Are Coastal Deep Water Zones in the Northeastern Gulf of Maine, Essential Broodstock Habitats for the American lobster?  (Year 1 of 1) Project Number: NAGL-99-02 Principle Investigators: Steneck, R. S., and M. J. Fogarty Region(s): Coastal Maine The American lobster has been the target of intense fishing pressure for over a century but stocks have not collapsed. In fact, over the past decade lobster abundances doubled throughout their range. Today, lobsters are the single most valuable marine resource in New England. In Maine alone, their harvested value exceeded 180 million dollars in 1999. With economic multipliers of bait, boats, and tourism the lobster industry is worth billions of dollars to the region. Healthy stocks require healthy reproductive populations. Clearly stocks are not currently reproductively limited. However, to maintain stocks we need to know where the reproductive segment of the population resides. More importantly, we need to know the location of the segment of the reproductive population that supplies most of the larvae that settle into the prime nursery grounds. Past research indicates clearly that lobster larval settlement is highest in coastal areas around and west of the mouth of Penobscot Bay. The Eastern Maine Coastal Current (EMCC) flows along the coast from the mouth of the Bay of Fundy to this nursery region. This NURP study sought to quantify the distribution and abundance of reproductive lobsters in areas east and west of Penobscot Bay. The hypothesis was that regions to the east of the bay may be the larval source for larvae that settle in the western regions (a larval "sink"). We targeted our research to coincide with the time of peak larval abundance. We conducted systematic benthic surveys using a remotely operated vehicle (ROV) at 45 sites. Based on the distance covered and area observed, we determined the abundance of all lobsters encountered. We also conducted plankton tows every evening do determine the distribution, abundance and location of newly hatched 1st stage larvae and ready to settle 4th stage post-larvae (stages 2 and 3 are not found in the surface water we sampled).   Results of the project to date: We tagged several thousand egg-bearing lobsters were found to migrate offshore in the Fall and onshore in the Spring. They were concentrated in near-shore coastal sites around the time of the egg hatch. We targeted these regions for our ROV surveys. Remotely operated vehicle results show the highest abundance of juvenile lobsters were found in the vicinity of Mt. Desert and areas to the southwest (Penobscot Bay and Pemaquid). Reproductive lobsters, however were by far, most abundant in the vicinity of Grand Manan Island in the mouth of the Bay of Fundy. Larval tows along transects traversing the EMCC show a majority of early stage larvae in eastern regions, close to where abundant reproductive lobsters were found. Late stage (4th stage) post-larvae were most abundant and moved closest inshore near the Penobscot Bay nursery grounds. Benefits of this research to society: We are getting very close to being able to identify the essential broodstock habitat for the American lobster in the Gulf of Maine. If it is confirmed that some of this broodstock reside in Canadian waters, then managers will have to not only consider U.S. state and federal waters but Canadian populations as well for comprehensive management of this species. Future plans: We need some assurance that our 1999 snapshot of broodstock lobsters and their associated larvae are not anomalies. Further research on this is warranted to identify and take steps to protect the essential broodstock habitats for the American lobster. Leg 1    Begin Date: 7/29/1999   End Date: 8/8/1999   Support Vessel/Platform: R/V Connecticut System Ops Days Dives Dive Time (hrs) Depth (m) KRAKEN (MAXrover MKI) 10 45 44.92 87.5 Keymap: Location of Project Dives: Legend: KRAKEN (MAXrover MKI)

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