2024 Sea Scallop Survey Results

Among the highlights of our 2024 Integrated Sea Scallop and HabCam Research Survey are strong numbers of two-year-old scallops observed in both dredge samples and HabCam images. These were found in the southern part of the Great South Channel, the eastern portion of the Nantucket Lightship Area, the northern portion of Closed Area I, and in the Elephant Trunk and Hudson Canyon South areas in the Mid-Atlantic. Sea scallops typically reach harvestable size at about age 4 and older.

This is also the first survey that included three cruises, exclusively used a commercial vessel for dredging, and deployed a Tethys-class long-range autonomous underwater vehicle.

This year, we deployed the HabCam V4 and the new LRAUV, nicknamed “Stella,” from the R/V Hugh R. Sharp, owned and operated by the University of Delaware. Then, we completed a dredge survey aboard a chartered commercial scalloper, F/V Selje. Finally, we deployed both the HabCam V4 and Stella from the NOAA Ship Henry B. Bigelow.

The HabCam IV and Stella vehicles continuously photograph the ocean bottom while they collect other data about conditions in the waters in which they operate. Stella was designed by the Monterey Bay Aquarium Research Institute. It is owned and operated by the Woods Hole Oceanographic Institution, equipped with WHOI-designed stereo imaging camera payloads.

The dredge is a standardized 8-foot-wide New Bedford sea scallop dredge that collects sea scallops and associated bycatch for biological analyses along with some environmental variables.

The Atlantic sea scallop population is surveyed every summer by NOAA Fisheries and partnering research groups, supported through the Sea Scallop Research Set-Aside program. This year those partners are:

• Coonamessett Farm Foundation
• Maine Department of Marine Resources
• University of Massachusetts-Dartmouth School of Marine Science and Technology
• Virginia Institute of Marine Science

Each partner surveys an assigned area using similar methods and a standardized survey design. Here, we are reporting results for the survey areas allocated to the NOAA Fisheries-based effort, led by our Northeast Fisheries Science Center. Resulting data are used for fishery stock assessments, fishery management, and biological studies.

HabCam Survey Summary

Our survey used the towed HabCam V4 vehicle and Stella, deployed from both the Hugh R. Sharp and the Henry B. Bigelow. Stella, developed in partnership with Woods Hole Oceanographic Institution, is a smaller, untethered version of HabCam designed to collect seafloor imagery and oceanographic data while deployed.

Rough seas, bad weather, and equipment failure led to 2 days of lost sea time on Leg 1, and 4 days of lost time on Leg 2 aboard the Sharp. Each leg of the cruise covered different areas. Leg 1 and Leg 3 used both HabCam V4 and Stella. Planned stations that the Sharp was not able to survey were subsequently covered by the Bigelow.

We completed approximately 1,400 nautical miles of traditional HabCam V4 transects and 200 nautical miles of Stella tracks. In all, we collected 4.5 million paired images and annotated approximately 86,000 images.

• Leg 1 on the Sharp completed 465 nautical miles of HabCam survey transect in the Mid-Atlantic and 33 nautical miles of track in the Great South Channel before stopping operations due to sea conditions. The survey also lost 1 day, returning to Woods Hole to replace a fiber optic bulkhead connector on the vehicle.
• Leg 1 on the Sharp, Stella was deployed twice in the Mid-Atlantic and covered 75 nautical miles on the first deployment and 9 nautical miles on the second.
• Leg 2 on the Sharp covered 202 nautical miles of survey transect in the Great South Channel, and 104 nautical miles on the Northern Flank of Georges Bank and in the Northern Edge. We took advantage of two short weather windows between storms. Four days were lost to sea conditions and injury on leg 2.
• Leg 3 aboard Bigelow completed 379 nautical miles of survey track in the difficult and challenging Great South Channel and Closed Area 1, and 232 nautical miles in the Mid-Atlantic.
• Leg 3 on the Bigelow deployed Stella on two missions, the first in the Nantucket Lightship area covering 71 nautical miles, and the second in the Mid-Atlantic covering 45 nautical miles.

Dredge Survey Summary

We contracted with the commercial scalloper F/V Selje out of New Bedford, Massachusetts for our scallop dredge survey. We completed all 150 planned stations and added approximately 25 more comparative stations that were also occupied by the VIMS dredge survey. Comparative catch data can help us understand dredge performance and give assessment scientists the chance to look for any catchability deviations.

All of our planned dredge stations were located in the southern New England and Georges Bank areas. The Mid-Atlantic and other parts of Georges Bank dredge surveys were conducted by the Virginia Institute of Marine Science.

Dredge Survey Stations