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What is Overfishing?
The portion of the American lobster resource that resides in the EEZ
(Exclusive Economic Zone: 3 to 200 miles offshore) is considered to be overfished
when it is:
1. harvested at a fishing mortality rate and minimum size combination that
results in a calculated egg production per recruit of less than 10% of a
non-fished population, or;
2. harvested at a fishing mortality rate and minimum size combination that is
not consistent with a program that has been developed to rebuild the stock.
Increased landings and survey results indicate a pulse of recruits are moving
into the fishery. This increase in recruitment is due, in part, to favorable
environmental conditions. Based on this, the current calculations indicate that
egg production per recruit is at about 3 to 5% of maximum. While the population
seems to be relatively stable, this is most likely not an acceptable long-term
level. When environmental conditions change, it is more likely that a higher
level of egg production will be necessary to prevent recruitment decline or
failure. Therefore, the 10% level should be viewed as a target during this period
of abundance, and a long-term goal of the management program.
This definition is applicable across the entire American lobster resource.
Because so much of this resource resides in state waters, however, a more
appropriate long-term approach assessing overfishing of this resource would
involve a uniform research effort which integrates state and offshore management,
data collection, and analysis."
Excerpts from a response by Dick Allen, Vice President, Atlantic Offshore
Fishermen's Association
While the Magnuson Act and our fisheries management experiece have made it
clear that optimum yield includes factors other than "biological" considerations,
an approach that emphasizes optimum yield does not ignore measurable indicators
of the health of the resource, as well as the health of the fishery. Such an
approach would necessarily include a subset of biological indicators.
While we should seek the greatest possible objectivity and measurability in
our indicators, prediction should be based upon a risk assessment approach. If we
assume that optimum yield, or greatest overall benefits to the nation, and
overfishing are separated by some middle ground, management should be able to
respond to an early warning risk assessment in a way that keeps the fishery
operating closer to the optimum yield area than the overfishing area.
In summary, this Amendment satisfies the requirements of the "602 guidelines"
in the following way:
1. Management is focused toward achieving measurable indicators of optimum
yield.
2. A subset of the optimum yield indicators provides an early warning risk
assessment of the likelihood of overfishing developing. This assessment is
carried out in the following manner:
A. These indicators are tracked:
1. Landings
2. Size composition of the landings or the stock from sea sampling (Is there
a range of age classes on the grounds, or are they all being caught in the year
that they shed into the legal size?)
3. Spawning stock biomass (How big is the total population?)
4. Number of egg-bearing females
5. Larval abundance index (Sample surface waters for lobster larvae each
year)
6. Larval settlement index (Sample larval settlement habitat each year to
determine the success of the new year class in reaching the bottom)
7. Pre-recruit indices by year-class (How many sub-legals of various sizes
are present on the grounds?)
8. Effort levels (How many traps or trap hauls?)
9. Catch per unit effort (Is the catch per trap increasing or decreasing?)
10. Water temperature (Can water temperature be shown to have a predictive
value for spawning success, growth, etc.?)
B. Each indicator could be assigned a score, based upon its trend over a period
of years, and the implication of that trend for the fishery. A sum of the scores
would indicate the relative degree of risk that the fishery is trending toward
overfishing. Various corrective measures could be triggered, depending upon the
overall score and the nature of the problem.
While the discussion above is directed at meeting the requirement for a
definition of overfishing, this approach to management has the additional benefit
of providing objective criteria that can be used to respond to industry and
public concerns about the management system. It is unlikely that any fishery
management system will satisfy all interested parties all of the time. Without
measurable, objective criteria that can be used to evaluate the overall health of
the fishery, the management system will find it difficult to respond to
criticism, and to avoid being buffeted by the emotional issue of the day.
The full set of indicators of the health of the fishery, therefore, must be
broader than the biological indicators alone. Such things as price, revenue,
costs and earnings, capitalization, producers' surplus, consumers' surplus, net
social surplus, and other factors could be tracked and scored to provide an
overall assessment of the health of the fishery in both biological and economic
terms. Unless we agree upon a definition of successful management, we will never
know when we have it.
