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- Kees
Zwanenburg
- Department of
Fisheries and Oceans
- Halifax, Nova
Scotia
The Incorporation of Local
Fisheries Knowledge into the Fish Stock Assessment
Process
Introduction
It has been the contention of
fishermen and others that there is a large store of local
knowledge which should be incorporated into the assessment
of fish resources. It has been said that if such information
had been incorporated into the assessment process over the
history of this process, the resources may not have declined
to the extent that many of them have. Before one can debate
whether or not this is so or begin to determine how such
information might be used, there are a number of fundamental
questions that need to be answered. The most obvious of
these are what is meant by local knowledge, what is meant by
fish resource assessment, and what are the objectives of
combining the two.
One view of the objectives of fish
resource assessments and the management of those resources
based upon advice stemming from such assessment, is to
ensure the long-term sustainability of Canada's fisheries.
Although it has not been clearly defined exactly what this
means it surely implies that these resources should only be
exploited to the extent that there is good expectation of
future generations being able to exploit them at roughly
similar rates. Although this is very inexact it does give
the idea that we should be resource stewards rather than
extracting profit from them at any cost to their future.
This however is only one possible vision. Another equally
possible objective of fisheries management could be, to
extract the maximum amount of profit from the resource
within the most appropriate time-frame and without regard
for future resource viability. Fishermen probably hold the
entire range of opinions about possible objectives for
fisheries management, from long-sustainability of our
fisheries to the maximization of short-term profit only.
Fisheries scientists and managers on the other hand are
responsible for ensuring the long-term sustainability of the
fishery. This will put them in conflict with some fishermen
and will put them in agreement with others, a fact relevant
to the incorporation of local knowledge in that it provides
motive or incentive to fishermen to report their knowledge
in a manner consistent with their objectives. It their
objectives include an aspect of long-term sustainability, or
a notion of wanting to pass on the resource to their future
generations, reporting of knowledge is likely to be more or
less consistent with the objectives of fisheries scientists,
meaning that knowledge will be passed on without
interpretation. If their objectives are to maximize
short-term profit without reference to the future, there is
incentive to interpret observations and report knowledge in
a manner that minimizes the restrictions put on that profit.
An example would be the under-reporting of catch. Under a
TAC base management system non-reporting of catches
precludes the closure of the fishery by ensuring that the
TAC is never actually reached, at least on paper. It also
leads to over-exploitation of the fisheries which may have
an impact on long-term viability. Even in the case where a
fisherman "believes" in the objective of long-term
sustainability, economic realities can potentially influence
the objectivity with which local knowledge would be
provided. It is against this background that local knowledge
needs to be interpreted. It implies that there is a need for
assuring ourselves that the data are reliable in that they
represent the "truth" as nearly as is possible.
Conflicts over resource
exploitation between fisheries scientists and fishermen have
arisen many times in the past. One reason for this is the
desire, on the part of some fishermen, to fish without limit
and without regard for the future of the resource. Another,
and equally serious reason for conflict is the lack of
agreement between fisheries scientists/managers, and
fishermen on the condition or abundance of the stocks being
exploited. In some instances fisheries scientists conclude
on the basis of their analyses that a particular stock is
being or has been depleted, while the fishermen exploiting
that resource maintain that this is not so, based on their
observations from the fishery. Sometimes fishermen maintain
such a position in the absence of any real belief that it is
true, because of purely economic considerations. Maintaining
such a position has, in the past, resulted in increased
profits through increases in TAC levels. At other times
these conflicts arise because there is genuine puzzlement,
the fishermen genuinely believe their observations to
indicate the opposite of what the "scientists" say. In these
situations it is likely that the co-operative exploration of
how and what segments of local knowledge could be
incorporated into the resource assessment process, could
resolve such conflicts and result in both parties gaining
new and useful insights into how these resources should be
exploited and managed.
