Two ecological acoustic recorders (EARs) were deployed on July 17, 2010, one at a depth of 800 meters (m) off the northwest coast (21° 59.613' N, 160° 12.167' W), and the other at a depth of 16 m off the southeast coast of Ni'ihau (21° 47.306' N, 160° 11.964' W). These two sites were selected by personnel from the Naval Facilities Engineering Command, Pacific to provide acoustic data during the 2010 Rim of the Pacific (RIMPAC) exercise in the Hawaii Range Complex.

Ecological acoustic recorders (EARs) have been deployed at several locations in Hawaii and in other western Pacific locations to study the foraging behavior of deep-diving odontocetes. EARs have been deployed at depths greater than 400 m at five locations around the island of Kauai, one at Ni’ihau, two around the island of Okinawa, and four in the Marianas (two close to island of Guam, one close to the island of Saipan and another close to the island of Tinian).

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.

The purpose of this report is to summarize information obtained through the remote deployment of Low-Impact Minimally-Percutaneous External-electronics Transmitter (LIMPET) satellite tags on odontocete cetaceans off Cape Hatteras, North Carolina, in 2014. This study was undertaken to provide information on spatial use and diving behavior of a number of species of odontocetes, with particular emphasis on Cuvier’s beaked whales (Ziphius cavirostris) and short-finned pilot whales (Globicephala macrorhynchus).

The present work is intended to complement ongoing research by Duke University off Cape Hatteras (hereinafter referred to as the Duke program) by providing information on the movement and diving behavior of these species over the medium term (weeks to months). The Duke program is focusing on shorter-term dive behavior (i.e., hours to days) using Digital Acoustic Tags and longer-term movements (i.e., months to years) using photo-identification (photo-ID) techniques

. This report summarizes information obtained through additional field efforts undertaken in 2016, while incorporating results from the first two years of effort. The present work is intended to complement ongoing research by Duke University off Cape Hatteras (hereinafter referred to as the Duke program) by providing information on the movement and diving behavior of these species over the medium term (weeks to months)

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)

Acoustic point-transect distance-sampling surveys have recently been used to estimate the density of beaked whales. Typically, the fraction of short time “snapshots” with detected beaked whales is used in this calculation. Beaked whale echolocation pulses are only intermittently available, which may affect the best choice of snapshot length. The effect of snapshot length on density estimation for Cuvier's beaked whale (Ziphius cavirostris) is investigated by sub-setting continuous recordings from drifting hydrophones deployed off southern and central California. Snapshot lengths from 20 s to 20 min are superimposed on the time series of detected beaked whale echolocation pulses, and the components of the density estimation equation are estimated for each snapshot length. The fraction of snapshots with detections, the effective area surveyed, and the snapshot detection probability all increase with snapshot length. Due to compensatory changes in these three components, density estimates show very little dependence on snapshot length. Within the range we examined, 1–2 min snapshots are recommended to avoid the potential bias caused by animal movement during the snapshot period and to maximize the sample size for estimating the effective area surveyed.

Passive acoustic monitoring was conducted in the Navy’s Southern California Range Complex from January 2013 to June 2017 to detect marine mammal sounds. High-frequency Acoustic Recording Packages (HARPs) recorded sounds between 10 Hz and 100 kHz at four locations: west of San Clemente Island (1,000 m depth, site H), south of San Clemente Island (1200 m depth, site N), northwest of San Clemente Island (900 m depth, site M) and west of La Jolla, California (500 m depth, site P).

We present progress on the development of methods to investigate the potential impacts of sonar and other anthropogenic activities on calling animals. The basis for this effort is previously collected PAM data from four sites in the years 2006 to 2015. Recording effort at these sites varied between 674 and 2,284 days per site, resulting in 19 years of cumulative acoustic recording during 79 instrument deployments and 227 TB of acoustic recordings. As part of the work in this progress report, automated routines have been established and/or modified to detect and classify acoustic signals of blue whales (Balaenoptera musculus) and Cuvier’s beaked whales (Ziphius caviostris) as well as Mid-Frequency Active (MFA) sonar pings and explosions.

