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by James Acheson, Professor of Anthropology and Marine Studies, University of Maine and author of
The Lobster Gangs of Maine
Men who attempt to set traps in other areas are usually warned in one way or another. If they
refuse to stop their incursions, their traps are destroyed. Defending traditional lobstering
territories in this way is illegal, but it occurs constantly. Usually, only a few traps are
destroyed, but there have been occasions when lobster wars break out which result in enormous
property losses and a lot of bitterness. For this reason, people are apt to think of the
territorial system as destructive and even as a form of criminal activity.
There is a positive side to the system, however. In those areas where territories are defended
most vigorously and where it is most difficult to join harbor gangs, the amount of fishing
pressure on lobsters is reduced. Our research over the past 15 years shows that this leads to a
number of favorable results: lobster catches are larger; the lobsters in those areas are slightly
bigger; the catch per unit of effort is larger; and there is some evidence that the breeding stock
is greater in these areas.
If the territorial system is hard on interlopers, it is beneficial for lobster fishermen who are
permitted to fish in these areas. More importantly, it benefits conservation efforts and helps
ensure the lobster resource. What all this suggests is that limited entry works.
How do we in Maine take advantage of this situation? One way might be to formalize the existing
territorial system. Monhegan Island has long had its fishing area defended by the state, and
Swan's Island has recently established a trap limit in its waters. Could this be done effectively
along the rest of the coast without incurring tremendous enforcement costs?
Pilot Project in Canada:
Excerpted from the article A Pilot Project for Management of Lobster Stocks in Canada:
Would an Increase in minimum carapace length substantially increase the yield in Canadian lobster
fisheries? by Gerard Conan, A/Chief, Invertebrate Division, Canadian Dept. of Fisheries and Oceans,
Moncton, N.B.
Lobsters in the Gulf of St. Lawrence have traditionally been divided into "markets" and "canners."
Market lobsters have a carapace size greater than 3-3/16 inches and are intended for live sale,
while canners have a carapace size between 2-1/2 and 3-3/16 inches and are sold cooked, canned,
in coldpacks, or live in the local market.
The lobster fishery is regulated by minimum carapace size, prohibition to retain females with
eggs, limited number of licenses, maximum number of traps, trap size, and length of fishing
season. All of these regulations have helped maintain stable catches or increase them.
Theoretical "yield-per-recruit" models (which assume there is an increase in yield by one lobster
for every recruit) generally indicate that it would be beneficial to increase minimal legal size
in order to increase lobster yield and enhance egg production. In a yield-per-recruit model, the
concept is simple. If you leave the lobster in the water longer, it will grow and reproduce.
However, changing the fishery may induce other changes in the lobster population.
Data is not yet available to predict whether a greater number of lobsters, or a change in the age
structure will affect lobster fertility, growth, natural mortality, and hence recruitment. We also
do not know if the local environment can support more lobsters that all need shelters of
sufficient size.
We do know, however, that large lobsters tend to congregate in certain areas while small ones
prefer other areas. This may be a preliminary indication that the physical structure of the
environment may be limiting for certain size categories. It is also likely that mortality could
increase - especially during molt when adequate shelter is lacking for lobsters of a certain
size.
In many areas of the Gulf of St. Lawrence, canners make up as much as 80% of the catch. The
fishery is very dependent on recruitment to the canner size and, during the short fishing season,
most fishable lobsters are removed. As a result, any failure in recruitment could compromise a
full annual fishing season.
For our experiment, we increased the minimal legal carapace length of fishable lobsters from 2-1/2
to 2-3/4 inches in an isolated area where we had the cooperation of local fishermen. The coastline
region of Cape Breton Island, Nova Scotia, on the Gulf of St. Lawrence side was chosen as the
experimental zone.
Beginning in 1987, the minimum legal carapace size was increased by 1/16 inch per year. This will
continue until the target size of 3-5/16 inches is reached in 1990. Spreading the increase over
four years will offset a sudden decrease in landings, since canners make up a large proportion of
the catch. In addition, the use of escape gap mechanisms on traps has been mandatory since 1987 to
avoid fishery-induced mortality on short lobsters.
Short term effects of the project can already be assessed. There was a slight decrease in catch
for fishermen in the pilot zone in 1987, and a slight increase in 1988. It is difficult at this
time to differentiate these slight changes from previous year-to-year variability in landings, and
long-term results are not yet available.