It needs to be made clear at the
outset that there should be room in this process to change
radically our approach to resource assessments as well as
the way in which fishermen operate. Although most of what
follows will be written in the context of the process as it
is presently defined, there needs to be an understanding
that it is not necessarily the only way to do the job.
Neither is it sensible to throw the baby out with the bath
water. There are clearly elements of the present resource
assessment process which are "right" and should be
preserved. An example of this is the issue of using only the
most reliable information on which to base decisions. It is
not sensible or desirable to develop a process based on
unreliable information, opinion, folklore or hearsay.
Although the insistence on reliable and verifiable
information will present us with many problems in our
attempts to incorporate local knowledge, without it we would
be building a house of cards.
Resource
Assessment
It is useful to begin by defining
what is meant by resource assessment, since this will
dictate, to some extent, the kind of local knowledge that
may be relevant to the process. Fish resource assessment, in
its simplest present definition is the process of
estimating, with the highest degree of reliability, two
aspects of any self-reproducing population of fish. The
first is determining how many of them there are in the
population now, and the second is determining how many there
will be next fishing season. Although this is somewhat
simplified, it is in essence what the process tries to
accomplish.
At present, determining how many
fish there are is done through surveys. The most prevalent
gear type used to conduct surveys are otter trawlers because
they are relatively non-selective and can survey large
geographic areas in a relatively short time. The
non-selective nature of the gear type (research trawls use _
inch liners in the cod end) is advantageous in that a single
survey can be used to determine the abundance of a number of
species and size classes at once. Estimating the number of
fish that will be in the population the following year is a
more multifaceted process which uses information from
surveys, estimates of removals from catch statistics, and a
wide variety of biological information on population age
structure, growth rates, maturation schedules, and the
relationship between present population numbers and future
recruitment.
Local Fisheries
Knowledge
Local fisheries knowledge, in its
broadest sense, is the wealth of experience that has been
accumulated over time by fishermen fishing in any given
area. It includes every aspect of fishing from local weather
conditions, to vessel operation, to the rigging of fishing
gear, to sale of the catch, and everything in between. It is
the knowledge which defines the "fishing way of life" for
that particular area and sets it apart from other ways of
making a living. Not each fisherman in any given area
necessarily has all of the local knowledge at his or her
disposal, he or she may not even have access to it all. For
example, fishermen tend to be secretive about certain
aspects of the local knowledge base which they feel gives
them a competitive advantage over other fishermen or over
any restrictive management system. This may include such
things as exact times and places to fish, the specific
rigging of gear to capture particular species, or the total
amount of fish of any or all species caught. So although the
local fisheries knowledge is that accumulated by all
fishermen, not all fishermen have all the information. It
also means that documenting the sum total knowledge would
require talking to all of the fishermen in the area rather
than a selected few. One might question whether or not the
sum total of all local knowledge is required as input to the
assessment process.
Local knowledge can be classified
into two broad categories, qualitative knowledge,
meaning that it is not gathered by measuring things, and
quantitative knowledge, which means that it is
gathered by measuring things. An example of qualitative
knowledge would be a person's memory of how cold a
particular winter was relative to another, while
quantitative information would be the actual temperature
records for each of the winters in question. In addition to
these two broad categories, information can be recorded in a
variety of ways. Much of what makes up local knowledge is
recorded in the memories of people, while, in general, only
a small fraction is actually recorded in written or other
form. Unfortunately for anyone who wishes to use local
knowledge in any highly formalized process such as fish
stock assessment, memories are rarely perfect and tend to
become less reliable as time passes. Even if the information
stored in memory is only a few days or weeks old, it is
usually less reliable than that which has been recorded (on
paper or some other medium) within minutes or hours of the
event. Just try to remember what you had for lunch last
Tuesday.