Passive acoustic monitoring (PAM) provides extensive datasets to examine the behavioral response of cetaceans to anthropogenic sound. Using broadband passive acoustic monitoring, the full range of cetacean sounds and the sounds of naval and other anthropogenic sources are recorded. We have been collecting high-frequency PAM data in the Southern California (SOCAL) region since 2006. Within this dataset are many instances of anthropogenic sound as well as cetacean presence at the locations of naval training.

Mesoscale oceanographic features are a major force in structuring the marine environment through processes such as eddy-induced upwelling, and as such effect distribution and aggregation patterns of all organisms along the food chain. It has been shown that top pelagic predators such as cetaceans react to these environmental changes in different ways. We present analysis of frequency-modulated (FM) echolocation pulses of Cuvier’s beaked whale (Ziphius cavirostris), Blainville’s beaked whale (Mesoplodon densirostis), and an unknown beaked whale species producing FM pulse type “BWC,” possibly ginkgo-toothed beaked whale (M. ginkgodens), at five locations in the central Pacific. The recordings were collected at Pearl and Hermes Reef (Northwestern Hawaiian Islands), Kona (Main Hawaiian Islands), Wake Atoll, Tinian, and Saipan (Northern Mariana Islands) between 2008 and 2015, ranging from 4 to 8 years per site. All three beaked whale species were present at all sites in different proportions throughout the recording periods, with a strong nocturnal pattern only for the “BWC” pulse type, yet without seasonal pattern. We examine the varying presence in the context of remotely sensed oceanographic data, including sea surface height deviation, temperature, and salinity, as well as chlorophyll a and derived primary productivity.

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 Hawaiian Islands Cetacean and Ecosystem Assessment Survey (HICEAS) is a recurring ship-based, line-transect survey designed to estimate cetacean abundance in the entirety of the Hawaiian EEZ.

We tested this prediction by evaluating the diving behavior of animals within social groups off Cape Hatteras, North Carolina, considering diving synchrony a proxy for group membership.

We analyze trade-offs in the longevity, resolution, and continuity of data records from non-recoverable satellite-linked tags on deep-diving Ziphius cavirostris in the context of a behavioral response study of acute noise exposure.

The first cetacean circovirus, beaked whale circovirus (BWCV), was recently reported in a Longman’s beaked whale (Indopacetus pacificus) stranded in Hawai‘i and represents an emergent disease with unknown population impacts. In other species, circovirus infection may cause mortality or opportunistic co-infection by other pathogens. We report on a targeted surveillance of stranded cetaceans in the Pacific basin, including archived beaked whale species, strandings where pathological findings suggested disease presence, mass stranded animals, and additional individuals to represent a broad range of Hawaiian cetacean species. Archived tissues primarily from the brain, kidney, liver, lung, spleen, and lymph nodes of individuals stranded between 2000 and 2020 (n=30) were tested by PCR for the presence of BWCV.

Beaked whales are among the most poorly understood marine mammals. They are deep-diving odontocetes, spending most of their time submerged with infrequent, short surface intervals. Due to this behavior, they are difficult to study using visual observation methods alone . However, recent advancements in passive acoustic detection and survey techniques have shown to provide viable methods for stu dying beaked whales (Yack et al. 2013). In the Gulf of Alaska (GOA), there is little known abo ut beaked whale abundance and distribution.

A combination of machine learning and expert analyst review was used to detect odontocete echolocation clicks, identify dominant click types, and classify clicks in 32 years of acoustic data collected at 11 autonomous monitoring sites in the western North Atlantic between 2016 and 2019. Previously-described click types for eight known odontocete species or genera were identified in this data set: Blainville’s beaked whales (Mesoplodon densirostris), Cuvier’s beaked whales (Ziphius cavirostris), Gervais’ beaked whales (Mesoplodon europaeus), Sowerby’s beaked whales (Mesoplodon bidens), and True’s beaked whales (Mesoplodon mirus), Kogia spp., Risso’s dolphin (Grampus griseus), and sperm whales (Physeter macrocephalus)

This study supports the notion that scarring density is indicative of sex for this species, improves the predictive capacity of this metric inter-regionally, and provides a reliable method to estimate the sex of whales in a typical photo-ID catalog, thus supporting vital rate assessments for this data-deficient species.

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.

