Fisheries are a global resource,
exploited by many different nations with varying levels of effort, monitoring,
controls, and success in ensuring both biologic and economic sustainability. National agreements, as well as regional and localized
management, are ways in which countries attempt to protect their fisheries for
current and future harvesting. Despite their economic and environmental value
fisheries, particularly in industrialized nations, are often poorly managed,
monitored, and fished unsustainably. Many of the world’s fish stocks have been overfished, and others appear to be heading towards similar
depletions1. A study of 230 different marine fish populations found
a median 83 percent reduction in breeding population size from know historic
levels2. Today’s large consumer species stocks are also much
lower than historical levels3. There have been surprising findings
that typically, industrialized fisheries are in worse condition then
non-industrialized fisheries. A 2003 study found that stock biomass is often
reduced by 80 percent within the first 15 years of industrialized fishing, and
the remaining biomass is typically around 10 percent of pre-industrialization
levels4. Examples which are often cited when demonstrating this
trend are the Cod and groundfish collapses in the northern
Proper management should be effective at correcting declining fish stocks however fisheries failures still occur with alarming regularity. Fisheries are a complex issue, and although scientists and policy makers understand how single stocks function they may not understand the more complex dynamics of entire fisheries and how they respond to industrialized explotation4. To further exacerbate the complexity of fisheries management, scientific monitoring of fisheries often does not take place until after the stock reductions occur4. Once management strategies are finally enacted industrialized fishing has often been underway several years, resulting in attempts to stabilize fish stocks at already depleted biomass levels4.
The majority of fisheries legislation occurs intra-state or in agreements among several nations rather then as global initiatives and internationally binding laws. This said, there have been treaties ratified into law which affects national fisheries.
The most significant international policy which has influenced how nations manage their fisheries has been the United Nations Convention on the Law of the Sea (UNCLOS). UNCLOS deals with many different facets of the marine environment. Part five in particular has important ramifications for national fisheries. It addresses the creation and limits of individual nation’s exclusive economic zone (EEZ). Under article 56 states are granted “sovereign rights for the purpose of exploring and exploiting, conserving and managing the natural resources, whether living or non-living… [in waters extending no more than] 200 nautical miles from the baselines from which the breadth of the territorial sea is measured”6. Through this declaration, states assume control over any fish stocks which occur within 200 nautical miles of their shores rather than having international regulations regarding how all fish stocks should be managed. The living resources of the EEZ are managed “taking into account the best scientific evidence available to [the resource… by which the state] shall ensure through proper conservation and management measures that the maintenance of the living resources in the exclusive economic zone is not endangered by over-exploitation” as per articles 61 and 626. In article 64 UNCLOS addresses fish stocks which are not confined to one nation’s EEZ stating that the burden of managing straddling and highly migratory species falls on the “concerned parties”, and these parties must create a policy they can both agree on6. The status of migratory and straddling fish stocks was reevaluated and adjusted in 1995 through the implementation of a new agreement which built on the existing UNCLOS declarations in article 647.
Pre-industrialization fisheries had a significantly different role than they do today. Historically fisheries were viewed as a common area with open access granted to all, although there were some forms of management, particularly of costal resources, based on explicit fishing rights similar to conventional property rights which was overseen by a local regulatory board10. In utilizing the fisheries as a commons resource, rationale would dictate that individuals exploit it for every possible unit to be gained, despite the fish stock being a limited commodity – creating a situation which Garrett Hardin identified as “the tragedy of the commons”11. Many of the effects of a commons type resource were negated due in part to artisanal fishing methods and the fact that fisheries managed using traditional knowledge were usually sustainable10. The world’s population has grown rapidly over the past centuries, and historically smaller populations meant demand for marine resources was driven by local needs rather than large market forces10.
There is a historical lack of data collection in many fisheries which continues through the present10. In the past stock sizes were not areas of major concern, so data collection for stock population estimates was rarely carried out. Although some of the failure to collect data was due to scientific limitations of the time, much of the failure lies with past ideological views of the environment and natural resources as inexhaustible, existing primarily for mankind’s exploitation12.
Finally, as with any industry, as time advances technology improves10. Fishing vessels have become larger and more seaworthy, as well as cheaper and easier to build. Vessel propulsion moved from sails to internal combustion engines which require fewer individuals to operate and created larger profits for individuals engaged in fishing. Gear developments created lower maintenance gear which lasted longer and resulted in more efficient harvesting of fish. An especially large technological advance was the ability to move fresh seafood further and more efficiently using ice or live transportation rather then canning or salting the catch.