Loyall Sewall, Maine Import/Export Lobster Dealers Assn. Statement before Scoping
meeting for Development of a Comprehensive Amendment to the Fishery Management
Plan (FMP) for American Lobster
We are all here for the purpose of protecting the lobster resource and
industry. You are also faced with a definition of overfishing. The adoption of
this definition frankly scares me. While I realize it is based on conservative
available scientific knowledge, I also realize, and I think everyone will admit,
it is based on insufficient scientific knowledge to guarantee it's infallibility.
If it is correct, then everything is fine, but if it is in error, it could either
ruin the resource or ruin the industry. Either of these results are exactly what
we are trying to avoid.
I would, therefore, suggest that the definition of overfishing be based not
on one factor but on a series of indicators which will give us on a continuing
basis, not just the current or hypothetical, but the actual future health of the
resource and industry.
Using these indicators, an acceptable level could be established and when the
indicators fall below those levels, an alarm bell would go off which would
require the institution of remedial measures. At this point, a remedial measure
appropriate to the danger would be instituted and the indicators would show
whether or not they are working.
At this particular time the lobster resource, for reasons unknown, is in
pretty good shape. We therefore have the luxury of basing our indicators on a
healthy rather than an endangered resource. The reasoning behind this concept is
flexibility and utilization of contemporary warning signs.
If favorable environmental conditions, as the proposed definition indicates,
have resulted in the current increase in recruitments, indicators will show when
these conditions change, and the alarm bell will tell us that something must be done
and how drastic that must be. We may not have to go after the mosquito with a
sledge hammer. I believe that it is unwise and perhaps reckless to gamble the
entire future of the resource and industry on "guestimates" of what's going on
and what's caused it, no matter how sincere they might be.
I. Conservation
We must look at the health of the resource 5 to 7 years into the future. How
can this be done? I propose a continuous monitoring of indicators which provide
not only the current status but the status of the recruitments. These should be
not one, but a series of factors (like a cost of living index) which provide us
with the information not only of the state of the resource, but the state of the
future. I'd propose monitoring factors such as:
When lobstermen convinced the New England Fishery Management Council (NEFMC) to
recommend to the U.S. Secretary of Commerce that lobster size increases for 1991 and 1992 be delayed, the
tradeoff was that the Council must write an entirely new lobster management plan by next March.
One of the most important parts of this federal lobster plan is the definition of overfishing. To know
whether lobsters are being overfished, we first have to know what overfishing is. This has been a controversial
issue for years but one that is crucial to the future health of the resource and industry.
Following is the proposed definition of overfishing for American
lobster developed by the National Marine Fisheries Service in January, 1991,
and some responses to it by members of the industry and the science community.
We shouldn't be concerned about definitions of overfishing based on
assumptions and data which admittedly are based on insufficient information. The
proposed definition of overfishing looks only to egg production and harvesting -
it gives no consideration to other factors such as climate, disease, predators or
disasters such as an oil spill, which could equally affect the health of the
resource. The resource is what we should be concerned about - not just the egg
production.
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* Landings * Sea studies * Levels of effort * Reports from fishermen and observers, etc. * Natural and unnatural impact * Critter counter through trawls or other means * Any others |
These could be monitored on a regular basis in order to give us trends or indicators to allow for remedial actions.
II. Economics
The resource without the viability of economic survival of the fisherman,
dealers, etc. must also be considered, so economics must be considered. The
single most important factor to this is the uniformity of the gauges. All states,
and hopefully Canada, must have a uniform gauge to make everything work.
Different gauges in different areas disrupt the market so that no one has the
ability to economically survive, or creates a dog-eat-dog scenario with different
states establishing gauges to gain advantage over others to the detriment of the
resource as a whole. Therefore, economic factors must be cranked into the
indicators such as:
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* X-boat price * Market demand * Earning levels * Landing values * Other economic indicators |
III. Workability and Enforceability
Any plan, to be effective, must be workable and enforceable. Therefore, as
far as possible, traditional practices and readily available data should be
utilized.
Proposal for Management Plan
1. Divide the offshore from inshore fishery:
A line could be drawn delineating the Boundary between the trip-boat and the day-boat fishery. The reasoning behind this is that management proposals between the two could differ substantially.
