575
13 Conclusion
for answering some of the more challenging questions about aggregation dynamics,
but fundamental questions persist. For example, the meaningful counting of fi sh in
aggregations of thousands to tens of thousands, when fi sh mass in the water column
in three-dimensional ‘balls’, when numbers change daily, and when fi sh are moving
around calls for innovative approaches and careful planning. Maybe techniques
applied to the quantifi cation of fl ocks of birds and the use of video and other technology could help to improve accuracy. New 3D image technology holds promise for
better quantifi cation of numbers and sizes of fi sh in aggregations. It has become very
clear that the monitoring of fi sh numbers in aggregations under anything more than
the most benign situations, with low numbers of fi sh in a small shallow area, requires
a high degree of expertise and should not be conducted without careful planning.
Studies of the physical characteristics of aggregation and spawning sites, as well
as the biology of species, are needed to place the aggregation within physical and
ecological contexts. Bathymetric surveys and other mapping of aggregation sites,
along with the use of “control sites” without aggregations, are important for
determining what characterizes used sites. Similarly, physical measurements
(temperature, currents, etc.) need to be continued outside of the times and locations of
aggregation and spawning, and ideally year-round, to be able to detect conditions
that might be specifi cally associated with locations and seasons of spawning.
In most places we learn of aggregations through local ecological knowledge
(LEK), usually from fi shing communities, while LEK is an important driver of
protective actions in some parts of the world, especially in some Pacifi c Island
countries. In Chap. 10 Rick Hamilton, Yvonne Sadovy de Mitcheson and Alfonso
Aguilar-Perera examine the role of LEK in documenting and managing aggregations. Many that are revealed through LEK have persisted for decades at subsistence
fi shing levels, only to become reduced after the addition of commercial pressure.
Carefully collected LEK provides highly useful information on historical and current
status of aggregation fi sheries and provides valuable perspectives on attitudes and
understanding of local marine resources. However, it is important to collect such
information carefully and systematically and to validate it independently, whenever
possible, before integration into management planning.
Although LEK can be very detailed, it is the combination of LEK and science that is
most likely to lead to effective fi sh spawning aggregation management. The interview
process for LEK can provide excellent opportunities for awareness and information
exchange between fi shers and researchers, but interviewers need to be knowledgeable
and well-trained. Scientists can play a valuable role by sharing their knowledge and
answering questions fi shers may have. Scientists can also provide regional and global
perspectives on fi sh spawning aggregations (FSAs), something even the most knowledgeable fi shers typically lack; many local fi shery departments and educational
bodies likewise have little knowledge of this aspect of the marine ecosystem and local
fi sheries. Often, informing fi shers of the critical biological role that FSAs play and the
ease with which they have been destroyed in other places is the catalyst for communities to initiate the process of managing their own aggregations.
The challenge of management is tackled by Martin Russell, Brian Luckhurst and
Ken Lindeman in Chap. 11 . Management is particularly diffi cult since most aggregations,
13 Conclusion
for answering some of the more challenging questions about aggregation dynamics,
but fundamental questions persist. For example, the meaningful counting of fi sh in
aggregations of thousands to tens of thousands, when fi sh mass in the water column
in three-dimensional ‘balls’, when numbers change daily, and when fi sh are moving
around calls for innovative approaches and careful planning. Maybe techniques
applied to the quantifi cation of fl ocks of birds and the use of video and other technology could help to improve accuracy. New 3D image technology holds promise for
better quantifi cation of numbers and sizes of fi sh in aggregations. It has become very
clear that the monitoring of fi sh numbers in aggregations under anything more than
the most benign situations, with low numbers of fi sh in a small shallow area, requires
a high degree of expertise and should not be conducted without careful planning.
Studies of the physical characteristics of aggregation and spawning sites, as well
as the biology of species, are needed to place the aggregation within physical and
ecological contexts. Bathymetric surveys and other mapping of aggregation sites,
along with the use of “control sites” without aggregations, are important for
determining what characterizes used sites. Similarly, physical measurements
(temperature, currents, etc.) need to be continued outside of the times and locations of
aggregation and spawning, and ideally year-round, to be able to detect conditions
that might be specifi cally associated with locations and seasons of spawning.
In most places we learn of aggregations through local ecological knowledge
(LEK), usually from fi shing communities, while LEK is an important driver of
protective actions in some parts of the world, especially in some Pacifi c Island
countries. In Chap. 10 Rick Hamilton, Yvonne Sadovy de Mitcheson and Alfonso
Aguilar-Perera examine the role of LEK in documenting and managing aggregations. Many that are revealed through LEK have persisted for decades at subsistence
fi shing levels, only to become reduced after the addition of commercial pressure.
Carefully collected LEK provides highly useful information on historical and current
status of aggregation fi sheries and provides valuable perspectives on attitudes and
understanding of local marine resources. However, it is important to collect such
information carefully and systematically and to validate it independently, whenever
possible, before integration into management planning.
Although LEK can be very detailed, it is the combination of LEK and science that is
most likely to lead to effective fi sh spawning aggregation management. The interview
process for LEK can provide excellent opportunities for awareness and information
exchange between fi shers and researchers, but interviewers need to be knowledgeable
and well-trained. Scientists can play a valuable role by sharing their knowledge and
answering questions fi shers may have. Scientists can also provide regional and global
perspectives on fi sh spawning aggregations (FSAs), something even the most knowledgeable fi shers typically lack; many local fi shery departments and educational
bodies likewise have little knowledge of this aspect of the marine ecosystem and local
fi sheries. Often, informing fi shers of the critical biological role that FSAs play and the
ease with which they have been destroyed in other places is the catalyst for communities to initiate the process of managing their own aggregations.
The challenge of management is tackled by Martin Russell, Brian Luckhurst and
Ken Lindeman in Chap. 11 . Management is particularly diffi cult since most aggregations,