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     DEPARTMENT OF MARINE RESOURCES

 
COASTAL FISHERY RESEARCH PRIORITIES 

 AMERICAN LOBSTER 

(Homarus americanus) 

Forward
Executive Summary

Prepared by the
Gulf of Maine Aquarium
January 10, 2001  


Table of Contents   


 

   

Acknowledgements 

Our thanks to the many people who have made this project happen.  It would not have been undertaken without the commitment and vision of Linda Mercer, Director of the Bureau of Resource Management at the Maine Department of Marine Resources (DMR).  Her participation at every step of the way is an integral part of the final product.  Particular thanks go for her careful editing of the document.  Sue Inches, Director of Industry Development at DMR saw the opportunity to get funding and has provided support throughout.  Paul Anderson, Director of the Maine Sea Grant Marine Extension Program (MSGMEP), provided funding and his planning skills, took excellent notes, and generously contributed his staff.  The staff of DMR and MSGMEP helped in the planning and in making both the substance and the details of the meetings work.  Finally, without the fishermen and scientists who attended the meetings, this project would not have gone forward nor produced worthwhile results.  

Robin Alden
Don Perkins
Gulf of Maine Aquarium

 

 

MAINE DEPARTMENT OF MARINE RESOURCES

 COASTAL FISHERY RESEARCH PRIORITIES

AMERICAN LOBSTER (Homarus americanus) 

 

I.  Background  

The American lobster (Homarus americanus) fishery is Maine's signature fishery.  It dwarfs all other fisheries in numbers of participants and value to the state.  In 1999 the dockside value of the catch was a record $185 million, with an estimated economic impact on the state economy of $500 million.  There were 5930 commercial lobster/crab licenses in 1999.  Of those, 3,457 are estimated to be full time and 2,000 are estimated to be part time. 

Lobster abundance, landings and value have steadily increased since the late 1980s.  Prior to that, the long-term average landings had been in the 20 million-pound range.  Landings topped 40 million pounds in 1994 and were 53.5 million pounds in 1999.  In this respect, it is recognized worldwide as one of the few fishery management success stories.  Nonetheless, the federal government includes lobster on its list of overfished species based on the estimates of fishing mortality rate from the lobster stock assessment.  The discontinuity between this long-term increase in landings and concerns about overfishing during the last 10-15 years has resulted in research into some of the basic dynamics of the lobster population. 

The role of lobstering in the Maine fishery has changed during the last 20 years.  Never before has lobstering so dominated the fishing economy of Maine.  This has taken place through a combination of lobster abundance and various changes in technology that drew effort into the fishery.  It has been exacerbated by a simultaneous loss of opportunities for Maine fishermen in other fisheries such as groundfish and scallops as a result of federal management plans.  The result is a change in Maine's coastal fishery from one that shifted between various inshore fisheries seasonally and year to year, to a virtually single species fishery and a dependence on lobstering that is unprecedented in Maine fishing history.  

Lobster management occurs at a number of levels.  Maine regulates the fishery through both legislative action and Department of Marine Resource regulatory action.  The state participates in interstate management through the Atlantic States Marine Fisheries Service (ASMFC).  ASMFC decisions must be implemented in Maine through state action; however ASMFC has the power to declare a moratorium on lobster fishing in the state if Maine does not comply.  The National Marine Fisheries Service regulates the lobster fishery in federal waters, in concert with ASMFC policy, but through federal rulemaking.  Finally, instate, Maine has delegated some authority directly to the lobster industry, which is one of the most significant examples of co-management in the country.  

The state is divided into seven lobster management zones, each of which is divided into voting districts of approximately 100 fishermen.  Lobstermen elect representatives to a council that can set referendum questions.  Zones can decide by referendum vote the number of lobster traps below the state cap, the number of traps on a trawl, and the time of fishing.  

Entry to the lobster fishery is controlled through a two-year, on-board apprenticeship requirement.  In addition, lobster zones have now been given the power to limit entry in the zone through an entry/exit ratio.  One member from each zone council sits on the statewide Lobster Advisory Council. 

Maine lobster regulations protect both juveniles and large lobsters through a dual gauge that includes a 3 1/4" minimum measure and a 5" maximum measure.  Lobstermen may voluntarily cut a v-notch in the tail flipper of an egged-out female to mark it.  That lobster is not legal to catch until the notch disappears through successive sheds, usually after several years.  

Lobster fishing in Maine State waters and by Maine license holders is restricted to traps.    Maine lobster traps are required to have a vent to release undersize lobsters. Trap dimensions are also regulated.  The state has a statewide trap cap of 800 traps per boat.  One zone has imposed a lower trap limit of 600.  

The 1995 imposition of controlled entry, the trap limit, and the creation of the zone management system may have been the largest single change in lobster management in history.  Each year since then, further changes have been made in an effort to fine-tune the new system.  

The change to co-management with the lobster management zones is starting to create a demand for local scale research, at least at the scale of the seven zones.  The lobstermen are now responsible for certain management decisions and they are starting to generate research questions for their local area and to seek monitoring, such as settlement test sites, in their zones.  There is potentially interest and energy in the zones for collaborative information collection and monitoring.     

   

II.  The DMR Research Priorities Project

These lobster research priorities were developed as part of a larger research agenda-setting effort conducted by the Maine Department of Marine Resources (DMR) for five of Maine's major commercial species:  clams, lobsters, scallops, sea urchins, and shrimp.  

Establishment of research priorities was identified during the late 1990’s as a key strategy to accomplish several of DMR's agency goals as well as the King Administration's 1996 Jobs from the Sea Initiative.  The ultimate purpose of the DMR research priority project is to ensure that fishery management decisions are based upon the best scientific and technical information so that Maine's marine resources are sustainable and productive.  

The articulation of an agenda, however, will accomplish several other goals.  First, by establishing and communicating a shared vision of comprehensive research needs, it will stimulate the market for fishery research that serves the state's needs.  Second, DMR will be able to direct internal funding decisions appropriately and identify and involve potential research partners from the broader marine science community, including the fisheries and aquaculture industries.  Third, the agenda should enable the entire marine science community to develop quick responses to outside funding opportunities on topics that serve the state's needs. 

The project was conducted under contract by the Gulf of Maine Aquarium (GMA).  It was funded by a planning grant from the Economic Development Administration, the DMR, and the University of Maine Sea Grant Program.  The project was staffed by the GMA consultants, DMR and the University of Maine Marine Extension Team.  

   

III.  Methodology

At least one, all-day meeting was held for each fishery.  The meetings were designed to be non-regulatory, neutral, and inclusive following a format developed by the GMA in previous efforts for other species. The meetings brought together fishermen, academic scientists, government scientists, non-governmental organizations, and fishery managers as equals.   They created an open environment for curiosity and questioning.  Seven meetings were held on five fisheries to achieve broad input along the coast.  

Four topics were chosen for each species and scientists were invited to make short presentations on each of the topics.  Each of the presenters was asked to write a short analysis on some aspect of the topic or his/her research questions for the final report. 

Meetings ran from 9 a.m. to 5 p.m. with breaks and lunch provided.  Each day was divided into four sessions, each on a specific topic pertinent to the species.  The format of the sessions was the same.  First, the group spent ten or fifteen minutes brainstorming the questions they had about the resource.  Then the invited presenter gave a short presentation on a selected topic and on his or her major research questions about the species.  The group then discussed the topic and the presentation, generating a list of questions that were summarized by one of the facilitators for later ranking.  At the end of the day, one half hour was spent in an informal ranking process where everyone was given 10 sticky notes to stick by the topics of their choice.  The day wrapped up with an oral evaluation and discussion of follow-up and ways to improve the process.

