PROJECTS

Cetacean and Seabird Data During the Mariana Archipelago Cetacean Survey

The Pacific Marine Assessment Program for Protected Species (PacMAPPS) survey occurred from 1 August to 26 August 2021, beginning and ending in Kodiak, AK. Over the course of the survey, a total of 2,330 km of on-effort tracklines were surveyed in suitable weather conditions, and a total of 687 sightings of marine mammals were documented (including duplicates and resights).

The overall goal of this study was to include the 2018 survey data in the previous 1991–2014 modeling dataset in order to improve SMDs for the CCE study area. Specific objectives included: Generating multi-year average density surfaces for the Navy and others to use in their long-term (2–7 year) environmental planning efforts; and Providing updated abundance and “minimum population size (Nmin)” estimates as defined in the Guidelines for Assessing Marine Mammal Stocks (National Oceanic and Atmospheric Administration 2016).

The 2018 California Current Ecosystem Survey (CCES) was a joint project of the Marine Mammal and Turtle Division (MMTD) and the Fisheries Resources Division (FRD) of National Oceanographic and Atmospheric Administration’s (NOAA) Southwest Fisheries Science Center (SWFSC). The survey was conducted over the course of 7 legs aboard the NOAA ship Reuben Lasker between 26 June and 4 December 2018 (Table 1). CCES was an assessment survey for coastal pelagic fish stocks, marine mammals, seabirds, and oceanography along the west coasts of southern Canada (Vancouver Island), US, and northern Mexico (Baja California), out to a distance of approximately 200 nautical miles offshore (Fig. 1). MMTD and FRD worked jointly aboard the vessel during Legs 1 through 4 (OMAO Project No. RL-18-03) (Tables 1, 2a, and 2b), during which the vessel surveyed off the coasts of Vancouver Island and the US West Coast. Only MMTD operations were conducted during Legs 5 through 7 (OMAO Project No. RL-19- 01), during which the vessel surveyed off the US West Coast and Mexico. This document covers the work conducted by MMTD (MMTD Survey No. 1651). Work conducted by FRD is presented separately (Stierhoff et al. 2019).

Here we present analyses of the DASBR deployments from the CCES 2018 project. We provide information on the times and locations of drift deployments and retrievals. Each drift is also illustrated on maps of the study area. We present analyses of cetacean echolocation detections 2 from DASBR recordings including those from beaked whales, sperm whales, and NBHF species. As in the previous 2016 study, beaked whale detections were dominated by Cuvier’s beaked whale. All the beaked whale species detected in 2016 were also detected in this 2018 study, plus the addition of a signal, designated BWC that had been previously detected in the central and western Pacific, but not previously in the eastern Pacific. Sperm whales and NBHF species were detected throughout the study area.

The primary goals of Winter HICEAS 2020 were to collect data required to estimate the abundance and distribution, examine the population structure, and understand the habitat of cetaceans around the main Hawaiian Islands during the winter months (January–March). There were 5 major research components to the project: visual observations for cetaceans following a line-transect survey design; passive acoustic monitoring for cetaceans using towed hydrophone arrays, sonobuoys, and autonomous drifting acoustic recorders; collection of photographs and tissue samples and deployment of satellite tags for select cetacean groups; visual observations for seabirds following a strip-transect survey design; and ecosystem measurements for assessment of cetacean and seabird habitat.

The primary goals of HICEAS 2017 were to collect data required to estimate the abundance and distribution, examine the population structure, and understand the habitat of cetaceans within U.S. waters around the Hawaiian Islands. There were 5 major research components to HICEAS 2017: visual observations for cetaceans following a line-transect survey design; passive acoustic monitoring for cetaceans using towed hydrophone arrays, sonobuoys, and autonomous drifting acoustic recorders; collection of photographs and tissue samples and deployment of satellite tags for select cetacean groups; visual observations for seabirds following a strip-transect survey design; and ecosystem measurements for assessment of cetacean and seabird habitat.

To effectively protect and manage marine mammals, contemporary information on their abundance and distribution is essential. Several factors influence presentday insight including the accessibility of the study area and the degree of difficulty in locating and studying target species.

During this survey, the visual team surveyed 4,504 kilometers (km) of ‘full-effort,’ which included 349 km of ‘transit-effort.’ There was an additional 375 km of ‘fog-effort’ (transect and transit). Based on total effort, there were 802 sightings (1,998 individuals) of 13 confirmed marine mammal species, with an additional 162 sightings (228 individuals) of unidentified cetaceans and pinnipeds (including those recorded on transit and during off-effort mode).

During this project, the visual survey covered a total of 760 kilometers (410 nautical miles) on-effort while transit and fog effort legs accounted for 553 km (298 nm). There were a total of 96 sightings (453 individuals) of 11 confirmed marine mammal species; these included fin, humpback, gray, and minke whales as well as killer whales, Dall’s and harbor porpoise, Pacific white-sided dolphins and Steller sea lions, harbor seals and sea otters. Additionally, there were 36 sightings (46 individuals) of unidentified large whales, dolphins and pinnipeds. Acoustically, operations were conducted 24-hours/day surveying a total of 3,519 km (1,900 nm) and recording 49 acoustic detections of sperm whales and killer whales. Photographs of nineteen individual killer whales and four fin whales were obtained on this cruise and compared to existing catalogs.