Martha’s Vineyard conch fishermen seeking to lower this year’s minimum catch size were dealt a setback last week when the Division of Marine Fisheries (DMF) declined to take emergency action for the remainder of the 2017 season.
The ruling was made in response to a July 10 public meeting in Tisbury, when DMF officials came to listen to Island fishermen and wholesalers, who said the 2017 minimum-width size increase from 3 inches to 3⅛ inches, and a new measuring technique — which they believed was selecting larger than the 3⅛-inch minimum shell — was putting them out of business.
For years, a gauge was used to measure the conch shell at its widest point, parallel to the sides. This year, in an attempt to increase simplicity in measuring the oddly shaped animal, DMF changed the measuring method to “any orientation” with a 2⅞-inch gauge. “It added a more abstract element, and created a blurry area,” veteran fisherman Tom Turner told DMF officials. “Last year it was simple, a 3-inch gauge, pull it along the centerline at its two widest points. If it slides through, it’s sublegal.”
Instead of the new minimum size and measuring technique reducing their catch by 16 percent, as projected by DMF, fishermen reported reductions from 30 to 60 percent.
“We’re not trying to wipe out the conch; we need something we can work with,” fisherman Todd Godell said. “This is about just holding on.”
Danny Chan, owner of Aqua World, the largest conch wholesaler on the Island, told DMF officials that his inventory was down 50 to 60 percent this year.
Several fishermen at the meeting asked why Massachusetts was the only state in New England that regulates conch — more accurately called knobbed whelk and channel whelk — while populations in Rhode Island and Connecticut appear to be doing fine.
Responding to the DMF ruling on Monday, veteran fisherman Tom Turner told The Times, “It’s not like conch population is going down. We’re not seeing the last of the buffaloes with the conch; they’re plentiful.”
DMF officials did not respond to repeated requests from The Times for an explanation of the ruling.
Conch is the most valuable fishery on Martha’s Vineyard. Last year there was a 14 percent drop in pounds harvested. According to the National Marine Fisheries Services, in 2015, 681,000 pounds were harvested here, with a value of $1.6 million. In 2016, 589,000 pounds were harvested, with a value of $1.4 million.
Recipe for disaster
Vineyard fishermen were initially apprised of DMF plans this February at a public meeting in Tisbury. Deputy director Dan McKiernan and Director David Pierce presented a plan that increased the minimum size from 3 inches to 3 3/16 inches. The minimum was later reduced to 3⅛ inches.
“We think the whelk is on a trajectory for disaster,” Mr. McKiernan said at the meeting. “I think the general consensus is that the size distribution is dropping, and we are concerned about the long-term health of the stock. We need to achieve a minimum size where at least 50 percent of the [harvested] whelks are sexually mature.”
The DMF based its decisions on two studies, done in 2010 and 2015, that concluded that conch need to be 3⅞ inches in width to reach the 50 percent maturity benchmark, meaning one of every two conch that size can reproduce.
“The whelk population has declined pretty dramatically since 2004,” DMF biologist Bob Glenn said, adding that it takes seven years for a whelk to become sexually mature.
In the big picture, the DMF has proposed to increase the minimum size by ⅛ inch every two years after 2017, until reaching the 3⅞ target size in 2029.
Mr. Turner questioned the logic of harvesting only big conch. “If we keep increasing sizes, and target only large conch, aren’t we killing the golden goose by targeting spawning mass?” He said the sweet spot for conch is between 3⅛ and 3½ inches. “That’s where we make our money,” he said. He also opposes slot limits, setting a maximum and minimum size, because larger conch have soft spots in their shells and would probably not survive catch and release.
“We can’t lose our livelihoods on measuring not being done properly. If they want to get a true population count, they should be here between September and November. There need to be more studies,” Mr. Turner said.