Publicity for the meetings was customized for each fishery.  Methods included direct mail to license holders, personal contact with association leaders, and posters distributed to sites in each town.  All of the meetings were covered in press releases to local and statewide papers.  

   

IV.  Lobster Research Priority Meetings

Two lobster meetings were held:  April 25, 2000 at the Samoset Resort in Rockport, and April 27, 2000 at the White Birches in Ellsworth.  Both meetings were held from 9 a.m. to 5 p.m.  Topics and presenters included:

April 25:  

1.  Oceanography                Dr. Lew Incze, Bigelow Laboratory   
2.  Spawning/ Life History     Dr. Rick Wahle, Bigelow Laboratory  
3.  Assessment                   Carl Wilson, Department of Marine Rescues  
4.  Socio-economics            Dr. James A. Wilson, School of Marine Sciences, University of Maine  

April 27:  

1.  Oceanography               Dr. Lew Incze, Bigelow Laboratory 
2.  Spawning/ Life History    Dr. Rick Wahle, Bigelow Laboratory
3.  Assessment                   Dr. Paul Rago, Northeast Fisheries Science Center 
4.  Socio-economics            Dr. James A. Wilson, School of Marine Sciences, University of Maine 

Thirty people attended the April 25 meeting at the Samoset Resort and 36 people attended the April 27 meeting at the White Birches in Ellsworth.  Attendees included lobstermen, lobster dealers, representatives of Maine Lobstermen's Association, Downeast Lobstermen's Association, Maine Import Export Lobster Dealers Association, and Stonington Fisheries Alliance, DMR managers and biologists, and researchers from the University of Maine, Bigelow Laboratory and Northeast Fisheries Science Center. 

   

V.  Lobster Report Format

Results of the meetings are presented in two different formats: 
        1)      The priorities voted by the group (Section VI) which are presented with context; and
        2)      A detailed, categorized listing of questions, observations, and opinions articulated during the discussion (Section VII). 

The dual format is necessary in order to capture the richness of the meetings.  The priorities organize thought and focus effort.  The details are essential because it is the local observations and questions that provide the raw material of good scientific hypothesis.  Although the lobster meetings were divided into four segments:  Oceanography, Spawning/Life History, Assessment, and Socio-economics, the report is not structured around those categories except where it makes sense.  Many topics, such as oceanography, growth and reproduction were raised in several of the segments.  Therefore we have given precedence to the priorities articulated at the meeting rather than those used to organize the meeting.  Furthermore, we have not attempted to categorize the research questions by scientific discipline.  Under a given priority one might find questions for oceanographers, basic biologists, and economists or anthropologists.  The solutions to these problems require collaboration between disciplines and between science and industry.  The first step is to articulate the questions in such a way that researchers and industry are exposed to the question's rich context. In every workshop there were questions and suggestions about management process and communication between fishermen, scientists, and managers.  We have included these observations and suggestions in the report.  We have not included specific suggestions for management measures because those fall outside the scope of this study.    

   

VI.  Priority Research Questions

Research Context and Group Research Priorities

Lobster research priorities are driven by the tension between the federal/ASMFC determination that the lobster fishery is overfished and the increase in abundance and  landings in the last 20 years.  Overfishing is defined as that stock level where the estimate of egg production per recruit (EPR) is 10% or less of that in an unharvested population.  Currently the Gulf of Maine is at 3.2% EPR and is deemed to be overfished.  Simultaneous predictions of stock collapse and record abundance result in fundamental questions:  Why do we have this abundance?  Where are the bottlenecks for this population?  Does the population really have egg production that is too low?  What is driving recruitment?  What effect do large and fine scale oceanographic events have on the population? 

At both meetings participants stressed the need to integrate Canadian research efforts and findings into our own. 

   

Lobster Priority 1:  Oceanography 

The source and sink for lobster larvae remains the dominant research question for the lobster industry.  This is an area that has had considerable research attention in the last 15 years and that work has yielded new insights that in turn are producing new areas of research.  Management questions about the relationship of the inshore and offshore lobster stocks and the value given in the assessment to the V-notched and oversize lobsters off the Maine continue to make this research directly pertinent to the future of the Maine lobster industry. 

Priority research needs are: 

a)  Determine the lobster broodstock source for larval settlement and harvest areas and the relationship and relative contributions of the inshore and offshore broodstock.
b)  Study nearshore oceanography to understand its impact on larval transport and settlement for lobsters. 
c)  Study the effect of water quality on lobster reproduction, growth, and health including chlorine, herbicides and pesticides, and nutrients.
d)  Are there large-scale oceanographic or climatic influences causing the reduced lobster larval settlement in the last five years?  If so, through what factors or mechanisms are those influences operating?


“Oceanography figures strongly in the early life history of lobsters because the larvae and postlarvae must survive (so growth rates, prey and predators matter) and because the strong residual flows in the Gulf transport larvae potentially long distances.” 

Lewis S. Incze, Ph.D.
Attachment B 

   

Lobster Priority 2:  Assessment 

The lobster stock assessment is the focal point of all of the disagreement about lobster population dynamics.  As a result, for the lobster industry, the assessment provides the lens through which they see lobster science questions.  There is interest in both improving the data and assumptions that go into the model and developing new models.  In the process of improving data, there is interest in developing new ways to monitor the health of the lobster population.  

New indices that were discussed included larval surveys, post settlement surveys, and ventless trap juvenile surveys.  Fishermen are interested in participating in the ongoing monitoring and concerned that the modelers involved in the assessment be able to use the information. 

Maine dominates the fishery in New England but until recently, little data from the Maine fishery was integrated into the federal stock assessment.  Two types of data were missing:  biological information about the make-up of the stock and fishery independent data.  In the last few years, that has started to change.  Sea sampling is particularly important in the lobster fishery because the fishery is regulated to prohibit landing juveniles, breeders, and large adults.  For this reason, port sampling or landings data will not provide information about those elements of the population.  Maine has had a limited sea sampling program for years, but data from it was not used in the federal process.  Now Maine has expanded its sea sampling, including an ongoing experiment with electronic data gathering and is providing the information to the assessment process. 

Fishery independent data is meant to provide an index of abundance and normally comes from a trawl survey.  Maine and New Hampshire have been the only New England states without an inshore trawl survey.  Furthermore, the federal survey does not come very far inshore in the eastern Gulf of Maine because of the bottom topography.  As a result, fishery independent information has been missing from the most productive area for lobster in the Gulf of Maine.  In 2000, Maine is initiating an inshore trawl survey. 

Priority research needs are:

a)  Document lobster abundance in Maine fishing areas through fishery independent means such as a trawl survey.
b)  Research lobster stock structure and migration patterns so that management areas can be made consistent with stock structure. 
c)  Explore new models for lobster assessment and incorporate into models multiple indicators of stock health including results of new collaborative monitoring.
d)  Systematically improve research on inputs to the lobster assessment model such as natural mortality, growth rates and age, size composition of population and catch, measurement of fishing effort, lobster behavior and migration. 


“There is a need for targeted onetime research, such as developing a technique to age lobster, but we must remember that consistent monitoring programs are the cornerstone for assessments.” 

Carl Wilson

Attachment C 

“…these biological attributes have important implications for harvest policies … A heavily armored species that lives for 50+ years, produces a relatively small number of eggs, and attains a large size must have evolved under environmental conditions that favored such characteristics.”  

Paul Rago, Ph.D.

