Fourth-stage lobster

MarineFisheries uses a 4-tiered approach to monitoring the American lobster resource and fishery in Massachusetts' coastal waters. The Coastal Lobster Investigations Project is directly responsible for conducting an annual coastwide commercial lobster sea sampling program which provides biological and catch/effort data from six coastal regions during the major lobstering season, May-November (since 1981).

A second annual sampling effort for EBP (early benthic phase/juvenile) lobsters is conducted by SCUBA through suction sampling in order to generate density indices of newly settled post-larval lobsters (since 1995). This effort also delineates coastal habitat important to the settlement of these juveniles and thereby provides insight into potential impact of proposed coastal alteration projects.

Year-round bottom temperature monitoring (since 1988) is conducted with programmable electronic recorders at various depths at seven coastal sites, north and south of Cape Cod. Recorders are replaced annually by SCUBA.

Data from two additional projects also contribute to stock evaluations. These include the MIS and Fisheries Statistics Project which collates catch reports submitted by commercial fishermen to provide landings and effort statistics on a monthly and area basis (since 1967) and the Resource Assessment Project which provides, through a bottom trawl survey, relative abundance information on lobster and other species (since 1978).

Time series data generated by these sampling efforts together with those from other states and National Marine Fisheries Service (NMFS) allow us to contribute to coastwide stock assessments as a function of our participation on the Atlantic States Marine Fisheries Commission (ASMFC) American Lobster Technical Committee.

Our ancillary research efforts have defined size at maturity, fecundity, weight-length relationship, morphology, and migration patterns in Massachusetts' coastal waters. Gross pathology is also monitored.

The uniqueness of the Massachusetts coastline, with its role in providing a temperature barrier at the southern end of the Gulf of Maine, profoundly affects many marine species. The potential effects of the geological and hydrographical characteristics of our coastal environment on lobster reproductive ecology are apparent and strongly influence recruitment and subsequent commercial catches. We have discerned geographic variation in morphology, size-frequency, migratory behavior, growth rate, fecundity, and maturity. As a result, three lobster groups (southern Gulf of Maine, outer Cape Cod, and Buzzards Bay/Southern Cape Cod), differing in major population descriptors, are defined by our data.

Project personnel serve as technical advisors to ASMFC Lobster Conservation Management Teams crafting regional lobster management plans. They also serve on the New England Fishery Management Council Red Crab Plan Development Team and the ASMFC Northern Shrimp Technical Committee.