Bayesian mark-recapture estimates of survival, abundance, and trend are reported for Cuvier's beaked whales (Ziphius cavirostris) using a Navy training range off southern California. The deep-diving beaked whale family is exceptionally vulnerable to mid-frequency active sonar (MFAS), which has been implicated in mass strandings and altered foraging behavior. Extremely low sighting probabilities impede studies of population-level impacts of MFAS on beaked whales. The San Nicolas Basin hosts a Navy training range subject to frequent MFAS use and attracts high densities of Z. cavirostris. An 11-year (2007–2018) photo-identification program leveraged automated acoustic detection and location capabilities on the range's 1,800-km2 hydrophone array to enhance capture probability.

Passive acoustic monitoring was conducted to detect the presence of marine mammal and anthropogenic sounds in the Navy’s Northwest Training Range Complex (NWTRC) from September 14, 2012 until June 30, 2013. High-frequency Acoustic Recording Packages (HARPs) recorded sounds between 10 Hz and 100 kHz at the shelf slope near Quinault Canyon. Data analysis methods consisted of detection of sounds by analyst scans of long-term spectral averages (LTSAs) and spectrograms, and by automated computer algorithms when possible. The data were divided into three frequency bands for analysis of marine mammal vocalizations and anthropogenic sounds.

Passive acoustic monitoring was conducted in the Gulf of Alaska Temporary Maritime Activities Area (GATMAA) from June 2013 to May 2014 to detect marine mammal and anthropogenic sounds. High-frequency Acoustic Recording Packages (HARPs) recorded sounds between 10 Hz and 100 kHz at five locations: a shelf site offshore Kenai Peninsula (200 m depth, site CA), a continental slope site in deep water (850 m depth, site CB), a slope site offshore Kodiak Island (230 m depth, site KO), a deep offshore site at Pratt Seamount (1000 m depth, site PT), and a deep offshore site at Quinn Seamount (930 m depth, site QN).

Passive acoustic monitoring was conducted in the Navy’s Southern California Range Complex from December 2012 to January 2014 to detect marine mammal and anthropogenic sounds. High-frequency Acoustic Recording Packages (HARPs) recorded sounds between 10 Hz and 100 kHz at three locations: near Santa Barbara Island (880 m), west of San Clemente Island (1000 m), and southwest of San Clemente Island (1300 m). Six baleen whale species were recorded: blue whales, Bryde’s whales, fin whales, gray whales, humpback whales, and minke whales.

Passive acoustic monitoring was conducted in the Navy’s Southern California Range Complex from January to July 2014 to detect marine mammal and anthropogenic sounds. High-frequency Acoustic Recording Packages (HARPs) recorded sounds between 10 Hz and 100 kHz at three locations: west of San Clemente Island (1,000 m depth, site H), southwest of San Clemente Island (1,200 m depth, site N), and west of La Jolla, California (550 m depth, site P). Sites H and N are located offshore, whereas site P is located nearer to the coast.

Passive acoustic monitoring was conducted within the Navy’s Cherry Point OPAREA during August – December 2011 and July – October 2012 for a total of 105 and 81 days respectively. This site is located approximately 100 miles from the North Carolina coastline on the shelf break. The 2011 deployment was at a water depth of 952 m and the 2012 deployment was at a water depth of 914 m. Acoustic data collected at this site provide information on the presence of marine mammals and anthropogenic sound sources. High-frequency Acoustic Recording Packages (HARPs) recorded sounds between 10 Hz and 100 kHz with recording cycles of 5 minutes every 10 minutes. The data were divided into three frequency bands and data were analyzed by scans of long-term spectral averages and spectrograms. Four baleen whale species were recorded: blue, fin, minke, and sei whales. The detections of their calls were made between late August and early December 2011. Blue whale calls were the only baleen whale call type detected in the 2012 deployment. No Bryde’s, humpback, or North Atlantic right whale calls were detected in either deployment. Several different toothed whale species were recorded: Blainville’s, Cuvier’s, and Gervais’ beaked whales, killer whales, pygmy or dwarf sperm whales (Kogia spp.), Risso’s dolphins, sperm whales, and unidentified odontocetes. All species except killer whales were recorded in 2011 and 2012. Killer whales were detected only in 2011. Ship noise was the most common anthropogenic sound in both deployments. MFA was noted during both deployments. A total of 391 pings were detected in 2011 with a maximum peak-to-peak received level of 156 dB re 1 μPa. In 2012, a total of 492 pings were detected with a maximum peak-to-peak received level of 167 dB re 1 μPa. Few echosounder pings over a variety of frequencies (4-80 kHz) were detected during both deployments. Explosions were detected in both deployments, though they were more prevalent in 2011 than 2012. High noise levels, possibly caused by instrument strumming and fluid flow at the sensor, occurred intermittently in both deployments and likely decreased the detection range for low-frequency sounds. This strumming was most prevalent in 2012.