Attachment D

   

Lobster Priority 3:  Life History and Behavior

As with all crustaceans, there is no established technique to age lobster.  This puts a premium on studies of lobster growth because without better understanding growth rates, there is no way to link the settlement survey information to later harvest information. Research in the last five years has demonstrated a strong positive relationship between the number of lobster post larvae in the water, and the number of juvenile lobsters on the bottom in that area.  That work, and another time series that started in 1989, has shown a downturn in abundance starting in 1996.  Does this predict a downturn in the fishery in the next few years?  If so, why is it occurring? 
 
Priority research needs are:

a)      Improve the understanding of lobster growth rates, particularly of juveniles, in order to be able to link strength of post settlement year classes to future catch. 
b)      Improve/develop better sampling procedures to monitor juvenile lobster abundance:  fishery independent and fishery dependent. 
c)      Understand migration and movement of lobster post larvae, juveniles, and especially broodstock. 


“To what extent does egg production in one area contribute larval settlement and harvests in another?  The exchange of lobsters among stock assessment areas,  in-, off- and along-shore, remains poorly understood.” 

“However, trap-and trawl-based samples have their own problems related to size-selectivity and differences in sampling efficiency on different habitats.  These biases need to be evaluated and corrected-for in order to relate data collected by the different methods.” 

Richard A. Wahle, Ph.D.

Attachment E 

   

Lobster Priority 4:  Socio-economic Issues 

If lobster landings fall even to the long-term average, they will be reduced by more than 50% of current landings.  This situation will pose serious social and economic problems for the coastal communities that are now so dependent on lobstering. 

Articulation of economics and policy research questions is not as familiar turf for the industry as are biological and oceanographic questions.  Economic contingency planning for an almost guaranteed eventual downturn received highest priority from the group.  A first step in this planning process is information gathering about debt load in the industry, since that will determine the capacity of the industry to respond to lower landings.  

In addition, considerable discussion occurred about the fact that normal economic studies of the industry miss significant subtleties about the business that, in fact, determine behavior.  The industry wants policy makers to understand the nature and significance of the variation that exists within the industry:  there are many different business strategies, situations, and expectations that occur.  It also wants documentation of the profound changes in lobstering since the 1950s.  Those changes include the shift from making a living to seeking the good life, dramatic changes in technology from haulers to wire traps to electronics.  When combined with technological changes, the abundance of lobster resulted in it being much easier to succeed lobstering, so the business saw a pulse of new effort.  These changes have undermined a number of the traditional checks on the business, including the integrity of the informal territories. 

The democratic zone process is a huge experiment in democratic resource management decision-making.  It has had a rocky start, yet the participants at the lobster meetings did not place a high priority on improving the functioning of zones.  Much of the discussion was about zone issues, but the group did not identify types of socio-economic work that could assist the process.

Priority research needs are:

a)  Prepare a comprehensive response plan in the event of a sharp decrease in lobster landings and recommend actions to prepare the industry and coastal communities prior to a downturn with particular analysis of the impact of current debt load. 
b)  Strengthen industry input and participation in science from the lobster management zones so that it becomes a continuous, ongoing process.
c)  Describe the lobster fishery:  economics, the many different businesses and fishing strategies that exist within the industry, effect of loss of alternative fisheries, and changes since 1950s. 
d)  Provide social and economic descriptive material about the lobster fishery to support state interests in federal and interstate management arenas. 


“It is quite likely that the current high lobster harvest levels will start to decline sometime in the near future …  What steps can the industry and State take to generate warnings of this decline and what options do the State, the zone councils and the industry in general have for responding to this decline?” 

James A. Wilson, Ph.D.

Attachment F

   

Additional topics:

Two issues that were not part of the planned discussion were given high priority by the participants: 

1.   Lobster health and disease issues.
2.   Research into the hypothesis that lobsters are being "farmed," fed by the high number of baited traps on the bottom. 

Finally, two ideas were discussed that could serve as organizing principles for a major research project were discussed. 

1.   “Year of the Lobster:”  a bilateral, one-year, intensive, sampling project that would involve many researchers and industry members in both United States and Canada. 
2.   Role of Technology:  an expanded study of the quantitative and qualitative issues, such as the impact of changed fishing patterns, in documenting lobster fishing effort.   

   

VII.  Lobster Observations and Questions from Discussion 

Assessment models

Need a new, better definition of overfishing.  Canadians use a different one.  

Incorporate multiple measurements into definition of overfishing. 

Overfishing designation in light of increased landings and high abundance creates a credibility problem. 

Look at alternative assessment models used internationally. 

Use multiple indicators to track and assess trends. Add other measures, indices to stock assessment.  

Assessment should provide information about the strength of incoming year classes.  Fishermen would buy in to recommendations and effort could be adjusted to size of year class (as is done in the shrimp fishery).

Develop spatially explicit population models that evaluate the consequences of meta-population dynamics to the sustainability of the resource. 

The three ASMFC management areas are a problem because the movement of larvae and big lobsters between areas and inshore, offshore, and along shore is poorly understood.

Assessment Surveys, Indices, and Inputs 

Maintain a regional time series of oceanographic data and abundance indices for juvenile, pre-recruit, and harvestable segments of lobster life history.   From that data time series, evaluate the power of oceanographic data, and juvenile and pre-recruit abundance indices to predict harvests. 

Develop coast wide larval monitoring plan using independent monitors (fishermen).  

Tagging and monitoring experiments that involve fishermen should be ongoing all the time.  Fishermen who have fished more than 50 years will say they know less at the end than they did at the start.  There is so much to learn. 

Use urchin divers to get information on sublegal lobsters.  

Continue development of ventless trap survey method. 

Continue development of onboard computer data collection system.  

Characterize the seasonal and spatial pattern of fishing effort and landings using electronic reporting. 

Monitor indicators of population stress

-         Fraction of newly molted lobsters in total landings|
-         multiple recapture rates
-         incidence of disease
-         Indicators of non-lethal gear encounters— e.g., culls
-         reliance on recently mature lobsters for egg production
-         identify zones or pockets of declining catch rates

Conduct large-scale experiments such as closing an area and comparing it to an appropriate control area or doing comparative analyses with Canada, zones within Maine, etc. 

Need more fisheries independent data, such as one get from a trawl survey, because it would give an independent measure of abundance. 

Maine should contribute more sea sampling data to the stock assessment process:  both current and historical information.  Need more test sites in local areas. 

Need assessment more often than every five years. 

Incorporate Canadian information into assessment. Need better landings statistics.  

Need better estimates of abundance at each stage:  early settlement, juveniles, recruits into harvest, oversize.  At each stage need to know abundance, movement, distribution, mortality.

Do inshore surveys in the primary fishing areas for better abundance estimates 

Develop new monitoring methods for fishery independent surveys such as trap surveys, photographic, mark-recapture etc. 

Develop fishery-dependent surveys such as ventless traps. 

Develop a better description and measure of fishing effort.  

Communication 

Juvenile traps should be given to lobstermen.  These concrete observations are necessary in order for fishermen to believe what science is saying. 

Research results should be easily accessible to everyone, including Canadian information.

Create opportunities for dialogue apart from regulatory environment. 

Need to build trust between fishermen and researchers. 

Currently, when landings are high, lobster is said to be overfished.  When lobster landings decline, lobsters are also overfished.  Creates credibility problem. 

Goal of achieving at least F10 is seen as unrealistic. 

Disease 

Overpopulation of lobster is leading to disease.  Increasing the egg production could be a disaster.  

Monitor lobster health in light of experience in Long Island Sound. 

Ecology 

What effect does the huge number of seals, shags have on the lobster population? 

What is the effect of boat traffic on post larvae?  

Need more focus on understanding how the system works and the interactions between species than fine tuning the assessment.  

What are the effects of other fisheries on the lobster fishery? 

Are traps harmful or helpful in protecting from predators, providing feeding stations? 