The fact that most local knowledge
resides in memory makes it imperative that we develop
reliable ways of gathering that information and ways to
ensuring that it represents the "truth" as closely as is
reasonably possible. Social scientists have been gathering
and working with these kinds of data for quite a long-term
and it is likely that we can learn a lot from them in
setting up data collection protocols to collect particular
portions of the local knowledge which resides mainly in
memories. It is not appropriate to discuss these methods in
the present discussion, however one general result that they
have discovered is that since the only way to collect this
information is through questionnaires or interviews, the
questions asked have to be very carefully prepared to make
sure that they are as unbiased as possible. Biased questions
lead to the collection of biased information. An simplistic
example of a biased question from which to determine a
fisherman's primary source of income might be something like
"Did you make more money this year from cod or haddock?",
without providing the respondent an opportunity to state
that most of his income actually came from lobster. Using
the results of this question to given some indication of
which species contributed most to income would give a very
misleading picture.
Local knowledge can be further
classified as historical and current. Although the boundary
between these types of information is somewhat arbitrary it
may be best to think of the historical knowledge as that
portion of local knowledge against which current information
is judged. An example of historical knowledge might be that
winters are colder than summer. This means that a -15ūC day
in January would come as no surprise, whereas a 30ūC day
during that same month would be a great surprise. Historical
knowledge can take many forms ranging from a general
knowledge of fish distribution to effects of weather on
catch rates for particular species, to the exact manner or
rigging particular gear to catch particular
species.
Historical local knowledge is also
that portion of the knowledge base that allows fishermen to
make predictions on the basis of present conditions. An
example of this might be the association of certain wind
directions and/or velocities with particular expectations of
catch rates, either high or low. Short term predictions like
these are used to make decisions about the days activities
namely whether or not to go fishing, or how much effort to
expend. Historical knowledge is also used to make
longer-term predictions. An example of this was quoted in a
recent publication by Finlayson (1994) where it was
indicated that the Newfoundland inshore trap fishermen were
quoted as having predicted the decline in the northern cod
stock by observing significant declines in their cod-trap
catch rates and the size composition of the cod-trap catches
during the mid-1980s. The inshore fishermen's contention
appeared to be that the offshore fleet was exerting such
heavy fishing pressure that there were no fish left to come
ashore and be caught in their traps. The reduction in size
composition was apparently also seen as an indicator of
overexploitation. These observations in tandem, it was
claimed, led to the prediction that there had been, and
would continue to be a drastic decline in the overall
abundance of the Northern cod stock.
In neither the Northern cod
situation, where fishermen were making long-term predictions
about an overall decline in a resource, or in the situation
where a decision to fish or not to fish on a particular day
is based on weather observation is the underlying mechanism
necessarily understood. The predictions could be based on
the observed long-term association or correlation of
particular observations or events to which cause and effect
are ascribed. Although predictions based on such correlated
observations may be reliable most of the time there are no
guarantees. Just how reliable such predictions are depends
(at least in part) on how often the predictions have been
put to the test. The prediction of relative catch rates
based on weather conditions are likely to have been tested
enough times that individuals feel relatively confident in
using it to make what amount to business decisions which
will have a direct impact on their incomes. In the case of
the predictions about changes in the overall abundance of
the Northern cod it is difficult to judge whether or not the
associations used would be reliable on average or not. In
this case, the resource indeed declined but it is uncertain
how many times in the past such claims have been made
without the observed decline. The fundamental difference
between the two examples is that in the case of the
association of wind and catch rates, the "theory" can be
tested frequently, whereas for Northern cod, or for any
other fish stock, predictions can be tested with only a
fraction of the frequency. Such a limited set of
observations make if difficult to judge the generality of
the predictions being made, it makes it difficult for people
to accept the predictions.
In the present model of resource
assessments historical knowledge can only be incorporated if
it is quantitative and if it has been formally recorded and
is more or less verifiable. This means that the vast
majority of historical local knowledge is not available to
the process. Most fishermen have not recorded all of the
details of their fishing operations in a logbooks. The
challenge therefore is to find a way to make the informal
historical local knowledge acceptable to the process or
fundamentally to change the process so that the need for
formal recorded and verifiable information is removed.
