Bacteria, Pesticide & More Blamed for Lobster Deaths
By Nicole Pressly Wolf

The mysterious case of the die-off of the once thriving lobsters in the Long Island Sound is solved. According to a complex three-year, multi-million dollar research investigation, stressful environmental conditions and disease were the culprits. The massive 1999 die-off, and the subsequent failure of the lobsters to recover, posed an enduring mystery to scientists, industry and regulators, with huge economic and ecological implications to the area.

The 24-page report titled “Responding to a Resource Disaster: American Lobsters in Long Island Sound 1999-2004,” was jointly authored by Nancy Balcom of Connecticut Sea Grant, University of Connecticut, and Penelope Howell, Marine Fisheries Division, Connecticut Department of Environmental Protection. It provides a final summary report for the Long Island Sound American lobster health research initiative, which was managed by the bi-state and federal Steering Committee for Lobster Disease Research.

In 2000, at the request of the governors and congressional delegations of New York and Connecticut, the U.S. Department of Commerce declared the lobster fishery in Long Island Sound “a commercial fishery failure due to a resource disaster.”

Congress appropriated $13.9 million for economic assistance, resource monitoring and assessment, and research into the potential causes of the event. The Connecticut and New York state governments, the NOAA National, New York and Connecticut Sea Grant Programs, the NOAA National Marine Fisheries Service, and the U.S. Environmental Protection Agency together contributed an additional $6.6 million to this effort.

A national study investigating the potential cause(s) of the lobster mortalities was undertaken by the steering committee, a sub-committee of the Atlantic States Marine Fisheries Commission's (ASMFC) Lobster Management Board. Eleven representatives of state and federal regulatory agencies, Sea Grant, and the lobster industry comprised the Steering Committee. Twenty-one projects involving 65 scientists at 30 institutions nationwide investigated the effects of environmental stressors and disease on American lobsters over three years, according to the Sea Grant website.

They concluded that adverse environmental factors such as warmer water temperatures, presence of pesticides and disease caused by the presence of a microscopic organism (known as a “paramoeba”) produced such stressful conditions that many lobsters died and the population in western Long Island Sound collapsed. The research findings summarized in this report were announced in fall 2004 during the fourth LIS Lobster Health Symposium, held in Stony Brook, New York.

The results will provide lobster biologists and resource managers with extensive new information and tools to help guide environmental management decisions. For example, a new fatal disease in lobsters, paramoebiasis, was identified. This disease is caused by parasitic microorganisms attacking lobster nervous tissue. Based on laboratory studies, the deleterious effects of several pesticides on different life stages of lobsters have been described. These pesticides were used to control mosquitoes carrying the West Nile virus in 1999 and subsequent years.

The results of the research, however, did not conclude that the pesticides were the direct cause of the die-off. Rather, it suggested that they could have provided additional stresses to lobsters in relatively small areas in western Long Island Sound during an otherwise very stressful summer. A series of new immunological tools developed during the study will help lobster biologists better determine the health of a lobster in the future. In summary, the effects of stressful environmental conditions on the health of lobsters are now better understood.

The research and economic assistance programs have now ended, and attention has fully turned toward the management and recovery of the remaining lobster population. Some $10.8 million has been expended on research and resource monitoring; $9.7 million has been spend on economic assistance.

“Now we’re in much better shape to be able to look at things and anticipate when and if it may happen again,” said Jack Mattice, director of the New York Sea Grant Institute and current chairman of the steering committee.

Copies of the report are available by contacting Connecticut Sea Grant at (860) 405-9127.