Fishery Management Techniques, A Review

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					             NOAA Technical Memorandum NMFS-F/NEC-4

            ThiS TM series is used for documentation and timely commumcahon of
            preliminary results, interim reports. or special purpose information. and
            has not received complete formal review, editorial control, or detailed

                    Northeast ,-ishery Managemen t
                                    Task Force

        Fishery Management Techniques,
                   A Review

           Michael P. Sissenwine and James E. Kirkley

Woods Hole Laboratory, National Marine Fisheries Service, Woods Hole, MA 02543

                   U.S. DEPARTMENT OF COMMERCE
                   Philip M. Klutzolck. Secretary
                   National Oceanic and AtmospheJic Administration
                   Richard A. Frank, Administrator
                   National Marine Fisheries Service
                   Terry L. Lenzell, Assistant Administrator for   Fisherl~5

                   Northeast Fisheries Center
                   Woods Hole, Massachusetts

                                     October 1980
     This document is the result of studies originating within the ~orth­
east Fishery Management Task Force. The Task Force, organized in 1979
by the New England and :vIid-Atlantic Fishery Management Councils and
funded by the NMFS, seeks to promote discussion and dialogue on the
major issues of fishery management and to explore the effects of various
fishery management alternatives.

     Composed of representatives from the fishing industry, Regional
Fishery :vIanagement Councils, federal and state agencies, academic in-
stitutions, and general public, the Task Force will operate in three phases.
The first phase will assemble background information for identifying and
analyzing management options. The second phase will examine this
background information to determine the data requirements, regulatory
measures, administrative procedures, and enforcement methods
associated with each management option. The third phase will critically
review the various options for application to specific fisheries, particularly
the Atlantic demersal finfish fishery.

     This document is one of eight developed under Phase I operations,
all of which are being issued in the NOAA Technical A1emorandum
NlvlFS-F/NEC series. This document and six others functionally serve as
appendixes to the eighth and leading document for Phase I operations-
"Overview Document of the :-Iortheast Fishery :.'v1anagement Task Force,
Phase 1."

                    Jon A. Gibson, Coordinator
                    NOAA Technical 1\1emorandum .Vl\1FS-F/ NEC series
                TABLE OF CONTENTS
Introduction ..................................................... 1
Criteria for Evaluating Fishery Management Techniques .............. 1
Regulations Applied to the Harvesting Sector Associated with
   the Control of Fishing Mortality and Other Biological Impacts ........ 3
SociOeCU11 ('nl ic Methods for Influencing Fishing Effort ................. 6
tvlet hods of Allocating Catch or Benefits ............................. 8
Summary ....................................................... 10
Acknowledgment ................................................ 10
                 INTRODUCTION                                   more specific criteria which are usually relevant to selec-
                                                                tion of a management technique.
   There is a variety of methods available for the
management of fisheries. In each case, the optimal set of       1) Relationship of the fishery management technique
fishery management techniques will depend on the                to the control of fishing mortality: The linkage
objectives of management, the legal authority of the            between the resource sector and socioeconomic sector of
managers and the information base (scientific and               the fishery system is fishing mortality. This is the rate
otherwise) supporting management. Nevertheless, there           (proportion of the population per unit time) at which
are some inherent characteristics associated with each          fish are IPmoved as a result of fi"hing. Thus. man's abili·
technique of fisheries management which are relevant to         ty to accomplish objectives related to the condition of
the application of the method in general. This paper is         the resource depends on controlling fishing mortality.
intended to stimulate discussion and consideration of           Fishing and natural mortality (all causes of death other
these characteristics so that better-informed decisions         than fishing) act to reduce the size of the resource while
will be made in the future.                                     growth and recruitment (rate at which young fish are
   It is often said that "fisheries managers manage             added to the exploited component of the resource), act to
fishermen not fish." While fisheries management is              increase it. The secondary impact of fishing mortality on
usually applied directly to harvesters in the form of           growth, natural mortality, and recruitment as a result of
regulations, there are forms of management which are            its influence on the size and structure of the resource, is
applicable to other components of the socioeconomic             usually known only qualitatively. ~evertheless, the
sector; these may be non-regulatory in nature. Further-         potential of these secondary impacts is of concern in the
more. while fishery managers cannot "regulate fish,"            evaluation of fishery management decisions.
there are some forms of fishery management which have              The linkage between the resource and the
a direct and predictable impact on fish populations,            socioeconomic sector is described by the following
although the impact of some other forms is more closely         equations:
related to the socioeconomic sector.
   In the discussion that follows, fishery management                         F = qf                                        (1)
techniques which are applied to harvesters and other
comT)onents of the socioeconomic sector are considered.
The expected biological and socioeconomic consequence
of each technique is discussed. Several criteria for                                                                        (2)
evaluating fishery management techniques are also
   In addition to the methods of fisheries management           where F is instantaneous fishing mortality rate,
discussed in this paper, there are other methods used to
improve the condition of the resource independent of the          Z is instantaneous total (fishing and natural)
fishery. Resource improvement methods include habitat                  mortality rate.
protection and stocking. For some anadromous species of           N is population size in numbers,
inshore fisheries. resource improvement methods may be            f is the rate of expenditure of standard units of
vital to sustaining a viable fishery. For fisheries                    fishing effort,
significantly affected by human activity other than               q is a constant called the catchability coefficient,
fishing, such methods should be seriously considered.             C is catch in numbers,
                                                                  t is time, and
  CRITERIA FOR EVALUATING FISHERY                                 e the natural number 2.71828 ...

