R-08-05 Developing Genetic Fingerprinting Techniques in Lobster Seeding Trials
As the groundfish and sea urchin fisheries declined over the last decade, fishing communities became precariously dependent on lobsters, the largest fishery in Maine. Realizing that a collapse of this fishery would have far-reaching effects going well beyond the dock, fishermen and scientists decided to take a fresh look at stock enhancement for the lobster population.
Penobscot East Resource Center in Stonington, Maine, established the the Zone C Lobster Hatchery, a community hatchery built by fishermen to enhance depleted areas within their fishing zone. Wahle and his colleage Dr. David Towle of the Mount Desert Island Biological Laboratory used an integrated approach to track the success of releasing stage V lobsters into Zone C waters, using a Before-After-Control-Impact (BACI) study of seeded experimental and unseeded control sites in Penobscot Bay, and genetic fingerprinting analysis to distinguish hatchery-reared from wild stock.
To date, a total of 285 individuals have been analyzed genetically to estimate the survival rate of hatchery-reared lobsters at three release sites, one in Stonington, Maine (Lobster Zone C), and two in midcoast Maine. DNA markers were used to determine whether settled larvae might originate from the hatchery females: approximately 8.8% of the sampled lobsters were likely hatchery reared. Despite initial high mortality rates, nursery populations were enhanced gradually over as much as four years of seeding. While the hatchery operation has been postponed due to resurgence of the lobster fishery, the Zone C community now has the information to enhance their lobster populations, should the hatchery be needed in the future.