Genetics/Hatchery/Resettlement

We are an organization whose mission is to energize and facilitate responsible community-based fishery management, collaborative marine science, and sustainable economic development to benefit fishermen and communities in Penobscot Bay and the Eastern Gulf of Maine. 

The Zone C Lobster Hatchery originated through the concerns and long-term interest among fishermen to participate in an active resource enhancement program.  The hatchery is funded and overseen by fishermen in Zone C.  It was built incorporating state of the art techniques and equipment developed by Beal and Chapman (2001) and refined during hatchery activities.

The Zone C Lobster Hatchery is currently the largest scale U.S. operation to date using current technology designed to achieve the highest observed survival rates (up to 60%) for rearing lobsters to stage IV.  In three seasons of operation, the hatchery has released over 210,000 stage IV and V lobsters in more than 24 sites in the nine Zone C districts. 

In 2010 hatchery production has been suspended but in a more typical season, the following operations take place:

Phase 1 – Egg Collection:  Egg-bearing female lobsters with ripe eggs are trapped by specially-licensed fishermen from each of the nine districts in Zone C and taken to the hatchery as needed Fishermen collect late-stage eggers, identified as having eye spots and a lighter color. 

Phase 2 – Hatchery Phase: Females delivered to the hatchery in the spring are dipped in dilute Provodine to remove epiphytes, and held in a communal tank receiving chilled (5°C), re-circulating seawater.  The holding tank enables better management of larval production during the season by slowing down egg maturation.  Females selected for immediate larval production will be placed in individual holding tanks at 18°-20° until their eggs are hatched (average 11 days).  As larvae are released from the female they are periodically transferred to larval tanks enriched with brine shrimp and algae.  Once the eggs have hatched, the female is V notched and released. 

Algal cultures grown in the hatchery are fed to the lobster larvae with brine shrimp.  The larvae will be reared to stage IV or V in the hatchery prior to release.

Phase 3 – Release Phase:  Juvenile lobsters are taken on board commercial lobster boats and released on appropriate juvenile habitat within the Zone C management area.  The release sites are chosen collaboratively by fishermen in the districts, hatchery staff, Hatchery Steering Committee, and the scientific advisors.  The release process involves standard techniques developed and used by Dr. Brian Beal, Dr. Richard Wahle and others.  This involves transporting the small lobsters on moistened paper towels, chilled with ice in a cooler, re-hydrating them onboard in ambient water and, when active, releasing them onto appropriate habitat through a weighted polyethylene hose.

Phase 4 – Resettlement Monitoring Phase: During the 2010 season, Dr. Wahle’s dive research team will continue to monitor the resettlement sites

RESETTLEMENT PROGRESS REPORT 2009

As of the end of October2009, Dr, Rick Wahle (Bigelow Laboratory For Ocean Sciences) completed the second and final field season of the Sea Grant sponsored project. Prior to the Sea Grant support we had conducted releases of hatchery-reared stage-5 lobster first at one site in 2006, and then a second site in 2007, both with paired control sites where no hatchery lobster were released. Sea Grant support enabled us to add two more release and corresponding control sites in 2008. Therefore, as of October 2009 we had conducted four consecutive years of releases and diver surveys at the longest-standing site.  Both suction sampling and visual surveys have been conducted at all sites by Dr. Wahle’s team. The suction sampling protocol each year has included pre-release suction sampling, followed by three successive post-release samplings (1 wk, 1 mo, and 2 mos). All told, since 2006 some 21,000 stage 5+ lobsters have been released among the 4 release sites.  Preliminary results suggest that post-release recoveries of hatchery-reared lobsters has been on the order of 5-10% of the numbers released. Genetic fingerprinting analysis will help confirm these estimates. 

GENETIC ANALYSIS

Lobster tissue samples from field and hatchery collections enable Dr. Gerlach (University of Oldenburg) and her graduate student, Jana Deppermann, to conduct the genetic fingerprinting analysis, the centerpiece of this study. Genetic analysis of the first year (2008) samples made clear the need to develop new markers to refine the assignment of field-caught juvenile lobsters to hatchery mothers. In addition to the previously used set of 6 EST-linked microsatellites, we established three new microsatellites for the maternity analyses. With this extended set of nine markers, to date we have analyzed 290 field-caught juvenile lobsters and hatchery females.  We are currently developing a set of size-based and genetic criteria for assigning the source of field-caught lobsters. Tissue samples from 2007 and 2008 are currently being re-processed for these additional markers along with the new samples from 2009 samples. We aim to have the final analysis during 2010.

SENTINEL FISHERY

Starting in Summer 2010 we are operating  an experimental fishery to learn valuable information about cod, hake and pollock in eastern Maine, and to see if depleted groundfish stocks in the region will be able to support a small scale hook fishery in the future .  The project falls under our Downeast Groundfish Initiative

WHY?

  • No one is currently groundfishing in eastern Maine, so the stock assessments for groundfish may not be as accurate as they should be.  Robust stock assessments rely on catch data from fishermen.  Therefore, we are working with fishermen in eastern Maine to catch fish and learn about the stocks.
  • For the past two decades, groundfish stocks on eastern Maine’s coastal shelf have been severely depleted.  This is an opportunity to see if the fish stocks may be rebuilding.
  • We believe that groundfish need to be managed at a finer, more local scale.  The Sentinel Fishery will allow researchers to see how data collected at a fine scale may affect the current stock assessments for several groundfish stocks.

HOW?

  • Fishermen will use their own groundfish permits and fish within the Northeast Coastal Communities Sector.
  • Penobscot East will lease quota from its Permit Bank to fishermen to support this project.
  • Fishermen will use hooks only to ensure protection of critical habitat on the coastal shelf.
  • On-board observers will record groundfish catch at the location where the fish are caught. They also note size, weight and species.
  • Fishermen will sell their catch through local markets, such as a community supported fishery (CSF) e.g. COMMUNITY FISH.