     MANAGElVIENT TECHNIQUES                                       These are fundamental equations of fisheries science.
                                                                The reader is referred to Ricker* for a detailed discussion
  \...'ltimately, fishery management techniques must be         of their application. Equations (1) and (2) are in·
evaluated against the objectives of management, Com-            troduced here to establish the direct relationship
parison of benefits (short- and long,term) associated
with the application of a management technique with             "Ricker. W. E. 1975, Computation and interpretation of
benefits which would accrue without management is in-           biological statistics of fish populations. Bull. Fish. Res. Bd.
herent in the evaluation process. There are several other       Can. 119. 300 pp.

between fishmg effor: and fishing mortality. and catch              processes which act to compensate for or buffer against
and fishing mortalit\', Clearly. these equations are perti-         perturbations. and the socioeconomic interrelationships
nent to the e\'aluation of the relationship between a               between fishing activity (commercial or recreational)
fisheries management technique and its control of                   and the activities of related industries and markets.
fishing mortality, Equations (11 and (21 will be discussed          Fisheries management techniques should reinforce the
further when considering specific management                        functioning of these other mechanisms, not interfere
technIque",                                                         with them,
    Fishing effort is a function of the amount of fishing
                                                                    4) Relationship of fishery management techniques to
gear and the amount of time the gear is used, If only one
                                                                    harvesting efficiency: There are many ways of
type of gear is used (all units of gear assumed to be of
                                                                    expressing the efficiency of fishing activity. It may be
equal efficiency') and fishing practices are relatively
                                                                    expressed in terms of the proportion of total potential
standard, then fishing effort is equivalent to the total
                                                                    productivity of the resource (short- and/or long-term)
amount of time spent fishing. When a variety of types of
                                                                    actually utilized. the cost per unit of catch, the cost per
fishing gear or fishing practices is used, then fishing ef-
                                                                    unit of fishing mortality generated by fishing, the total
fort is an additi\'e combination of the amount of time
                                                                    income generated per unit of catch. or value of catch per
spent fishing with each gear type or fishing practice,
                                                                    unit of energy (fossil fuel) used. to give some examples.
Coefficients for each term of this combination are used
                                                                    The specific measure of efficiency applicable to a par-
to account for differences in efficiency between types of
                                                                    ticular fisher:.' management plan depends on the objec-
fishing gear and fishing practices, Thus. the amount of
                                                                    tives of the plan. Hoviever it is defined. the effect of a
time spent at one type of fishing is expressed in terms of
                                                                    management technique on efficiency is an important
the amount of time spent at another type of fishing
                                                                    criterion for evaluating that technique.
(defined as the standard) which results in the same
fishing mortality rate. Clearly, effort has many com-               5) Historical precedent for application of the fishery
ponents: the amount of gear. the type of gear, how much             management technique: In some cases, success of a
it is fished, and how it is fished.                                 fisher:.' management plan will depend on its credibility
                                                                    with those managed and \"'jth society in general.
 2) Relationship of fisheries management techniques                 Therefore, past perceived successes or failures of par-
 to other biological impacts: Fisheries management ac-              ticular fishery management techniques should be con-
 tions may have more specific biological imlJacts than              sidered. The lack of historical precedent for a particular
 control of fishing mortality, Some fishery management              approach is not necessarily a disadvantage when no pop-
 tec hniques are effecti\'e in restricting the impact of            ular alternatives are avaiJable.
'fishing on specific components of the resource. For
 example. the techniques may be intended to protect                 6) Relationship of the fishery management technique
 small fish. spawning: fish, or fish of a particular species.       to cost of enforcement and administration: The net
 Such biological objectives are usually related to implicit         benefit of fishery management (over that which would
 socioeconomic objecti\'es, for instance, the assumption            accrue in its absence) must include the cost of ad-
 that protecting small fish will increase yield per recruit         ministering and enforcing the management programs.
 (and revenues); the assumption that protecting spawn-              Some fisheries management techniques are inherently
 ing fish will increase the probability of a good recruit-          more difficult (and costlyl to administer and enforce
 ment and future producti\'ity (and revenues): and the              than others.
 assumption that total benefits will be increased by                7) The relationship of the fishery management
 protecting a particular !'-pecies from one user group              technique to non-target components of the fishery
 (foreign fishing for example) in favor of another                  system: Biological, economic and social objectives of
 (domestic fishery).                                                fi;ohery management are often specific to particular com-
                                                                    ponents of the fislw;-y "y:,1 em. e.g., a particular ~ j)e(jps. a
:1) Relationship uf management action to the natuntl
                                                                    particular user group or a pdfticular processing segment
functioning of the fishery system: The ability of
                                                                    of the industry. While a fisheries management technique
fishery managers to influence the future state of the
                                                                    may be appropriate for a set of specific objectives, the
resource is limited, Total productivity of the system is
                                                                    impact of its application on non-target components of
ultimately determined by such factors as incident solar
                                                                    the resource should be considered. In the case of species-
radiation and available nutrients, not by fisheries
                                                                    specific biological objectives, the effect of management
management. Fishery managers are more capable of in-
                                                                    actions on the capacity of the harvesting, processing. or
fluencing the structure (species and age distribution) of
                                                                    related sectors to redirect attention to other components
the system. but even this ability is limited. Thus. in
                                                                    of the resource is particularly important.
e\'aluating fishery management techniques, the
reasonableness of the goals that the techniques are in-             8) Relationship of the fishery management technique
tended to accomplish should be considered.                          to its scientific basis: The specific application of a
   Fisheries management serves as an artificial form of             management technique is usually based on scientific
control of system dynamics. There are other mechanisms              consideration of the expected short- and/or long-term
which stabilize the system. such as the natural biological          impact of the action. The cost and feasibility of