The Canadian Department of Fisheries and Oceans has initiated three sampling projects within the
Cape Breton pilot zone to monitor the effects of the size increase. Following the 1988 lobstering
season, 5000 lobsters were tagged and released along the Cape Breton coast. From those lobsters
that return in future seasons, researchers will be able to analyze growth and movement during and
after the carapace size increase. They have also increased at-sea sampling to assess changes in
catch per unit effort and shift in size-frequency distribution, and to estimate any loss in
catches by fishermen.
The situation will be monitored closely over the next several years. Results of these experimental
studies could help determine whether an increase in the weight of individual lobsters actually
translates into an increase in the long-term number of lobsters available to the fishery.
The results of this experiment are also expected to have a great impact in other regions of the
Gulf. Fishermen are eagerly awaiting our input prior to forming their own opinion about whether
they should request federal government action to increase the minimal legal size of fishable
lobster in the Gulf of St. Lawrence.
(Editor's note: Fishermen in the Gulf of Maine are also eagerly awaiting the results of these studies.
The pilot project in the Cape Breton area should provide objective information on the response of lobster
populations to a management scheme involving an increase in legal minimum size - and that is of interest to all
of us.)
Industry Supports Lobster Cruise
Why has the lobster catch remained relatively stable over the last four decades even though the
number of traps has more than doubled? This has been a concern of fishermen, researchers and
fisheries managers for years. A ten-day lobster research cruise planned for this summer could help
solve the mystery.
Four marine researchers from the University of Maine - Bob Steneck, Dan Belknap, Les Watling, and
Rick Wahle - and Lew Incze of the Bigelow Laboratory for Ocean Sciences, will be invoved in the
project. Leaving from Boothbay Harbor on August 3, researchers will spend two days at each of four
sites in the Gulf of Maine. Sites include Head Harbor and Swan's Island in Maine; Isle of Shoals,
New Hampshire; and Nahant, Massachusetts.
Maine is thought to have the highest population density of lobsters per linear distance of
coastline in the world. Researchers will examine the hypothesis that bottom characteristics and
sediment types are important factors in determining the population densities of American lobsters
and other species that share their habitat.
The 80-foot R/V ARGO MAINE, the only U.S. deep-sea research vessel north of Cape Cod, will serve
as the mother ship for the cruise. Two other small University-owned boats, the R/V Lee and the
R/V Sculpin, will be used to conduct side scan sonar work (which produces a map of the ocean floor
resembling an aerial photograph), collect planktonic lobster larvae and invertebrate samples, and
transport divers. Lobstermen involved in the Lobster Institute have offered the use of their boats
to help transport media people from the land bases out to the ARGO and research sites.
The kinds of questions which will be addressed on the cruise could have far-reaching implications
for the industry. An important concern is whether the minimum size of legal lobsters should be
increased to conserve the industry. Another is whether lobster hatcheries are effective in
increasing lobster stocks, or are there already too many larvae in the ocean relative to the
amount of suitable habitat available? The answers to these, as well as other vital questions, will
be the focus of the cruise.
Biodegradable Escape Panels Tested in New Jersey
Excerpted from an article Marine Plastics: A Positive Perspective by Kim Kosko, New Jersey Marine
Sciences Consortium
Plastics have proven useful in many marine-related industries, because they are versatile and
practically indestructible. But durability is not always a desirable characteristic. Carelessly
discarded plastic products can pollute our oceans and threaten marine life indefinitely. The New
Jersey Marine Sciences Consortium, New Jersey Sea Grant, and Stevens Institute of Technology's
Polymer Processing Institute are currently collaborating on projects geared toward developing
plastics for the commercial fishing industry that are more efficient and environmentally sound.
The lobster trap industry has traditionally used very few synthetic materials. Traps are usually
made from treated wood or wire which may last a long time in the ocean and continue to capture
lobsters even after they are lost or abandoned. Lobsters trapped in lost pots may starve to death
or be eaten by other lobsters. With more than 200 thousand pots lost between Maine and Delaware
each year, a significant percentage of the commercially valuable lobster population could be lost
in these "ghost" traps.
One project initiated by the New Jersey Marine Sciences Consortium involves introducing and using
plastics in traps. Researchers are planning to replace some slats in a lobster pot with a
degradable plastic so creatures caught in lost pots have a better chance for escape and survival.
The project, funded by a $187,000 federal grant, involves several phases. The first one focuses on
developing biodegradable materials made from off-the-shelf products for the "escape panels" and
testing them in specific water temperatures and on different bottom types.
Dr. Ken Gonsalves of Stevens Polymer Institute produced specially designed biodegradable materials
from commercially available polymer products, and tested them in the ocean along the eastern and
gulf seaboard. Since lobstermen indicated they didn't want a product that had to be replaced more
than once every three to six months, Dr. Gonsalves is looking for a plastic that would last about three
months in salt water.