Ghost gear is a critical issue.  Need a policy to allow it to be harvested and salvaged. 

Effort 

How has fishing effort changed over time?  Characterize and quantify the important changes in the fishery such as the change from wood to wire in traps. 

Need to better characterize and measure fishing effort. 

Gear technology has a huge effect on effort.  (Wood vs. wire, heads, etc.) 

Economics (price) affects effort.  If price goes down, effort will slack off.

Environmental issues

What is the effect of sewage treatment chemicals, nutrients, herbicides, and pesticides on lobster populations? 

What are the effects of spraying for brown tail moth, golf course chemicals on lobsters? What is the impact of global climate change on the lobster population? 

What are the effects of dredging and dumping on lobster populations? 

Why is the population high in Boston Harbor when surrounding areas are down? 

What is the effect of salmon farms on water quality and the lobster population? 

Growth 

What is the effect of bait on the lobster population?  Will rawhide bait have negative effects? 

Need studies of growth rate:  post larval, immediate pre-recruits (juveniles) in order to be able to link strength of post settlement year classes to catch.

Determine the age-size relationship regionally, especially the variance in size with age.  Continue to search for more reliable indicators of age than body size. 

What is the role of climate and environment on sex of lobsters?  They are not differentiated until they are 9 mm. 

Life History 

Effect of bait on lobster population.  Are lobsters dependent on it? 

Test the effect of bait on lobster population and growth rates.  

What is the effect on the population of taking offshore egg bearers? 

What is the effect of inshore spawning lobsters on the population? 

Document frequency of egg-out, molting, and multiple egging out.  

Increase the number of lobster settlement test sites at least to one per zone.  

Intertidal monitoring, less expensive, tracks with data from subtidal zone.  

What factors affect larval survival?  

Management 

Study the effect of increasing the minimum sizes. 

Evaluate effect of Maine conservation measures by comparing Maine and Rhode Island lobster populations. 

Document contribution of Maine's conservation measures on population south of here.

Monitor the effectiveness of management measures such as the incidence of V-notches and within season changes and the abundance of oversized lobsters. 

Develop fishery response plans for emergencies. 

Evaluate the effectiveness of v-notch as management tool. 

Management and assessment seem disconnected from real conservation actions. 

Migration and Behavior 

Importance of size in lobster migration.  

What are oversize lobsters' migration patterns? What is the effect of barometric pressure on migration? 

Need lobster tagging studies. 

Loss of catch by in-trap mortality.  Large egg-bearing females attack smaller lobsters.  

To what extent does egg production in one area contribute larval settlement and harvests in another?  What role does migration play in this? 

Ultrasonic tag technology is improving, could be used to tag and track individuals. 

When, at what age/size does an individual start to migrate? It is rare to see a big v-notch. 

Do a tagging study in Penobscot Bay to assess the number of berried female lobsters there.  Is there a net gain or loss in the Bay?  Do all the lobsters leave in the fall or is there a resident population? 

Tagging in Mt. Desert Rock area could be important.  It is a hotbed of activity and may help discover relationships between inshore and offshore populations. 

Are there secret nursery grounds for juvenile lobsters in the Gulf of Maine?  Apparently in Long Island Sound there are three-foot tunnels under the mud. 

Are there nursery areas that should be protected?

Oceanography

What is the distribution and timing of egg hatching?  Use this to put into model assumptions.  

Use field data on larval and postlarval distributions to test the simulations.  

What are the connections and dependencies between offshore lobsters, the inshore fishery and inshore recruitment?  Do larvae from offshore subsidize the inshore fishery?  If so, how?

Of the adult lobsters, what proportion of the population remains offshore and what proportion migrates shoreward? 

Use oceanography (temperature, current, wind) to forecast larval movement and settlement. 

To what extent does egg production in one area contribute larval settlement and harvests in another?  What role does larval transport play in this?  

Document nearshore currents all along the coast. 

Predation 

Could surprisingly high harvests in an area be due to lack of predators? 

Reproduction 

As aquaculture grows in other places, eggs may become our most valuable asset. 

What are the characteristics of the broodstock?  Need to know frequency of spawning by age/size of female.  How many eggs per lobster? 

What is the importance of large females to the fishery?  Do they contribute more eggs?  Do their eggs have a higher survival rate? 

Quantify and assess broodstock. 

Observe more red (unfertilized) eggs on lobsters.  Why? 

What is the contribution of larval production inshore?  

What is the relationship between inshore and offshore larval production?

Socio-economic issues

What steps can the industry and State take to generate warnings of if the lobster resource starts to decline?  What options do the State, the zone councils and the industry in general have for responding to this decline? 

If lobster abundance went down would effort increase or decrease? 

How much is invested in the lobster fishery and what is the level of indebtedness by age of lobsterman? 

Economic impact studies miss individual debt load. Examine the impact of changes in management on the value of a permit or license. 

What is the threshold income to make it worthwhile to fish? 

What are exit strategies for lobster fishermen? 

Document the status of the fishery by a port-by-port survey similar to the 1880s U.S. Fish Commission survey. 

Describe profile of various different lobstering strategies within industry. 

NMFS has taken away one fishery at a time (groundfish, tuna, etc.) so we are very dependent on lobstering. 

Do more analysis and description of the impacts of management forcing fishermen into a single fishery.  

Competition cycle:  higher costs, need more traps, more to compete with neighbor. 

Wire traps make a huge difference. 

Expectations have changed in the fishery:  people want the good life, not a living. 

Traditionally boundaries prevented fishermen from moving.  Now fishermen want to move when they hear the fishing is good and want to break boundaries. 

In Zone G, what is the economic impact of the inshore fishery and the offshore fishery?  

How to protect traditional fishing practices without micromanaging or privatizing the resource? 

Concerns that the family fishery will become a corporate fishery.  

People on zone boundaries are not well served. 

Examine zones and catch data by zone to see if zones match the biology. 

Analyze the effects of zone boundaries on fishermen. 

What is needed to make zones function better.  Successful industries in shoreside business tend to develop networks of people who converse and inform each other.  Is there any better way to get fishermen in zones talking? 

People who fish outside three miles don't feel it is fair that they have to declare a zone.  

Evaluate the effect of management measures on behavior, effort, and economics.  Some rules do the exact opposite of what is intended.  

Are there basic ground rules, principles, that the industry could buy into to help them deal with fishery management decisions and decisions necessary in the event of a decrease in lobster abundance?

   

Attachment A: 