developing a scientific basis for the action varies, de-            (2), population size must be estimated. Thus, the deter-
pending on the technique used and the acceptable level             mination of the desired catch restriction is strongly
of risk that objectives will not be achieved. Furthermore,         dependent on the accuracy and precision of assessments
the robustness of the technique relative to its scientific         of the status of the resource. Catch regulation is scien-
basis also varies. To put this another way, given a vague          tifically a very demanding form of fishery management.
or imprecise scientific basis for action, some techniques          It is not robust with respect to its scientific basis. The
will nevertheless tend to serve the objectives of manage-          following example should clarify this point.
ment while others might suffer in effectiveness.                      Assume that the optimum fishing mortality rate is
                                                                   known, and that the fishing fleet is of an appropriate size
      REGULATIO~S    APPLIED TO THE                                to generate this amount of fishing mortality on a con-
   HARVESTING SECTOR ASSOCIATED                                    tinuing basis. Suppose further that the fishery is
                                                                   managed by an overall annual catch quota and that the
    \VITH THE CONTROL OF FISHING                                   size of the resource is underestimated by 25%; it will
  MORTALITY AND OTHER BIOLOGICAL                                   become necessary to close the fishery for the last three
               I:'v1PACTS                                          months of the year, Such a closure might have a severe
                                                                   adverse social, economic, and political impact as well as
   Fi"     L:,,;Ui:··:Lt'I'~ actions are ldliLlly in thp form of   resulting in a suboptimum fishing mortalit,\ rate. On the
regulations         ied to the han'esting sector. These            other hand, suppose that the stock is overestimated by
regulations are intended either to produce a direct                25o/c; this also will result in suboptimal fishing mortality
biological impact on the resource or to influence the dis-         and possibly in some long-term adverse social, economic
tribution of benefits between users or user groups. The            and political impacts. In most cases, the precision of
former type of harvester regulation is discussed in this           stock assessments is such that 25CC errors in estimates of
section.                                                           stock size will occur routinely.
   As indicated by Equations (1) and (2) in Part 1 of the             Catch regulations designed to accomplish a specific
previous section, catch and fishing effort are directly            fishing mortality rate not only require accurate and
related to fishing mortality. Thus, restrictions on catch          precise information on the size of the resource, but that
and/or fishing effort are appropriate fishery manage-              this information and the regulations based on it be
ment techniques for "active" or direct attempts at con-            almost continuously updated. When the condition of the
trolling fishing mortality (and accordingly, the short-            resource changes rapidly relative to the time required for
term and potentially long-term dynamics of the                     collection and analysis of scientific data and revision of
resourcel. The relationship of active or direct fishery            management regulations, it may be impractical to
management techniques to fishing mortality is described            adjust regulations quickly enough to respond to the con-
by a simple function of socioeconomic variables specified          dition of the resource.
in the regulation. Other common fishery management                    The application of catch regulations is further com-
techniques which regulate the harvesting sector may be             plicated for mixed fisheries (where more than one species
termed "passive" since these methods do not directly               is captured by il. unit of fishing effort). It may be impossi-
relate (by simple functions of socioeconomic variables             ble to achieve the desired fishing mortality for one
specified in the regulation) to fishing mortality although         species without exceeding the desired mortality for
they usually have some indirect effect. Spatial and tem-           another. For two species which are closely associated in
poral restrictions on fishing activity, restrictions on            trawl catches (cod and haddock on Georges Bank, for
fishing gear. and restrictions on the nature of catch (as          example), catch regulations which produce significantly
opposed to the amount) are examples of such passive (or            different fishing mortalities for each species may result
indirect) management techniques. The effect of such                in early closure of fishing for one of them followed by
techniques on fishing mortality cannot be explicitly es-           wasteful discarding of catch which cannot be legally
timated; where effort and catch are unregulated, fishing           landed and sold. The mixed-fishery problem may in
mortality remains theoretically unbounded.                         some cases be mitigated by gear and/or spatial-temporal
   Passive methods of regulation affect components of              regulations (discussed below)' There are also analytical
fishing effort (type of gear used, fishing practices) but          methods for designing an optimal set of species-specific
other components are not controlled (the extent to which           catch regulations for a mixed fishery (linear program-
each type of fishing gear and practices may be used),              ming for example), but the regulations may be subop-
thus the resulting mortality is not explicitly known.              timal with respect to a subset of the species.
These two types of fishery management techniques
                                                                      Catch regulations may also be applied passively
regulating the activity of the harvesting sector are dis-
                                                                   (without direct consideration of the associated fishing
cussed below, with reference to the evaluation criteria
                                                                   mortality), For a developing fishery where data and
proposed in the previous section.
                                                                   analvsis are minimal, the catch may be restricted as a
Active Regulation: An overall restriction on total catch           prec~ution. to prevent fishing mortality from becoming
(during a specific time period) may be used to achieve a           excessive !this is referred to as a preemptive quota). This
desired fishing mortality rate. In order to determine the          form of regulation is most acceptable for resources which
appropriate restriction on total catch based on Equation           are not in high demand. Thus, the potential short-term
loss of benefit" associated with such a conservative                     regulation. not as a basis for continuous updating of
strategy rna:,; be minor. Ob\-iously, where demand for a                 regulations, Furthermore. there is evidence that fishery
resource is low, a more conservative strategy may be                     resources during periods of low productivity are less
used to reduce the amount of stock assessment informa-                   susceptible to severe reductions in biomass when they
tion necessary to support management decisions,                          are regulated by a constant fishing mortality (effort)
   The relationship of catch restrictioll!3 to biological im-            strategy than by a constant catch strategy. Unfortunate-
pacts other than fishing mortality iE usually unknown,                   ly. fishing effort (in units proportional to fishing mortali-
V;here catch is. restricted for a group of species about                 ty) is difficult to measure. It has many components.
equally vulnerable to exploitation. the most valuable                    Furthermore. the relationship between nominal fishing
species is likely to be caught most; thus. the species com-              effort (raw data before standardization I and fishing mor-
position of the resource may change, Catch restrictions.                 tality changes when fishing practices and gear change.
which cause a change in the size and composition of the                  Therefore, an iterative approach to determine the ap-
resource may indirectly affect recruitment. natural mor-                 propriate fishing effort regulation might be necessary;-
tality. and growth, but usually such impacts can be fore-                possibly using historic data on fishing effort as a basis for
seen only qualitatively.                                                 selecting the starting point. Even a preliminary regula-
     In general. application of catch restrictions is com-               tion should be adequate to prevent long-term damage to
patib]e with the dynamics of the fishery system, Catch is                the resource without excessively sacrificing current
usually reduced during periods of low productivity of the                benefits. Trends in fishing mortality of the resource must
resource and increased when productivity is high, tend-                  be monitored. but it would not be necessary to modify
ing to stabilize the biological component of the system,                 fishing effort regulations routinely as is the case with
Cnfortunately, in some cases catch restrictions may                      catch regulations. Furthermore, changes would be
work to destabilize the system in the short term. This oc-               modest relative to those necessary with catch
curs when the scientific basis of the regulation is in error.            regulations. Vhth catch management, changes in regula-
When the resource is larger than anticipated, catch is                   tion are necessary in response to variability in produc-
restricted to unnecessarily low levels and the resource in-              tion of the resource. With effort regulation, changes are
creases. Howe\'er, when the resource is smaller than an-                 usual~y related to the socioeconomic st:ctor CJf the system
ticipated, catch may in effect be unrestricted, resulting                which is less variable.
in a further decline in abundance,                                          Fishing effort regulations are scientifically robust with
   There is substantial historical precedent for the                     respect to stock assessments. The fishing mortality
application of catch restrictions, which have been used                  associated with a particular effort regulation need not be
for the management of marine commercial fisheries                        known precisely so long as trends in abundance and
throughout the world. In general, the success achieved                   productivity of the resource can be monitored. The con-
through application of catch restrictions depends on the                 dition of the resource at any particular moment is of lit-
realism of the objectives they serve, and adequacy of the                tle importance since catch will respond to stock size
scientific basis for management action. In the case of                   automatically, given constant effort.
~ew England groundfish, fishery management objec-                           Catch and effort regulations will encourage each in-
tives have been unclear, and the level of precision of                   dividual harvester to maximize efficiency (catch per unit
"state-of-the-art stock assessments" has been un-                        cost of harvesting) unless catch is limited during each
satisfactory to those managing this highly-valued                        time unit of harvest. There is a potential for over-
resource. Therefore, application of catch restrictions for               capitalization where fisheries management is based on
l':ew England groundfish management under the                            catch or effort regulations and marginal profits are
auspices of FCMA has been controversial and generally                    adequate to attract more harvesters than necessary to
unsatisfactory, establishing a poor precedent for the                    utilize the available resource fully'. Since effort regula-
future,                                                                  tion applies to harvesting units, not part icular species
   p;:[\ 1)1' ,he diffic\llt~· associated with catch restrictim-,s        (as j;; the case with catch regulatiun,o,), :.ilf\esters are
em );e\\ England groundfish has been in law enforce-                     able to divert effort from one component of the resource
ment. Special problems arise when specific regulations                   to another, as they wish.
are applied to subunits of the resource, because catch                      Effort regulation has been applied to marine commer-
sources are hard to identify and relate to subunit catch                 cial fisheries less extensively than catch regulation. The
limits.                                                                   U.S.A. proposed effort regulations for the area off the
    Desired fishing mortality rates are more directly                     northeastern U.S.A. to the International Commission for
achieved by regulation of fishing effort than by regula-                  the ~orthwest Atlantic Fisheries (lCNAF) in the early
tion of catch. Fishing effort (when standardized to ap-                   19iO's, but the proposal was rejected. Since then. Canada
propriate units) is directly proportional to fishing mor-                 has applied effort regulation to inshore fisheries along its
tality rate [see Equation (1)). Therefore, once an ap-                    coast. Effort regulation has been applied to the ocean
propriate level of fishing effort is determined, this level               quahog and surf clam fisheries in the Mid-Atlantic
may be maintained without dependence on continuing                        Region. It is too early to judge the success of these
stock assessment. Stock assessments, in such a case,                      management actions. Fishing effort regulations are often
\\'ould be used to monitor the response of the resource to                associated with such forms of management as limited

