Pacific Technical Reports

Behavior and Distribution Bull Trout off Washington

For the period of funding, Dr. Will Gough has been working at the Marine Mammal Research Program (MMRP) on a number of goals that will build capacity within Hawaii and advance the Navy’s goals related to the long-term health of protected marine mammal species. These goals relate to Dr. Gough’s expertise working with accelerometry-based biologging tags and include: setting up infrastructure at the MMRP to maintain large quantities of tag data, collecting novel data and expanding existing datasets through field efforts, training members of the Navy and MMRP to work effectively with accelerometry data and biologging devices, develop training materials and short-form workshops to disseminate knowledge of accelerometry data processing and analysis more broadly within the Hawaiian community, and use new and existing datasets to answer questions of relevance to the Navy and other organizations tasked with monitoring and management of protected species.

The National Oceanic and Atmospheric Administration (NOAA) Alaska Fisheries Science Center has maintained passive acoustic recorder moorings in areas of interest to the US Navy in the Gulf of Alaska (GOA). Archival data from three of these sites were analyzed for the timing and occurrence of key cetacean species. In addition, three subsurface passive acoustic moorings were deployed for a year (fall 2023 to fall 2024) in areas of mutual interest to NOAA and the Navy. Two of these new moorings, located along the western GOA slope, were redeployed in 2024.

In the Pacific, the Marine Mammal Monitoring on Navy Ranges (M3R) program maintains systems that continuously run algorithms to detect, classify and localize marine mammals year-round on the U.S. Navy’s deep-water Southern California Antisubmarine Warfare Range (SOAR) in Southern California and the Pacific Missile Range Facility (PMRF) off Kaua‘i, Hawai‘i. Long-term archive data collected on these ranges allow for numerous types of studies on species inhabiting the ranges, including the monitoring of abundance, behavioral responses to naval activities, and habitat usage. They also provide the opportunity to study ambient sound levels and soundscapes. In FY24 the M3R program had five goals for SOAR and PMRF: Support real-time monitoring of on-water tagging operations Collection and postprocessing of M3R binary archives and periodic broadband recordings Data preservation: conversion of Alesis recordings to M3R packet recorder format SOAR Continuous Active Sonar Behavioral Response Study (CAS BRS) DICASS sonobuoy receiver adaption in preparation for deployment at SOAR.

Beaked whales (Family Ziphiidae; Order Cetacea) are the least well-described group of marine mammals because they conduct very long deep dives, spend little time on the surface where they display cryptic behavior, and are difficult to identify due to the similarity between species. Beaked whales are also known to be susceptible to high-energy sound sources in the ocean (e.g. seismic research, sonars used by military activities).

In August 2023 and February 2024, Cascadia Research Collective (CRC) conducted small boat-based satellite tagging of odontocetes at the Pacific Missile Range Facility (PMRF), with acoustic support from Naval Information Warfare Center (NIWC) Pacific and Naval Undersea Warfare Center (NUWC) Newport, directing the tagging boat towards locations of acoustic detections on the range. Seventeen days of tagging effort were conducted over the two years during the biannual Submarine Command Course (SCC) training events. In total 19 odontocetes were tagged: 14 short-finned pilot whales (Globicephala macrorhynchus), 3 common bottlenose dolphins (Tursiops truncatus), 1 pantropical spotted dolphin (Stenella attenuata), and 1 melon-headed whale (Peponocephala electra). Additionally, 3 humpback whales (Megaptera noveangliae) were tagged in concert with this effort to test new tags, and that data was also analyzed herein

Statistical Analysis of Marine Mammal Stranding Events

This report documents the Naval Information Warfare Center (NIWC) Pacific Whale Acoustic Reconnaissance Project (WARP) Laboratory’s marine mammal monitoring efforts in fiscal year (FY) 2024 for Commander, Pacific Fleet (COMPACFLT) at the Pacific Missile Range Facility (PMRF), Kaua‘i, Hawai‘i.

Passive acoustic monitoring was conducted in the Navy’s Southern California (SOCAL) Range Complex from August 2023 to December 2024 in four locations to detect marine mammal and anthropogenic sounds. A new monitoring site was established offshore Morro Bay. Four CalCOFI cruises were conducted from fall 2023 to summer 2024 and included a total of 86 days at sea. Several active research projects within our lab group utilize data from sites funded by the Navy, contributing to significant advancements in marine mammal acoustics and ecosystem monitoring. In 2024 alone, these projects have resulted in multiple publications and conference presentations.

This document represents a brief annual summary on work completed between January 1st, 2024 to December 15th, 2024, under award N66604-22-D-F200, which is part of a broad project to monitor the populations of goose-beaked whales (Ziphius cavirostris) and fin whales (Balaenoptera physalus) in the Southern California Testing and Training Range (SCTTR).

Chinook salmon is an iconic species found throughout the North Pacific Ocean, yet little is known about its ocean ecology. The U.S. Navy conducts training exercises in the Gulf of Alaska (GOA) Temporary Maritime Activities Area (TMAA), and Western Maneuver Area (WMA). The Navy is interested in understanding the overlap of occurrence between populations of Chinook salmon and these training activities. To provide insights into Chinook salmon ocean ecology while occupying waters of the North Pacific Ocean (NPO), including overlap with the TMAA and WMA, we have previously deployed 183 pop-up satellite archival tags (PSATs) on Chinook salmon at eight locations around the GOA, and collected tissue samples to determine stock of origin of tagged fish. These analyses will provide additional insights into movement, depth distribution, temperature occupancy, and natural mortality of Chinook salmon in the North Pacific Ocean, particularly to the west of previous tag deployments.

Characterizing Behavior Distribution Salmonids Whales Offshore Marine Waters Washington

The Southern distinct population segment (sDPS) of green sturgeon Acipenser medirostris is federally listed as a threatened species under the United States (U.S.) Endangered Species Act (ESA). Large aggregations of both the Northern distinct population segment (nDPS) and sDPS of green sturgeon can be found congregating in Washington’s coastal estuaries mid-summer. This provides a unique opportunity to capture and study this elusive species. Existing telemetric data indicates that these fish make long migrations along the Pacific Coast with a possible year-round presence in near-shore marine waters along Washington and Oregon’s coastline. The U.S. Navy is interested in the occurrence of the threatened sDPS of green sturgeon in the Northwest Training and Testing (NWTT) study area (offshore of Washington, Oregon, and northern California).