AMERICAN LOBSTER RESEARCH PRIORITIES 

MEETING ATTENDEES 

April 25, 2000 at Samoset Resort, Rockport 

30 Participants 

Lew Incze               Bigelow Lab, West Boothbay Harbor 04575              633-9600
Barry Hamilton        S-S Seaweed, Camden                                           236-9602
Jay Smith               Nobleboro                                                              563-5208
Larry Peter              Rockland                                                               594-7054
Ernie Squires           S & S Seafood, Rockland                                       594-5088
Bob Brown               ME Import Export Lobster Dealers Association         882-7781
John Butler              19 Chamberlain Road, Scarborough 04074               883-5457
Bill Doane                South Portland                                                      775-5448
Lyman Kennedy        Falmouth                                                              781-4662
Arthur Pierce, Sr.      P.O. Box 134, Sebasco Estates 04565                   389-1177
Marilyn Hotch           92 Bellevue Street, Owls Head 04854                      596-7847
Laura Taylor             DMR, Augusta                                                       624-6576
Carl Wilson              DMR, Boothbay Harbor                                           633-9538
Linda Mercer            DMR, Boothbay                                                      633-9525
Sara Ellis                 The Lobster Conservancy
                               P.O. Box 235, Friendship 04557                             832-8224
Butch Bowie             P.O. Box 273, Windsor 04363                                549-0996
Gaye Robinson         P.O. Box 281, Warren 04864                                  273-2527
Glenn Nutting           DMR, Boothbay Harbor                                           633-9514
Corrie Roberts          Island Institute, 410 Main Street
                               Rockland 04841                                                     594-9209
Ben Neal                  Island Institute, 410 Main Street
                               Rockland 04841                                                     594-9209
Eric Annis                UM Darling Marine Center, Walpole 04573                563-3146
Rick Wahle              Bigelow Lab, West Boothbay Harbor 04575               633-9659
Tim Harkins             Icebrand Seafoods  92 Waldren Way, Prtlnd, 04112   797-2850
Patrice Farrey          P.O. Box 321, York Beach 03910                             363-6783
Pat White                41 Route 103, York 03909                                        363-6783
Vernon Thompson    P.O. Box 176, Port Clyde 04855                               372-8831
Sue Inches              DMR, Augusta                                                         624- 6558
Dana Morse             Sea Grant/UM Cooperative Extension                     563-3146 x205
Don Perkins             Gulf of Maine Aquarium  PO Box 7549, Prtlnd 04112  871-7804
Robin Alden             P.O. Box 274, Stonington 04681                               367-2473

 April 27, 2000 at White Birches, Ellsworth, ME 

38 Participants           

Jen Bubar               P.O. Box 317, Stonington 04681                             367-2417
Rick Bubar              P.O. Box 317, Stonington 04681                             367-2417
Rick Wahle             Bigelow Lab, West Boothbay Harbor 04575              633-9600
Ted Hoskins            P.O. Box 931, Blue Hill 04614                                374-2028
Jim Haskell             P.O. Box 40, Union Trust, Milbridge 04658               546-7052
Jason Mibell           117 Great Lory Road, Lamoine 04605                       667-0358
Bonnie Crosby        P.O. Box 86, Clay Cove, Steuben 04680                  546-7052
Dan Hodgkins         HC 77, Box 442, Hancock 04640                             442-6570
Herb Hodgkins        HC 77, Box 445, Hancock 04640                             442-6238
Dave Hiltz               P.O. Box 117, Isle Au Haut 04645                           335-2611
Dan MacDonald       P.O. Box 81, Isle Au Haut 04645                             335-5577
Ted Ames               P.O. Box 274, Stonington 04681                              367-2473
Anne Porter             P.O. Box 509, Ellsworth 04605                                667-2576
Roger Chipman        P.O. Box 72, Birch Harbor                                       963-2391
John Chipman          P.O. Box 76, Birch Harbor                                       963-7051
Bill Anderson           RFD 2, Box 3100, Lubec 04652                                733-2179
Eric Annis               UM Darling Marine Center, Walpole 04573                 563-7511
Carin Poeschel        448 Main Street, Orono 04473                                  866-5983
Carlton F. Joyce      12 Grindle Hill Road, Swans Island 04685                  526-4251
Leroy Bridges           RR 2, Box 521A, Deer Isle 04627                             348-6992
Linda Mercer            DMR, Boothbay Harbor                                            633-9565
Stephen Robbins III   P.O. Box 649, Stonington 04681                              367-5517
Carl Wilson               DMR, Boothbay Harbor                                           633-9538
Lew Incze                 Bigelow Lab, West Boothbay Harbor 04575               633-9600
Michael Dunnington   Bigelow Lab, West Boothbay Harbor 04575               633-9600
Frank Donnelly          15 Ash Lane, Lamoine 04605                                   667-0287
Mazy Myers              P.O. Box 345, Hancock 04640                                 422-4741
Ollie Wenger             RR 1, Box 2325, Bar Harbor 04609                           288-5228
Kelli Wenger             RR 1, Box 2325, Bar Harbor 04609                            288-5228
Dick Bridges             P.O. Box 27, Sunset 04683                                      348-2840
Carol Bridges            P.O. Box 27, Sunset 04683                                      348-2840
Bob Bayer                University of Maine, Hitchner Hall, Orono 04469          581-2785
Bryan Pearce            University of Maine, Boardman Hall, Orono 04469       581-1216
Bill Crowe                 P.O. Box 253, Gouldsboro 04607                              963-7195
Jennifer Smith           DMR, Boothbay Harbor                                            633-9599
Sherman Hoyt           Sea Grant/UM Cooperative Extension                     800-244-2104
Don Perkins              Gulf of Maine Aquarium PO Box 7549, Prtlnd 04112    871-7804
Robin Alden               P.O. Box 274, Stonington 04681                              367-2473

   Attachment B:

Oceanography and the Early Life Stages of Lobsters 

Lewis S. Incze, Ph.D., Bigelow Laboratory for Ocean Sciences 

Maine DMR Coastal Fishery Research Priority Meetings 

April 25 and April 27, 2000 

At hatching, each lobster egg produces a single larva, the first of four free-living planktonic stages that live in the upper part of the water column.  The depths of the first three larval stages are not well known and may vary between locations.  The last stage, called a postlarva, lives close to the surface in most areas where it has been sampled--usually within the upper 1 meter (m) (39 inches)  The postlarva eventually settles to the bottom to become a Young-of-Year (YOY) lobster.  Most YOY in Maine have been found in cobble habitat less about 10 m  (33 feet) below mean low water.  Settlement may occur in offshore waters, but little is known about it.  

The rate of development of larval and postlarval lobsters is strongly temperature-dependent, being faster at warmer temperatures.  A typical development time for lobsters hatched in mid-coastal Maine is about 50 days based on laboratory studies, but seasonal warming, individual differences and strong spatial gradients in temperature produce a wide range of development times.  In the Boothbay region where it has been studied, settlement occurs mostly from mid-July to early September, corresponding with the seasonal appearance of postlarvae.  Postlarvae are not abundant as larval forms go.  In seven years of sampling in Johns Bay and off Damariscove Island, 75% of the tows had postlarvae concentrations <10/1000 m2 (less than 10 per 1000 square meters of sea surface area) and more than half the tows had <5/1000 m2 (1000 square meters is approximately 1200 square yards).  However, our experience is that they are quite widespread.  In contrast, typical settlement densities in cobble habitat are 1-4 YOY/m2.  Our work shows that currents, 6 or more weeks of postlarvae availability, and site selection by the postlarvae enable this concentrating effect from a few per 1000 m2  at the postlarvae stage to a few per m2 after they settle and become young of the year. 

Because the planktonic stages are long-lived, they can be moved considerable distances around the Gulf by currents.  Most of the currents we observe in coastal waters are tidal, but underlying these strong flows is a residual flow that is the net movement of water after the tides have been "subtracted."  One can visualize this by considering that a floating particle usually does not return to exactly the same spot after a tidal cycle.  Some of the displacement is due to lateral mixing processes (a random process), but regular directional displacements also may occur (that is, over several tidal cycles the displacements are in the same direction and a similar distance after each tide).  These average “subtidal” flows are typically calculated from data collected by drifters of various types (today, satellite-tracked drifters are used) and by special current-measuring devices on moorings and ships.  Since the residual circulation in the Gulf is driven primarily by density (temperature and salinity) differences, it can be closely estimated in open waters from hydrographic profiles (vertical temperature and salinity measurements). These are routinely made during research cruises.  Finally, since the postlarvae live near the ocean's surface, they are particularly prone to wind-generated transport.  The sea breeze typical of coastal summer air flow in the Gulf of Maine may play an important role in the shoreward movement of this final stage toward known settlement habitats.   Whether this contributes to interannual differences in recruitment is currently being studied. 