Navy Research Funded Year Three Project Reports

This document contains amplifying technical data and information for the United States Department of the Navy’s Southern California Range Complex Comprehensive Monitoring Report.

Whales and dolphins use sound for different functions including echolocation and social communication, and thus changes in sound production patterns are a likely component of any behavioral response to anthropogenic sounds such as military mid-frequency sonar (MFA). To simultaneously log whale and dolphin movements, sound production and reception, and anthropogenic sound exposure levels, we used Dtags (Woods Hole Oceanographic Institution) and bioacoustic probes (Greeneridge Sciences). Tags were deployed on wild, free-ranging cetaceans in Southern California waters. Tagged animals were then exposed to simulated MFA or, as a control, pseudo-random noise (PRN). In total, the August-September 2010 SoCal10 behavioral response study included 28 playbacks: 19 to blue whales (11 MFA, 8 PRN), 5 to fin whales (3 MFA, 2 PRN), 2 to a single sperm whale (1 MFA, 1 PRN), 1 to a Risso’s dolphin (MFA), and 1 to a Cuvier’s beaked whale (MFA). For this analysis we focus first on baleen whale call production and reception rates (particularly blue whale D calls and variable calls) in relation to sound exposure level, dive behavior, and lunge feeding rates. We then examine echolocation-based foraging behavior and social call production by the toothed whales as a function of sound exposure level. This rich dataset, including multiple cetacean species of conservation concern, provides insight into the wide potential range of responses to sound, and the dependence of those responses on ecological, social and behavioral context. Investigations like SoCal10 can help guide inferences for related topics, such as assessment of population effects of anthropogenic noise.

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.

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.

Cuvier’s beaked whale abundance estimates have been obtained at the U.S. Navy’s Southern California Anti-Submarine Warfare Range (SOAR) for the period from August 2010 through November 2018. Data for December 2018 through January 2019 are currently being processed. The data were corrected for effort and spatial variation by applying correction factors as in DiMarzio et al (2017). Since 2010, the Cuvier’s beaked whale abundance at SOAR appears to be stable or slightly increasing.

In 2016, corrected Cuvier’s beaked whale (Ziphius cavirostris, Zc) abundance estimates at SOAR were completed for 2010 -2014. The estimates showed no decline in abundance over this 5-year period on the instrumented Southern California Anti-Submarine Warfare Range (SOAR). In 2017, these estimates were updated with data from 2015 through September of 2017 to provide a yearly estimate from 2010 to 2017. Periods of node or in-water hardware outages in past estimates and new data were isolated. Correction factors for these periods were calculated, and revised abundance estimates were produced. As before, the data do not show a decline in abundance on SOAR over the last eight years.

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.

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.

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 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 United States (U.S.) Navy routinely conducts training and testing activities in the Virginia Capes (VACAPES) Operating Area (OPAREA) off the mid-Atlantic and Southeast U.S. The region encompassing the deeper waters of the continental shelf, shelf break, and continental slope has been recognized as an important habitat for multiple species of cetaceans. Kenney and Winn (1986) showed that the shelf edge from Cape Hatteras to Georges Bank was the second most intensively used cetacean habitat off the northeastern U.S. based on 3 years of surveys conducted by the Cetacean and Turtle Assessment Program (CETAP 1982). This progress report includes all offshore monitoring activities conducted in 2021. The goals of this effort focus on addressing fundamental information gaps related to marine mammal occurrence, exposure, and response as identified by the U.S. Navy’s Integrated Comprehensive Monitoring Program (DoN 2010) and recommendations provided by a Scientific Advisory Group review (DoN 2011).