This project provides financial support for comprehensive stranding investigations in order to obtain increased baseline information about the health of marine mammals. Such support is essential when considering the Pacific Islands region (PIR) where unique geographical challenges exist. The PIR is comprised of isolated islands, spanning over 4 million square miles across the North, South and Western Pacific basins and includes the Hawai‘i Range Complex and the Mariana Islands Range Complex. Cetacean stranding investigative efforts for the PIR are centralized at a dedicated stranding facility located at Marine Corps Base Hawai‘i (MCBH). This specialized facility houses the University of Hawai‘i (UH) Health and Stranding Lab, which plays a critical role as the only organization in the region to conduct cause of death investigations when dolphins and whales strand. This requires established relationships with partners throughout the region and the mounting of an immediate response to each newly reported stranding event that occurs. The UH Health and Stranding Lab conducts extensive necropsy examinations, including histopathology, disease surveillance, and tissue sampling in support of numerous research efforts aimed at better understanding Hawaiian cetaceans. In addition to this project facilitating advanced diagnostics in-house at the Health and Stranding Lab, we also report on progress towards a project option to measure fecal stress and reproductive hormones in Pacific Island cetaceans. An additional project option includes characterizing marine debris ingestion by abundance and mass in previously stranded short-finned pilot whales. Progress associated with the project option in support of the marine debris analyses has been prepared for peer-reviewed publication in the journal Marine Pollution Bulletin. These findings are described separately from the base tasks and fecal hormones option in the attached manuscript draft.

The University of Hawai‘i Health and Stranding Lab located at Marine Corps Base Hawaii (MCBH) is the only entity in the Pacific Islands region that responds to strandings, conducts necropsy and cause of death investigations, archives tissues and performs research to identify and evaluate threats to Pacific Island cetaceans. This project focuses on increasing our understanding of infectious diseases in the Pacific Island region by investigating the diseases caused by beaked whale circovirus (BWCV), cetacean morbillivirus (CeMV) and toxoplasmosis infections in cetaceans.

The Alaska Fisheries Science Center (AFSC), NOAA Fisheries, with support from the U.S. Navy, conducted line transect surveys in Behm Canal and adjacent areas in the spring of 2023 and fall of 2024 to obtain estimates of density and abundance of cetaceans and information on marine mammal distribution and occurrence.

NOAA Fisheries Science Centers have recently incorporated drifting acoustic spar buoy recorders (DASBRs) into their standard large-scale survey designs. Drifting autonomous instruments have many advantages, especially for species that are difficult to see at the surface, are vocal at depth, and whose sounds have been well characterized such that they can be readily identifiable from autonomous recordings. Pacific Islands Fisheries Science Center deployed DASBRs throughout the survey region with the goal of collecting data on the occurrence of beaked whales and other cryptic deepdivers. Traditional line-transect assessments for those species are often challenged by very low encounter rates, resulting in density and abundance estimates with high uncertainty, or in some cases, no estimates if groups were not seen during the ‘on-effort’ portions of the survey. Previous experience in the Marianas suggested that encounter rates for beaked whales on the DASBRs would be orders of magnitude higher within the DASBR data than in the visual survey or towed array datasets, likely enabling examination of density for some beaked whale species using the newly developed methods of Barlow et al. (2021a). Here, we detail our methodology to estimate density and abundance using 2021 survey dataset and how 2018 survey data were used to inform the detection parameters. This analysis has resulted in the first preliminary acoustic density and abundance estimates for Cuvier’s and Blainville’s beaked whales in the Mariana Islands region.

As part of the long-term United States (U.S.) Navy-funded Marine Species Monitoring Program, from 11–19 February 2024, Cascadia Research Collective (CRC) carried out a vessel-based field effort in conjunction with passive acoustic monitoring undertaken by the U.S. Navy (Navy) scientists on and around the underwater hydrophone ranges of the Pacific Missile Range Facility (PMRF). The effort was timed to occur immediately prior to the start of a Submarine Command Course (SCC) to allow for collection of movement and dive data that could be used to examine exposure and response of cetaceans to Navy mid-frequency active sonar (MFAS; see Henderson et al. 2021). Eight days of field effort were funded by the Navy, and one day of field work was funded by National Oceanic and Atmospheric Administration (NOAA) Fisheries. Wildlife Computers SPLASH10-F satellite tags were funded by the Navy for deployment on Navypriority species, and additional tags were provided by Wildlife Computers or CRC for deployment on other species (e.g., humpback whales [Megaptera novaeangliae]). Tags were programmed to collect dive behavior and Fastloc®-Global Positioning System (GPS) data from the time deployed until three and a half days after the end of the SCC and continue to transmit the dive and Fastloc®-GPS data for an additional six days. Starting on either May 2nd or May 3rd, the tags were duty cycled to transmit only every second day, to provide longer-term tracks of individual movements. During the period that tags were collecting dive and Fastloc®-GPS data, tags were programmed to try to obtain Fastloc®-GPS locations only for the 12 hours of the day when there were no or limited satellite overpasses. This programming change from previous Kauaʻi field efforts was taken to minimize temporal gaps in location data during the period that overlapped with and immediately followed the SCC. Field efforts were undertaken out of Kikiaola small boat harbor when conditions allowed for working on or near PMRF, or out of Port Allen when conditions on or near PMRF were not workable.

Three subsurface passive acoustic moorings were deployed in the western Gulf of Alaska on the EcoFOCI fall mooring cruise onboard the F/V Aquila 15 Aug – 14 Sep 2023; recovery is planned for September 2024, funding permitting. These mooring will allow investigation into the seasonal occurrence of many species of vocalizing marine mammals including North Pacific right (NPRW), blue, fin, humpback, minke, gray, sperm, killer, and beaked whales, Dall’s and harbor porpoise, general pinniped sounds, and anthropogenic noise sources such as vessels and seismic airguns. This is important data that the Navy needs to prepare environmental planning documentation, including those for the National Environmental Policy Act (NEPA), Marine Mammal Protection Act (MMPA), and ESA documents and consultations. It is also needed to inform the National Marine Fisheries Service Alaska Regional Office’s NPRW critical habitat expansion decision. In addition to the field work, processing of existing passive acoustic recordings from three moorings in the WGOA is ongoing, with one site (Barnabus Trough) completed for the high-frequency band. Killer whale vocalizations were detected on 214 of the 358 days with recordings.

This survey implemented visual line transect and passive acoustic methods to assess the presence and distribution and to estimate density and abundance of cetaceans in Behm Canal and central Clarence Strait.

In the Pacific, the Marine Mammal Monitoring on Navy Ranges (M3R) program maintains systems that continuously run algorithms to detect, classify and localize marine mammals year-round on the U.S. Navy’s deep-water Southern California Antisubmarine Warfare Range (SOAR) in Southern California and the Pacific Missile Range Facility (PMRF) off Kaua‘i, Hawai‘i. Long-term archive data collected on these ranges allow for numerous types of studies on species inhabiting the ranges, including the monitoring of abundance, behavioral responses to naval activities, and habitat usage. They also provide the opportunity to study ambient sound levels and soundscapes.

Understanding the spatio-temporal movements of animals is an integral component of wildlife conservation and management. Sea turtles are species of conservation concern and satellite telemetry is a primary research tool used to study their movements, providing high accuracy location data in near “real time,” thus facilitating rapid identification of movements and key habitats.

