This is a proposed updated Action Plan in the Buzzards Bay CCMP 2024 Update.

Protecting and Enhancing Shellfish Resources

Problem

Shellfish (mollusks and crustaceans) are an important but diminishing resource in Buzzards Bay. Lobster catch began rapidly declining in the 1990s, and no young of year lobsters have been observed in Buzzards Bay in fisheries monitoring programs since 2015[1]. The collapse of the lobster fishery in southern new England is largely due to factors related to warming water temperatures and may be irreversible. Some mollusk species like soft-shelled clam have similarly declined because of warmer waters favoring increased predation by invasive and endemic crabs. Declines in bay scallop may in part be related to the loss of eelgrass habitat which is an important settling ground for spat. Declines of catch in some embayments is simply related to expanded shellfish closures because of closures resulting from elevated concentrations of indicator fecal bacteria. During the past twenty years towns have combated these trends by growing shellfish spat in upwellers or buying seed stock of oysters, quahog, and scallops to repopulate shellfishing areas. Public access to shellfishing areas is difficult in some towns.

While the acreage of shellfish bed permanent closures had mostly declined through about 2015 because of water quality improvements, after 2018 many new areas were closed because of FDA National Shellfish Sanitation Program rules related to mandatory areas around marinas and mooring field. Additional FDA rules adopted in Massachusetts in 2023, now require more expansive mandatory closures around municipal wastewater treatment facility outfalls. The new requirements will result in the closure of tens of thousands of acres of shellfish growing areas in Buzzards Bay as each wastewater outfall is evaluated. Recreational shellfishing areas has been eliminated in New Bedford and appreciably reduced in Dartmouth and Fairhaven. New closures are expected as outfalls in Dartmouth, Marion, Wareham, and Bourne are evaluated. The boundaries of these mandatory closures around wastewater outfalls are based on theoretical models of water circulation, and no single model or methodology is defined. These closures will affect both commercial and recreational shellfishermen. Exacerbating the problem, funding for shellfish propagation and relay programs has been reduced.

The Massachusetts Division of Marine Fisheries (DMF) implements shellfish bed management based on ambient water quality in shellfish beds and a mostly visual evaluation of potential pollution sources along the coast (Shellfish Sanitation Survey Program). Additional coordination and collaboration between DMF and municipalities could help reduce closures through the expansion of rainfall conditional closure programs. Reduced municipal reporting of recreational shellfish catch through surveys and recreational permits sold hampers assessing impacts of water quality declines and loss of shellfish resource availability.

This action plan narrowly addresses steps to enhance the availability and productivity of shellfish resource areas. It compliments other action plans that target specific pollutants and impacts, especially Action Plan 3 Managing Stormwater Runoff and Promoting LID, and Action Plan 1 Managing Nitrogen Sensitive Embayments.

Goals and Objectives

Changes: The goals and objectives were re-worded improve clarity and readability and to include climate objectives. Four new objectives were added to clarify actions needed to meet stated goals.

Goal 2.1. Increase availability of shellfish resources for recreational and commercial use.

Goal 2.2. Restore habitat to increase the abundance and distribution of shellfish resources.

Objective 2.1. Support efforts to prevent new shellfish resource areas closures, and open priority resource areas.

Objective 2.2. Increase the ability of the Massachusetts Division of Marine Fisheries to carry out the sanitary survey program, comply with the National Shellfish Sanitation Program, and provide technical assistance to municipalities to better manage shellfish resources.

Objective 2.3. Increase the capacity and commitment of municipalities to remediate pollution sources that are contributing to shellfish bed closures or not meeting the watershed’s bacterial total maximum daily load limits.

Objective 2.4. Where justified and supported locally, expand the use of the rainfall conditionally approved classification to reduce seasonally closed or prohibited shellfish areas.

Objective 2.5. Eliminate pollution sources and disturbances contributing to the permanent loss of shellfish habitat.

Objective 2.6. Expand programs to propagate, seed, and relay shellfish.

Objective 2.7. Promote and support activities to enhance and restore of shellfish habitat, especially efforts that ensure shellfish resources remain resilient to changes in habitat and water quality caused by climate change, or concurrently ameliorate coastal eutrophication. (Split from previous objective)

Objective 2.9. Promote research to better define the relationship between temperature and precipitation and shellfish water quality indicators and associated habitat (e.g., eelgrass beds). (New)

Objective 2.10. Implement pH and carbonate system monitoring around Buzzards Bay to understand changes over time and impacts to shellfish and other living resources. (New)

Objective 2.11. Support the use of sound hydrodynamic models to define mandatory shellfish closures around wastewater outfalls. (New)

[1] See https://www.asmfc.org/species/american-lobster and Atlantic States Marine Fisheries Commission Review Of The Interstate Fishery Management Plan For American Lobster (Homarus Americanus) 2022 Fishing Year