US Navy

Marine Species Monitoring

Mid-Atlantic Nearshore & Mid-shelf Baleen Whale Monitoring

Introduction & Objectives

Researchers from HDR and the U.S. Navy have been to conducting a variety of monitoring activities in the Virginia Capes Operating Area (VACAPES OPAREA) within the Atlantic Fleet Training and Testing (AFTT) region since 2012, including vessel-based line transect surveys, behavioral focal follows, photo-identification (photo-ID), biopsy sampling, and satellite-linked telemetry tracking with long-term objectives of documenting marine mammal seasonal occurrence, habitat use, and baseline behavioral ecology in areas with relatively high levels of military and commercial shipping activity. Early work in the nearshore waters focused on bottlenose dolphins (Tursiops Truncatus), and later humpback whales (Megaptera novaeangliae), although other species including endangered fin (Balaenoptera physalus) and North Atlantic right whales (NARW) (Eubalaena glacialis) are known to frequent the region as well.

The Mid-Atlantic Humpback Whale Monitoring Project began in 2015 and provides critical insight on how protected humpbacks utilize waters along the coast of southeastern Virginia and near the entrance to Chesapeake Bay. Results show extended periods of residency over weeks to months, with some whales frequenting the dredged shipping channels used by large vessels (Aschettino et al., 2020). Although this work has been largely focused on humpbacks, relatively little information exists on how other species of baleen whales, including endangered fin (Balaenoptera physalus) and North Atlantic right whales (NARW) (Eubalaena glacialis), utilize the central waters of the VACAPES OPAREA.

Passive acoustic monitoring results from autonomous gliders and Marine Autonomous Recording Units (MARU) confirm that humpback, fin, sei, minke, and NARW regularly utilize the continental shelf waters off the coasts of Virginia and North Carolina (Baumgartner 2019, Salisbury et al. 2018, Stanistreet et al. 2016). Acoustic detections are supported by visual sighting data collected by the Atlantic Marine Assessment Program for Protected Species (AMAPPS), as well as a variety of previous Navy-supported aerial and vessel surveys (Mallette et al. 2018).

Fin whales, considered a strategic stock given their endangered status, appear to show a consistent pattern of occurrence near or over the continental shelf break throughout VACAPES (Hayes et al. 2022, Mallette et al. 2018). Led by researchers from HDR Inc., satellite-monitored tags deployed on fin between 2016 and 2021 within VACAPES show both limited and extensive movements over all areas of the continental shelf (Engelhaupt et al. 2017, Engelhaupt et al. 2018, Engelhaupt et al. 2019, Aschettino et al. 2018, Aschettino et al. 2021, Aschettino et al. 2022). Confirmed sightings of critically endangered NARW off Virginia have increased as survey coverage during the Mid-Atlantic Humpback Whale Project has extend further from and movements of satellite tagged NARWs show extensive use of the mid-shelf region to both the north and south of the primary study area (Aschettino et al. 2022, Engelhaupt et al. 2022b). Although sightings of blue whales (Balaenoptera musculus) off Virginia are infrequent, they have now been documented during surveys in 2018 (Engelhaupt et al. 2019), 2019 (Cotter 2019), 2021 (Engelhaupt 2022a), and 2022, and location data from two satellite tagged blue whales showed at least some movements through the shallow continental shelf waters (Lesage et al. 2017; Engelhaupt et al. 2022a).

Building upon the long-term data collection established through ongoing monitoring of humpback whales, this project establishes an expansion of the existing study area to encompass mid-shelf waters out to approximately 40 NM from shore where baleen whale species variability increases. The goals of this study are to assist the U.S. Navy and regulatory agencies by addressing the following questions:

What is the baseline ecology and behavior of baleen whales (including critically endangered NARWs, fin whales, humpback whales, sei whales, minke whales, and blue whales) within the study area?
Do individual whales exhibit site-fidelity within specific regions of the U.S. Navy OPAREAs over periods of weeks, months, years?
What is the seasonal extent of baleen whale movements within and around U.S. Navy OPAREAs?
Do baleen whales spend significant time within or primarily move through areas of U.S. Navy live-fire or ASW training events?
Are baleen whale movement patterns affected by U.S. Navy training exercises?
Are baleen whales likely exposed to significant sound levels produced by vessel traffic and/or military training exercises using active sonar?

