Science for Everyone

DMR Lobster Settlement Survey Dives


I spent Friday Oct 18 and Monday Oct 21 helping (by sorting samples) DMR scientists Robert Russell and Carl Wilson, who are conducting their annual dive survey of larval lobster settlement rates at 50 sites along the Maine coast. At each site they sampled 12 quadrats via underwater suction sampling. Samples were then sorted and processed on the boat. The suction sampler pulls up all loose sediment and other organisms, so we needed to sift through it and pull out any lobsters and crabs we found. Many of the samples also had shrimp, urchins, seaweed, brittle stars, marine worms, asst. shells, and occasionally rock gunnels and cunner (fish). Once the sample was sifted, we measured the lobsters and crabs carapace length, and we also collected data about the lobster's sex and number of claws.

The boat they used for these dives was the 38' Lady Anne, operated by Sea Ventures Charters, Captained by Dave Sinclair.

Some of the sites we visited during these surveys were Head Harbor at Isle Au Haut, Ragged Island, Allen Island, Matinicus, Hurricane, and Monhegan


Overall, Carl and Robert said that they were seeing far fewer settler-size lobsters across all of their sites than in previous years (this survey has been going on for 22 years). For example, we only found 6 settlers from the 5 sites that were surveyed on Friday, when in the past Robert and Carl have found 4-5 settlers per site in that area.

The data from these surveys will feed into the American Lobster Settlement Index.

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