Megan C. Ferguson

4. Biologically Important Areas for Selected Cetaceans Within U.S. Waters – West Coast Region

In this review, we combine existing published and unpublished information along with expert judgment to identify and support the delineation of 28 Biologically Important Areas (BIAs) in U.S. waters along the West Coast for blue whales, gray whales, humpback whales, and harbor porpoises. BIAs for blue whales and humpback whales are based on high concentration areas of feeding animals observed from small boat surveys, ship surveys, and opportunistic sources. These BIAs compare favorably to broader habitat-based density models. BIAs for gray whales are based on their migratory corridor as they transit between primary feeding areas located in northern latitudes and breeding areas off Mexico. Additional gray whale BIAs are defined for the primary feeding areas of a smaller resident population. Two small and resident population BIAs defined for harbor porpoises located off California encompass the populations’ primary areas of use. The size of the individual BIAs ranged from approximately 171 to 138,000 km. The BIAs for feeding blue, gray, and humpback whales represent relatively small portions of the overall West Coast area (< 5%) but encompass a large majority (77 to 89%) of the thousands of sightings documented and evaluated for each species. We also evaluate and discuss potential feeding BIAs for fin whales, but none are delineated due to limited or conflicting information. The intent of identifying BIAs is to synthesize existing biological information in a transparent format that is easily accessible to scientists, managers, policymakers, and the public for use during the planning and design phase of anthropogenic activities for which U.S. statutes require the characterization and minimization of impacts on marine mammals. To maintain their utility, West Coast region BIAs should be re-evaluated and revised, if necessary, as new information becomes available.

Alaska marine mammal stock assessments, 2015

NOTE – NMFS is in the process of reviewing humpback whale stock structure under the Marine Mammal Protection Act (MMPA) in light of the 14 Distinct Population Segments established under the Endangered Species Act (ESA) (81 FR 62259, 8 September 2016). A complete revision of the humpback whale stock assessments will be postponed until this review is complete. In the interim, new information on humpback whale mortality and serious injury is provided within this report.

1. Biologically Important Areas for Cetaceans Within U.S. Waters - Overview and Rationale

We outline the rationale and process used by the Cetacean Density and Distribution Mapping (CetMap) Working Group to identify Biologically Important Areas (BIAs) for 24 cetacean species, stocks, or populations in seven regions within U.S. waters. BIAs are reproductive areas, feeding areas, migratory corridors, and areas in which small and resident populations are concentrated. BIAs are region-, species-, and time-specific. Information provided for each BIA includes the following: (1) a written narrative describing the information, assumptions, and logic used to delineate the BIA; (2) a map of the BIA; (3) a list of references used in the assessment; and (4) a metadata table that concisely details the type and quantity of information used to define a BIA, providing transparency in how BIAs were designated in a quick reference table format. BIAs were identified through an expert elicitation process. The delineation of BIAs does not have direct or immediate regulatory consequences. Rather, the BIA assessment is intended to provide the best available science to help inform regulatory and management decisions under existing authorities about some, though not all, important cetacean areas in order to minimize the impacts of anthropogenic activities on cetaceans and to achieve conservation and protection goals. In addition, the BIAs and associated information may be used to identify information gaps and prioritize future research and modeling efforts to better understand cetaceans, their habitat, and ecosystems.

Increased sightings of subArctic cetaceans in the eastern Chukchi Sea, 2008–2016: population recovery, response to climate change, or increased survey effort?

AbstractCetacean occurrence in the Chukchi Sea is seasonal and primarily driven by annual sea ice retreat and prey occurrence in spring through fall. Humpback whales (Megaptera novaeangliae), fin whales (Balaenoptera physalus), and minke whales (Balaenoptera acutorostrata), although often found in polar waters elsewhere, are not common in the eastern Chukchi Sea, and here are referred to as “subArctic” species. Increasing numbers of these subArctic cetacean species were documented during aerial surveys in the eastern Chukchi Sea (67°–72°N, 157°–169°W) in July–October 2008–2016. The majority (78%) of these sightings occurred on the continental shelf in the south-central Chukchi Sea (67°–69°N, 166°–169°W) in August and September. During similar aerial surveys in 1982–1991, there was a complete lack of sightings of subArctic species. The disparity in sightings between the two time periods could be due to increased marine mammal survey effort in recent years during the months when subArctic cetacean species would be expected to occur, population recoveries from commercial whaling, climate change, or, most likely, a combination of all three.

6. Biologically Important Areas for Cetaceans Within U.S. Waters – Gulf of Alaska Region

We integrated existing published and unpublished information to delineate Biologically Important Areas (BIAs) for fin, gray, North Pacific right, and humpback whales, and belugas in U.S. waters of the Gulf of Alaska. BIAs are delineated for feeding, migratory corridors, and small and resident populations. Supporting evidence for these BIAs came from aerial-, land-, and vessel-based surveys; satellitetagging data; passive acoustic monitoring; traditional ecological knowledge; photoand genetic-identification data; whaling data, including catch and sighting locations and stomach contents; prey studies; and anecdotal information from fishermen. The geographic extent of the BIAs in this region ranged from approximately 900 to 177,000 km. Information gaps identified during this assessment include (1) reproductive areas for fin, gray, and North Pacific right whales; (2) detailed information on the migration routes of all species; (3) detailed information on the migratory timing of all species except humpback whales; and (4) cetacean distribution, density, and behavior in U.S. Gulf of Alaska waters off the continental shelf. To maintain their utility, these BIAs should be re-evaluated and revised, if necessary, as new information becomes available.

National Oceanic and Atmospheric Administration’s Cetacean and Sound Mapping Effort: Continuing Forward with an Integrated Ocean Noise Strategy

To help manage chronic and cumulative impacts of human activities on marine mammals, the National Oceanic and Atmospheric Administration (NOAA) convened two working groups, the Underwater Sound Field Mapping Working Group (SoundMap) and the Cetacean Density and Distribution Mapping Working Group (CetMap), with overarching effort of both groups referred to as CetSound, which (1) mapped the predicted contribution of human sound sources to ocean noise and (2) provided region/time/species-specific cetacean density and distribution maps. Mapping products were presented at a symposium where future priorities were identified, including institutionalization/integration of the CetSound effort within NOAA-wide goals and programs, creation of forums and mechanisms for external input and funding, and expanded outreach/education. NOAA is subsequently developing an ocean noise strategy to articulate noise conservation goals and further identify science and management actions needed to support them.