This report summarizes the results of satellite-tagging efforts conducted before Submarine Command Course (SCC) training events in August 2021 and 2022, at the Pacific Missile Range Facility (PMRF) off the island of Kauaʻi. Researchers tagged 21 delphinids to observe their behavior before, during, and after the SCCs, to estimate received levels (RLs) of mid-frequency active sonar (MFAS).

Tagging of cetaceans on or near active U.S. Navy training ranges provides for opportunistic behavioral response studies as the animals are exposed to real-world Navy training and testing activity, as compared to short duration-controlled exposure studies. Four Blainville’s beaked whales were satellite-tagged on the Pacific Missile Range Facility (PMRF) off the island of Kaua‘i in the Hawaiian Islands in 2014, 2021, and 2022. The animal tagged in 2014 left the area immediately, but their tag data still provides useful baseline information of behavior and habitat use in the area. Two Blainville’s beaked whales were tagged from the same group in 2021. They remained together and were highly synchronized in their dive and movement behavior until the onset of mid-frequency active sonar (MFAS), at which time the whales appeared to separate. The dive behavior of the two animals tagged in 2021 were compared to acoustically detected group vocal periods (GVPs) on the range; 23 deep foraging dives were matched to GVPs, including three during MFAS exposures from three sources: hull-mounted MFAS, active sonobuoys, and helicopter-dipping MFAS.

The U.S. Navy conducts military training and testing in Pacific Northwest range areas to prepare combat-ready military forces, whereas NOAA Fisheries is responsible for managing threatened and endangered species in marine waters and providing permits to the U.S. Navy. NOAA Fisheries and the U.S. Navy share the common goals of minimizing the impact of military training and testing activities on endangered species without compromising training and testing efforts and reducing adverse environmental effects. This work provides vital geographic and distributional data within the Navy’s range areas, allowing the Navy the flexibility to proceed with training and testing while providing protective measures for both salmonids and killer whales. This research jointly studied Chinook salmon and Southern Resident killer whales (SRKW) in the Northwest Training and Testing (NWTT study area) Range. The authors used acoustic telemetry to map salmon behavior and overlap with SRKW occurrence. By tracking Chinook salmon, SRKW's primary prey, the project aims to guide actions to conserve both species. The data will help adjust activities to minimize harm to these protected species. From May to September 2023, 101 Chinook salmon were caught, tagged, and released north of the Columbia River near the Washington Coast. Acoustic transmitters were surgically implanted into the fish, allowing them to be detected by stationary receivers deployed in the ocean, estuaries, and nearby rivers. The fish's locations and movements were recorded and used to Submitted in Support of the U.S. Navy’s 2023 Annual Marine Species Monitoring Report for the Pacific STANDARD FORM 298 Back (Rev. 8/98) assess their spatial distribution and behavior. SRKW detections were also collected from March to October 2023 at 15 passive acoustic moorings on the Washington coast. These acoustic moorings, in combination with the 69 kHz receivers, are currently in operation. All but one of the salmon tagged so far were Snake River spring/summer Chinook ESU and the remaining Chinook origin is yet to be determined. Tasks the are still to be completed include tagging an estimated 60 Chinook salmon and analyzing concurrently collected SRKW data. Spring-run Chinook salmon that are returning to the Columbia River are b

A total of six Rockhopper passive acoustic recording units were deployed off the west coast of Guam in the Mariana Islands Training and Testing (MITT) study area to acoustically monitor beaked whales and mid-frequency active sonar (MFAS). Five units were deployed in an array configuration with a 1 kilometer (km) baseline in the northern part of the survey area to locate beaked whale echolocation clicks and derive a probability of detection function necessary for estimating density. An additional sixth unit was deployed approximately 15 km south of the array to investigate spatiotemporal variability in beaked whale encounters in the survey area.

This report documents the Naval Information Warfare Center (NIWC) Pacific Whale Acoustic Reconnaissance Project (WARP) Laboratory’s marine mammal monitoring efforts in fiscal year (FY) 2023 for Commander, Pacific Fleet (COMPACFLT) at the Pacific Missile Range Facility (PMRF), Kaua‘i, Hawai‘i.

Passive acoustic monitoring was conducted in the Navy’s Southern California (SOCAL) Range Complex from May 2022 to July 2023 to detect marine mammal and anthropogenic sounds. High-frequency Acoustic Recording Packages (HARPs) recorded sounds between 10 Hz and 100 kHz at four locations: one site west of San Nicolas Island (1,100 m depth, site SN), two sites west of San Clemente Island (1,300 m depth, site E and 1,200 m depth, site H), and one site southwest of San Clemente Island (1,300 m depth, site N) to improve noise monitoring for the SOCAL range.

The Southern California Tactical Training Range (SCTTR), within the Hawaii-Southern California Training and Testing Area, is one of the United States Navy’s most heavily used regions, particularly for mid-frequency active sonar training. Much of the SCTTR lies within the Southern California Bight, a productive oceanographic region that hosts a wide variety of marine species. As part of ongoing studies of the distribution and demographics of several marine mammal species within the SCTTR, we conducted 24 days of survey effort from 7 January 2023 to 8 October 2023, specifically focusing on the Southern California Anti-submarine Warfare Range. The primary goal of these surveys was sighting, photographing, and collecting tissue samples from Cuvier’s beaked whales (Ziphius cavirostris) and fin whales (Balaenoptera physalus). With combined effort from two ancillary projects funded by the United States Navy’s Living Marine Resources program and the Office of Naval Research, we had 203 sightings of cetaceans, including 18 sightings totaling 41 Cuvier’s beaked whales and 37 sightings totaling 59 fin whales. Identification photographs from these sightings were combined with opportunistic contributions from both species for this and prior years. Identification photographs from these sightings were combined with opportunistic contributions from both species for this and prior years. This yielded a total of 52 unique Cuvier’s beaked whales in 2023, 15 (29%) of which had been sighted in a previous year. Two mother-calf pairs were photographed, one new to the study, the other had been seen four times prior to 2023 including as a subadult in 2010. We processed 436 new fin whale identifications through 2022, bringing that dataset to 3,620 sightings of 1,377 unique individuals. Eleven genetic samples were collected in 2023, eight from Submitted in Support of the U.S. Navy’s 2023 Annual Marine Species Monitoring Report for the Pacific STANDARD FORM 298 Back (Rev. 8/98) Cuvier’s beaked whales and three from common dolphins. Nine satellite tags were deployed: six SMRT tags on Cuvier’s; one SMRT and two LIMPET tags on fin whales.

