Aerial photography a big step forward in trap density experiment

Robert Morris was one of 13 lobstermen who volunteered for the experiment. PHOTO: CARL WILSON

When Carl Wilson, Maine's chief lobster biologist, first came to Tenants Harbor looking for lobsterman to volunteer for a trap density experiment, it looked like he'd have to turn right back around empty-handed.

"After the first meeting, it seemed there wasn't much chance that it would happen at all," said Josh Miller, a 33-year old Tenants Harbor lobsterman and volunteer with the project. "By the end, we got a bunch of guys together to rally and get it done."

Even though the timing of the lobster molt threw off the set-up of the experiment, Wilson feels positive about the results of the project, explaining, "From the science side, in the end we were unable to test the impact of trap density. But the overall success story for the whole project is the cooperation. We were able to do an experiment in a heavily fished area at a time of year when it was difficult and awkward."

During the month of August, the experiment tested the relationship between trap density and lobster catch. The experiment compared the catch rates between areas with normal gear density and two designated low trap-density areas out of which volunteers removed their fishing gear. Weekly aerial photographs, underwater video recording, intensive sea sampling and logbooks filled out by participants supplied a broad spectrum of data.

The project's 13 participants shifted traps out of the two designated experimental areas, reducing trap density in those areas by 16 percent. Low catch rates throughout the inshore area at the time of the experiment caused lobstermen not volunteering with the project also to shift their traps further away from shore. The trap density in waters surrounding the experimental areas decreased by 14 percent, effectively voiding the experiment.

While the project was unable to test the effect of trap density on lobster traps, it did have some unanticipated results. The state's sea sampling program, which has been in existence since 1985, provides very detailed biological and catch data, but this information is only available at the individual vessel level. Combining the experiment's intensive sea sampling with the aerial photography gave Wilson a picture of the way the Tenants Harbor fleet fishes as a whole.

This data showed that trap density occurs in bands along the most productive ocean bottom. To a lobsterman competing with fellow lobstermen to maximize lobster catch, this may seem like an obvious conclusion. But Wilson explained that this experiment was the first time that the clustering effect has been mapped.

"Using the aerial photography was a big step forward," said Wilson. "It's a way to see that traps are clustering and not just randomly distributed." The areas of high density fluctuate according to the season and the movements of the lobsters.  Documentation of these trap density patterns can help inform future discussions surrounding trap density.

 Miller thinks the biggest lesson of the experiment came from the process of organizing participation. "I learned how difficult it is to get fishermen to do the same thing-especially a big number. By no means did we have everyone on board," said Miller.

Wilson said he was encouraged by the amount of conversation about and participation in trap density experimentation, which he describes as "controversial."

Many Tenants Harbor lobstermen had voiced concerns that the results of the experiment would be used to make a case for trap reductions.

"It turned into ‘Let's just see what happens,'" said Wilson. "It's a credit to the Tenants Harbor fishermen that they stepped up to the table rather than pushing away," said Wilson.

He and Tenants Harbor lobstermen are deciding how to best present the results of their experiment, including a presentation at the Fishermen's Forum in Rockport in March. Wilson is soliciting ideas from Tenants Harbor lobstermen as to what ideas they should test next. "It's no longer, ‘Can we conceive of doing an experiment?' The question now is, ‘What's the next experiment?'" said Wilson.

Wilson's method of encouraging input from lobstermen and holding several meetings helped the initial experiment get off the ground. "We had a long time to think about it," said Miller. "A lot of guys had a chance to talk about it at the general store or the wharf." When a long-time Tenants Harbor lobsterman and a Lobster Zone Council representative stood up in favor of the project, both of whom Miller describes as "guys we look up to and respect," they helped sway participation in the project. 

Miller needed no convincing and from the beginning was in favor of conducting the experiment in Tenants Harbor. "I was interested to see what would happen," he said.

"I think for us as an industry, we're going to have to work together with our scientists because there's too much opposition from everywhere else," he said. "It's going to have to be collaborative. We need lobstering because it's our living and the state needs it because it's a humungous industry."

Hanna Wheeler is the outreach coordinator for the Maine Lobstermen's Association. Gillian Garratt-Reed is the Island Institute's marine programs coordinator.