577
13 Conclusion
Bahamas after the economic turndown of 2008), or when some recovery is apparent.
Ultimately it seems likely that aggregations should be permanently closed to
commercial fi shing so as to persist as sources of productive fi sheries (through the
eggs produced) rather than being targets of fi shing. The wider issue of the economic
benefi ts of healthy aggregations for the non-aggregation fi shery, therefore, should
become the major consideration in fi sheries assessment and planning, rather than
exploitation of aggregations themselves.
One major reason for regularly surveying aggregations is to determine with
confi dence whether aggregation sizes have changed or remain stable as a result of
management. The very real challenge of collecting rigorous information from aggregations is widely unappreciated; it is costly and requires well-trained, committed and
informed workers to regularly and consistently conduct underwater surveys on
aggregations or to meaningfully sample associated fi sheries. Often diving must be
done under diffi cult physical conditions. Large concentrated groups of fi sh that
briefl y form at deep sites and move around are diffi cult to count with precision/
accuracy and such work can be frustrating, and even dangerous. Moreover, it must
be done over certain periods of the year to be consistent and provide comparable
data on fi sh numbers and horizontal extent of aggregations. For transient aggregations, for example, several days may need to be monitored because fi sh numbers
change daily and there may be some variability in the day of the lunar month that
peak numbers appear in relation to lunar cycle. As we learn more about how to work
with aggregations and aggregating species, the methodology is improving and more
workers are gaining the necessary experience and training for conducting surveys
and research. Nonetheless, such monitoring will continue to be a somewhat specialized activity and frequent updating and retraining should be part of any serious
long-term monitoring programme to ensure consistency and rigour. While local
community involvement is often a critically important aspect of such programmes
and should continue to be so, meaningful underwater monitoring is typically not
streamlined enough to exclude the involvement of expert oversight.
To illustrate some of the challenges, two specifi c examples of monitoring of transient aggregating species will serve. In Palau, the Ebiil spawning site has been studied
on and off since the mid-1990s, most intensively in the 2000s. However, for many of
these years, the full extent of the aggregation site was not known because the area
was not surveyed or marked out. This resulted for many years in the exclusion of a
deeper zone where the third of the three species initially reported, the camoufl age
grouper, was found to spawn. The earlier exclusion of this deeper area from regular
monitoring led to a false conclusion that it had been entirely lost from the site.
Following an intensive season and mapping of the site with expert input, a robust
monitoring protocol was introduced and documented to allow for future replication
(Palau Conservation Society 2010 ) . In Belize, many of the Nassau grouper aggregation sites have been surveyed since 2003. However, dive teams change over time,
retraining in the original methodology is not routinely conducted, details of sampling
not fully documented (such as areas surveyed and how counts were conducted), and the
horizontal extent of some of the surveyed sites are not known. This situation has led to
a review of the procedures since the maximum counts recorded were, in some cases,
the maximum number of fi sh actually seen rather than the peak numbers at the site
13 Conclusion
Bahamas after the economic turndown of 2008), or when some recovery is apparent.
Ultimately it seems likely that aggregations should be permanently closed to
commercial fi shing so as to persist as sources of productive fi sheries (through the
eggs produced) rather than being targets of fi shing. The wider issue of the economic
benefi ts of healthy aggregations for the non-aggregation fi shery, therefore, should
become the major consideration in fi sheries assessment and planning, rather than
exploitation of aggregations themselves.
One major reason for regularly surveying aggregations is to determine with
confi dence whether aggregation sizes have changed or remain stable as a result of
management. The very real challenge of collecting rigorous information from aggregations is widely unappreciated; it is costly and requires well-trained, committed and
informed workers to regularly and consistently conduct underwater surveys on
aggregations or to meaningfully sample associated fi sheries. Often diving must be
done under diffi cult physical conditions. Large concentrated groups of fi sh that
briefl y form at deep sites and move around are diffi cult to count with precision/
accuracy and such work can be frustrating, and even dangerous. Moreover, it must
be done over certain periods of the year to be consistent and provide comparable
data on fi sh numbers and horizontal extent of aggregations. For transient aggregations, for example, several days may need to be monitored because fi sh numbers
change daily and there may be some variability in the day of the lunar month that
peak numbers appear in relation to lunar cycle. As we learn more about how to work
with aggregations and aggregating species, the methodology is improving and more
workers are gaining the necessary experience and training for conducting surveys
and research. Nonetheless, such monitoring will continue to be a somewhat specialized activity and frequent updating and retraining should be part of any serious
long-term monitoring programme to ensure consistency and rigour. While local
community involvement is often a critically important aspect of such programmes
and should continue to be so, meaningful underwater monitoring is typically not
streamlined enough to exclude the involvement of expert oversight.
To illustrate some of the challenges, two specifi c examples of monitoring of transient aggregating species will serve. In Palau, the Ebiil spawning site has been studied
on and off since the mid-1990s, most intensively in the 2000s. However, for many of
these years, the full extent of the aggregation site was not known because the area
was not surveyed or marked out. This resulted for many years in the exclusion of a
deeper zone where the third of the three species initially reported, the camoufl age
grouper, was found to spawn. The earlier exclusion of this deeper area from regular
monitoring led to a false conclusion that it had been entirely lost from the site.
Following an intensive season and mapping of the site with expert input, a robust
monitoring protocol was introduced and documented to allow for future replication
(Palau Conservation Society 2010 ) . In Belize, many of the Nassau grouper aggregation sites have been surveyed since 2003. However, dive teams change over time,
retraining in the original methodology is not routinely conducted, details of sampling
not fully documented (such as areas surveyed and how counts were conducted), and the
horizontal extent of some of the surveyed sites are not known. This situation has led to
a review of the procedures since the maximum counts recorded were, in some cases,
the maximum number of fi sh actually seen rather than the peak numbers at the site