Taking into consideration the multiple intermediate scientific objectives in the U.S. Navy’s Strategic Planning Process (DoN 2013b), the goals of this study are to assist the U.S. Navy and regulatory agencies with environmental planning and compliance by addressing the following questions: • Which cetacean species occur over the outer continental shelf to the east of NSN, and how does occurrence fluctuate seasonally? • What are the baseline behaviors and ecological relationships of offshore cetaceans within the study area? • Do individual cetaceans exhibit site fidelity within specific regions of the study area over periods of weeks, months, or years? • What is the seasonal extent of cetacean movements within and around U.S. Navy VACAPES training range boxes? • Do cetaceans spend significant time within or primarily move through areas of U.S. Navy live-fire or Anti-Submarine Warfare training events?

Taking into consideration the multiple intermediate scientific objectives in the U.S. Navy’s Strategic Planning Process (DoN 2013b), the goals of this study are to assist the U.S. Navy and regulatory agencies with environmental planning and compliance by addressing the following questions:  Which cetacean species occur over the outer continental shelf to the east of NSN, and how does occurrence fluctuate seasonally?  What are the baseline behaviors and ecological relationships of offshore cetaceans within the study area?  Do individual cetaceans exhibit site fidelity within specific regions of the study area over periods of weeks, months, or years?  What is the seasonal extent of cetacean movements within and around U.S. Navy VACAPES training range boxes?  Do cetaceans spend significant time within or primarily

Taking into consideration the multiple intermediate scientific objectives in the U.S. Navy’s Strategic Planning Process (DoN 2013b), the goals of this study are to assist the U.S. Navy and regulatory agencies with environmental planning and compliance by addressing the following questions:  Which cetacean species occur over the outer continental shelf to the east of NSN, and how does occurrence fluctuate seasonally?  What are the baseline behaviors and ecological relationships of offshore cetaceans within the study area?  Do individual cetaceans exhibit site fidelity within specific regions of the study area over periods of weeks, months, or years?  What is the seasonal extent of cetacean movements within and around U.S. Navy VACAPES training range boxes?  Do cetaceans spend significant time within or primarily

This report summarizes data collected during small-vessel surveys for cetaceans in the Southern California Bight (SCB), with a focus on the Southern California Offshore Range Complex (SCORE), from June 2010–January 2014. Detailed annual progress reports were prepared after each survey year through 2013 and are available online through the Naval Postgraduate School. This final report emphasizes analyses that combine data across study years, particularly with respect to two focal species: Cuvier’s beaked (Ziphius cavirostris, Zc) and fin (Balaenoptera physalus, Bp) whales.

Results from the second year of a three-year project investigating the distribution, demographics, and behavior of cetaceans in the US Navy’s Southern California operational area are summarized. Eighteen small vessel surveys for cetaceans, which included species verification tests in conjunction with M3R (Marine Mammal Monitoring on Navy Undersea Ranges) acoustic monitoring at the Southern California Anti-submarine Warfare Range (SOAR), as well as photo-identification, satellite tagging, and biopsy sampling of species of interest, were conducted in July 2011 and January and March 2012. 112 groups of 14 cetacean species were encountered. Twenty-one satellite tags, some depth reporting, were deployed on four species, with an emphasis on Cuvier’s beaked and fin whales. Among other findings, preliminary results of photo-identification studies combined with results from satellite tag data suggest that both Cuvier’s beaked whales and fin whales may have population sub-units with higher than expected residency to the Southern California Bight. Beaked whales particularly show this higher than expected residency to SOAR.

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. 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

This report describes results from 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 program began in 2007, with baseline aerial and vessel surveys and a passive acoustic monitoring program in Onslow Bay, North Carolina, and has since expanded to include study areas off Jacksonville, Florida and Cape Hatteras, North Carolina.

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. The program began in 2007, with baseline aerial and vessel surveys and a passive acoustic monitoring program in Onslow Bay, North Carolina, and has since expanded to include study areas off Jacksonville, Florida, and Cape Hatteras, North Carolina. Off Cape Hatteras, four years of surveys have provided information on the complex patterns of distribution and diversity of the marine mammals and sea turtles in this highly productive area. The current report builds on this past body of work and describes activities conducted during both the Deep Divers and Satellite Tagging projects conducted off Cape Hatteras between January and December 2014. This constitutes the second year of the Deep Divers project, which focuses on the distribution and ecology of several deep-diving odontocete species, including: beaked whale (Cuvier’s beaked whale: Ziphius cavirostris and Mesoplodon spp.); short-finned pilot whale (Globicephala macrorhynchus); and sperm whale (Physeter macrocephalus). To achieve a more robust picture of the medium-term movement patterns of these and other odontocete cetaceans in the Cape Hatteras survey area, we began a satellite tagging project during the reporting period. Satellite tagging effort and associated sightings are presented here; preliminary analyses of movement data are available in a separate report generated by the Cascadia Research Collective (see Baird et al. 2015). All survey effort in the Cape Hatteras study site this year was dedicated to Deep Divers and Satellite Tagging projects, so we also report ongoing photographic identification work for this area in this report.