2. Extend the state management plans out to the offshore line:
The reasoning behind this is that fishermen are accustomed to working with state lines and most boats reaching the offshore line will have Loran. (It's important that the line be drawn along Loran bearing.) I realize in some cases the state lines between the three-mile limit and the offshore line may conflict but that could be worked out between the states.
3. Establish a committee to oversee the management of each zone. This will provide for each zone, whether it be a single state or a number of states, the authority to recommend to the Regional Director of Marine Fisheries that implementation of a remedial management plan go into effect.
4. Remedial measures would go into effect if indicators show that the stock in any zone is heading for trouble.
There are many acknowledged remedial methods that might be used to prevent an over-utilization of the resource such as:
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* Trap limits * Limited entry * Quotas * Seasons * Limiting men per boat * Limiting the hours of effort * Gear modification, i.e. vents, etc. |
Jim King, President, Long Island Sound Lobstermen's Association
I recently received the summary minutes for the February 14 meeting of the Lobster Plan Development Task Force and would like to convey some thoughts and ideas to you.
We are happy to see that regional distinctions in the resource are recognized and considered to be important. The lobster fishery in Long Island Sound reaches from the heavily populated urban areas of New York City to the rural farmlands of easternmost Long Island, as well as the state of Connecticut. We, therefore, see many differences in fishing methods, conditions and social attitudes. Since we also share a common resource with Connecticut and have reciprocal license privileges, there is steady interaction between both state's lobstermen. Uniformity between both state's lobster laws is important. I would suggest that Long Island Sound be considered as a definite lobster management sub-area with a bi-state lobster management advisory panel of qualified, credible industry leaders.
A definition of overfishing that would apply to the overall range of the lobster resource is impossible. There are simply too many variables and differences in stock structures. I have watched the average size of our Sound lobster decrease, but increase in population. 75-80 mm egg-bearing females are commonplace.
Based on mortality rates as an indicator, our Sound lobster fishery should have collapsed years ago. These unique animals seem to be highly adaptable to stressful conditions and heavy fishing pressure. Strong enforcement of our lobster conservation laws, protection of juveniles and egg-bearing females, is paramount if we are to be successful in managing this resource. There is no longer any room for the irresponsible in our fishery. Heavy fines and license suspensions or revocations for the more serious conservation law violations must be applied to those that choose to ignore the rules.
I have been a full-time lobsterman in the Sound since 1964 and have watched this fishery grow from a small, primarily part-time fishery into a year-round occupation and the most valuable single species resource in Long Island Sound. I have observed far too many changes in this time period to write about at this time. All I can say is that the resource appears to be in excellent health, despite the heavy fishing pressure upon it and the many water quality problems.
I personally feel the time has come for a limitation on the fishing effort but we must proceed cautiously and sensibly to ensure success for the future. To be quite frank, the lobstermen themselves are the real managers of this fishery. We are the ones in direct physical contact with the resource and its future lies in our hands, not in those of the bureaucrats.
Another subject that must be addressed, particularly in the inshore areas, is pollution abatement. A healthy lobster resource will be worthless if contaminated by heavy metals, PCB's, or other harmful substances.
I look forward to working closely with you and the other members of this Task Force. Lobstering for me has not only been a source of income, but a way of life that I cherish and am willing to fight for.
Robert S. Steneck, Associate Professor of Oceanography, University of Maine
If managers chose to take a scientific approach to lobster management, it seems to me the following points are relevant to determining when and if lobster stocks are overfished.
The urgency of all overfishing discussion to date has been to avoid a population collapse. Thus this question has been defined as a biological one and should be pursued as such.
The National Marine Fisheries Service's two definitions for overfishing of the American lobster require that we know "Fishing mortality rate (F)." For this, it is essential to know the total population size of lobsters in the domain of interest. I do not believe that is known. Trap-caught lobsters cannot adequately census lobster stocks with any degree of precision because of variations in trapability (see Miller 1989, 1990 for full discussion of this problem). Catch per unit effort may bear no resemblance to the population density in a given region. Also, knowledge of total population demography would be necessary to determine what is required to "rebuild...stocks." That is, rebuild assumes one knows to what level.