The Gulf of Maine is characterized by a strong counter-clockwise circulation which is produced by comparatively fresh water near the coast, salty slope water in the interior of the Gulf, and the Earth's rotation (Coriolis effects).  The flows are modified by local topography and tidal energy, freshwater inputs (rivers), and seasonal and interannual weather patterns.  The result is a system of coastal currents and gyres, the latter around major basins (because of saltier water at depth) and banks (because of steep topography).  Some of these features are well described and predictable in an average sense, e.g., the Eastern and Western Maine Coastal Currents, Jordan Basin gyre and Georges Bank gyre.  However, we need to know much more about the variability of these flows and the specific biological and chemical events taking place within them and the rest of the system if we are to understand processes such as fisheries recruitment.  While studying mechanisms that affect recruitment from year to year, we cannot forget that many of the conditions in the Gulf are connected with larger, "climate-scale" processes that influence precipitation, wind stress, cloud cover, atmospheric pressure, atmospheric heating and cooling, and the sources and volumes of Atlantic waters entering the Gulf.  Because of this complex setting and the interaction of many variables, we must think of lobster recruitment patterns and population trends in the context of a system with variability at a number of spatial and temporal scales.  Understanding the linkages is both a scientifically interesting challenge and a worthy goal in terms of how we approach the future of the fishery.  It is not, in any case, easy. 

Oceanography figures strongly in the early life history of lobsters because the larvae and postlarvae must survive (so growth rates, prey and predators matter) and because the strong residual flows in the Gulf transport larvae potentially long distances.  The spatial (geographic) and quantitative linkages ("how many make it") between egg hatching and eventual settlement have been of scientific interest for many years.  These are being studied in different ways.  I highlight four activities below which are taking place in Maine (related just to the planktonic stages), and comment on some of the research needs identified by them. 

1).  Modern circulation models, coupled with biological sub-models, are being used to simulate some aspects of larval transport, development and recruitment. The advantage of such models is that they can integrate and do the book-keeping on many complex processes simultaneously -- think of "tracking" the fate of a large number of lobster larvae through space and time when they originated from a variety of hatching locations and experienced varied oceanographic conditions along their trajectories.  It's not practical to think about doing this without a computer model.  Also, "electronic experiments" can be repeated with a model to examine the results of different variables and forcing, such as different hatching locations and times and different wind events.  One of the obvious limitations is that no model incorporates all of nature's complexity, so one must be careful how the model is used and how the results are interpreted.  Models are very good at testing ideas and identifying data needs, however, and models themselves are being refined and tested all the time.  If we are to understand the linkages between various parts of the Gulf of Maine lobster population, then field biology and oceanography will have to work with modeling efforts to understand larval production and transport pathways.  This is the process being used in a number of studies in other areas.  In recent modeling exercises in Maine, two of the major data needs that have been identified are:  1) the distribution and timing of egg hatching (what is the real pattern of production that we should put into the model?) and 2) field data on larval and postlarval distributions to test the simulations.  The first could be done with assistance from the industry; the latter would require research vessels and support from the relevant state and federal agencies in Canada and the U.S.  A great deal of coordination would be required to pull this off.  The Gulf of Maine is a multi-jurisdictional system, and any study should think of the entire geography. 

2).  The Inshore/Offshore Question.  What are the connections and dependencies between offshore lobsters, the inshore fishery and inshore recruitment?  Calculations (paper by M. Fogarty) show that a small subsidy from offshore could help sustain the heavy exploitation rates of the inshore fishery.  Such a subsidy could take place through migrations or through larval inputs, or both.  We don't have the data needed to test either idea, and meanwhile, there is growing fishing pressure on the offshore population.  We know that larvae hatched offshore would be transported along the shelf in the prevailing westward coastal current system--would they also get transported to near shore?  Where? How?  How often? And under what conditions?  Of the adult lobsters, what proportion of the population remains offshore and what proportion migrates shoreward?  These questions are similar to those raised in topic #1 above, but are specific to the inshore/offshore question and so are identified in greater detail here.  It is worth pointing out that in 1999, I found VERY FEW postlarvae inshore of Matinicus Island despite extensive sampling as part of the Penobscot Bay Collaborative (see next section).  Yet, in a short survey along the coast from Pemaquid to Grand Manan, University of Maine graduate student Eric Annis found good numbers offshore (typical of the numbers I used to see in the Boothbay and Seabrook areas prior to 1995).  Is this usual?  Do the inshore and offshore waters generally do their own thing, or are they usually connected in a way that didn't happen in 1999?  Is the apparently low postlarvae supply in Penobscot Bay in 1999 (the first year of extensive sampling) related to the low recruitment observed at Boothbay and the low postlarvae supply sampled at Seabrook?  If this is part of an over-all pattern, is the same mechanism responsible? 

3).  The Penobscot Bay Collaborative is a multi-institutional, inter-disciplinary study of circulation and lobster recruitment in Penobscot Bay.  Components of the study include satellite remote sensing (sea surface temperature and chlorophyll patterns), circulation, plankton distributions (larval and postlarval lobster), and all of the benthic life stages of lobsters.  The objectives are to understand the connections between Penobscot Bay and the coastal current system; to understand how lobsters recruit to this very productive bay (for instance, what proportion of the lobsters harvested in Penobscot Bay come from egg production inside the bay, and what proportion from outside?); and to see if satellite data can be used to monitor changes in circulation and predict consequent changes in lobster recruitment.  Numerous lobstermen have been involved in this study, following our results, sharing ideas and helping with data collection (primarily tagging and other sea sampling).  We have gained new insights into circulation in the bay and are making progress with understanding and modeling mechanisms that can affect recruitment.  Funding has been crucial to bringing people together on this topic (several of them are not usually involved in lobster studies), providing resources to do the work, and maintaining focus.  Funding will be crucial to continued progress. 

4).  Recruitment and Postlarval Time-Series.  Early work (1989-1995) on postlarval lobsters and young of the year (YOY) recruitment (the latter by R. Wahle) in the Boothbay region was instrumental in establishing that there is a strong positive relationship between the supply of postlarvae to the nearshore environment and the abundance of early benthic stages, and that these could show strong interannual variations.  The research funding which made the initial work possible ended in 1995, but the state has funded YOY monitoring since. This monitoring has turned out to be very valuable (see below).  Meanwhile, the electric generating plant in Seabrook, NH has sampled postlarvae every year since 1989 as part of their environmental monitoring requirements.  They have generously provided their data to me for scientific purposes, and these data now constitute the longest time-series of postlarvae in the Gulf of Maine.  

Both the YOY data from Boothbay and the postlarvae data from Seabrook show a reduction of about 50% after 1995 (that is, low numbers from 1996 through 1999).  We do not have prior experience with "early warnings" of this sort, so we do not know for sure how this will translate into the fishery.  However, data from R. Steneck and co-workers indicate that the abundance of juvenile and harvestable lobsters along the coast follows the same spatial pattern as the settlement densities.  These findings suggest that a downturn in the fishery in the western part of the state is likely since the decreased recruitment took place several years in a row.  We are working on a formal set of calculations for these data, the biggest question being whether the two sites are representative of settlement along the substantial intervening section of coastline.  The lesson from our findings to date is that time-series are important, cluing us in to a possible downturn (of concern to fishermen and managers) and indicating that the cause of this downturn, if it materializes, will have been the plankton and the very earliest steps in recruitment.  This immediately raises several questions:  was the reduced postlarvae abundance and YOY settlement somehow related to low egg production; to low larval survival rates in the plankton; or to unfavorable transport pathways?  Whatever the explanation, why has it now occurred several years in a row?  Is this part of a "regime shift" in the biology or physics of the Gulf?  We have little data with which to answer these questions, and the absence of such data is the final lesson here.  If, indeed, the lobster harvest shows a sharp decline in the next few years, there will be much more interest in understanding the basic mechanisms of recruitment.  I repeat that WE DO NOT KNOW HOW THESE OBSERVATIONS WILL TRANSLATE INTO THE FISHERY.  We feel it is responsible to share our findings at this time, to be honest about what we don't know, and to stress that we need to know these things better.  By this I am promoting both the need for research and the need for open communication of ideas and results.