Short-finned pilot whales (Globicephala macrorhynchus) and Cuvier’s beaked whales (Ziphius cavirostris) are deep-diving odontocetes with broad distributions, and are of conservation concern given their history of increased injury and mortality resulting from direct interactions with fisheries and mass strandings resulting from mid-frequency active sonar. In the western North Atlantic, basic information on the spatiotemporal distribution, movement patterns, habitat preferences, home ranges, and residency of these highly mobile species are still unknown.

Here we describe the spatial ecology of 20 Cuvier’s beaked whales equipped with satellite-linked tags off Cape Hatteras, North Carolina, USA, between 2014 and 2017.

The goal of our project “Southern California Beaked Whale Occurrence from Towed Array Surveys” is to support the US Navy environmental compliance requirements for monitoring marine mammals. This research effort is performed by the University of California San Diego (UCSD) Scripps Institution of Oceanography (SIO) in La Jolla, CA as part of a larger effort. Data collected by a shipboard towed array acoustic survey for marine mammals is being analyzed. These data will provide for spatial assessment of Southern California beaked whale occurrence from towed array surveys.

To monitor for the presence of marine mammals, a High-frequency Acoustic Recording Package (HARP) recorded within the Navy’s Virginia Capes Range Complex, offshore from Cape Hatteras (HAT), between April 2015 and January 2016. The HAT site was located approximately 75 nm offshore in about 1000 m of water.

The overall objective of the ICMP is to assimilate relevant data collected across U.S. Navy range complexes in order to answer questions pertaining to the impact of MFAS and explosives on marine mammals and sea turtles.

The first phase to integrate the historical sum of these U.S. Navy-sponsored visual survey efforts for marine species monitoring in the HRC was prepared by Uyeyama (2011). This report represents the second phase of that effort and presents an overview of monitoring survey effort to date in the HRC. Available data from visual surveys performed by both contractor-led efforts and U.S. Navy in-house surveys was compiled and processed in order to: 1. Create a geographic information system (GIS)-based summation of all survey tracks that can be easily visualized. 2. Construct a geo-referenced database of sightings that can be queried by species, observer platform, Beaufort Sea State (BSS), season, or other sighting/survey variables. 3. Conduct an enhanced analysis of sighting success with respect to survey platform, field protocol, and environmental conditions. 4. Inform and adjust data collection procedures on future surveys as needed to reflect lessons learned from sighting data compilation efforts presented here. 5. Provide information to enhance informed management of marine protected species in the HRC and support the adaptive management process that is part of the ICM

This report presents a geographic information system (GIS)-based overview of the sighting records obtained during marine species monitoring effort (a total of 12 U.S. Pacific Fleet-funded surveys) to date in the MIRC. Also included are incidental marine mammal and sea turtle sightings made since 1965 on non-dedicated surveys in the region.

Beaked whales (family Ziphiidae) consist of at least 21 different species in six genera with relatively little known about many of the species. Research on this family of odontocetes has increased in the last two decades as a result of a mass stranding event of beaked whales in the Bahamas in 2000 in association with a U.S. Navy training event. Results of this research have identified echolocation click characteristics for several species from different areas of the world based upon both tag data and passive acoustic monitoring data

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).

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.

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

To identify possible behavioral responses in dive data collected from satellite-linked time–depth recorders, and to inform the selection and parameters for subsequent individual and population-level response analyses, we propose to use kernel density estimates of conditional distributions for quantitative comparison of pre- and post-exposure behavior.

