Skip navigation
RES_ST_cod tag_a1
RES_ST_cod tag_a2

GMRI lead investigator: Shelly Tallack

GMRI data technician: Sarah Whitford

Partners: Over 30 scientists across the following tagging organizations: the Department of Fisheries and Oceans (DFO), The Island Institute, Maine Department of Marine Resources (ME DMR), the Cape Cod Commercial Hook Fishermens Association, Manomet Center for Conservation Sciences (Manomet) and the School for Marine Sciences and Technology (SMAST).

In addition, 107 commercial and/or recreational fishing vessels worked in partnership with each of these scientific organizations.

Completion date: December 2002 - June 2006 (original contract, Years 1-3); July 2006 through December 2007 (current contract, Year 4).


Atlantic cod total stock biomass estimates have shown a steady decline since the 1960s (NEFSC 2001) and the effects of this decline on the fishing industry have been dramatic. Recently, however, there have been increases seen in some of New England's key fishing grounds showing promise for the future. There is consensus among industry and the scientist community that the distribution and movement of cod in the Gulf of Maine, Georges Bank and southern New England regions is not perfectly understood and that greater insight into current distribution and migration patterns of Atlantic cod is important for management efforts to rebuild cod stocks.

One way to address questions of migration is by tagging, releasing, and recapturing fish. There had not been a broad-scale tagging effort on cod in U.S. waters since at least 1959, and there is a possibility that movement patterns described by earlier studies have changed. Despite extensive tagging done between 1984 and 1997, primarily in Canadian waters of Browns Bank, northeast Georges Bank, Grand Manan, and southwest Nova Scotia, there are still large sections of the Gulf of Maine and Georges Bank for which up-to-date tag recapture data are not available.

As a neutral, independent entity, in December 2002 the Gulf of Maine Research Institute was awarded a contract by the National Marine Fisheries Service to provide overall project coordination and data collection for an international team of researchers. The Northeast Regional Cod Tagging Program (NRCTP) represents the largest cod tagging program initiated to date along the eastern seaboard of the North American continent. This region-wide partnership of fishermen and international researchers have worked together to achieve four primary objectives with both socio-economic and biological emphases, as outlined below.

During the course of the NRCTP, both program partners and funders have recognized the need to maintain the outreach and data collection infrastructure, and continue with analysis of the wealth of cod tagging data already collected. To this end, and also in acknowledgement of the success of this Program to date, a new contract was granted in July 2006 which extends the NRCTP into a fourth year, through December 2007.

GMRI continues to manage the NRCTP but has also become the primary analytical body for the Programs large dataset; GMRI continues to collaborate closely with the stock assessment team at the Northeast Fisheries Science Center (Woods Hole) and the Department of Fisheries and Oceans (St. Andrews, N.B.) with the aim of working with and delivering the data in a form most relevant for application in future cod assessment and management.

Primary research objectives (Years 1-3):

  • Develop a collaborative cod tagging program between scientists and fishermen in the Gulf of Maine region, including Canada;
  • Tag and release ~100,000 Atlantic cod throughout the study area;
  • Make the data available to the public via an online GIS mapping interface;
  • Obtain and analyze data from tag recaptures to improve our understanding of cod distribution, movement and growth;
  • Establish a preliminary understanding of cod movements and stock structure that will enable us to develop testable hypothesis for continuing tagging studies.

Primary research objectives (Year 4):

  • Develop historical tagging databases which mirror the Northeast Regional Cod Tagging Programs database structure, in order that all major tagging datasets for cod in the NE region are in one master database format for more efficient future use.
  • Continue analysis, ensuring that stock assessment data requirements are met as much as the this Programs data can provide.
  • Continue to disseminate findings to industry and other stakeholders with an emphasis on a results-oriented, glossy mass-mailing and an industry/science workshop (see below).

Primary research objectives (Year 5-6):

  • Maintain the core tagging infrastructure to continue outreach initiatives and collection of tagging recapture data.
  • Continue with advanced analyses and preparation of the NRCTP cod tagging data for inclusion in the 2008 Atlantic cod stock assessment.
  • Design and prepare for future advanced cod tagging research to target specific gaps in regional cod migration information.


Support: Cooperative Research Partners Program, NOAA Fisheries, New England Fisheries Management Council & the Research Steering Committee

Scientific partners: Canada Department of Fisheries & Oceans (DFO), Island Institute (II), Maine Department of Marine Resources (DMR), Manomet Center for Conservation Sciences (Manomet), Cape Cod Commercial Hook Fishermens Association (CCCHFA), and The School for Marine Sciences and Technology, UMASS, Dartmouth (SMAST).

Industry partners: Over 250 fishermen have participated in the release of tagged cod and over 1000 individuals have reported tags during the course of the Program please keep these coming!!!

Database and mapping site development: Northern Geomantics Inc.

Analysis - review & assistance: Northeast Fisheries Science Center (Mark Terceiro, Ralph Mayo, Loretta OBrien & Tim Miller), Canada Department of Fisheries and Oceans (Don Clark), The School for Marine Sciences and Technology (Steven Cadrin), and CSIRO Marine, Hobart, Australia (Alistair Hobday).