Although the resource assessment process is likely to change
in many ways in the near future, it is unlikely that it will
function without some kind of formally structured,
verifiable input data, it is therefore probably more
fruitful to look for ways of formalizing the local
historical knowledge than to reply on the changes the
process to obviate the necessity of such data.
There have been calls for
fundamental changes to the assessment process, one of which
is more and effective incorporation of local knowledge into
the process. The belief is that by using this additional
source of information, it will be possible to make better
predictions about future fish abundance. On the other hand
there are those who maintain that the whole idea of
predicting next year's fish abundance based on this year's
information, with any reasonable degree of accuracy, is
impossible. If this were the case then no amount of
information, local or otherwise, will allow us to make
predictions were would be assuming that the ecosystem which
is being harvested is a chaotic system with regard to fish
production. The word chaotic here essentially means
unpredictable. Most knowledgeable individuals however,
content that, although the system is variable, and although
there are likely some chaotic components, there is enough
predictability in the system to make it worthwhile trying.
The challenge then, is to determine to what degree the
system is predictable and what can be used to make those
predictions. At present the suite of variables used is
relatively limited, and it is possible that by incorporating
local knowledge we use a broader base of variables on which
to make predictions. This may mean that our concept of what
is acceptable as reliable input data could be significantly
modified. It may also mean that the models that we presently
use the data in, may change from what they are now. It is,
however, unlikely that these changes will include giving up
the concept of reliable verifiable data upon which to base
our predictions.
What of
Incorporate
Before discussing the particular
elements of local knowledge which may be amenable for
incorporation into the assessment process, there is a
potential role for local knowledge in the more general role
of defining areas of research of relevance to the stock
assessment process. There is a precedence for this in the
field of pharmaceutical development. In this case, local
lore regarding the medicinal properties of plants is
recorded and used to identify plants of potential interest
to pharmaceutical manufacturers. In the case of fisheries
such local knowledge could be used to identify processes
relevant to the assessment of fish resources. In particular,
local knowledge about indicators of resource abundance or of
recruitment should be recorded, evaluated for feasibility in
developing independent indices of population
attributes.
I. Fish Distribution and Surveys
of Abundance of Target Species
The simple definition of the
assessment process given above helps in defining what
portion of the local knowledge might be explored for
incorporation. Historical knowledge of fish distribution may
be extremely valuable for use in the present assessment
process, particularly in modifying present surveys designed
to determine abundance. Under the present stock assessment
model, each stock is defined as a more or less independently
reproducing population of fish which is separate from other
such stocks. Most of the stocks, as presently defined,
occupy very large geographic areas, for example 4VsW or
Eastern Scotian Shelf cod occupy all of NAFO divisions 4V
and 4W, an area of many thousands of square miles of ocean.
It is assumed that all of the cod occurring in this area
belong to a single reproducing population. In order to
estimate the abundance of this population, therefore, the
entire area must be surveyed over a relatively short time.
If it took too long, say months, the number of fish could
change significantly due to fish dying or being added to the
population by recruitment between the beginning and end of
the survey. The approach that has been taken for these
surveys is to subdivide the entire stock area into smaller
areas which share some common features such as depth.
