Atlantic cod is a classic New England fish, found everywhere from roadside fish-and-chip stands to the Massachusetts State House. Under the Magnuson–Stevens Act, NOAA Fisheries fosters the long-term biological and economic sustainability of marine fisheries, including rebuilding overfished stocks. Currently Atlantic cod is considered overfished and rebuilding plans are in place to promote population growth. We recently teamed up with recreational fishermen and other partners to learn more about this iconic species.
Advancements in Understanding Cod Populations
The latest model of cod stock structure based on scientific advances in genetics, tagging, and biological characterization shows there are five biologically distinct cod populations from New Jersey to Canada, and four stock units. This new model allows managers to better tailor management to the specific needs of each stock to help populations recover.
Recreational Biological Sampling Fills Data Gaps
In light of these advancements, stock assessment scientists needed more biological data from the recreational fishing fleet. NOAA Fisheries teamed up with members of New England’s recreational for-hire fleet, the New England Aquarium, Pelagic Strategies, and the Atlantic States Marine Fisheries Commission to fill those data gaps. The pilot study is called the Recreational Biological Sampling Program, or RecBio.
More location-specific catch data will provide a clearer picture of cod populations, particularly in the Western Gulf of Maine and Southern New England. Cod are prized by recreational fishermen. Recreational fishermen differ from commercial fishermen in where they fish, the gear they use, and the regulations to which they’re subject. The composition of their catch may vary compared with commercial fleets.
Captain Rick Bellavance, chair of the New England Fisheries Management Council and RecBio co-founder and participant, explained, “The RecBio cooperative research initiative paired fishermen like me with scientists directly engaged in the stock assessments of Atlantic cod. We worked together to figure out a way to collect the important biological data needed for a new cod assessment.”
During the first year, from November 2023–2024, 12 participating for-hire captains collected data from more than 3,000 fish while fishing in the Western Gulf of Maine and Southern New England stock areas. They recorded:
- Length with photo to verify measurement
- Kept or released
- Date/time caught
- Precise location
Digital App Makes Data Collection Seamless
With support from The Nature Conservancy, Harbor Light Software tailored the existing AnglerCatch fishing app as a portal for captains to enter their data using a smartphone or tablet. RecBio Captains tested and provided feedback to design an app that works in the field and gives the scientists the data they need in a timely and accurate way.
Mike Pierdnock, Stellwagen Bank Charter Boat Association president, New England Fisheries Management Council member, and RecBio co-founder and participant said, "The recreational community are the eyes and ears on the water. We can identify expanding or shifting stocks at locations that in some instances are not accessible to either the commercial fleet or fishery survey vessels."
When a fisherman harvests a cod, the participating captain gives it a unique barcode to match the data submitted to the app. The captain freezes the fish’s head at the end of the trip. The science team then extracts the otoliths (ear bones that contain growth rings). Scientists count the rings of the otolith to estimate the age of the fish. This allows them to understand the demographics of cod caught recreationally. Finally, captains collect fin clips to allow scientists to study the genetics of each cod population.
Better Data Improves Chances for Cod Recovery
The team collected otoliths and fin clips from more than 300 cod in the first year. With additional funding from The Nature Conservancy, RecBio expanded in spring 2024 to include two captains collecting winter flounder length data in the Gulf of Maine for-hire recreational fishery.
The science team shares the captains’ data with stock assessment scientists quarterly to ensure its timely integration into the stock assessment process. This data will fill critical gaps to inform more effective cod and winter flounder assessment and management.
Anna Mercer, chief of the Northeast Fisheries Science Center’s Cooperative Research Branch, noted that RecBio could be a model to fill similar data gaps for other recreationally-important species. The team hopes to expand the program to allow private angler citizen scientists to collect and submit data as well.
Of the program, Bellavance emphasized, “I gladly accept any chance I get to pitch in with better science for better management. Working in collaboration benefits fishermen like me and scientists alike. Everyone learns something; it’s a win-win situation.”
