To measure the success of the Zone C Lobster Hatchery, we must closely monitor the lobsters released: Do they survive? After our first season, we are starting to learn how to test this.

Bellatuono of Bigelow Lab prepares to dive.

In April 2006 fishermen and scientists worked together at a collaborative workshop to develop a program to monitor some of the release sites using divers for the first years when the lobsters are too small to trap, even in juvenile traps. Juvenile lobsters are tough to monitor—each is no bigger than a penny and too small to tag.

There are four pairs of research release sites, eight sites in all. Of each pair, one site is a control site, which does not receive any lobsters. Each pair is in a different district of Zone C. The sites are surveyed one week prior to the release of lobsters, the day after releases, one week, one month and two months after release.

A dive flag flies on the boat of a lobsterman donating his time to help science divers monitor hatchery releases.

During the summer of 2006, Dr. Rick Wahle of Bigelow Laboratory in Boothbay Harbor led a team of research divers to monitor the hatchery releases. The dive team used two techniques (visual and suction sampling) to check the selected survey sites for proper habitat, other lobsters and associated biota, such as crabs.  The plan is to genetically test any lobsters that are collected against samples taken from the hatchery stock prior to release. The number of matches would tell us how many hatchery-reared lobsters have survived or at least remained within the release location.

It appears from these early results that stage IV post-larval lobsters (~14 days old) may not settle where they are released, whereas stage V lobsters (~28 days old) do. While this may not have any impact on the survival of the stage IV lobsters, it simply implies they would not be able to be tracked as planned. 

The research is still inconclusive and may take several years to complete, but a great deal has been discovered about larval lobsters and their behavior after release.   Next season, in addition to raising and releasing stage IV lobsters, the hatchery will try raising stage V lobsters and continue to gain more knowledge towards answering the question that has eluded scientists for more than a decade:  Can hatchery-reared lobsters be a useful tool to support the lobster fishery’s productivity and enhance depleted stocks?