Chinook salmon (Oncorhynchus tshawytscha) is an iconic species found throughout the North Pacific Ocean (NPO) and supports valuable subsistence, commercial and recreational fisheries. In addition to its importance to fisheries, Chinook salmon is an important food source for many apex marine predators, including endangered Southern Resident killer whales (Orcinus orca). Currently, coast-wide changes in Chinook salmon population demographics and production have been documented from western Alaska to California, including several Evolutionarily Significant Units (ESUs) from the United States (U.S.) Pacific Northwest (PNW) that are protected under the U.S. Endangered Species Act (ESA). The U.S. Navy (Navy) conducts at-sea training in the Gulf of Alaska (GOA), including in the Temporary Maritime Activities Area (TMAA) and the Western Maneuver Area (WMA). As part of its Marine Species Monitoring Program, the Navy is interested in understanding the overlap of occurrence between populations of Chinook salmon, particularly the ESUs that are listed under the ESA, and specific Navy training activities. This is challenging, as relatively little is known about the at-sea distribution and behavior of Chinook salmon, despite the fact that most individuals reside in the ocean for the majority of their lives. Therefore, an improved understanding of the distribution and behavior of Chinook salmon in the marine environment is important when addressing potential interactions between this species and specific Navy exercises within portions of the TMAA and WMA.

The migration route and timing of Chinook salmon along the coast of Washington State is not well understood. To determine when and where Chinook salmon of different genetic stocks enter and transit through the U.S. Navy Northwest Training and Testing Area (NWTT), we tagged 298 maturing adult salmon across five locations throughout the Gulf of Alaska.

This project provides support for comprehensive stranding investigations in order to obtain increased baseline information about the health of marine mammals. Such support is essential when considering the Pacific Islands region (PIR) where unique geographical challenges exist. The PIR is comprised of isolated islands, spanning over 4 million square miles across the North, South and Western Pacific basins and includes the Hawai‘i Range Complex and the Mariana Islands Range Complex. All cetacean stranding response and investigative efforts for the PIR are centralized at a dedicated stranding facility located at Marine Corps Base Hawai‘i (MCBH). This specialized facility houses the University of Hawai‘i (UH) Health and Stranding Lab, which plays a critical role as the only organization in the region to conduct cause of death investigations when dolphins and whales strand. This requires mounting an immediate response to each newly reported stranding event that occurs and conducting extensive necropsy examinations, including histopathology, disease surveillance, and tissue sampling in support of numerous research efforts aimed at better understanding Hawaiian cetaceans. In addition to this project facilitating advanced diagnostics in-house at the Health and Stranding Lab, we also report on progress towards a project option to measure fecal stress and reproductive hormones in Pacific Island cetaceans. An additional project option includes characterizing marine debris ingestion by abundance and mass in previously stranded short-finned pilot whales.

We report significant pathological findings from 250 stranding investigations of 20 cetacean species in the Pacific Islands region between 2006 and 2022. Full or partial necropsies of 196 of the 250 stranding cases (78.4%) resulted in a diagnosis or multiple diagnoses associated with death in 126 cases. Natural disease accounted for 60.3% of stranded animals; approximately half were in poor body condition at time of death due to chronic illness. Morbillivirus and Brucella sp. infections caused mortality in eleven species, including striped dolphins and the Longman’s beaked whale. Toxoplasma infection, of anthropogenic cause in Hawaiʻi, led to the deaths of two spinner dolphins. Pygmy and dwarf sperm whales, beaked whales and pilot whales showed heavy parasitism by nematodes, cestodes and trematodes. Approximately 12.7% of stranded individuals were perinates/neonates, with three cases of dystocia with maternal mortality. Anthropogenic trauma was observed in 30.2% of strandings. In seven Cuvier’s beaked whales, cranial and/or microvascular hemorrhages were categorized as trauma. Vertebral and skull fractures were attributed to direct vessel strikes for two pygmy sperm whales, a Cuvier’s beaked whale, a humpback whale calf and a striped dolphin. Blast trauma was observed in three Fraser’s dolphins that were part of an uncommon stranding event. Significant plastic debris, and/or fishery debris were found in stomachs of six species and fatal fishhook penetration occurred in a Submitted in Support of the U.S. Navy’s 2023 Annual Marine Species Monitoring Report for the Pacific STANDARD FORM 298 Back (Rev. 8/98) bottlenose dolphin. This study highlights the value of carcass examinations in a region inhabited by small island associated populations where carcass recovery rates are low, and cetaceans face an array of natural and anthropogenic threats.

Beaked whales are a group of deep diving whales with a world-wide distribution that consists of six genera and 24 identified species. Many species of beaked whales are rarely observed alive at sea and almost all biological data for the most poorly described species is based on stranding events. We examined beaked whale strandings across the western, central and southern Pacific, an area of more than 40 million square kilometers that encompasses island nations and territories in Polynesia, Micronesia and Melanesia. Confirmed strandings of beaked whales include specimens that represent five different species.

The University of Hawaii Health and Stranding Lab located at Marine Corps Base Hawaii (MCBH) is the only entity in the Pacific Islands region that responds to strandings, conducts necropsy and cause of death investigations, archives tissues and performs research to identify and evaluate threats to Pacific Island cetaceans. This project focuses on increasing our understanding of infectious diseases in the Pacific Island region by investigating the emerging diseases caused by circovirus, morbillivirus, herpesvirus and toxoplasmosis infections in cetaceans.

This review examines historical data from 535 odontocete stranding events in the Mariana archipelago and Hawaiian Islands by date, location and species and spans the time period of 1848 to 2023. Reports of strandings increased across the two geographic regions that were generally consistent over time. A total of 54 historical stranding events that represent 14 odontocete species are described for the Mariana Islands. A total of 481 stranding events that represent 19 odontocete species are described from the Hawaiian Islands, significantly updating the last published report that examined 202 odontocete strandings that occurred in the main Hawaiian Islands between 1937 and 2002. ArcGIS cluster maps were utilized to identify groupings of stranding events across the geographic regions. The majority of strandings in the Mariana Islands were reported from the west and southeastern coast of Guam, followed by Saipan, Rota and Tinian. Stranding hotspots in the Hawaiian Islands were identified at Mā’alaea Bay, Maui, at windward Oʻahu and near Kailua-Kona on Hawaiʻi Island.

Status report for the acoustic and visual survey for cetaceans in Behm Canal and Southern Clarence Strait, Alaska, FY22.

As part of the long-term United States (U.S.) Navy-funded Marine Species Monitoring Program, from 16–24 August 2022, Cascadia Research Collective (CRC) carried out a vessel-based field effort in conjunction with passive acoustic monitoring undertaken by U.S. Navy (Navy) scientists on and around the underwater hydrophone ranges of the Pacific Missile Range Facility (PMRF).

As part of the long-term United States (U.S.) Navy-funded Marine Species Monitoring Program, from 5-13 August 2023, Cascadia Research Collective (CRC) carried out a vessel-based field effort in conjunction with passive acoustic monitoring undertaken by U.S. Navy (Navy) scientists on and around the underwater hydrophone ranges of the Pacific Missile Range Facility (PMRF).

For the last five months, Dr. Will Gough has been working at the Marine Mammal Research Program (MMRP) on a number of goals that will build capacity within Hawaii and advance the Navy’s goals related to the long-term health of protected marine mammal species. These goals relate to Dr. Gough’s expertise working with accelerometry-based biologging tags and include: setting up infrastructure at the MMRP to maintain large quantities of tag data, collecting novel data and expanding existing datasets through field efforts, training members of the Navy and MMRP to work effectively with accelerometry data and biologging devices, develop training materials and short-form workshops to disseminate knowledge of accelerometry data processing and analysis more broadly within the Hawaiian community, and use new and existing datasets to answer questions of relevance to the Navy and other organizations tasked with monitoring and management of protected species.