Do we know that the assumptions are correct? For example, in the narrative following the two definitions, the statement is made: "This increase in recruitment is due, in part, to favorable environmental conditions." I suspect that may be true, but I know of no data to support it. However, the narrative continues: "Based on this, the current calculations indicate that egg production per recruit is at about 3 to 5% of maximum." That statement is based on the assumption of unspecified environmental control of recruitment and further assumes knowledge of some maximum egg production (again requiring knowledge of the entire population size).
The conclusion is then reached that "when environmental conditions change, it is more likely that a higher level of egg production will be necessary to prevent recruitment decline or failure." There is no support for this based on recently published, peer-reviewed literature (e.g. Wahle and Steneck,1991). Although unspecified environmental conditions may or may not affect larval recruitment success, a deleterious change in those conditions does not necessarily translate to a reduction in or failure of larval recruitment.
The 45-year stability in lobster catch argues strongly against strong environmental control in lobster recruitment. To speculate otherwise implies that we have had 45 years of environmental stability (a point which would receive little support from most marine scientists). Current literature suggests that although the recent increase is not well understood, stasis in lobster landings is probably due to limited nursery grounds (Wahle and Steneck 1991).
There is reason to question mortality estimates. Most are based on size-frequency analyses of trap-caught lobsters. This approach is undermined by observations of Karnofsky and Price (1989) and others who suggest that as high as 40% of the harvestable lobsters may never go in traps.
Size-frequency techniques are also sensitive to even short-distance migrations if lobsters leave a region where they are likely to be trapped. Similar concern over the accuracy of mortality estimates would be raised for mark and recapture studies involving trap-caught lobsters. Standardized trawl surveys have also been shown to be inaccurate. Uzmann et al (1977) compared in situ and trawl sampling techniques and concluded that trawl data is highly suspect and represented no more than 1/3 of the observed lobster population density.
Trawl efficiency varies greatly depending upon bottom type. I have observed, with equal trawl effort, high lobster catches on featureless bottoms and low catches on complex boulder-strewn bottoms, although in situ censuses yield opposite population densities. The problem is that if an important determination relies on a single estimate (e.g. Fishing Mortality "F"), then the veracity of that estimate should be impeccable.
I submit that if this proposed definition of overfishing were to be considered with the level of rigor applied to NSF proposals, it would not fare well. Although the information sought is laudable, the essential elements lack an empirical base. Without such a foundation, this definition cannot be realistically applied today.
An Alternate Perspective
A simpler definition of overfishing should be based on demographic parameters
directly. This is analogous to methods used for fish and game. Lobsters are among
the easiest marine organisms to census. Direct measures of numbers per unit area
avoid all the trap-related questions raised by others (e.g., Miller 1990).
The question should be, is there a significant decline in harvestable lobster densities (i.e. number per unit area), reproductive phase lobsters, lobster larvae, or newly settled lobsters on the benthos? A new definition would require an agreement as to what a "significant" decline is, but this would not be difficult.
This approach has the advantage that it is based on quantifiable and repeatable data and involves techniques used in peer-reviewed publications. The data are very easy to generate and an empirical base already exists. It does not involve a chain of assumptions for which data are absent or equivocal. The specific data needed to monitor for overfishing would include:
a) Direct counting of early benthic phase lobsters in nursery grounds. This would be the simplest and most cost-effective parameter to measure to determine if the populations are going to decline for any reason (i.e. from overfishing, disease, pollution or whatever).
b) Direct counting of adolescent phase lobsters (including just harvestable sizes). This would be another cost effective way to track population densities.
c) Direct counting of reproductive phase lobsters. This is more difficult because they predominate in deeper water but recent work with submersibles has been promising. Constant monitoring of V-notch lobsters would be another means of assessing the stability of reproductive phase lobsters.
d) Direct counting of larval lobsters is least conclusive for reasons identified by Fogarty and Idoine (1986) but obviously a complete larval failure from a catastrophic pollution spill, for example, would be disastrous to lobster stocks, although it would have nothing to do with overfishing.
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As of May 16,1991, the NEFMC revised the definition of overfishing to read: The American lobster resource is
considered to be overfished when based on information concerning the status of the resource throughout its range,
it is harvested at a fishing mortality rate (F) and minimum size combination that results in a calculated egg
production per recruit of less than 10% of a non-fished population. The Council voted to put on hold a description of the current status of the lobster resource compared to the 10% threshold, until the overfishing working group completes a comprehensive evaluation of the whole lobster resource. A rebuilding program and schedule was also put on hold. |
Do Lobster Hatcheries Really Work?