Understanding unexposed/baseline behavior of marine mammals is required to assess the effects of increasing levels of anthropogenic noise exposure in the marine environment. However, quantifying variation in the baseline behavior of whales is challenging due to the fact that they spend much of their time at depth, and therefore, their diving behavior is not directly observable. Data collection employs tags as measurement devices to record vertical movement. We focus here on satellite tags, which have the advantage of collection over a time window of weeks.

Progress is reported on efforts to estimate the density of Cuvier’s beaked whales (Ziphius cavirostris), using passive acoustic monitoring data collected with Navy support at sites in the Southern California Bight. Two methods for estimating weekly densities of beaked whales are presented, one based on the number of echolocation clicks detected (click counting) and the other based on the presence of clicks during 1-min time bins indicating the presence of animal groups (group counting). The click-based method requires an estimate of mean click production rate, while the group-based method requires the proportion of 1-min bins a group is vocally active. These parameters are obtained from tagging and tracking data collected for Cuvier’s beaked whales in Southern California and other locations.

Passive acoustic monitoring was conducted in the Navy’s Southern California Range Complex during May 2011 – March 2012 to detect the presence of marine mammal and anthropogenic sounds. Highfrequency Acoustic Recording Packages (HARPs) recorded sounds between 10 Hz and 100 kHz with nearly continuous temporal coverage at a site near Santa Barbara Island (site M) and at a site west of San Clemente Island (site H). Data analysis consisted of detection of sounds of interest by analyst scans of long-term spectral averages and spectrograms, and by automated computer algorithm detection when possible. Representative sounds are presented in this report, as well as details of the computer algorithms used to detect them.

Passive acoustic monitoring was conducted at two sites in the Navy’s Southern California Range Complex during April 2010 – April 2011. These data provide information on the presence of marine mammals and anthropogenic sound sources. High‐frequency acoustic recording packages documented sounds between 10 Hz and 100 kHz with nearly continuous temporal coverage at a site near Santa Barbara Island (site M) and a site south of San Clemente Island (site N). For this reporting period, 8,099 hours of acoustic recordings were obtained from site M and 7,779 hours of recordings from site N. Data analysis methods consisted of analyst scans of long‐term spectral averages and spectrograms. The data were divided into three frequency bands and each band was analyzed for the sounds of marine mammal species or anthropogenic sources. Representative sounds are presented.

This report summarizes data analysis for deployment of a High Frequency Acoustic Recording Package (HARP) in the southern California (SOCAL) offshore region. The HARP records broadband (10 Hz – 100 kHz) acoustic data, including both marine animal and anthropogenic sound. This report summarizes initial analysis to detect the presence of marine mammals by species as well as the occurrence of naval sonar and other anthropogenic sound events.

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.

The PIFSC CRP has conducted research on cetaceans in the Mariana Archipelago since 2010. A cooperative effort with funding from U.S. Navy Pacific Fleet and PIFSC has included summer and winter small-boat surveys off the southernmost islands (Saipan, Tinian, Aguijan, Rota, and Guam), development of photo-ID catalogs, analysis of collected tissue samples and satellite telemetry tag data, and shipboard visual and PAM surveys in portions of the EEZ in 2010 and 2015. PIFSC has maintained long-term PAM on moored recorders off Saipan and Tinian (since 2010) and off Pagan (since 2015) as part of the Pacific Islands Passive Acoustic Network (PIPAN). The goal of these efforts is to collect the data necessary to conduct population assessments for cetaceans within the Mariana Archipelago, including the determination of their occurrence, population structure and abundance, movements, distribution, and habitat use.

The Pacific Islands Fisheries Science Center’s (PIFSC) Cetacean Research Program (CRP) has been conducting visual surveys and long-term acoustic monitoring for cetaceans in the waters surrounding Guam and the Commonwealth of the Northern Mariana Islands (CNMI) as part of an ongoing effort to develop a record of cetacean occurrence in the region. Visual surveys have been conducted aboard small boats (7.6-12.2 m) since 2010 off the southernmost islands of the Mariana Archipelago (Guam, Rota, Saipan, Tinian, and Aguijan). These surveys include the collection of photographs for individual identification, tissue samples for genetic analysis of population structure, and the deployment of satellite tags for assessment of individual movements throughout the broader region.