In the Pacific the Marine Mammal Monitoring on Navy Ranges (M3R) program maintains systems that continuously run algorithms to detect, classify and localize marine mammals year-round on the U.S. Navy’s deep-water Southern California Antisubmarine Warfare Range (SOAR) in Southern California and Pacific Missile Range Facility (PMRF) off Kauai, Hawai’i. Long-term archive data collected on these ranges allows for numerous types of studies on species inhabiting the ranges, including the monitoring of abundance and distribution, behavioral responses to naval activities, and habitat usage. They also provide the opportunity to study ambient noise and soundscapes.

The Southern distinct population segment (sDPS) of green sturgeon Acipenser medirostris is federally listed as a threatened species under the United States (U.S.) Endangered Species Act (ESA). Large aggregations of both the Northern distinct population segment (nDPS) and sDPS of green sturgeon can be found congregating in Washington’s coastal estuaries mid-summer. This provides a unique opportunity to capture and study this elusive species. Existing telemetric data indicates that these fish make long migrations along the Pacific Coast with a possible year-round presence in near-shore marine waters along Washington and Oregon’s coastline. The U.S. Navy is interested in the occurrence of the threatened sDPS of green sturgeon in the Northwest Training and Testing (NWTT) study area, which is offshore of Washington, Oregon, and northern California.

In September 2023, a third multi-week expedition was conducted off the coast of Baja California, Mexico to relocate the unknown species of beaked whales encountered in 2020 as well as look for the BW43 beaked whale. Daily non-systematic searches were carried out close to shore off Bahia San Quintín

This report documents Naval Information Warfare Center Pacific (NIWC Pacific) marine mammal monitoring efforts in fiscal year (FY) 2022 for Commander, Pacific Fleet (COMPACFLT) at the Pacific Missile Range Facility (PMRF), Kaua'i, Hawai

Coral reef surveys were conducted at Farallon de Medinilla (FDM) August 14–19, 2022 by Naval Information Warfare Center (NIWC) Pacific Scientific Diving Services (SDS) to satisfy requirements of the Mariana Islands Training and Testing Area Biological Opinion (MITT BO) issued by the National Marine Fisheries Service in 2020 (NMFS 2020). This report fulfills portions of Terms and Conditions (T&C) 2b and 2c of the 2020 MITT BO (NMFS 2020). T&C 2b includes the requirement for the Navy to “provide reports of any observed inwater effects (e.g., crater size, observed mortality) to corals resulting from detonations of high-explosive ordnance as they are discovered...during coral reef surveys...” T&C 2c states “The Navy shall, no less than once every five years, survey coral reef habitat around FDM within 30 m of water depth. These surveys will be structured to confirm presence or absence and abundance of Endangered Species act (ESA)-listed corals and to assess general trends in coral reef species composition, percent coral coverage, and condition (disease, predators, extent of breakage, etc.).” The primary objectives of the 2022 field survey were to quantify the abundance and location around the island of ESA-listed corals, quantify coral reef health (percent cover of living coral, coral species composition, and coral condition), and compile observations of ordnance impacts. Secondary objectives were to record incidental observations of any other ESA-listed species encountered while fulfilling the primary objectives.

NOAA Fisheries Science Centers have increasingly relied on passive acoustic datasets to augment traditional visual‐based assessments with recent efforts including drifting recorders (DASBRs) resulting in beaked whale habitat preferences in the Mariana Archipelago and first‐ ever acoustic‐based density and abundance estimates for Cuvier’s beaked whales along the entire US west coast. In 2021 the Navy supported line‐transect survey for cetaceans throughout the Mariana Archipelago and throughout the large‐scale survey effort DASBRs were deployed with the goal of collecting data on the occurrence of beaked whales and other cryptic deep‐ divers.

Passive acoustic monitoring was conducted in the Navy’s Southern California Range Complex from April 2021 to May 2022 to detect marine mammal and anthropogenic sounds. High-frequency Acoustic Recording Packages (HARPs) recorded sounds between 10 Hz and 100 kHz at four locations: one site west of San Nicolas Island (1,100 m depth, site SN), two sites west of San Clemente Island (1,300 m depth, site E and 1,200 m depth, site H), and one site southwest of San Clemente Island (1,300 m depth, site N). With the offshore expansion of the SOCAL range, site SN was added into the monitoring effort for this reporting period to improve noise monitoring for the region.

Three different killer whale (Orcinus orca) ecotypes are known to inhabit the northeastern Pacific: residents, transients, and offshores. These ecotypes are distinguished by morphological, genetic, behavioral, and acoustic differences. Killer whales of each ecotype produce distinct, stereotypic pulsed calls that can be used as acoustic indicators of presence, making passive acoustic monitoring a useful method for assessing intraspecies differences in spatial and temporal patterns.

Analysis of scat samples from animals is a non‐invasive technique that can provide important data on animal diet, hormone levels, microbiome, and genetics. The use of a trained Conservation Canine (K9) to detect marine mammal scat at sea has been proven to be useful in the Pacific Northwest with Southern Resident Killer Whales (Lundin et al. 2016) and in other unpublished reports and media, but until now, had not been documented in Hawaii. In order to explore the viability of this method in Hawaii, the Navy invested in a pilot study, where the K9 was successfully trained to detect and ‘direct’ boat drivers – via changes in behavior – to the scat of three species of marine mammals (G. macrorynchus, K. breviceps, and P. crassidens).

The Southern California (SOCAL) portion of the Hawaii-Southern California Training and Testing (HSTT) area (SOCAL TR) is one of the United States Navy’s most active training areas, particularly for mid-frequency active sonar (MFAS). Much of SOCAL lies within the Southern California Bight, a productive oceanographic region that hosts a wide variety of marine species. As part of an ongoing study of the distribution and demographics of several marine mammal species within SOCAL, we conducted 32 days of survey effort from 6 January 2022 to 26 November 2022, specifically focusing on the Southern California Anti-submarine Warfare Range (SOAR).

Chinook salmon (Oncorhynchus tshawytscha) is an iconic species found throughout the North Pacific Ocean and supports valuable subsistence, commercial and recreational fisheries. In addition to its importance to fisheries, Chinook salmon is an important food source for many apex marine predators, including endangered Southern Resident killer whales (Orcinus orca). Currently, coast-wide changes in Chinook salmon population demographics and production have been documented from western Alaska to California, including several Evolutionarily Significant Units (ESUs) from the United States (U.S.) Pacific Northwest (PNW) that are protected under the U.S. Endangered Species Act (ESA).