   

Attachment C:

Lobster Stock Assessments:  Current Approaches and Future Needs 

Carl Wilson, Maine Department of Marine Resources 

Maine DMR Coastal Fishery Research Priority Meetings 

April 25, 2000 

The lobster fishery is the most valuable fishery in the Northeast.  Maine landed an estimated 53.5 million pounds valued at $185 million in 1999.  Landings have doubled since the early 1980s.  There is evidence that lobster abundance is a record levels, but unprecedented levels of fishing effort have maintained a tenuous relationship between abundance and removal by the fishery.  This relationship has spawned heated debates on the status of the lobster resource.  It is the job of stock assessments to review the status of the resource through fishery dependant and independent measures. 

The assessment reports on trends in abundance, recruitment, size composition, egg production and fishing mortality. This information is used as a way to compare where the fishery is in relation to targets and thresholds established in the Federal Management Plan (FMP). If the fishery is thought to be approaching threshold levels then management actions may be taken.  By definition, lobsters are overfished when the egg production per recruit (EPR) is 10% or less than it would be in an unharvested population.  Currently the Gulf of Maine is at 3.2% EPR and is thus thought to be overfished.  There are a number of areas where further research and long-term monitoring can be inserted into the assessment process that should help our knowledge of the lobster resource. 

Current fishery dependent information comes from at-sea and port sampling programs.  This is critical information to describe what is being caught and landed in traps.  Sea sampling also gives us an idea what lobsters are discarded, such as short, egg bearing and v-notched lobsters.  In Maine the lobster fishery is a passive gear (trap) fishery which implies that lobsters choose to enter and subsequently get caught.  Fishery dependant measures therefore rely on variable conditions such as lobster behavior, gear selection, and the environment.  Improvements in fishery dependant data being collected might include: 

  1. An evaluation of the statistical coverage needed for a sea sampling program

  2. A juvenile/oversize lobster survey through modified traps

  3. Measures of the spatial extent of fishing through logbooks, electronic tracking

  4. Further development and definition of what effort is in the lobster fishery

  5. Research on trapability and lobster behavior

Fishery independent methods measure the lobster resource using techniques other than standard lobster traps such as trawl, submarine, and scuba surveys.  Currently the National Marine Fisheries Service trawl survey (largely based outside state waters) is not surveying areas where the highest fishing effort is located.  There has been little support of fishery independent surveys other than trawl surveys in the assessment process.  Improvements in and emphasis on fishery independent surveys for assessments may include: 

  1. Coast-wide surveys targeting newly settled and juvenile lobsters

  2. An inshore trawl survey

  3. Plankton sampling

  4. ROV or submarine surveys to index lobsters in areas where trawl surveys can’t work such as highly irregular habitats

Finally, mathematical models are used in assessments to fill in the gaps in our knowledge and make predictions of the stock.  Models are only as good as the information going into them.  There is a belief that the current Egg Per Recruit (EPR) model is not characterizing the lobster resource.  The EPR is tied directly into the current management FMP, and carries a substantial amount of weight in the regulation of the lobster resource.  Investigation of the applicability of the current model needs to be conducted.  Until we can count every lobster in the Gulf of Maine, we will need models.  Models in general could benefit from a better knowledge of: 

  1. Natural mortality

  2. Fishing effort and mortality

  3. Lobster behavior

  4. Lobster growth and age

Assessments should be used as a way to report on the status of the fishery and make forecasts for the future.  Management plans should be based on the best available assessment information.  Through further development of models, and fishery independent/dependent measures we can improve our estimates of the status of the resource.  There is a need for targeted onetime research, such as developing a technique to age lobster, but we must remember that consistent monitoring programs are the cornerstone for assessments.


   

Attachment D:

Critical Research Needs for Lobster Assessment and Management 

Paul Rago, Ph.D.,  National Marine Fisheries Service 

Maine DMR Coastal Fishery Research Priority Meetings 

April 27, 2000 

Lobsters support the most valuable single species fishery in the northeast United States.  Despite its economic value and the persistence of high landings in recent years, much remains to be learned about the species and the fisheries that harvest it.  The purpose of this essay is to suggest a number of areas in which the science underlying lobster management could be improved. The opinions expressed in this essay do not represent those of National Marine Fisheries Service (NMFS) but at least some of these suggestions might find broad support.  

The basic process of stock assessment begins with a review of the fishery — the magnitude and biological characteristics of the landings, the amount of fishing effort expended, and the seasonal and spatial distribution landings and effort.  These fishery dependent measures are compared to fishery independent indices of abundance — typically trawl surveys, and various mathematical models are applied to estimate the rate of exploitation.  In and of itself, the rate of exploitation means little; it must be evaluated with respect  to the life history of the animal.  The biological features and ecological role of lobsters have been shaped by millions of years of evolution.  As such, scientists, managers, and fishermen recognize that these biological attributes have important implications for harvest policies. The maximum possible rate of harvesting is ultimately constrained by these attributes.  A heavily armored species that lives for 50+ years, produces a relatively small number of eggs, and attains a large size must have evolved under environmental conditions that favored such characteristics.   These characteristics can be captured in a mathematical model that predicts the expected lifetime production of eggs for the “average” female.   Exploitation can then be evaluated with respect to its impact on what might be expected in the absence of the fishery. Many of the heated debates in recent decades have centered on this issue.  Simply stated, the overfishing definition recommends that lobsters should be given the opportunity to produce about one-tenth of what they might produce with no fishing. 

The point of the foregoing is not to debate the merits of the magnitude of the “one-tenth rule” or its immediate consequences for lobster management.  Instead, it is important to recognize that harvesting does impose some cost to the population and utilizes some fraction of the remarkable compensatory reserve that many species exhibit.   Perhaps the lobster can continue to withstand very high rates of exploitation, but it is worth noting that most species cannot— as verified by hundreds of collapsed finfish and shellfish fisheries around the world.  From a purely pragmatic viewpoint we can ask if it is worthwhile to conduct the experiment that will establish the limits of compensation in lobster populations.  If the economic fallout of a reduced lobster population is deemed inconsequential then the experiment is worthwhile. Otherwise, it would be prudent to improve the monitoring of this resource, detect early signs of stress, and plan responses to such information.  It might even be worth planning how to avoid such a result but such a discussion would surely divert our attention today. 

The preceding arguments suggest a number of useful lines of research.  Some of these suggestions are enhancements of ongoing work while others would require new research efforts. 

1.  Improve fishery independent surveys
        a. Survey the inshore resource in the primary fishing areas
        b. Develop new monitoring methods (possibilities — trap surveys, photographic, mark-recapture etc.) 

