (48,698km). At Cape Hatteras, minimum abundance estimates (i.e. uncorrected for availability or perception bias) were generated using spatio-temporal density surface modelling for species with sufficient detections. Predicted monthly abundance of T. truncatus varied between 170 (95% confidence interval; 0 - 17,100) and 3,450 (300 - 8,510). Monthly Stenella spp. abundance varied between 110 (0 - 360) and 1,720 (400 - 5,390). Monthly abundance of G. macrorhynchus varied between 10 (0 - 960) and 1,230 (220 - 4,300). These results demonstrate that the waters off Cape Hatteras support both higher diversity and density of cetaceans than adjacent waters along the US Atlantic coast. This site is included in the area of interest identified in six pending permits for large-scale, commercial seismic surveys. We suggest that the high density and diversity of cetaceans at this site warrants a special degree of concern by the US Bureau of Ocean Energy Management.

This is the fifth progress report of a monitoring program for protected marine species in waters offshore Cape Hatteras and Onslow Bay, North Carolina and Jacksonville, Florida. The results of aerial line transect surveys and vessel-based photo-ID surveys and passive acoustic monitoring are reported for the period from January 2012 through December 2012.

The results of this study provide valuable information on the performance of two whistle classifiers for delphinid species in the northwestern Atlantic Ocean. Although the manual classifier requires more time and effort for the detection and extraction of whistles, it proved to be more generalizable to novel datasets than the automated classifier and also allowed identification of acoustic encounters that did not have associated visual observations (i.e., non-sighted encounters).

Photo-Identification Analyses in the Cape Hatteras Study Area: 2022 Annual Progress Report