276
Y. Sadovy de Mitcheson and B. Erisman
spawning species aggregate at outer shelf edge areas, including drop-offs and reef
passages. These are habitats that could be incorporated into marine protected areas
since they currently receive little management or protection.
While in principle it should be possible to control fi shing activity on aggregations to within sustainable levels, in practice this is unlikely to occur. Moreover, we
still understand little of the implications of overfi shing or of selective fi shing on the
long-term persistence of populations of aggregating species. And, even when management is in place, compliance is often low and enforcement typically falls short
of being suffi cient. For these reasons, it is clear that the most practical and precautionary approach is to avoid anything other than subsistence aggregation-fi shing, at
least in the case of transient aggregations, and to treat them as critical sources of fi sh
that require protection for the benefi t of the fi shery. This situation calls for extreme
caution in widely revealing the locations of little-known aggregations since it could
easily expose them to greater fi shing pressure. It also calls for consideration of the
future of fi sheries that depend exclusively on spawning fi sh, such as for roe or
because the reproductive season is the only time that ripe fi sh can be caught.
More effort is needed to directly survey and monitor aggregations, since fi sherydependent data may not always refl ect the status of aggregations (due to hyperstability), and to assess the economic value under scenarios ranging from unmanaged
to fully protected aggregations. While new technologies may be applied or developed
to survey aggregations at locations in which diver surveys are not possible, care is
needed to assess their reliability, as in the case of hydroacoustic methods. Economic
analyses are needed of aggregating fi sheries, alternative use activities, and of assessments of the importance of aggregations to ecosystem structure and health. Finally,
the benefi ts of managing and protecting aggregations need to be communicated to
stakeholder groups, policy makers, and the general public so that consensus, support
and compliance for policies are obtained.
Underpinning progress in management is a need for a shift in understanding
about the importance of aggregations for both the fi shery and the fi sh themselves. In
particular, the ‘illusion of plenty’ that a healthy aggregation will inevitably produce
represents a particular challenge for aggregation-fi sheries. In many situations, it
will be necessary to undergo a major paradigm shift, from seeing spawning aggregations as special opportunities for fi shing to understanding them as particularly
important times at which fi sh need to be protected, to ensure that they produce the
next generation.
References
Aalbers SA, Drawbridge MA (2008) White seabass spawning behavior and sound production.
Trans Am Fish Soc 137:542–550
Aburto-Oropeza O, Erisman B, Valdez-Ornelas V et al (2008) Commercially important serranid
fi shes from the Gulf of California: ecology, fi sheries, and conservation. Cienc Marina Conserv
1:1–44
Y. Sadovy de Mitcheson and B. Erisman
spawning species aggregate at outer shelf edge areas, including drop-offs and reef
passages. These are habitats that could be incorporated into marine protected areas
since they currently receive little management or protection.
While in principle it should be possible to control fi shing activity on aggregations to within sustainable levels, in practice this is unlikely to occur. Moreover, we
still understand little of the implications of overfi shing or of selective fi shing on the
long-term persistence of populations of aggregating species. And, even when management is in place, compliance is often low and enforcement typically falls short
of being suffi cient. For these reasons, it is clear that the most practical and precautionary approach is to avoid anything other than subsistence aggregation-fi shing, at
least in the case of transient aggregations, and to treat them as critical sources of fi sh
that require protection for the benefi t of the fi shery. This situation calls for extreme
caution in widely revealing the locations of little-known aggregations since it could
easily expose them to greater fi shing pressure. It also calls for consideration of the
future of fi sheries that depend exclusively on spawning fi sh, such as for roe or
because the reproductive season is the only time that ripe fi sh can be caught.
More effort is needed to directly survey and monitor aggregations, since fi sherydependent data may not always refl ect the status of aggregations (due to hyperstability), and to assess the economic value under scenarios ranging from unmanaged
to fully protected aggregations. While new technologies may be applied or developed
to survey aggregations at locations in which diver surveys are not possible, care is
needed to assess their reliability, as in the case of hydroacoustic methods. Economic
analyses are needed of aggregating fi sheries, alternative use activities, and of assessments of the importance of aggregations to ecosystem structure and health. Finally,
the benefi ts of managing and protecting aggregations need to be communicated to
stakeholder groups, policy makers, and the general public so that consensus, support
and compliance for policies are obtained.
Underpinning progress in management is a need for a shift in understanding
about the importance of aggregations for both the fi shery and the fi sh themselves. In
particular, the ‘illusion of plenty’ that a healthy aggregation will inevitably produce
represents a particular challenge for aggregation-fi sheries. In many situations, it
will be necessary to undergo a major paradigm shift, from seeing spawning aggregations as special opportunities for fi shing to understanding them as particularly
important times at which fi sh need to be protected, to ensure that they produce the
next generation.
References
Aalbers SA, Drawbridge MA (2008) White seabass spawning behavior and sound production.
Trans Am Fish Soc 137:542–550
Aburto-Oropeza O, Erisman B, Valdez-Ornelas V et al (2008) Commercially important serranid
fi shes from the Gulf of California: ecology, fi sheries, and conservation. Cienc Marina Conserv
1:1–44