2.  Develop fishery-dependent surveys
        a. Monitor juvenile recruitment, especially ventless traps
        b. Develop measures of catch per unit effort
        c. Synoptic snapshot surveys — e.g.,  Christmas bird count 

3. Develop realistic measures of fishing effort and monitor changes over time
        a. Numbers and types of traps
        b. Soak time
        c. Seasonal deployment 

4.  Characterize the seasonal and spatial pattern of fishing effort and landings.
        a. Need broad base of support
        b. Electronic reporting 

5.  Monitor indicators of population stress
        a. Fraction of newly molted lobsters in total landings
        b. Multiple recapture rates
        c. Incidence of disease
        d. Indicators of non-lethal gear encounters — e.g., culls
        e. Reliance on recently mature lobsters for egg production
        f. Identify zones or pockets of declining catch rates 

6.  Conduct field and laboratory experiments to estimate growth rates 

7.  Conduct large-scale experiments
        a.  Closure area and an appropriate control area.
        b.  Comparative analyses with Canada, zones within Maine, etc. 

8.  Monitor the effectiveness of management measures
        a. Incidence of V-notches and within season changes
        b. Abundance of oversized lobsters 

9.      Develop fishery response plans for emergencies 

10. Create opportunities for dialogue apart from regulatory environment

   

Attachment E:

Research Priorities for Lobster Life History 

Richard A. Wahle, Ph.D.,  Bigelow Laboratory for Ocean Sciences 

Maine DMR Coastal Fishery Research Priority Meetings 

April 25 and April 27, 2000 

For this segment of the Research Priorities discussion I focused on major research questions for gaining a better understanding of lobster life history.  This is clearly a broad topic and there are many interesting research areas I could discuss.   But in this case my aim is to focus on the research areas that will improve our ability to assess the health of the lobster population and to forecast its upward or downward trends.  In short the question is, where can we get the biggest bang for our research buck? Here I briefly outline some recent scientific advances and identify where gaps still exist in data collection and modeling. 

There are relatively few cases in fisheries sciences where harvests are being forecast from the earliest life stages, years in advance of the harvest.  There is at least one however.  Harvests of the western Australian rock lobster have been accurately forecast since the 1970s.  In that case the yearly abundance of lobster postlarvae settling on artificial collectors suspended in the water column provide an index of the strength of the harvest 3-4 years later.  More recently the Australians have come to an understanding of how oceanography influences the fluctuations in settlement and now can forecast harvests from prior oceanographic conditions.  Fisheries scientists working with the American lobster have been trying to emulate the Australian example and some advances are being made in that direction.  

First, they have identified a direct correlation between the abundance of planktonic postlarvae and the strength of the newly settled year class on the bottom.  It was not until the late 1980s however that anyone knew how to quantify newly settled lobsters.  Artificial collectors like the Australian’s were ineffective.  Instead of this, a diver-operated suction sampling technique used in natural cobble nurseries has been adopted.  Since it is far more cost effective to sample the new settlers than the planktonic larvae, attention has moved to following year classes after settlement and ultimately to the harvest some 6-8 years later.  Still because settlement strength is determined by larval supply and larval supply may be determined largely by ocean processes it is important not to lose sight of the potentially strong influence of oceanographic conditions on subsequent harvests. 

It has been fairly easy to follow year classes over the first few years of life.  From the time series collected so far in Maine it appears that year-class strength still reflects settlement strength after at least two years.   After that age though, it becomes more difficult to follow year classes.   One reason is that there is no good way to estimate the age of a lobster.  Size is not a good index of age because some individuals grow faster than others and year classes eventually mix to the point of being indistinguishable by the time they reach harvestable size.  For predictive purposes then it is not only important to understand both the increase in average size, but the spread in size as well.   That will enable us to estimate the proportion of a year-class that has recruited to the fishery at a given age.   

A second reason it has been difficult to follow year-classes after the age of about two-years is that lobsters begin to emerge from nursery grounds and become more widely dispersed.  Although it has not yet been possible to follow year-classes through to the harvest, it is encouraging that regional differences in juvenile lobster abundance estimated by diver sampling correlate well with regional differences in landings.  For example, eastern Maine nurseries consistently have far lower lobster densities than western Maine grounds, a regional disparity long reflected in the landings per length of coastline. 

While diver-based methods have been increasing over the years, traditional lobster traps or bottom trawls may continue to be the sampling method of choice because of their widespread usage in the commercial fishery and the large areas they are capable of sampling.  However, trap- and trawl-based samples have their own problems related to size-selectivity and differences in sampling efficiency on different habitats.  These biases need to be evaluated and corrected-for in order to relate data collected by the different methods.  Mark-recapture techniques for estimating population size, gains, and losses may represent a means to reconcile the two sampling methods.  

Emergence from nurseries is only the beginning of a life-long expansion of the lobster’s range of movement.  Large reproductive lobsters are known to be capable of traveling hundreds of kilometers along the bottom.  Considering the combined effects of larval transport and benthic migrations a central question is: To what extent does egg production in one area contribute larval settlement and harvests in another?  The exchange of lobsters among stock assessment areas,  in-, off- and along-shore, remains poorly understood.  The implications for management are important though.  There has been growing recognition that many fish populations are in fact a network of subpopulations, collectively forming a metapopulation.  The strength or weakness of exchange among subpopulations can have important consequences for their dynamics and sustainability.  It makes little sense, then, to manage as separate, isolated stocks a species with such great potential for movement during its lifetime as the American lobster.  

A list of research priorities might include: 

• The need to maintain regional time series of oceanographic data and abundance indices for juvenile, pre-recruit, and harvestable segments of lobster life history.   
• From data time series, evaluate the power of oceanographic data, and juvenile and pre-recruit abundance indices to predict harvests.  
• Work out sampling biases inherent to trap- and trawl-based abundance estimates.  
• Determine the age-size relationship regionally, especially the variance in size with age. 
• Continue to search for more reliable indicators of age than body size. 
• Determine the extent to which egg production in one area contributes to larval settlement and ultimately harvest in another. 
• Develop spatially explicit population models that evaluate the consequences of meta-population dynamics to the sustainability of the resource. 

 

   

Attachment F:

Socio-economic Needs for the Lobster Fishery 

James A. Wilson, Ph.D., University of Maine 

Maine DMR Coastal Fishery Research Priority Meetings

 

April 27, 2000 

1)      It is quite likely that the current high lobster harvest levels will start to decline sometime in the near future.  It is not likely that the current high levels of fishing effort will leave the fishery very easily.  Fisheries managers often argue that this type of situation is very dangerous in a fishery because there are large amounts of effort chasing a naturally declining population.  The result can be a collapse.  Is this something the industry needs to worry about?  What steps can the industry and state government take to generate warnings of this decline and what options do the state, the zone councils and the industry in general have for responding to this decline?

2)      Develop harvest business models similar to those commonly used in agriculture by family farm operations.  Essentially these are very general models designed so that a single farmer or fisherman can set important parameters (e.g., months fished, number of traps fished in the month of x, and so on) for the purpose of tailoring the model to his particular way of doing business.  These models are used for developing business plans and/or analyzing production operations.

3)      Ways to facilitate the operation of the lobster zone councils: 

a)    Are there ways to streamline meetings, to resolve conflicts and generally make the councils operate more efficiently (i.e., with less cost in time and stress to the industry)?

b)    Are there ways to make the councils operate more effectively (i.e., initiate the interests of fishermen rather than responding always to demands from state government)? 

c)    How do we get a bottom up component in science?  Can we learn from the way businesses operate how to spread and develop new ideas from within the industry through networking and work groups? 

4)      A port by port survey of fishermen and fishing practices, somewhat along the lines of the U.S. Fish Commission survey of the 1880’s, should be considered simply to document the status of the industry.

5)      We ought to consider forming a group of ‘zone historians’ who would summarize once each year – perhaps in a Department of Marine Resources meeting – significant developments in the lobster, other fisheries, suppliers, etc. in their zone.  Publish the summaries on the web.  Use this approach to give the State some inkling of developments it should know about but that it might otherwise miss.

 
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