This study aims to improve the understanding of the extent to which bull trout (Salvelinus confluentus), a threatened species, exhibit anadromous behavior or migrate between freshwater and saltwater environments, between coastal rivers on the Olympic Peninsula in Washington state and adjacent to the Navy’s Northwest Training and Testing (NWTT) Study Area

Three acoustic tag glider deployments were conducted in Washington's (WA) coastal portion of the Northwest Training and Testing (NWTT) Study Area between September 2019 and June 2020. This survey was conducted with funding from the U.S. Navy Pacific Fleet to determine the utility of glider-based acoustic tag detection in a highly mobile fish, Chinook salmon. The primary objective was to expand the detection range of a U.S. Navy-funded stationary, moored acoustic tag receiver array by extending the detection beyond the shelf edge and in other deeper locations, such as marine canyons where the moored acoustic receiver units were not feasible to deploy.

The migration route and timing of Chinook salmon along the coast of Washington State is not well understood. To determine when and where Chinook salmon of different genetic stocks enter and transit through the U.S. Navy Northwest Training and Testing Area (NWTT) we tagged 298 maturing adult salmon across five locations throughout the Gulf of Alaska.

Steelhead trout populations have been declining along Washington State's coast, with limited information about their ocean distribution and movement timing. Steelhead can travel long distances and spawn multiple times, with repeat spawners being more productive. In this study, the authors aimed to understand post-spawn steelhead movements using acoustic telemetry and pop-up satellite tags (PSAT) to determine the location and timing of winter-run steelhead within the Northwest Training and Testing (NWTT) area in 2021. Acoustic telemetry showed that 73.5% of wild fish tagged during their upstream migration died on or near spawning grounds.

This project provides support for comprehensive stranding investigations in order to obtain increased baseline information about the health of marine mammals. Such support is essential when considering the Pacific Islands region (PIR) where unique geographical challenges exist. The PIR is comprised of isolated islands, spanning over 4 million square miles across the North, South and Western Pacific basins and includes the Hawai‘i Range Complex and the Mariana Islands Range Complex.

The University of Hawaiʻi Health and Stranding Lab, located at Marine Corps Base Hawaiʻi (MCBH), is the only entity in the Pacific Islands region that responds to strandings, conducts necropsy and cause of death investigations, archives tissues and performs research to identify and evaluate threats to Pacific Island cetaceans. The purpose of this project is to conduct analyses of historical stranding patterns and causes of mortality that incorporate quantitative estimates of stranding dates, genetic identification of species when necessary, and advanced laboratory diagnostics.

In this study, we conducted line transect surveys to assess the seasonal distribution and abundance of marine mammals in Hood Canal (Washington), with emphasis on harbor porpoises (Phocoena phocoena) and killer whales (Orcinus orca).

As part of the long-term United States (U.S.) Navy-funded Marine Species Monitoring Program, from 1-14 August 2021, a combination of boat-based field effort and passive acoustic monitoring was carried out on and around the underwater hydrophone ranges of the Pacific Missile Range Facility (PMRF).

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).

In the Pacific the Marine Mammal Monitoring on Navy Ranges (M3R) program maintains systems that automatically detect, classify and localize marine mammals in real-time on the U.S. Navy’s deep-water Southern California Antisubmarine Warfare Range (SOAR) in Southern California and Pacific Missile Range Facility (PMRF) off Hawai’i. Long-term archive data collected on these ranges allows for numerous types of studies on species inhabiting the ranges, including the monitoring of abundance and distribution, behavioral responses to naval activities, and habitat usage. They also provide the opportunity to study ambient noise and soundscapes.

In 2013, under an inter-agency agreement (IAA) between the United States Navy and the National Oceanic and Atmospheric Administration (NOAA), NOAA began conducting in-water surveys to record and quantify observations of marine turtles around the Mariana Archipelago. When observed, attempts were made to hand-capture turtles and equipthem with satellite tags in an effort to better understand their spatial ecology.

Autonomous passive acoustic recorders have been used for the past 15 years to monitor the coastal occurrence of Southern Resident killer whales (SRKW), other marine mammals, and anthropogenic noise in and adjacent to the Navy’s NWRTC in Washington State. The five autonomous acoustic recorders in and adjacent to the Navy’s NWTRC were successfully recovered in early September 2021 and new moorings were redeployed at each site.

The Southern distinct population segment (DPS) of green sturgeon Acipenser medirostris is federally listed as a threatened species under the U.S. Endangered Species Act (ESA). Large aggregations of both the Northern DPS and Southern DPS of green sturgeon can be found congregating in Washington’s coastal estuaries mid-summer. This provides a unique opportunity to capture and study this elusive species. Existing telemetric data indicates that these fish make long migrations along the Pacific Coast with a possible year-round presence in near-shore marine waters along Washington and Oregon’s coastline. The U.S. Navy is interested in the occurrence of the threatened Southern DPS of green sturgeon in the Northwest Training and Testing (NWTT) study area, which is offshore of Washington, Oregon, and northern California.

An expedition was conducted with the goal of visually locating, acoustically recording, and obtaining biopsy samples of the Mesoplodon beaked whales that were encountered in 2020 and produce BWB pulses, as well as locating the beaked whales that produce the BW43 echolocation pulse in order to conclusively determine what species produce each of the pulse types.

This report documents Naval Information Warfare Center (NIWC) Pacific marine mammal monitoring efforts in fiscal year (FY) 2021 for Commander, Pacific Fleet (COMPACFLT) at the Pacific Missile Range Facility (PMRF), Kaua‘i, Hawai‘i.

The United States (US) Navy uses lookouts (LOs) to detect objects in the water in the vicinity of ships. One class of object that LOs are trained to detect is marine mammals ; this forms an important component of the Navy’s procedures for marine mammal mitigation during training activities . As well as dedications of marine mammals by these LOs, detections of marine mammals may also be made by other members of the ship’s crew such as officers on the bridge (“watchstanders”) or sonar technicians, although acoustic detections require visual confirmation. We refer to these personnel together as the “lookout team” (LT). The primary goal of this project was to determine how effective LTs are at detecting marin

Passive acoustic monitoring was conducted in the Navy’s Southern California Range Complex from April 2020 to 2021 to detect marine mammal and anthropogenic sounds. High-frequency Acoustic Recording Packages (HARPs) recorded sounds between 10 Hz and 100 kHz at four locations: two west of San Clemente Island (1,300 m depth, site E and 1,100 m depth, site H) and two southwest of San Clemente Island (1,300 m depth, site N and 1,200 m depth, site U). With the offshore expansion of the SOCAL range, future noise monitoring will be improved by the deployment of a recorder west of San Nicolas Island (site SN). This new site will replace site U, which is located in the Mexican Exclusive Economic Zone where instrument deployment is difficult.

As part of an ongoing study of the distribution and demographics of several marine mammal species within SOCAL, we conducted 17 days of survey effort from 3 September 2021 to 15 November 2021, specifically focusing on the Southern California Anti-submarine Warfare Range (SOAR). The primary goal of these surveys was sighting, photographing, and collecting biopsy samples from Cuvier’s beaked whales (Ziphius cavirostris) and fin whales (Balaenoptera physalus).