The Pacific Islands Fisheries Science Center’s (PIFSC) Cetacean Research Program (CRP) has been conducting visual surveys for cetaceans in the waters surrounding Guam and the Commonwealth of the Northern Mariana Islands (CNMI) and collecting long-term passive acoustic monitoring data at two sites in CNMI as part of an ongoing effort to develop a record of cetacean occurrence in the region. Visual surveys, conducted aboard small boats (7.6 – 12.2 m), have been ongoing since 2010 off the southern Mariana Islands of Guam, Rota, Saipan, Tinian, and Aguijan. T

Anthropogenic activities can lead to changes in animal behavior. Predicting population consequences of these behavioral changes requires integrating short-term individual responses into models that forecast population dynamics across multiple generations. This is especially challenging for long-lived animals, because of the different time scales involved. Beaked whales are a group of deep-diving odontocete whales that respond behaviorally when exposed to military mid-frequency active sonar (MFAS), but the effect of these nonlethal responses on beaked whale populations is unknown. Population consequences of aggregate exposure to MFAS was assessed for two beaked whale populations that are regularly present on U.S. Navy training ranges where MFAS is frequently used. Our approach integrates a wide range of data sources, including telemetry data, information on spatial variation in habitat quality, passive acoustic data on the temporal pattern of sonar use and its relationship to beaked whale foraging activity, into an individual-based model with a dynamic bioenergetic module that governs individual life history.

A High-frequency Acoustic Recording Package (HARP; Wiggins and Hildebrand 2007) was deployed between October 2012 and August 2013 in Onslow Bay at Site E in 853 m. This HARP sampled at 200 kHz for 5 minutes of every 10 minutes and recorded for 250 days between 24 October 2012 and 30 June 2013. Long-Term Spectral Averages (LTSAs) were created for three frequency bands (10 Hz – 1000 Hz, 500 Hz – 5000 Hz, and 1 kHz – 100 kHz) and scanned for marine mammal vocalizations. Calls of blue whales, fin whales, minke whales, possible sei whales, Blainville’s beaked whales, Cuvier’s beaked whales, Gervais’ beaked whales, Kogia spp., Risso’s dolphins, sperm whales, and unidentified odontocetes and mysticetes were detected in the data.

A High-frequency Acoustic Recording Package (HARP; Wiggins and Hildebrand 2007) was deployed between March and October 2012 in the Cape Hatteras survey area at Site A in approximately 950 m. This HARP sampled continuously at 200 kHz and recorded for 28 days between 15 March 2012 and 11 April 2012. Long-Term Spectral Averages (LTSAs) were created for two frequency bands (10 Hz – 1000 Hz and 1 kHz – 100 kHz) and scanned for marine mammal vocalizations. Calls of fin whales, minke whales, beaked whales, Kogia spp., Risso’s dolphins, sperm whales, and unidentified delphinids were detected in the data.

A High-frequency Acoustic Recording Package (HARP; Wiggins and Hildebrand 2007) was deployed between August 2011 and July 2012 in Onslow Bay at Site E in 952 m. This HARP sampled at 200 kHz for 5 minutes of every 10 minutes and recorded for 105 days between 19 August 2011 and 1 December 2011. Long-Term Spectral Averages (LTSAs) were created for three frequency bands (10 Hz – 1000 Hz, 500 Hz – 5000 Hz, and 1 kHz – 100 kHz) and scanned for marine mammal vocalizations. Calls of blue whales, fin whales, minke whales, possible sei whales, an unidentified beaked whale species, Blainville’s beaked whales, Cuvier’s beaked whales, Gervais’ beaked whales, killer whales, Kogia spp., Risso’s dolphins, sperm whales, and unidentified delphinids were detected in the data.

A High-frequency Acoustic Recording Package (HARP; Wiggins and Hildebrand 2007) was deployed between July and October 2012 in Onslow Bay at Site E in 914 m. This HARP sampled at 200 kHz for 5 minutes of every 10 minutes and recorded for 81 days between 14 July 2012 and 2 October 2012. Long-Term Spectral Averages (LTSAs) were created for three frequency bands (10 Hz – 1000 Hz, 500 Hz – 5000 Hz, and 1 kHz – 100 kHz) and scanned for marine mammal vocalizations. Calls of blue whales, Blainville’s beaked whales, Cuvier’s beaked whales, Gervais’ beaked whales, Kogia spp., Risso’s dolphins, sperm whales, and unidentified delphinids were detected in the data.