Since 1986, thousands of hatchery-reared lobsters have been released along
the coast of Maine to enhance existing stocks. However, the question remains
whether lobsters raised in hatcheries survive after they are released into the
wild. Since there has been no way to measure the survival rate of hatchery
lobsters, many doubts have been raised about the feasibility of hatch-and-release
programs. Two research projects at the University of Maine are providing
information to help determine whether hatcheries work.
In 1888, researchers started using blue lobsters (which occur naturally in
one out of every 3 to 4 million adults) as natural tags for tracking
hatchery-reared lobsters. If hatchery blues start showing up in traps in sizeable
numbers in a few years, it would suggest that hatch-and release programs could
have a positive effect on the fishery. However, questions about the behavior of
blue lobsters and their survival rate still need to be answered.
Chris Irvine, graduate student in the University's Department of Animal,
Veterinary, and Aquatic Sciences, is examining whether blue lobsters have
behavior patterns which differ from those of normal ones. In a laboratory
setting, Irvine analyzed four basic behaviors - swimming, burrowing, walking, and
lack of activity - on six different substrates. These bottom types included mud,
sand, eelgrass over mud, eelgrass over sand, pebble over sand, and cobble over
sand.
Sam Chapman, Aquaculture Specialist at the University's Darling Marine Center
in Walpole, provided the lobsters for the study. All lobsters tested had carapace
lengths of approximately 4, 5, and 6 millimeters (about 1/4 inch) and were in the
postlarval stage, when lobsters can still swim but are soon capable of settling
on the bottom.
With a video camcorder, Irvine recorded blue and normal lobster behavior on
the different substrates. After conducting 82 trials (47 with blue lobsters and
35 with the normal "control" lobsters), Irvine concluded that there was no
significant difference between the behavior of blue and normal lobsters.
However, the study showed that in a laboratory setting, smaller lobsters (4 to
4.9 mm CL) swim more than larger ones, and they swim more often over sand and
least often over cobble. Conversely, larger lobsters (6 to 6.8 mm CL) burrow more
than smaller ones, mainly in the eelgrass over mud substrate. Finally, smaller
lobsters walk more and spend the least amount of time in lack of activity. A
possible explanation is that lobsters in the first postlarval stage, when they
are smaller, use their energy searching for appropriate habitat.
Bob Steneck, professor of oceanography and marine studies, is looking at the
survival of hatchery-reared lobsters in the field. Last summer, Steneck and a
team of student interns released thousands of early benthic phase (EBP; 5 to 40
mm or 1/5 to 1-1/2 inch CL) lobsters in research locations near Placentia, Great
Gott, Long, and Little Cranberry Islands in Blue Hill and Frenchman Bay, Maine.
Sites chosen had ideal cobble habitat but no EBP lobsters.
According to Steneck, these areas have plenty of food for lobsters to eat, as
well as adequate water temperatures and salinity. However, the catch is 10 times
below what could be expected. With funding from the Maine Aquaculture Innovation
Center and the Lobster Institute, Steneck is introducing EBP lobsters to these
underpopulated areas to see if a native population can be established.
A day after lobsters were released, researchers resampled the experimental
sites and found that 75 percent of the sites had newly released EBP lobsters.
This summer, Steneck will survey the same area to find out how many
hatchery-reared lobsters survived and their growth rate. He is also planning to
conduct controlled releases of blue lobsters to determine their survival rate and
discover whether there are significant differences between blue and wild lobsters
in the field.
Hopefully, results from these studies will help clarify whether hatch and
release programs are worthwhile. Although lobster landings hit an all-time record
last year, the catch in the northern Gulf of Maine, where Steneck is conducting
his studies, remained low. According to Steneck, "A focused enhancement effort
could significantly increase local lobster landings. If these guys could catch 10
times as many lobsters, I'm sure they would be very happy."