Today many fisheries are still managed under a limited commons type of system in which access to entry may be regulated and controls of fishing effort may be in place – especially in industrialized nations10. Commonly used controls include gear restrictions and quotas10. Many of the fisherman in this commons system display what is considered a rational response to the limits placed on them by attempting to take the maximum amount of fish they can remove from the water, even though they may be at odds with traditional and scientific knowledge13. Finally, as with any commons system, there is always the concern of individuals receiving a free ride though failure to follow the established rules13.
Another facet of modern fisheries management which is playing an increasingly larger role is scientists and policy makers being asked to manage multi-species relationships as well as entire ecosystems, despite limited understanding of population dynamics for single species of fish10. The difficulty of this task is further compounded when one takes into account that modern fisheries are not necessarily managed within community boundaries nor within ecosystem boundaries but rather on large scale political maps5. This may create “complex and often conflicting socio-economic issues” which may present conflicting objectives with scientific goals and knowledge10. Other modern concerns of fisheries include the loss of biodiversity, loss of stock biomass, and reduced recruitment rates.
As illustrated in Table 1 and Table 2 the North American lobster (Homarus americanus, henceforth referred to as lobster) is the dominant
There are two major families of
lobster worldwide. Clawed lobsters, such as Homarus americanus, are in the family Nephropidae, which is
composed of around 30 species. The other family of lobsters is Palinuridae which is comprised of clawless lobsters and
contains around 45 different species. Palinuridae
tend to be a warmer water species then Nephropidae. Clawed
lobsters are preferred by consumers over clawless lobsters because the meat in
the claws is softer, and because there is more body edible mass on same sized
individuals of the different families. Clawless lobsters are traditionally sold
as lobster tails, shredded lobster, and are used at some restaurants such as
Red Lobster. It is generally accepted that Homarus americanus can live past one hundred
years. Maximum recorded body weights have been in the high thirty pound range,
although the most common weight of commercial lobsters is in the pound and a half
to two pound range (three and a half to four inch carapace length)18.
Historically, lobsters were so
One of the strengths of
Technological changes also impacted
Despite the current prosperity of the lobster industry, there is already concern over what factors may be driving the surge in landings, and what effect this could be having on the ecosystem. Many reports demonstrate that the success of the lobster and similar fisheries to failures of higher trophic level fisheries1-5,10,16. There is a growing concern that the trends of the lobster industry indicate an ecosystem which is out of natural balance, and could potentially be proceeding down the same path as the cod and groundfish industries before it3,16. As oceans warm, diseases and predators may advance further northward to impact lobster stocks16.
The following indicators attempt to examine the health of
Once a species has crashed it rarely undergoes a rapid recovery. Most crashed fisheries exhibit little to no change in species abundance even fifteen years after the actual decline, as seen in Figure 12. The decline and resulting low landings are due to reduced reproducing populations and subsequently lower recruitment rates of juveniles. Individual species fecundity may also play a role in the lack of recovery as well as individual species fecundity to growth dynamics2,26,27. Lobster recruitment rates are at a historical high, which has been attributed to the extended period of predatory fish absence.
The trends indicated by Figure 1
serve as a caution to
Fish population dynamics is a
complex topic in which errors can and will occur. Most major fisheries have some type of data regarding
expected stock size in relation to how many fish are being removed from the
environment each year. This does not hold true to
mid to late 1990’s there has been a noticeable decrease in the total pounds of
lobsters caught in four out of the seven north Atlantic lobster fisheries
(Figure 2). In most situations, the decrease was a rapid occurrence, taking
less then five years for landings to drop to less than half of their peak value.
A factor often credited for
collapses is disease16. While disease may have played an assisting
role in fisheries collapse they could not have accounted for the entire decline
in catch. All of the fisheries dealt with the same species of lobster. This
leads one to expect that such a devastating disease would have spread quickly
with minimal regard for political boundaries – similar to how the long-spined
sea urchin (Diadema antillarum)
die off in the
A second possible explanation for the trends is a lack of
understanding of lobster population dynamics complicating management. It is
possible in fisheries with high depletion rates that localized extinction can
occur despite close monitoring – particularly for species which have late ages
of maturity such as lobster4. This coupled with the fact that size
selective fisheries such as lobster lose 80 percent of their of their adult
population each year may have resulted in a loss of a viable reproducing stock2,28.
The historical trends of northeastern lobster fisheries
indicate that despite its apparent success,
All of the protection on legal sized
lobster is geared towards conserving the females. Through these protections,
one would expect that the oversized lobster population will be skewed heavily
towards females. The issue which arises is that lobster mating is size
dependent, and although neither male nor female are monogamous there may be a
shortage of mating males15,22. The first
step which should be undertaken is to determine the actual ratio of oversized
male lobsters to females.
