35599
Autonomous Passive Acoustic Monitoring in the Northwestern Gulf of Mexico
NW Gulf PAM
Data Set
Published / External
35600
Gulf of Mexico Autonomous Passive Acoustic Monitoring
Project
In Work
Bryde’s whales, Balaenoptera edeni, are the only year-round resident baleen whale in the Gulf of Mexico, have an estimated abundance of 33 individuals (CV 1.07) in the Gulf of Mexico population, and are found within a restricted range near the De Soto Canyon in the northeastern Gulf. Based on their localized distribution, low abundance, and recent evidence that this population represents a unique evolutionary lineage and exhibits very low levels of genetic diversity, the Natural Resources Defense Council (NRDC) has petitioned NMFS to list the Gulf of Mexico Bryde’s whale as an endangered species and define critical habitat to enhance their protection. The NRDC highlights the high levels of anthropogenic noise from shipping and seismic surveys in the Gulf of Mexico as a major stressor. Historical whaling records found balaenopterids, most likely Bryde’s whales, throughout a broader area than their currently known range, including the western and central portions of the northern Gulf of Mexico, though sightings are now rare in this region, despite substantial effort. Autonomous passive acoustic methods are the most successful tool for finding rare whale species in areas where they occur infrequently and areas where they were historically sighted by whalers. The objectives of this study are to collect passive acoustic data for use in investigations of 1) Bryde’s whale occurrence and distribution, and 2) ambient noise conditions in the western Gulf of Mexico. We deployed 5 calibrated autonomous acoustic instruments over a one year period from June 2016 – June 2017 along the 200 m isobaths throughout the western Gulf of Mexico predicted Bryde’s whale habitat. This will provide data to investigate whether, where, and when Bryde’s whales occupy this habitat and will be useful in designating critical habitat if this species is listed under the ESA. By using calibrated instruments, an additional goal will be to obtain data to characterize the ambient sound environment at these sites to determine whether acute or chronic anthropogenic noise sources pose a risk to this species.
The purpose of this study is to acoustically monitor an area of historical importance to a small population of resident baleen whales to 1) determine if they occur in waters beyond the northeastern Gulf of Mexico; 2) evaluate the seasonal occurrence and site fidelity at western Gulf sites; and 3) to characterize ambient noise conditions in this region of high shipping and seismic activity. We deployed 5 calibrated fixed passive acoustic recorders along the 200 m isobath in the region of predicted high densities on the northwestern Gulf of Mexico shelf to investigate whether Bryde’s whales can be found in this area and to characterize the ambient noise conditions. Given the small population size and unique genetic lineage of this stock of Bryde’s whales, it is imperative that we determine the extent of their range, seasonality of their distribution, and what noise conditions occur throughout their habitat in order to offer the best protection possible should this stock be listed under the Endangered Species Act.
Theme
Marine Mammal
Theme
Passive Acoustic Monitoring
Spatial
Gulf of Mexico
Southeast Fisheries Science Center
Miami
FL
USA
Data Set
Table (digital)
gov.noaa.nmfs.inport:35599
Lance Garrison
2016-11-10T09:18:09
SysAdmin InPortAdmin
2022-08-09T17:11:00
2021-04-29
Southeast Fisheries Science Center
SEFSC
75 Virginia Beach Drive
Miami
FL
33149
USA
(305)361-5761
www.sefsc.noaa.gov
8:00 a.m. - 4:30 p.m. EST
1001
Public
No
2021-04-29
1 Year
2022-04-29