Subdivision of a large stock area (called stratification) is
done to make the problem of estimating overall abundance
from a survey of what amounts to only a small portion of
their area more tractable. By stratifying we make the
assumption that within each of the subdivisions (or strata)
the relative abundance of fish is different from the
relative abundance in other strata. For example, Emerald
Basin is defined as a single stratum as is Emerald Bank. We
know from experience that the abundance of cod and haddock
in Emerald Basin is lower on average than it is on Emerald
Bank. We have also learned that no matter where you fish
within Emerald Basin, the abundance is relatively low, and
conversely that no matter where you fish in Emerald Bank,
the abundance of cod and haddock is relatively high. Notice
that here the word relatively means that the catch
rates are being compared only between Emerald Basin
and Emerald Bank, and not to catch rates on the eastern
Scotian Shelf in general. This does not mean that there are
not a few places in Emerald Basin where on occasion you
would not catch more cod or haddock than on Emerald Bank,
but that on average this is not the case. We assume from
these observations that within the strata the distribution
of cod and haddock is relatively uniform. This means that
the all portion of a stratum are similar as far as the
distribution of cod and haddock goes. Therefore, to make the
job of estimating overall abundance of, say 4VsW cod,
somewhat tractable we assign a certain number of survey sets
(tows) to each of the strata rather than randomly to the
stock area as a whole. From the results of these tows we
estimate the abundance of each stratum simply by multiplying
the total number caught in the portion of the stratum
surveyed by the total area of the stratum. This is done by
calculating how much bottom area the trawl sweeps in a
standard tow and then determining how many tows it would
take to cover the whole area. Once this is determined we can
multiply the observed average catch per tow from all tows
done in the area by the number of tows it would take to
cover the whole stratum to determine the total number or
weight of fish present in the stratum. Adding the abundance
estimates for each stratum gives us an estimate of abundance
in the whole stock area.
One of the assumptions in this is
that all portions of a stratum are alike. Some of these
strata are very large (Figure 1). Fishermen fish in very
specific locations which are usually much smaller than the
survey strata as presently defined. If there are certain
areas within stratas where fishermen fish in preference to
other areas, they must be assuming (based on experience,
local knowledge) that there are differences in the relative
abundance from one portion of the stratum to the other. If
this is so, it may be that this information needs to be
incorporated into present survey design. The reason for this
can be illustrated by a simple example. If in a particular
stratum in a particular year all of the sets were allocated
to areas where the local fishermen felt there were no fish,
then the estimated abundance for that stratum would be very
low or zero. This would then not be consistent with what the
fishermen observed during that year and would result in an
underestimate of the true abundance for that stratum. This,
in turn, would lower the estimate of overall abundance in
that year. To overcome this potential problem, the local
knowledge of fish distribution at the time during which
surveys are conducted, could be used to re-define the
stratum boundaries such that within strata the distribution
of fish is more likely to be uniform. Using this information
to modify our survey stratification scheme could make it so
that our assumption of uniform distribution of fish within
strata would be more likely to be true. Using such an
improved stratification scheme could result in more reliable
estimates of abundance.
Having identified an element of
historical local knowledge which could be incorporated into
an aspect of the assessment process it remains to determine
whether or not the form of this information is such that it
actually can be incorporated into the present assessment
process. To determine this we need to know where this
information is, how extensive it is in terms of geographic
area covered, if we can get access to it, and if it is
reliable enough to make changes to the present survey
stratification scheme.
Fishermen have historical knowledge
about the distribution of fish within the present strata
based on some number of years of experience fishing in a
particular area. Some have longer histories than others in
the fisheries and have, therefore, been observing these
distribution patterns for longer. For example, a fisherman
who has been fishing particular grounds for 20 or 30 years
will have a better appreciation of the level of variability
in distribution patterns that a particular species can
demonstrate than a fishermen who has only fished there for 2
or three years. In order for such information to be most
useful we should be incorporating the longest available
(reliable) historical data series we can. This will allow us
to judge whether or not a particular shift in distribution
in any given year is out of the ordinary or within the range
of previous observations.
Since memories are inherently
unreliable and since they fade over time, particularly where
details are concerned, the ideal form of this kind of
information would be from actual personal logbooks.
