569
13 Conclusion
spawners, aggregations are less likely to be present where fi shing pressure is high.
For example, in the Philippines and Indonesia, both intensively fi shed and with very
little fi shery management, few aggregations have been reported relative to the number
of fi sher interviews conducted (SCRFA country reports: www.SCRFA.org ). On the
other hand, in the western and central Pacifi c, where fi shing pressure is increasing
but is overall considerably more moderate, there are many reports of aggregations,
particularly in the lesser fi shed areas (Sadovy de Mitcheson et al. 2008 ) . We also
know that management can restore depleted aggregations. Such observations suggest
that (1) healthy aggregations are associated with healthy fi sheries, (2) it is important
and possible to proactively manage remaining aggregations and (3) aggregations
might prove to be useful indicators of fi shery condition.
As scientists we take the long view, a necessity when so many fi sh populations
and reefs in general are deteriorating (e.g. Wilkinson 2008 ) . Fish populations can
eventually recover from overfi shing provided the right management environment is
available and the species is not critically depleted. However, it is possible that biological or physiological factors may slow or even stall recovery at low population
sizes, as has evidently been the case for Atlantic cod (Rowe and Hutchings 2003 ) ,
signalling that we cannot wait until the last minute (i.e. numbers of animals have
been much reduced) before we act, and still assume recovery is inevitable. In
extreme cases, this may mean total closure of a fi shery. Such a drastic measure may
have recreational and commercial fi shers up in arms, and will almost certainly be
politically challenging, especially if there are no alternative livelihood options, yet
may be the only way to sustain the fi shery. As in all such matters, political will,
backed by public support and built on a foundation of good science are critically
important for success (Sale et al. 2005 ) . It was with an eye fi rmly on the need for
good science and understanding that this book was conceived.
13.2 What the Chapters Say
We summarize the major fi ndings presented in the chapters of this book, highlighting
when the authors have arrived at general principles previously unrecognized, or
provide a new level of understanding of some aspect of aggregations. We then
identify key research needs, discuss promising areas to explore, and refl ect on
specifi c management and conservation implications. For literary citations, please
refer to original chapters.
A fi rst important step is to clearly defi ne what we mean by the term ‘spawning
aggregation’. To be useful, the defi nition has a clear ecological, biological and practical signifi cance. The tone for this book is set by Michael Domeier in Chap. 1 in
which the defi nition is clarifi ed as a “unique phenomenon of behavioural ecology
where an entire sub-population of individuals halt their normal routine, migrate,
gather and spawn”, with more specifi c guidance given below. The need for a straightforward defi nition applicable to nearly all situations is considerable, as confusion
about what is and is not a spawning aggregation has at times prevented a realistic
13 Conclusion
spawners, aggregations are less likely to be present where fi shing pressure is high.
For example, in the Philippines and Indonesia, both intensively fi shed and with very
little fi shery management, few aggregations have been reported relative to the number
of fi sher interviews conducted (SCRFA country reports: www.SCRFA.org ). On the
other hand, in the western and central Pacifi c, where fi shing pressure is increasing
but is overall considerably more moderate, there are many reports of aggregations,
particularly in the lesser fi shed areas (Sadovy de Mitcheson et al. 2008 ) . We also
know that management can restore depleted aggregations. Such observations suggest
that (1) healthy aggregations are associated with healthy fi sheries, (2) it is important
and possible to proactively manage remaining aggregations and (3) aggregations
might prove to be useful indicators of fi shery condition.
As scientists we take the long view, a necessity when so many fi sh populations
and reefs in general are deteriorating (e.g. Wilkinson 2008 ) . Fish populations can
eventually recover from overfi shing provided the right management environment is
available and the species is not critically depleted. However, it is possible that biological or physiological factors may slow or even stall recovery at low population
sizes, as has evidently been the case for Atlantic cod (Rowe and Hutchings 2003 ) ,
signalling that we cannot wait until the last minute (i.e. numbers of animals have
been much reduced) before we act, and still assume recovery is inevitable. In
extreme cases, this may mean total closure of a fi shery. Such a drastic measure may
have recreational and commercial fi shers up in arms, and will almost certainly be
politically challenging, especially if there are no alternative livelihood options, yet
may be the only way to sustain the fi shery. As in all such matters, political will,
backed by public support and built on a foundation of good science are critically
important for success (Sale et al. 2005 ) . It was with an eye fi rmly on the need for
good science and understanding that this book was conceived.
13.2 What the Chapters Say
We summarize the major fi ndings presented in the chapters of this book, highlighting
when the authors have arrived at general principles previously unrecognized, or
provide a new level of understanding of some aspect of aggregations. We then
identify key research needs, discuss promising areas to explore, and refl ect on
specifi c management and conservation implications. For literary citations, please
refer to original chapters.
A fi rst important step is to clearly defi ne what we mean by the term ‘spawning
aggregation’. To be useful, the defi nition has a clear ecological, biological and practical signifi cance. The tone for this book is set by Michael Domeier in Chap. 1 in
which the defi nition is clarifi ed as a “unique phenomenon of behavioural ecology
where an entire sub-population of individuals halt their normal routine, migrate,
gather and spawn”, with more specifi c guidance given below. The need for a straightforward defi nition applicable to nearly all situations is considerable, as confusion
about what is and is not a spawning aggregation has at times prevented a realistic