Methoprene prevents mosquito larvae from molting and developing into adults. Methoprene similarly affects lobsters' reproductive cycles and could be causing female lobsters to shed their shells before their eggs have hatched, University of Connecticut pathobiologist Richard French said Wednesday. Methoprene has been used in New York for years without appearing to damage the crustaceans, so it is unlikely that it was a primary cause of the massive lobster die-off that occurred last fall in Long Island Sound, French said. But already this year, officials plan to drop 135,000 pounds of methoprene-containing briquets in storm drains and catch basins in New York City and as much as 80,000 pounds in Westchester County to prevent the spread of West Nile Virus, a spokesman for the New York Department of Environmental Conservation said Wednesday. The virus killed seven people in New York last fall.
Lobsters are distantly related to insects, which is why they can be affected by the larvicide.
Lobstermen in Connecticut and New York became alarmed last fall when, for the first time, they noticed egg-bearing lobsters molting too soon. The larvicide has been used in Nassau and Suffolk counties on Long Island in past years, although the quantities were not available Wednesday. Methoprene is marketed under the brandname Altosid. Although there is no evidence that the larvicide is seeping into the Sound, the New York agency will likely study the issue, spokesman Mark Lowrey said. All rights reserved.