Lobstermen should also be encouraged to record the number of female lobsters that they V-notch throughout the season. This figure used in conjunction with the total number of lobsters captured will provide an idea of how much of the annual stock is composed of reproducing females. As these females progress to oversized lobsters the population ratio will become more accurate.
Research should be funded to determine how many females a male lobster will mate with given natural conditions in a two year period to determine the optimum amount of male lobsters to female lobsters. Comparing this result to the ratio established though V-notching and oversized recording will allow policy makers to quickly see if more male lobsters need to be protected. Once these ratios are established, if male populations are too low corrections can be made by setting a quota of male lobsters need to be V-notched. These regulations would not place any cost burden on the lobster fisherman and will potentially increase their annual catch in the long run.
Despite the moderately stable number
of licenses issued, the total landed pounds has been increasing steadily, and despite
a static license total the potential effort in the industry has been steadily
increasing. This phenomenon was documented in the Canadian lobster fishery as
well5. The correlation between individuals in the fishery and the
pounds landed is strong over the period data is available for. Increasing the
number of fisherman by 63 percent increased the pounds caught by 52 percent, or
increasing the fisherman by a multiple of 1.6 increased the pounds of fish
caught by a multiple of 1.9. The increase of effort is a result of a new
licensing scheme which was enacted in 1990.
Through limiting license types,
2. Hutchings, J. A. & Reynolds, J. D. Marine Fish Population Collapses: Consequences for Recovery and Extinction Risk. Biological Science 54, 297-309 (2004).
3. Jackson, J. B. C. et al. Historical Overfishing and the Recent Collapse of Costal Ecosystems. Science 293, 692-639 (2001).
4. Myers, R. A. & Worm, B. Rapid worldwide depletion of predatory fish communities. Nature 423, 280-283 (2003).
5. Charles, A. T. Fisheries management in Atlantic Canada. Ocean and Coastal Management 35, 101-119 (1997).
6. United Nations. United Nations Convention on the Law of the Sea. (1982).
7. United Nations. Agreement for the Implementation of the Provisions of the United Nations Convention on the Law of the Sea of 10 December 1982 Relating to the Conservation and Management of Straddling Fish Stocks and Highly Migratory Fish Stocks. 1-40 (1995).
8. Magnuson-Stevens Fisheries Conservation and Management Act. (1996).
Marine Fisheries Service. NOAA Fisheries Feature: Legislation. www.nmfs.noaa.gov/legislation.htm accessed
10. Caddy, J. F. & Cochrane, K. L. A review of fisheries management past and present and some future perspectives for the third millennium. Ocean and Coastal Management 44, 653-682 (2001).
11. Hardin, G. The Tragedy of the Commons. Science 162, 1243-1248 (1968).
12. Anderson, N. & Herst, B. personal communication. (2004).
13. Gavaris, S. Population stewardship rights: decentralized management through explicit accounting of the value of uncaught fish. Canadian Journal of Fisheries and Aquatic Science 53, 1683-1692 (1996).
14. Maine Department of Marine Resources. Preliminary 2003
15. MacDonald, B. personal communication. (2004).
M. Tracking Maine's Crustacean Bounty.
17. National Marine Fisheries Service. Landings Database. (2004).
of Maine Aquarium. A Lobsters Life. http://octopus.gma.org/lobsters/society.html
19. Maine Department of Marine Resources. Maine Department
of Marine Resource Strategic Plan. www.maine.gov/dmr/organization.html
20. Maine Department of Marine Resources. Lobster and Crab Fishing Licenses. (2003).
of Maine Aquarium. Lobstering History. http://octopus.gma.org/lobsters/allaboutlobsters/lobsterhistory.html
22. Mills, D. personal communication. (2004).
23. Maine Department of Marine Resources. Maine Department
of Marine Resources. http://www.maine.gov/dmr/commercialfishing/comfishlandings.htm
24. Holt, H. personal communication. (2004).
25. Pauly, D., Christensen, V. & Dalsgaard, J. Fishing down marine food webs. Oceanographic Literature Review (1998).
26. Rhode Island Division of Fish and Wildlife Marine Fisheries. Management Plan for the Crustacean Fishery Sector. 1-13 (2003).
27. Maine Department of Marine Resources. Maine Department of Resources research priorities for lobsters. (2004).
28. Rhode Island Division of Fish and Wildlife. Rhode Island Fisheries Stock Status: an overview. (2004).
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