The information about Chinook salmon gained in this study may be used to provide insights into important management issues in the North Pacific Ocean, including overlap between Chinook salmon and Navy training exercises in the GOA.

The Northwest Fisheries Science Center is currently conducting a study to characterize the occurrence of Chinook salmon within the Northwest Training and Testing area (NWTT).

This project provides support for comprehensive stranding investigations in order to obtain increased baseline information about the health of marine mammals. Such support is essential when considering the Pacific Islands region (PIR) where unique geographical challenges exist.

The University of Hawaii Health and Stranding Lab located at Marine Corps Base Hawaii (MCBH) is the only entity in the Pacific Islands region that responds to strandings, conducts necropsy and cause of death investigations, archives tissues and performs research to identify and evaluate threats to Pacific Island cetaceans (dolphins, whales, and porpoises).

The University of Hawaii Health and Stranding Lab located at Marine Corps Base Hawaii (MCBH) is the only entity in the Pacific Islands region that responds to strandings, conducts necropsy and cause of death investigations, archives tissues and performs research to identify and evaluate threats to Pacific Island cetaceans. The purpose of this project is to conduct analyses of historical stranding patterns and causes of mortality that incorporate quantitative estimates of stranding date, genetic identification of species when necessary and advanced diagnostic procedures, including evaluation of nutritional state to categorize past strandings as acute or chronic causes.

Cetacean and Seabird Data During the Mariana Archipelago Cetacean Survey

As part of a long-term U.S. Navy-funded marine mammal monitoring program, in February 2020 a combination of vesselbased field effort and passive acoustic monitoring was carried out on and around the Pacific Missile Range Facility (PMRF) off Kaua‘i prior to a Submarine Command Course scheduled for mid-February 2020. The purpose of the monitoring effort was to assess the spatial movement patterns and habitat use of cetaceans that are exposed to midfrequency active sonar and how those patterns influence exposure and potentially responses. Results from this effort were compared with previous Cascadia Research Collective (CRC) survey effort and photo-identification and tag data from Kaua‘i, based on surveys in 11 different years since 2003.

In order for the U.S. military to conduct readiness training with the Mariana Island Training and Testing Study Area (MITT), including the area around Farallon de Medinilla (FDM), the Navy is required to monitor potential impacts of these activities on Marine Mammal Protection Act and Endangered Species Act-listed species. Humpback whales belonging to the North Pacific population are known to use portions of the MITT seasonally for breeding activities, specifically Marpi Reef and shallow waters around Saipan. A small-vessel visual survey for humpback whales was conducted between 29 January 2020 and 1 February 2020 to better understand the use of shallow-water habitat around FDM

In FY20 the M3R program had six areas of focus for SOAR and PMRF: 1) long‐term data collection and the evaluation of abundance and distribution of Cuvier’s beaked whales at SOAR and Blainville’s beaked whales at PMRF; 2) the effect of two types of mid‐frequency active sonar (MFAS), hull‐mounted and dipping sonar, on Cuvier’s beaked whales at SOAR and Blainville’s beaked whales at PMRF; 3) evaluation of the M3R low‐frequency detector algorithm at SOAR; 4) determination of Autogrouper detection statistics for Blainville’s beaked whales at PMRF; 5) the development of tools to automatically characterize the ambient noise at SOAR using archive files; and 6) the support of on‐site field exercises at SOAR and PMRF with real‐time monitoring using the M3R system.

A passive acoustic monitoring survey using mobile underwater gliders was conducted from 7 February to 31 March 2020 in the Southern California Bight, with the goal of characterizing the temporal and spatial distribution of odontocetes and mysticetes in the region. Initially, the focus of this Project was on beaked whales. However, upon recovery of the gliders post-deployment, it was discovered that neither glider recorded any useable data above 2.5 kilohertz, well below the frequency of beaked whale vocalizations. It was then decided to analyze the available data for baleen whale and sperm whale (Physeter macrocephalus) vocalizations, which was originally a focus of secondary importance for the Project.

The United States Navy developed monitoring questions for the Mariana Islands Training and Testing (MITT) study area under the Mariana Islands Range Complex Monitoring Plan (MIRCMP), including questions specifically related to marine turtles as required under the Endangered Species Act (ESA) of 1973. To support the needs of the U.S. Pacific Fleet Environmental Readiness Office, the Marine Turtle Biology and Assessment Program (MTBAP) of the National Oceanic and Atmospheric Administration (NOAA) has been conducting research on marine turtle abundance and spatial-temporal ecology in the nearshore waters of Saipan, Tinian, and Guam since 2013, under a series of Interagency Agreements (IAA).

Large aggregations of both the Northern distinct population segment (DPS) and ESA-listed Southern DPS of the green sturgeon Acipenser medirostris can be found congregating in Washington’s coastal estuaries mid-summer. This provides a unique opportunity to capture and study this elusive species. Existing telemetric data indicates that these fish make long migrations along the Pacific Coast with a possible year-round presence in near-shore marine waters along Washington and Oregon’s coastline. The U.S. Navy is interested in evaluating the impacts of military training and testing operations to protected species and, for the purpose of this project, is specifically interested in assessing impacts to the threatened Southern DPS of green sturgeon.

This report summarizes the development and application of substantially upgraded analytical methods to quantify the movement and diving behavior of satellite tagged odontocetes before, during, and after Submarine Command Course (SCC) training events at the Pacific Missile Range Facility (PMRF) off Kaua‘i, Hawai‘i, including their predicted exposure and potential response to mid-frequency active sonar (MFAS) during these events

This report summarizes the field effort from 15 – 28 November, 2020, to locate and document a species of beaked whales that had previously only been acoustically detected. While the species of interest was again recorded on acoustic drift buoys, a previously undescribed species of beaked whale was unexpectedly encountered instead. This new species has external morphological characteristics and a new echolocation pulse type that do not match any previously observed or recorded species and therefore may represent a newly described species. In addition to this species of beaked whale, we encountered and photographed three species of dolphin as well as humpback whales, and recorded two other species of beaked whales on the acoustic recorders.

This report documents Naval Information Warfare Center Pacific (NIWC Pacific) marine mammal monitoring efforts in fiscal year (FY) 2020 for Commander, Pacific Fleet (COMPACFLT) at the Pacific Missile Range Facility (PMRF), Kauai, Hawaii.

In February 2020, a passive acoustic monitoring (PAM) survey using Autonomous Underwater Vehicles (AUVs, aka “gliders”) was performed off Southern California using two Seagliders™ equipped with Passive Miniature Acoustic Recorder (PMAR)-XL acoustic processing boards, manufactured by Hydroid, Inc. (formerly a subsidiary of Kongsberg Marine, now a subsidiary of Huntington Ingalls Industries).