entry or controlled access (these methods are discussed             fishing mortality, these regulations will have to be
in greater detail later). In some regions, this may cause           "tuned" routinely to offset changes in fishing intensity
opposition to effort regulation. In fact, limited entry or          and efficiency.
controlled access may be intended to allocate resources                The scientific bases probably already exist for spatial
among user groups, not necessarily to regulate fishing              and temporal restrictions on fishing aimed at protecting
mortality. Limited entry could be used to allocate the              components of the resource during particularly
resource to user groups within the framework of either ef-          vulnerable periods. For example, the areas and times of
fort or catch regulation,                                           spawning of many of the fishery resource species off the
                                                                    northeastern U.S.A. are known within reasonable limits.
                                                                    Furthermore, the areas and seasons during which
                                                                    recruiting fish are particularly vulnerable are usually
Passive Regulation: Passive techniques of fishery                   known too, from previous catch data and research survey
management are usually related to specific biological               data. Nevertheless, because of the mixed (multi-species)
impacts other than control of fishing mortality. Impact             fisheries of the region, spatial and temporal closures of a
of these passive methods on fishing mortality cannot be             fishing ground to protect one species may severely
analyzed by su,'h functional relationships as tho",=, :,hown        restrict fishing for Of her species. Further data on the
in Equations (IJ and I:':),                                         spatial and temp'lfnI di:"trilJLltiol1 of the reSOC:[C2S may
   Spatial and temporal restrictions on fishing are usual-          help to reduce any unnecessary impact of these restric-
ly imposed in order to protect a component of the                   tions on fishing, but the cost (perhaps are-occurring
resource, perhaps during a vulnerable period such as                cost) of gathering the additional information must be
spawning. For example, spatial and temporal restric-                compared to the potential benefits.
tions on fishing are in effect for the Georges Bank area in            Spatial and temporal restrictions on fishing are easily
order to protect spawning haddock. Since fishing activi-            administered. Cnless such restrictions apply on a fine
ty may disperse aggregations of fish necessary for                  scale, they are also easily enforced. Moreover, there is
breeding, spawning ground closures may increase the                 significant historical precedent for spatial and temporal
likelihood of successful reproduction. In some cases,               restrictions as management tools for marine fisheries.
spatial and temporal restrictions are intended to                   The virtue of protecting particular components of the
decrease by-catch of particular components of the                   resource (such as spawning fish or young fish) is widely
resource or to minimize the likelihood of conflicts                 accepted by both managers and harvesters. Spatial and
between user groups (i.e., gear types). Current restric-            temporal restrictions on fishing activity are often widely
tions on the allowable season and area for foreign fishing          supported by the fishing industry itself, notwithstanding
off the east coast of the Cnited States serve both these            the fact that the long-term potential benefits of such
purposes. Temporal and spatial restrictions on fishing              closures (particularly to protect spawning fish) are
may promote inefficiency, since they often result in                usually unknown.
fishing being carried out at times and places that yield a             Spatial and temporal restrictions reduce the flexibility
relatively low catch per unit of effort. Thus, some im-             of the harvesters. In some cases, such restrictions may
mediate cost is paid in the hope of future benefits (by             preclude development of a fishery for some component of
protecting spawning aggregations, for example). In the              the resource not addressed in the fisheries management
case of spawning-ground closures, long term benefits are            decision process. These regulations may also affect
usually known only vaguely.                                         (intentionally or unintentionally) the distribution of
   Spatial and temporal restrictions could be a means of            benefits between user groups.
reducing total mortality for the resource. This               Gear regulations are also imposed in order to reduce
could be accomplished by reducing the efficiency of each            fishing mortality on some particular components of the
unit of fishing gear (fishing power) or the total number of         resource. But again. since these regulations are not
fishing opportunities. The actual reduction in fishing              directly tied to fishing mortality by explicit functional
mortality resulting from any set of spatial and temporal            relationships (such as Equations (1) and (2)), gear
restrictions cannot be predicted explicitly, and it is for          regulations may be considered passive.
this reason that these regulations are classified as                   :vlesh regulations are among the most common tools of
passive or indirect. The appropriate set of spatial and             marine fishery management. By increasing the size of
temporal restrictions for achieving some desired reduc-             the codend mesh of a trawl, the fishing mortality in-
tion in fishing mortality must be determined iteratively.           flicted on young or small fish is reduced. Thus mesh
Spatial and temporal restrictions alone cannot impose a             regulations may be an effective means of advancing the
ceiling on fishing mortality (except for the trivial special        age at which fish are recruited to commercial fisheries,
case where no fishing is allowed), since reduced efficien-          resulting potentially in an increased yield per recruit
cy due to spatial and temporal restrictions may be offset           and/or an increased proportion of individuals of each
by improved technology or increased effort. The overall             cohort that survives to spawn, for a given level of fishing
impact of fishing reflects both the intensity of fishing ac-        effort.
tivity and its efficiency. Consequently, if temporal and               Gear regulations may be used to reduce undesirable
spatial restrictions are the sole means of regulating               by-catch. For example. regulations which restrict the use