Tracking Down the Cause of Shell Disease
Deanna Prince, graduate student in the University of Maine's Department of
Animal, Veterinary, and Aquatic Sciences, has isolated several types of bacteria
that appear on the shells of healthy and diseased lobsters. Working with Wayne
Banks of Shag Harbor Lobster in Nova Scotia and Herb Hodgkins of Seal Point
Seafoods in Hancock, Maine, Prince obtained bacterial cultures last December
which she will analyze in the laboratory this summer.
With funding from the Maine Lobster Pound Association, Prince will identify
those bacteria that break down chitin, one of the major components of lobster
shells. These shell-degrading bacteria could be the cause of shell disease.
As Prince explains, "The ultimate goal of my research is to find a cure for
the disease. At this point, I think the most effective and fastest treatment may
be an antibiotic or disinfecting iodine dip."
Profile:
"I retired from lobstering when I was 47. I was having a new boat built for
a yacht and it just drove me crazy. I had the builder change it over to a lobster
boat and I got back into business again." Now in the midst of building Super
Nova, his 14th boat, Basil Heanssler of Conary Cove Lobster Company is still very
much in the lobster business.
Like many young men in Maine born with lobstering in their blood, Basil began
fishing at a very early age. At seven years old, he was hauling his own traps
from a rowboat. For many years, Basil not only fished, but picked up lobsters for
his father's pound. When his father bought lobsters, Basil noticed that "these
Swan's Island fellows who were offshore were coming in with real big catches. I
figured If they could do it, I could do it. So I went way down the bay, and ran
more traps than the fellows around here and I was the first one to fish winters
out of here." Following in his father and grandfather's footsteps, Basil worked
hard to get what he wanted.
When Basil was twenty, he built his first boat. "When I got married, I had a
new boat and a new home and I was only 900 dollars in debt." When asked how he
met his wife Harriet, Basil answered, "I met her here and took her smelting to
see if she was a good fisherman and she was. That was quite an easy way to get
acquainted in the old days. There was always a pile of smelts around every spring
because everyone was out smelting."
In 1972, Basil took over his father's pound. According to Basil, "I really
love lobstering, but of course when you get older, you can't keep up. I loved the
competition but I didn't want to get beat. So, it's a good thing I'm not fishing
now!"
Born and raised in Sunshine, Maine, where 80% of the people are his
relatives, Basil has left the island to live elsewhere only a few times. One was
when he joined the Coast Guard in 1941. For his shore patrol training at
Manhatten Beach in New York, Rocky Graciano was the head of physical training for
his platoon. "Whenever I was boxing with him, I wasn't doing something right. My
arms were too shortÑI was always getting hit."
Basil built his own pound, with a capacity of about 200,000 lobsters, in
1979. Two of his sons, Nelson and Chuck, work for the pound full-time while
Harriet, his daughter Kathy, and 15 year-old grandson Jason work there part-time.
His oldest son David is a year-round fisherman who occasionally helps out when
needed.
Thinking back to the days in his father's pound, Basil remembers, "Years ago
they didn't have enough research into the diseases of lobster, like gaffkemia.
I've seen my father go in and drain the pound and scoop lobsters up by the
dory-load and lug them out. Nowadays, with the research from the University, they
know what's wrong. The first year when we tried the medicated feed, this pound
only had a 3/4 of a percent shrinkage. It's really helped us a lot."
When asked what he enjoys doing most, Basil immediately answered "working."
He's the first one at the pound everyday and, most days in the summer and fall,
works from dawn to dusk unloading lobsters from his dozen or so boats. However,
he does manage to find time to paddle a canoe around the harbor with Harriet or
go for a picnic on one of the islands. When his newest 45-foot boat Super Nova is
finished, he and Harriet plan to take many trips to Nova Scotia - one of their
favorite places to visit.
According to Basil, "I intended to be a sailor when I went in the Coast
Guard, but I think I've had a better life being ashore. I look around and see
fellows my age who became captains, and it looks to me as if their lives have
been pretty empty. I have a good family and that really means a lot to me." As to
living in Sunshine, Basil says "I wouldn't want to live anywhere else. There are
about 900 acres here and 120 year-round residents, so it's not crowded. I like
people, but when they go to bed at night, it's nice to have things quiet."
Basil Heanssler:
The Man Who Always Has a Boat Coming Along Somewhere