The second phase of the project involves developing and testing new biodegradable polymer
materials which could be used for traps. This phase will involve field testing in cooperation with
fishermen along the east coast.
After almost nine months on the project, Dr. Gonsalves has found that degradation (disintegration
of the degradable materials) depends to a great extent on the location, and that warmer waters
seem to enhance the process.
NH Researchers Study Lobster in Great Bay
Win Watson and Hunt Howell of the University of New Hampshire's Zoology Department have received a
development grant from the New Hamphire Sea Grant College Program to study lobsters in the Great
Bay Estuary. Ed Heaphy, a lobsterman in Great Bay, will be cooperating on the project. The Great
Bay system is located where the Piscataqua River, which separates Kittery and Portsmouth, meets
the Atlantic Ocean.
Although the American lobster is being studied extensively in saltwater marine environments,
little is known about lobster biology and behavior in estuarine habitats. Watson and Howell's
study will help determine how much lobsters use the estuary and whether they use it for breeding,
as a nursery, or feeding; what their distribution is spatially and at different times throughout
the year; and whether there is an estuarine population separate from the coastal population and
how much they mix. They will also examine seasonal movements, territoriality and homing behavior,
and how lobsters respond to changing conditions in the estuary.
An estuary is a semi-enclosed body of water where fresh water from rivers and tributaries mixes
with incoming tidal salt water from the ocean. This causes wide fluctuations in the temperature
and salinity of estuarine water. Therefore, lobsters living in this environment must cope with
drastic and often sudden changes in both the water temperature and salinity. This is especially
true in the spring when freshwater run-off and frequent storms dramatically lower the water's
salinity. Watson and Howell will investigate what impact these changing conditions have on lobster
populations.
The results of this sudy could have far-reaching implications for fisheries management plans. If,
for example, lobsters in New England estuaries don't mix with those in coastal waters, then
populations from these different areas must be managed separately. On the other hand, if there is
extensive mixing, then events that occur in one area will affect the other. In addition,
information on the distribution of lobsters is needed to access the impact of shoreline
development, dredge and fill operations, marina development, and the leasing of areas for
aquaculture.
For more information, contact Win Watson, (603) 862-1629 or Hunt Howell, (603) 862-2109.
Lobster Tests:
Red tail or gaffkemia is a serious threat to lobsters held in pounds or cars because the disease
spreads rapidly and can cause high mortalities. As infected lobsters die, they release millions of
bacterial cells into the water which can then infect other lobsters. Even one bacterium, entering
a healthy lobster's body through the smallest break in the shell or soft tissue, can infect the
lobster with the disease. Also, the warmer the water, the more quickly the bacteria will spread
and the sooner it will kill its host.
Herb Hodgkins of Lobster Products in Hancock has been working with researchers at the University
of Maine for the past 14 years to devise a test to detect gaffkemia in its early stages, and
develop a method to control it. A medicated lobster feed containing an antibiotic resulted from
this research.
Four years ago, Hodgkins started a business to help pound owners diagnose gaffkemia and determine
when treatment is needed. He routinely travels to pounds in Maine and Canada with his test kit to
sample lobster blood. He has also marketed the pelletized medicated diet, as well as other diets,
to pound owners throughout the region.
Kathleen Anderson, a student at the University of Maine, has found that a commercial test used for
detecting antibiotic residues in milk from dairy cows is also effective when used with lobster
blood. The Delvotest P takes only 2-1/2 hours to complete, is simple to use, and accurate. The
test kit can be purchased from Gist Brocades, P.O. Box 241068, Charlotte, NC 28224. For
information or a demonstration on how to use the test, contact Herb Hodgkins, (207) 422-6238.
In the limited entry debate that has been going on in the lobster industry for the past
twenty years, it is important to recall that the lobster industry already has a form of limited entry.
As anyone connected with the industry knows, only certain people are allowed to go fishing from each
harbor in Maine, and that members of these harbor "gangs" are only allowed to go fishing in the
traditional territory of that harbor.
Will Increase in Gauge Increase Yield?
Simple and Effective
The medicated diet contains the antibiotic Terramycin (Oxytetracycline) which has proven effective
in both controlling and, in many cases, preventing or curing gaffkemia. Before lobsters can be
marketed, pound owners must be sure that no antibiotic residues remain in the edible tissues of
the lobster. A conventional residue test has been used to ensure that lobsters are free of
antibiotics. However, this test is very time-consuming, expensive, and requires laboratory
supplies that are difficult for the average lobster dealer or pound owner to obtain.