of bottom trawls in the foreign squid fishery reduce the                    restrictions. the harvester is responsible for avoiding
 by-catch of demersal fish.                                                 specific components of the resource. ;";evertheless. some
   Gear restrictions may also be used to reduce overall                     unwanted fish may be caught and this catch may be dis-
fishing mortality. In such cases, gear restrictions act to                  carded at sea with some accompanying mortality. Even
reduce the efficiency of fishing for some species or some                   when harvesters can avoid restricted components of the
size groups. To the extent that gear efficiency and the                     resource. some unwanted catch (and wasteful discard-
amount of fishing effort expended with the regulation in                    ingl may occur because of the desire to catch other
place can be compared with gear efficiency and effort                       valuable components. For example. the capture of small
without regulation. the effect of gear restriction on                       haddock can be avoided by using larger-mesh trawl gear.
fishing mortality can be evaluated. However, as with                        but to do so may result in reduced catch rates of larger
temporal and spatial restrictions. the effect of gear                       haddock and some other species.
restrictions on fishing mortality will usually only be                         The benefits associated with gear restrictions, spatial-
known qualitatively. Gear restrictions in themselves are                    temporal restrictions and restrictions on the nature of
not capable of providing full control of fishing mortality.                 the catch tend to be species specific. Thus, it is necessary
The appropriate set of gear restrictions for ac-                            to consider the secondar~' impact of these fishery
complishing a desired fishing mortality would have to be                    management actions on other species. For example. a
determined iteratively. Where fishing effort and efficien-                  mesh regulation or spawning ground closure appropriate
cy have a significant potential for increase, tuning of the                 for one species may eliminate a fishery for another.
management system will require periodic assessment of
the status of the resource.                                                     SOCIOECONOMIC METHODS FOR
   There is considerable scientific knowledge about the
effectiveness of mesh regulations in reducing fishing
                                                                                 INFLUENCING FISHING EFFORT
mortality as a function of fish length. It is clear that                       In addition to active and passive methods for control
mesh selection is not very precise. That is, the mesh size                  of fishing mortality and the future state of the resource,
which allows most fish smaller than a particular size to                    management techniques directed at influencing the
escape will allow many fish larger than that size to es-                    socioeconomic sector of the system may be considered.
cape as well.                                                               The distinction between socioeconomic controls and ac-
   There are several appealing aspects of mesh                              tive and passive methods is found in the way in which
regulations. They should be relatively easy to enforce                      they attempt to control mortality or related components.
except where multi-species fisheries require more than                      All three approaches affect the socioeconomic system.
one codend on-board. as in New England. The optimal                         The socioeconomic methods attempt indirectly to con-
mesh regulation for protecting a component of the                           trol mortality by directly influencing the socioeconomic
fishery resource is relatively insensitive to the current                   system toward a desired state of the fishery; the active
condition of the resource. Therefore, management by                         and passive methods are more direct attempts at con-
mesh regulations may reduce the need for ongoing stock                      trolling mortality which indirectly influence the socio-
assessments. In fact. if the minimum mesh size were es-                     economic system.
tablished at a level that would allow "adequate oppor-                         Two techniques which can be used to influence fishing
tunity to spawn" prior to becoming vulnerable to the                        effort and mortality through the functioning of the
fishing gear, no further regulation is likely to be                         socioeconomic sector are incentive-disincentive plans
necessary from a conservation standpoint. But there is                      and price controls. These may be considered as
usually no scientific basis for determining the amount                      variations of taxation depending upon how they are im-
and quality of spawning opportunity which is adequate.                      plemented. Both techniques influence the ex-vessel
It is noteworthy that, for many fishery resources, post-                    price, and thus revenues, in order to discourage or en-
poning the age at first capture beyond tbe age of first                     courage the han'esting of a particular species.
spawni .:.; ;I:,,\l:\~ in an increased yield pl::~ r'(r1lit. l'r;for-          Tnn;nti\'t;-disi:Jcenti"e plans attempt to rec1irect
temlt , J1wsh se!ection is species specil:c. Tlwrefore,                     vessels and harwsting from one species to another,
the oj)timal mesh size for a mixed species fishery will be                  making the price of the first species less attractive <the
based on compromise.                                                        disincentive) than the price of the second (the incen-
   Restrictions on the nature of the catch are sometimes                    tive L The incentive is financed by a system of pooled
a means of accomplishing the same biological objectives                     landings fees. This approach has often been termed a
toward which gear or spatial-temporal restrictions are                      landings fee scheme, a taxation scheme, or a subsidy
directed. Gear restriction and spatial-temporal restric-                    program. Price controls also can function as an
tions may be designed to pre\'ent capture of small fish or                  incentive-disincentive plan by establishing a regulated
fish of a particular species. As an alternative to these                    ceiling price on the more desired species and minimum
methods or in conjunction with them, the nature of the                      prices on the less desired species. However, price con-
catcb may be regelated directly (minimum size regula-                       trols, unlike the incentive-disincentive plan, do not in-
tion or restriction on the taking or landing of specific                    clude a mechanism whereby pooled funds can be used to
species). When the nature of the catch is regulated                         make the prices of the underutilized species more attrac-
without accompanying gear and spatial-temporal                              tive to harvesters.· Moreover, price controls interfere