Therefore, before considering whether or not we could
incorporate local historical knowledge of fish distribution
to modify the present survey stratification scheme, we need
to determine how much of this information is in the detailed
form of logbooks and how detailed and reliable the
collective memories of fishermen are about fish
distribution, where logbooks are not available. Such
information also needs to be closely linked to information
on the relative efficiency and types of gears used since
these have a large impact on perceptions of relative
abundance. Fishing in any one location with different gear
types could give very different impressions of the relative
amounts of fish at any particular location.
The ideal form of this information
would be as carefully kept personal fishing logs which
recorded the data, time, latitude, longitude, depth and
effort of very fishing set conducted by the fishermen.
Although a portion of the information probably exists in
this form and could be used directly, the majority if
probably either in logbooks with a highly variable degree of
detail, or exists only in the memories of the fishermen. It
is likely that this information could be collected both by
analyzing personal logbooks and, where these are not
available, through a carefully designed
interview/questionnaire process.
II. Distribution on Non-Target
Species
In addition to historical
distributional information on target species, that is
species that are actively fished for such as cod, haddock,
pollock, halibut, hake, redfish and some others, the above
information may be available for by-catch species, species
caught incidentally and probably mainly discarded. All of
the same restrictions as have been outlined in I above apply
to these data with the additional problem that the amount of
recorded information is likely to be even smaller than is
the case for the target species. It is, however, worth
pursuing this information since these incidental catches may
be useful as indicators of what the ecosystem as a whole was
doing.
It is clear to both fishermen and
fisheries scientists that the target species do not live in
isolation. They are part of a more or less complicated web
of interrelations both as prey and predator. These
interrelations have not been taken into account in the
assessment process in any significant way until very
recently and then in only a very limited way. This lack of
incorporation has in part been due to the general lack of
detailed information non-target species in general and of
non-target species in the fisheries in particular. It may be
that examining the changes of other species in the ecosystem
being fished will give us more clues as to how the system as
a whole works. For example, what is the relationship between
sculpin on Sable Island Bank and the subsequent appearance
of halibut on the Bank. Are the sculpin a prey species on
which halibut rely? What is the effect of removing 1200MT of
shrimp on the Scotian Shelf ecosystems' ability to produce
cod recruits? What is the effect of removing 40,000MT of
silver hake on the survival of pollock juveniles? What is
the effect of removing 100,000MT of herring on the
ecosystems' ability to support cod growth and reproduction?
Although the information on by-catch species composition
will not necessarily lead to answers to these questions in
the short-term they may, because of the long-term and
relatively broad scale nature, provide new clues which will
point to answers or new work leading to better predictions
of future abundance. For example, there are those who
maintain that the recent decline in eastern Scotian Shelf
cod is, in part, due to the level of exploitation of herring
stocks in the area. They maintain that the herring provide a
significant food source for the cod and that by fishing the
herring down, the cod are deprived of food and therefore do
not grow or reproduce as well. Is there historical local
knowledge about this possible linkage? Are there
observations which show a decline in cod catches (or size
composition) following poor herring years? Exploration of
this aspect of historical local knowledge in general may
also reveal indicator species, species whose presence or
change in distribution or abundance precede particular
changes in present target species or which herald changes in
general environmental conditions (for example, the increase
in the abundance of capelin on the eastern Scotian Shelf
over the past number of years as an indicator of declining
water temperatures).
These data could also reveal
historical exploitation patterns for species which were
treated as by-catch in the past, but now form the basis of
commercial fisheries. An example of such a fishery would be
the newly evolving skate fishery. In the past, skate were
considered a nuisance in the cod and haddock directed
fisheries and were discarded from the catches. Now these
skate form the basis of a potentially valuable fishery. In
order to determine what levels of exploitation might be
appropriate for this new fishery we could examine historical
local knowledge for information on the frequency and rates
of skate by-catch. Knowing this would give some indication
of a potentially sustainable exploitation rate given that
skate appear to have survived in sufficient numbers to
warrant a fishery.
This information could also be used
to identify fish resources which have previously not been
exploited, but which exist in sufficient numbers to
potentially support a fishery.