Technical Approach

The primary study area encompasses the nearshore and mid-shelf waters of the VACAPES OPAREA along the southern Virginia and northern North Carolina coasts including within and around the mouth of the Chesapeake Bay. The operating area for each survey is chosen depending on weather and marine conditions, reports of whales in the area, and coordination with aerial surveys.

This project relies on non-systematic visual surveys conducted from small to medium-sized vessels utilizing a variety of techniques including photo-identification, small unmanned aerial systems (sUAS), biopsy sampling, and tagging using medium-resolution satellite tags and high-resolution suction cup tags. Nearshore work with humpback whales will be typically limited to continuing long-term photo-ID monitoring and assessment of body condition and overall health. Tag deployments will primarily be conducted in the mid-shelf region on a variety of baleen whale species opportunistically, although NARW are a high priority. During each encounter, efforts are made to collect photographs of the dorsal fins, tail flukes, and callosities for identification. Biopsy samples may also be collected for sex determination and genetic analysis.

Satellite or suction-cup tags may be deployed depending on the species and potentially individual identification, with a very specific protocol for tagging right whales. Medium-resolution Wildlife Computers Smart Position and Temperature (SPOT6) Argos-linked satellite tags as well as SPLASH10 and SPLASH10F variations that record diving behavior and integrate Fastloc© GPS (Wildtrack Telemetry Systems Limited) will be utilized in the Low Impact Minimally Percutaneous Electronic Transmitter (LIMPET) configuration. These small tags measure only two inches in length and height and less than an inch wide. On most baleen whales, preferred location is on or near the dorsal hump or fin. For right whales the tags are attached approximately mid-line in the dorsal region in as close a proximity as possible to the shoulder blades. This placement allows frequent transmissions to the Argos satellites when the animals surface, providing data on location and diving behavior. The tags are designed to eventually fall off the animal after a period of weeks to months.

High-resolution suction cup tags include version 3 DTAGs (Johnson and Tyack 2003) and CATS tags, both deployed using a hand-held carbon fiber pole. Both types of tags are equipped with hydrophones and pressure sensors as well as a three-axis accelerometer and magnetometer. The CATS tag also collects HD video which will be used to examine foraging, surfacing, and social behavior in detail. Suction cup tags are programmed to release after a specified duration and can be located and recovered with a radio VHF receiver following release.

Primary objectives during field work include:

1. Collect baseline occurrence data (location, group size, behavior) of baleen whales

2. Obtain identification photographs and drone video footage for inclusion in regional and local catalogs, as well as morphometric measurements and health assessments

3. Collect biopsy samples of baleen whales for sex determination, mitochondrial control region sequencing, and microsatellite genotyping of tissue samples, and stable isotope analysis to assess foraging related to prey consumption

4. Deploy satellite and suction-cup tags to document seasonal movement patterns in the nearshore and mid-shelf waters off Virginia Beach, specifically whether the whales spend significant time in areas of high shipping traffic and/or areas of U.S. Navy training exercises

Progress & Results

This project transitioned from the Mid-Atlantic Humpback Whale Monitoring Project in November 2020. From November 2020 through March 2024, researchers from HDR and the U.S. Navy have conducted 207 seasonal nearshore and mid-shelf surveys, totaling 1,545 hours of effort covering 25,943km of trackline. During these surveys, there have been 612 baleen whale sightings of 849 individuals.

The program's humpback whale catalog consists of 298 individuals seen in the area since 2012. Humpback photo-IDs are incorporated into the Mid-Atlantic Humpback Whale Catalog and also shared with other regional catalogs, including Happy Whale. Although matching for these images is ongoing, matches to known animals from the Gulf of Maine, Newfoundland, and St. Pierre and Miquelon have been made. Photographs of NARWs are also submitted to the New England Aquarium for incorporation into the North Atlantic Right Whale Catalog (http://rwcatalog.neaq.org/). The 2022/23 and 2023/24 field seasons in particular yielded several important sightings of North Atlantic right whales.

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