more directly in the market-established price because         on harvesting costs which is not generally available, and
they directly affect not only the prices received by fish-    extensive information on stocks. This approach would
ermen, but also the prices paid by processors/whole-          probably be costly in terms of monitoring and ad·
salers to the harvester. The incentive-disincentive plan      ministration. Ho~ever. the program, combined with
attempts to affect only the prices received ex-vessel, and    other fishery management techniques, could be
thus higher market level prices should not be affected        beneficial. It would save waste from discards.
except by conventional market demand and supply               Technological innovation, often assumed to remain the
phenomena.                                                    same under many other regulatory approaches, would
   Since the incentive-disincentive plan has actually         not be discouraged. Importantly, effort and therefore
been considered as a possible management approach for         fishing mortality would be reduced on the overfished
groundfish in the northeast and since price controls          species.
operate in a similar manner, a discussion of the                 As noted above, in principle, price controls work to in-
economics and problems of the incentive-disincentive          fluence fishing effort and fishing mortality in a manner
plan is presented for illustration. As already stated, this   similar to an incentive-disincentive program. However,
approach attempts to make the price of the overfished         price controls are potentially an alternative to species-
I however this is defined) species less attractive than the   specific catch or effort regulRtions whrre price is highly
       of the underutilized species hy directly inEuencing    i1",\ihle. If pricr were he:'! l'()!\"tan~ (independent of
returns to fishermen by mean:; of a pool of funds created     supply). then the incentive co ha:Tesl a resource would
by the landings fees. The relative difference in prices in-   decrease as ahundance decreased. Thus negative feed·
fluences the harvesting activities by redirecting effort      back between fishing effort and resource condition would
from the overfished species to the underutilized species.     be established or reinforced, tending toward stability' in
   The effectiveness of the incentive-disincentive plan is    the system.
predicated on its acceptance by industry and by the              Price controls intended to inf1.uence fishing mortality
ability of management to incorporate changes in the           via the functioning of the socioeconomic sector could be
bioeconomic environment into the plan. That is.               imposed at the harvester, processor, wholesaler, or
management must constantly monitor such changes in            retailer level. Price con trois at higher market levels
order for the incentive-disincentive components to be         would affect the derived demand for fish and related
determined. This approach, like other regulatory or           products at all lower market levels, e.g., a price control
management techniques. must be established in accor-          at the retail level would affect not only the consumers
dance with a goal or set of objectives which explicitly or    demand at the retail level but also the retailer's demand
implicitly sets some desired level of catch and/or effort.    from wholesalers and the wholesaler's/processor's de-
   However, of far greater importance to the viability of     mand from harvesters. The specific effects would, of
the incenti\'e-disincentive approach is the development       course, depend also on other factors such as market sub-
of markets for the less desired species. It is often uncer-   stitutability, relative product prices, and export poten-
tain how such markets will be developed. Currently.           tial. However, price controls could benefit consumers in
most commercially-viable, underutilized species are           the form of reduced prices, though shortages (or black
either foreign-caught or exported by the United States.       m1:1rkpts) for products in high demand could occur.
In order to sustain an expanded fishery for underutilized        Agriculture has had a long history of price controls,
species, domestic and/or foreign markets must be              and more especially, supports and/or loan programs.
developed, and the on-board quality-control, handling,        Most price support programs were based on the concept
and storage of the fish must be improved.                     of parity. the parity price being pegged to the price of
   Initially, such a program will require funds for its es-   some other products and fluctuating from time to time
tablishment. Federal funds could be used for 'seed'           with the price of those products. Such programs attempt
money or an initial endowment. However, the long-term         to provide a standard of living or minimum income,
sol vency of the fund is an important consideration in the    while ensuring an adequate supply of agricultural com-
development of such a plan. The cost and source of funds      modities and preventing soil depletion. :'vIany of the loan
for market development must also be considered.               programs were actually price- or income-support
   Almost all underutilized species are candidates for the    programs termed "non-recourse" loans. They resulted in
incentive-disincentive program. However, the more             payments made to producers when market prices fell
common species with respect to the northeast and mid-         below a specified percent of parity price. However, it
Atlantic areas inc:ude silver hake, mackereL squid.           should be realized that these programs were all poten-
dogfish, and butterfish.                                      tially directed at regulating the market price, and
   An incentive-disincentive plan presents certain prob-      thereby, affecting the allocation of goods and services.
lems. It requires an agency or group to administer it; it        It is unclear how these programs could be used to help
may lead to new entrants in the underutilized species         resolve the problems of managing the fisheries of the
fishery which may dissipate any gains in net benefits;        )iorthwest Atlantic. Fisheries problems are not the same
such a plan requires management to adjust constantly          as those in agriculture. :viany of the agricultural
the incentive-disincentive rates as either abundance or       problems resulted in the federal government buying and
market conditions change: it also requires information        storing commodities; fish commodities are not as easily
stored, In addition. there are still the marketing                    Trip iimit", ha\'e another :,>ocial impact which is dif,
problems for the underutilized species, Thus. further              ticult t(1 qUJ.nt ,The\' reduce the le\'e; oj competition
study is needed before serious consideration is given to           in the !l:'>hll1~ profession, \\'ithoul trip iimits, the best
using any of the above-mentioned programs as a form or             han'P"ler" (hi~hlinersl gain the largest share of the
part of fisheries management.                                      henelits, \\'ith trip limits. the ad\'antage of being a
                                                                   high liner is reduced, and benefns are more e\'enl\' dis-
                                                                   tributed, Thl!" ma\' also prevent financial failures of
         11ETHODS OF ALLOCATING                                    ~()me han'esting operations and act to maintain m the
            CATCH OR BE:\EFITS                                     fishery some marginal unit!" (\,essels which are inefficient
                                                                   \'esse!" in t he absence of trip limits I, This latter concept
   In addition 10 influencing the future condition of the          illustrates the t\'pe of trade-off decisiom confronting
resource and the overall level of short and long-term              management. forcing managers to choose among
benefits. fisheries managemem also affects the alloca-             beneficiaries,
tion or distribution of benefits and income. The primary
fisheries management techniques used to allocate
                                                                   Vessel Allocations. Vessel allocatiom have certain
benefits are trip limits. vessel allocations, and
                                                                   effects similar to trip limits, Their primary purposes are
controlled-access schemes,
                                                                   to allocate catches in a manner that gives each vessel the
Trip Limits. These restrictions limit the catch of a               chance at a sufficient income. and to avoid closures
particular species or group of species on a per-trip basis.        when used in conjunction with quotas, However. vessel
usually expressed in the Korthwest Atlantic fisheries as           allocations are different from trip limits in that they
catch per-vessel-day or per-vessel-week. The purpose               generally do not restrict catch per unit effort. and thus
has been to distribute the total allowed catch over the            do not increase the minimum cost of catch per unit ef-
period during which it was intended to be caught.                  fort, provided additional vessels do not enter the fishery.
However. the use of trip limits has seldom prevented a             It is important to note that vessel allocations do not
fishery from being closed. In fact, the perceived                  necessarily restrict total harvest; they can be im-
economic impacts of trip limits low enough to prevent              plemented without an overall catch quota for the
closures (gi\'en the level of effort in the fishery) ha\'e         primary purpose of distributing income. However, if
often been so severe that it has been necessary for fishery        vessels enter the fishery in anticipation of profits and
managers to raise owrall quotas in order to increase trip          allocations remain the same, gross and net incomes per
limits,                                                            vessel will fall as a result of lower catches per unit effort
   Trip limits may haw an effect on the level and dis-             resulting from reduced stocks.
, nbution of gross and net incomes. That is. if catches per           A major problem with vessel allocations is how to
trip are constrained. total revenues may also be con-              determine the allocation. The use of prior catches results
strained, However. trip limits not only affect the income          in the same distribution of income as in the past. i.e.,
or revenue component. the:v also may affect the cost               those with lov'! incomes remain low while those with high
component;' this depends on how trip limits are im-                incomes remain high. ?\ew entrants must be controlled
plemented, If trip limits are used in accordance with an           or income per vessel will decrease either as a result of
owrall quota. and there are no constraints on the                  rt-duced stock size, or quotas used in conjunction with
number of trips. fishermen will attempt to increase their          the allocation system.
number of trips in order to harvest as much as possible               In the fisheries of the 1\ orthwest Atlantic, the deter-
before the overall quota results in a closure, This in-            mination of allocations is made more difficult as a result
creases the cost of harvesting on a per-unit harvest basis         of the multiple species nature of the groundfish fishery,
over time. The increased cost per unit harvested results           in which the primary species sought are cod, haddock,
in decreased net income or profit, and may eventually              and yellowtail flounder. In attempting to develop a
force the less efficient v0!'!'els (with respect to the trip       strateg~' for vPFsel a!l()catio;;" in a mixed fishery. Ii is
limit) out (if the fishery                                         necesskHY to consider an allocation for each specie!' in a
   Trip lImits are R method of allocation of income and            directed fishery and the associated by-catch fisheries.
benefits to harvesters and other user groups. If they are          This requires considerably more biological and economic
set in accordance with an overall quota, they may result           information if the allocation system is designed to deal
not only in a decrease in revenue per vesseL they may              with the problems of income distribution. In addition,
also increase harvesting costs, thus causing net benefits          the implementation of a vessel allocation system would
to society to decrease, However. more profound are the             require a substantially greater cost to set up and enforce.
potential impacts of trip limits and closed periods on                Vessel allocations, like many of the other methods
local communities. They may severely disrupt the                   already discussed, are dependent on biological data. It
economy of small coastal communities by creating                   would be of little value to implement a vessel allocation
seasonal unemplo~'ment where there are few, if any,                system for the sole purpose of distributing income. Thus,
alternative seasonal forms of employment. Such impacts             it may be reasonably assumed that its consideration
of management on local communities have sometimes                  would also be predicated on goals of stock management
been overlooked in implementing fishery plans.                     and conservation; this would require data on stocks and