III. Catch Composition and
Ecological Costs
Information like the true species
composition of catches (as opposed to landings) could also
be used to begin determining a portion of the relative
ecological costs of one fishery relative to another. Since
no fishery operates without some incidental or by-catch
problems exerts some pressure on the ecosystem in addition
to that resulting from the actual removal of target species.
Recent work by Alverson et al. (1994) which examined the
problem of by-catch and discards form a global perspective,
concluded that there were significant differences in the
levels of by-catch and discarding between gear types and
fisheries. By comparing the true catch compositions from
several gear types it might be possible to begin objectively
comparing their relative impacts. Once the relative impacts
of various fisheries are known these can be taken into
account in future management schemes. One example might be
to tax fisheries on the basis of the by-catch/discard costs,
where a fishery with low discards is given more access to a
resource than one with high discards. This is an extremely
important and urgent area of research. Alverson et al.
(1994) conclude that globally, some 27 million tons of fish
and shellfish are discarded each year. These are staggering
figures, especially when compared to the few hundred or
thousands of tons of fish which are landed in total in our
region. It is likely that ways of reducing these discards
will be one of the most important issues relative to future
fisheries.
IV. Estimates of
Removals
One of the most fundamental pieces
of information that is required in order to predict the
abundance of fish in the next time period is the total
amount (number) of fish removed during the present time
period. It is also one of the most difficult to obtain
reliably. Since our management schemes presently use total
allowable catches (TACs) to limit the removals from any
particular stock there is a significant incentive to
underreport actual catches. If catches are not reported, or
are reported as having been taken from another stock
(misreporting) it will result in a longer fishing season,
and a potentially greater revenue for the fishermen.
Unfortunately, since these "official statistics" of removals
are presently also the only source of information that
fisheries assessment scientists have available to estimate
the level of exploitation of any given resource, it can
result in incorrect estimates of exploitation rates. This
had significant implications for the predictions of fish
abundance in the following period. In general, it results in
an overestimation of present stock size and inflated
estimates of future abundance. It has been contended that
the problems of misreporting that in recent years, with the
implementation of ITQs, dockside monitoring programs, and
other regulations, that catch statistics have become more
reliable than they were in past years. It is, however,
difficult to evaluate this contention.
Obtaining reliable historical local
knowledge on levels of misreporting would allow for better
evaluation of present assessment models. In other words, if
the models were given the "right" information would they
have done better in predicting the observed declines, or
even better, would they have allowed us to formulate advice
which prevented the declines. Better present estimates of
catches through local knowledge would allow us to evaluate
the true performance of our assessment models in estimating
stock abundance and predicting future yield. All claims to
the contrary notwithstanding there is still serious concern
regarding the reliability of catch statistics on the part of
both fishermen and fisheries scientists.
The most effective source of both
the historical and present information on local knowledge of
removals in this case would be either, through individual
personal logbooks, if these were kept in sufficient detail,
or through sales records for individuals at local fish
plants if these were kept in sufficient detail.
Preliminary
Conclusions (based only on what is presented above,
point form for now)
- There must be a willingness on
the part of both fishermen and fisheries
scientists/managers to adopt new ways of solving old
problems.
- Some aspects of the present
process should be preserved.
- The objectives (motives) of the
providers of the knowledge could have an impact on how
the knowledge is presented.
- Local knowledge is composed of
both an historical and a current component.
- To each of these there are both
quantitative and qualitative aspects.
- Much of the historical data is
available only as memories which will require development
of effective surveys (interviews and
questionnaires).
- Knowledge of fish distribution
could potentially be used to refine present
stratification schemes for groundfish abundance
surveys.
- Knowledge on species
composition of catches could allow for the development of
ecological costs by which different could be compared or
taxed.
- Knowledge on the level of
misreporting could be helpful in evaluating the
performance of the stock assessment procedures in
retrospect.
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