Information on green sturgeon occurrence in Puget Sound and the Strait of Juan de Fuca is needed to ensure that potentially harmful human actions do not impact this species, particularly the southern distinct population segment (DPS), which is listed as threatened under the U.S. Endangered Species Act. We reviewed acoustic detection data from 2002 to 2019 for incidence of acoustically tagged green sturgeon in these areas.

Since 2012, Oregon State University (OSU) has been conducting tagging and tracking studies on large whales in support of the U.S. Navy’s efforts to meet regulatory requirements for marine mammal monitoring under the Endangered Species Act and the Marine Mammal Protection Act. The primary goal of these studies has been to determine whale movement patterns, occurrence, and residence times within several Navy training and testing areas in the Pacific Ocean, as reported extensively in a series of previous Technical Reports

Passive acoustic monitoring was conducted in the Navy’s Southern California Range Complex from November 2018 to May 2020 to detect marine mammal and anthropogenic sounds. High-frequency Acoustic Recording Packages (HARPs) recorded sounds between 10 Hz and 100 kHz at four locations: two west of San Clemente Island (1,300 m depth, site E and 1,000 m depth, site H) and two southwest of San Clemente Island (1,250 m depth, site N and 1,200 m depth, site U).

The information about Chinook salmon gained in this study may be used to provide insights into important management issues in the North Pacific Ocean, including overlap between Chinook salmon and Navy training exercises in the GOA.

The Northwest Fisheries Science Center is currently conducting a study to characterize the occurrence of Chinook salmon within the Northwest Training and Testing area (NWTT).

The University of Hawai‘i Health and Stranding Lab (HSL), located in Kaneohe Bay, is the only entity in the Pacific Islands region that responds to strandings, conducts necropsy and cause of death investigations, archives tissues and performs research to identify and evaluate threats to Pacific Island cetaceans. The purpose of this project has three objectives: 1) To conduct comprehensive stranding investigations for high priority species through increased capacity for in-house diagnostics; 2) To analyze archived tissues for the presence of two pathogens (circovirus and morbillivirus) and to examine the detectability of Toxoplasma positive animals over time and 3) To conduct analyses of historical stranding patterns and causes of mortality that incorporate quantitative estimates of stranding date and advanced diagnostic information.

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).

Beaked whale abundance and vocal behavior were examined at two different U. S. Navy training ranges: for Cuvier’s beaked whale (Ziphius cavirostris) at the Southern California Anti-Submarine Warfare Range (SOAR) between August 2010 through October 2019, and for Blainville’s beaked whales (Mesoplodon densirostris) at the Pacific Missile Range Facility (PMRF) between 2015 and 2018. The yearly and monthly abundance, mean number of group vocal periods (GVPs), mean duration of the GVPs in minutes, and the mean number of clicks detected per beaked whale group were calculated.

Understanding the spatio-temporal movements of animals is an integral component of wildlife conservation and management. Marine turtles are species of conservation concern and satellite telemetry is a primary research tool used to study their movements, providing high accuracy location data in near “real time”, thus facilitating rapid identification of movements and key habitats.

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).

This report documents Naval Information Warfare Center Pacific (NIWC Pacific) marine mammal monitoring efforts in fiscal year (FY) 2019 for Commander, Pacific Fleet (COMPACFLT) at the Pacific Missile Range Facility (PMRF), Kauai, Hawaii.

This work is in support of marine species monitoring activities by the United States (US) Navy in its training and testing range complexes in the Pacific Ocean. Specifically, the study seeks to help delineate humpback whale Distinct Population Segments found off the US West Coast, as well as to describe their feeding-season home range, migration to the breeding areas, diving behavior, habitat use, and ecological characteristics.

Since 2007, visual and acoustic cetacean monitoring efforts in the Mariana Islands have documented the occurrence of humpback whales (Megaptera novaeangliae) during winter months. However, these efforts have focused mainly around the southern portion of the archipelago, in particular Saipan and Tinian. This report presents an analysis of passive acoustic data for humpback whale song near the islands of Maug and Pagan in the northern portion of the archipelago.

As the population of Guadalupe fur seals (Arctocephalus townsendi or A. philippii townsendi) continues to recover, this species, which is listed as threatened in the U.S. and endangered in México, is increasingly common in their historical range extending from central México to Washington State. Relatively little is known about this species compared with other pinnipeds that occur in the California Current System. Accurate and current population estimates are lacking because censuses at the only rookery have been sparse and sporadic, and there is a paucity of data on at-sea movements because few individuals have been tracked using telemetry instruments. Therefore, the goal of this multiyear study was to better understand Guadalupe fur seal abundance, behavior, distribution, and habitat use, and to determine the degree to which this recovering population uses U.S. Navy training and testing ranges in the Northeast Pacific.

Guadalupe fur seals are listed as threatened under the U.S. Endangered Species Act and endangered under Mexican law. However, prior to the first year of this study in 2018, the last full census for this species was in 2010, making it difficult to develop current and accurate population estimates and trends. To determine the degree to which this recovering population uses U.S. Navy training and testing ranges in the North Pacific, updated population information for Guadalupe fur seals is needed in addition to tracking at-sea movement patterns using satellite transmitters. Similar to 2018, during the 2019 summer breeding season, direct counts of Guadalupe fur seals were conducted at Guadalupe Island and San Benito Archipelago, México.

This report presents detailed results from the tagging, biopsy sampling, and photo-identification efforts conducted off the coast of northern Washington and central Oregon in summer 2018, as well as results from previous OSU studies of humpback whales in Oregon in 2016 and 2017. Whale use of Navy training and testing areas as well as their use of NMFS-identified Biologically Important Areas (BIAs) is examined and assignment to various DPSs (based on tracking, genetic, and photographic information) is discussed. Comparisons are made to tracking results from humpback whales tagged by OSU in California in 2004, 2005, and 2017 (presented in Mate et al. 2018a). For the 2018 data, this report also presents detailed dive behavior analyses and ecological relationships between whale locations and oceanographic conditions.

This report presents detailed results from the tagging, biopsy sampling, and photo-identification (photo-ID) efforts conducted in the Hawaiian Islands in 2019, as well as results from previous OSU studies of humpback whales in the Hawaiian Islands from 1995 to 2018. Whale use of Navy training and testing areas as well as their use of NMFS-identified Biologically Important Areas (BIAs) in the Hawaiian Islands and Alaska is also examined.

This report presents results from field efforts conducted off the coast of northern Washington (NWA) in summer and fall 2019, as well as results from previous OSU studies of humpback whales in southern and central California (SCCA), northern California and Oregon (NCA/OR), and NWA from 2004 to 2018.

Passive acoustic monitoring was conducted in the Navy’s Southern California Range Complex from July 2018 to May 2019 to detect marine mammal and anthropogenic sounds. High-frequency Acoustic Recording Packages (HARPs) recorded sounds between 10 Hz and 100 kHz at three locations: two west of San Clemente Island (1,300 m depth, site E and 1,000 m depth, site H) and one southwest of San Clemente Island (1,250 m depth, site N).