abundance. Given this objective, utilization of a vessel             enter the fishery in an attempt to realize part. or all of
allocation sYstem would have to be extremely flexible to             that profit. However. their entry may result in increasing
adjust to changes in stock size and abundance as well as             the costs of production to the point where pure profit or
to changes in market conditions. In addition, a vessel               rent i!:i dissipated. and the number of vessels or units of
allocation system, if based on 'reasonable' management               effort coincide with the equilibrium between price and
criteria such as conservation, would in fact be a form of            average cost. This is the open access equilibrium in
controlled access. Only those vessels with allocations               which resources are misallocated, rent is zero, and net
would be allowed to exploit a particular species or                  benefits to society are not maximized.
species group.                                                          Since the open access fishery leads to the above
                                                                     problems, controls on entry or access have often been
 Controlled Access. Limited entry, controlled entry,                 recommended to prevent the dissipation of rent and/or
 licensing, stock certificates, vessel allocations, and taxa-        misallocation of resources by forcing some factor inputs
 tion are all forms of controlled access. All attempt to             into more productive alternatives. The primary gain to
 limit the level of effort either directly or indirectly, or         he expected from controlled entry is increased profit or
 when applied in conjunction with catch or effort                    other net benefit". It would be expected that any viable
 regulation;" to distribute benefits. Limited entry, licens-         controlled access scheme considered for the groundfish
 in~. and ",lick ('('n ifi('ates grant property        lt1 the
                                                                     resource" of l he' :\orthwest Atlantic would be directed at
fishery and thus directly control effort. Taxation                   preventing any new entrants and/or controlling the
 restri~ts effort by forcing out those vessels which are too         current levels of effort, allowing time to bring stock size
 inefficient to pay the tax, i.e., their harvesting costs ap-        and effort into an equilibrium; over time, changes in
 proximate their revenues; thus, taxation is an indirect             fleet strengt h, stocks, and economic conditions should
control on effort. Stock certificates are unusual in that            improve the allocation of resources, and thus, economic
thev are direct allocations of potential income. All of the          efficiency. \Vorking against this argument, however, is
sch~mes are attempts to resolve the problems associated              the fact that the current fleet appears capable of over-
with common property resources, e.g., dissipation of                 fishing; as a result, possible gains by controlled access
rent, inefficient allocation of goods and services, etc.             schemes mav be difficult to realize. It also should be
Their difference,; are based on the way they operate and             realized that the alleged misallocation of resources may
whether or not they directly control productive input or             not be the "beast" management needs to attack, since
output.                                                              little is known about the size of economic magnitude of
    During the past decade, various controlled access                the inefficiencies in the groundfish fishery, and whether
schemes have been widely discussed. There has not                    particular remedies are socially desirable. :\evertheless,
been, however, a consensus on their applicability. This              controlled access schemes probably offer some potential
has been particularly true for the ~orthwest Atlantic                for improving efficiency in terms of resource allocation,
fisheries. However, before devoting further attention to             prevention of overfishing, and improvements in the
the various forms of limited entry, we will discuss the              general welfare of society.
reasons why controlled access has been so often ad-
vocated.                                                                A primary problem of most controlled access schemes
                                                                     is deciding which vessels and/or harvesters will be in-
   It is well documented in the literature on fishery
                                                                     cluded or excluded. This is particularly true for licensing
economics that the unregulated. open-access fishery
                                                                     and stock-certificate programs. With stock certificates
result,; in an inefficient allocation of resources. :\1ore, or
                                                                     moreover. appropriate allocations must be determined
less. goods are produced than ,;ociety requires, or alter-
                                                                     and the problems potentially arising from transfer of cer·
nati\'~ly. production is not at minimum cost. The ques-
                                                                     tificates must be addressed. It may take several years
tion arises. whether the resources used in harvesting
                                                                     before the benefits of controlled access schemes are
could be hetter employed in another industry or sector of
                                                                     realized unless vessels are forced out of the fishery. In ad-
the economv with either a corresponding increase in the
                                                                     dition, at its present strength, the fleet may be capable
aggregate p~oduction of goods and services, or a decrease
                                                                     of overfishing in periods of low stock size.
in the existing overall costs of production.
    In the case of fisheries. inefficiency of production and            Taxation, another potential management tool,
allocation are considered to follow from their common                presents certain problems: it requires legislation: it in-
property nature. i.e .. resources are commonly owned but             creases the need for flexibility in management because
individually exploited. This situation creates a potential           taxes have to be adjusted in response to market changes;
for increasin!/: the harvest leither by expanding fleet-size         finallv, taxation requires an organization to appropriate
or effort) until the market price is equal to average cost;          and distribute tax revenues. However. taxation could
at this :evel. pure profit. rent. or producers' surplus (the         result in a level of effort consonant with maximum net
difference between revenue and costS) becomes zero                   benefits.
("dissipation of rent "). The common property nature of                 Controlled access schemes. though they are not
the resource coupled with economic conditions can                    without problems. offer a viable approach to managing
create an environment in which there exists a potential              fisheries for maximum net benefits. Other types of effort
profit for anyone wishing to seek it. Prospective entrants           regulations. which do not require limitations on entry,

