The state Department of Conservation and Recreation is studying the impact that chemicals would have on the endangered Boreal Turret Snail before applying herbicides at Lake Cochituate.

http://www.metrowestdailynews.com/localRegional/view.bg?articleid=107187

Metro West Daily News (Massachusetts)

August 27, 2005

Lake Cochituate herbicide plan slows to a crawl

By Claudia Torrens / Daily News Staff

NATICK -- A tiny and slippery creature at Lake Cochituate could change an upcoming state plan to use herbicides to control milfoil at the lake.

The state Department of Conservation and Recreation is studying the impact that chemicals would have on the endangered Boreal Turret Snail before applying the herbicides, said Bob Bois, the town's environmental compliance officer.

 "They are looking at this issue before going on," said Bois.

The snail, also known as Valvata sincera, is listed under the Massachusetts Endangered Species Act as endangered. The state's list of snails considers it locally rare and has a record of it in the Sudbury-Assabet-Concord Rivers watershed.

Mike Gildesgame, the DCR's acting director of water resources, could not be reached for comment to confirm the study of the herbicide impact.

The state proposes using chemicals to treat the entire lake and not just certain spots as a more drastic way of controlling milfoil, which is spreading aggressively, said Joe O'Keefe, assistant secretary of environmental affairs. The chemicals are fluridone, a white crystalline solid with no odor, and diquat, a general use herbicide.

A group of residents opposed to herbicides has appealed the state plan, claiming the chemicals will kill the endangered creature.

"They adversely affect the snail," said Martin Levin, the lawyer for the two dozen residents.

Levin said, although he could not confirm it, his understanding is that the state has hired an expert to determine the impact of chemicals on the mollusk. He and his clients counter that herbicides pose risks to the lake's animals and plants and threaten Natick's drinking water.

The residents appealed the first herbicide plan the state put forward in 2003 to control milfoil. That plan said Lake Cochituate was "a habitat for the snail," said Levin. When the appeal was denied last year, the group challenged that decision to the state Division of Administrative Law Appeals.

Now, the DCR has set aside the appeal because the milfoil situation "is much more severe," said O'Keefe. The state is working now on the new plan proposing the use of fluridone and diquat.

In a letter sent to the Natick Conservation Commission in May 2003, the Natural Heritage and Endangered Species Program said the application of herbicides would not harm rare species.

"It is our opinion that this project, as currently proposed, will not adversely affect the actual habitat of rare wildlife," said the letter.

Levin said, however, that after a public records request, a Natural Heritage official confirmed that no evaluation had been done on whether herbicides would harm the snail.

"He stated that the (Natural Heritage program) does not have the resources to conduct such searches," said Levin, when he allegedly asked the official whether the species still inhabited Lake Cochituate.

O'Keefe said the snail, which has a shell up to 5 millimeters in diameter, "may or may not change the plan."

 "We are looking at the entire picture as it stands," said O'Keefe. "We are comparing the situation to last year. We want to make sure herbicides are safe to use."

Levin has cited in the appeal the work of Emily Monosson, a research toxicologist, who says the herbicides will kill the snail.

"Since Valvata sincera lives and breeds in association with aquatic vegetation, killing the vegetation will kill any associated Valvata," Monosson said in a report.

Claudia Torrens can be reached at 508-626-3976 or ctorrens@cnc.com