are not. in general. directed at obtaining maximum net              economic sector of the system. Incentive-disincentive
benefits for society; they are primarily directed at                plans and price controls can be used to control fishing
reducing fishing mortality rather than producing the                mortality indirectly. :Seither method has been applied
best allocation of goods and services.                              widely. but further analysis ma~' indicate then
                                                                    usefulness for this purpose.
                                                                       The allocation of benefits of exploitation is usually a
                      SUMMARY                                       secondary state of fisheries management. one which
                                                                    follows attempts to control fishing mortality. Trip limits.
   The optimal fisheries management technique depends
                                                                    vessel allocations. and controlled access are typically
on objectives of management, the legal authority of
                                                                    used for allocation although in some cases they may be
managers. and the information base supporting manage-
                                                                    used as passive methods for controlling fishing mortali-
ment. Fisheries management techniques should be
evaluated with respect to their (1) effectiveness in con-
                                                                       The primary method of controlling fishing mortality in
trolling fishing mortalit~·; (2) relationship to other
                                                                    the northeast has been catch restrictions. Trip limits
biological impacts: (3) relationship to the natural func-
                                                                    have been used to spread catch over time; this affects the
tioning of the fisheries system: (4) relationship to
                                                                    distribution of benefits. Effort regulation should be con-
harvesting efficiency: (5) historical precedent and public
                                                                    sidered as an alternative method of active control of
acceptance; (6) cost of enforcement and administration;
                                                                    fishing mortality for the Northeast region. Effort
(7 J impact on fisheries for nontarget components of the
                                                                    regulations are more robust scientifically and require
resource; (8) impact on the distribution of benefits; and
                                                                    less frequent amendment than catch regulations. Trip
(9) scientific robustness (or how likely is it that the
                                                                    limits promote inefficient harvesting and decrease com-
technique is appropriate given uncertainty in its scien-
                                                                    petition among harvesters. Other methods of allocation
tific bases?).
                                                                    should be considered in the future.
   Restrictions on catch and fishing effort are active
methods of controlling fishing mortality by regulating
harvesters. Catch restrictions are less robust scientifical-
ly than effort restrictions. Spatial-temporal restrictions,           The authors benefited from the generosity of J.
gear restrictions, and restrictions on the nature of the            McHugh, J. Douglas, D. Pierce, J. Lanzillo, and J.
catch are passive with respect to fishing mortality,                Zu boy. These individuals met with the authors to
although they may be effective methods of protecting                develop an outline of the content of this paper. They
some components of the resource. Fishing mortality is               offered many useful suggestions. 'Numerous discussions
theoretically unbounded when passive methods of                     with B. Brown and R. Hennemuth greatly influenced the
fisheries management only are applied.                              ideas presented here. 1. Strand. J. Graham, L. Smith
   Fishing mortality may be controlled indirectly by                and D. Pierce provided constructive criticism of an
management techniques which influence the socio-                    earlier version of this paper.