Once again we discover that the
fishery responds wonderfully to a real regulatory regime. That the fishermen cannot organize them
selves in the first place is unfortunate.
That they actually could has been proven often. You merely select a geographic area for
fishery management and organize all stakeholders and make it a priority to optimize
it all.
Seine nets were banned decades
ago in the Great Lakes because they were
clearly stupid. In time that fishery
will be huge although plenty needs to be done.
At least today, every country has
organized the scientists to measure and make recommendations. This means that ignorance is fast
disappearing and behind it we get improving husbandry. So this story is telling us a very optimistic
tale. Science came, science saw, science
conquered. Perhaps we need to stop
taking those negative stories seriously at all.
by Staff Writers
Dr. Caleb McClennen, Director of the Wildlife Conservation Society's
Marine Program, said: "This important comparison of various fisheries
management systems over time demonstrates the critical need to move past
unregulated open-access fishing in resource poor countries around the world.
This empirical evidence demonstrates how both fishers and their
supporting ecosystems can
and do benefit from restrictions and improved management,"
Marine conservationists from the Wildlife Conservation Society working in
During a 10-year study, conservationists recording fish catches found
that the implementation of fishing regulations-and particularly the banning of
small-mesh seine nets that indiscriminately capture all fish-allowed
practically all fish species to recover, especially those species that took
longer to reproduce.
Fish communities in regulated sites also had a greater diversity of
predatory fish species and those with longer life spans. Even in unregulated
areas there were small improvements to the fish community.
The study appears in the February print version of Fisheries Management
and Ecology.
The authors of the study include Dr. Tim McClanahan of the Wildlife
Conservation Society and Christina Hicks of James
Cook University
in Australia .
The study examined the effects of increasing fisheries management and
fishing gear restrictions in 11 coral reef sites along the 75-kilometer stretch
of Kenyan coast around the city of Mombasa
for a 10-year period.
The wholesale removal of fine-mesh seine nets was implemented in six
sites to the south of Mombasa ,
all of which were more than 30 kilometers away from areas closed to fishing. Kenyatta Beach -a landing site and
popular tourist destination near Mombasa Marine National Park-served as the study's
most intensively regulated site.
The northernmost sites, where fishermen continued to use seine nets in
spite of restrictions, were within five kilometers of the fisheries closure
zones. In addition to seine nets, other types of gear examined in the study
were traps, lines, regular nets, and spears.
"The study shows that regulating coastal fisheries allows fish
populations to recover in a number of predictable ways that correspond with
knowledge of the biology and
ecological characteristics of individual species, but also that the recovery
was faster then predicted for some species," said Dr. Tim McClanahan, WCS
Senior Conservationist and head of the society's coral reef research and
conservation program.
From February 1998 to August 2007, researchers identified and measured
individual fish from 152 species caught at each of the 11 sites-with 15 species
representing approximately 90 percent of the data pool-as well as recording the
gear used.
On average, all fish species from regulated sites over the course of
the study increased in body length over time, with two species-the rabbitfish
(averaging a short lifespan of 5.9 years) and seagrass parrotfish (averaging a
intermediate lifespan of 7.7 years)-exhibiting the most significant size
increases following fishing regulations.
The unregulated northern sites were dominated by short-lived
herbivorous species and the very few species that were able to escape the gaps
of small-meshed nets.
Predictably, the largest and longest lived fish were landed at the most
regulated site (Kenyatta), and the smallest in the least regulated. Further,
spears and gill nets caught the largest fish in the study, whereas the smallest
were caught in seines and lines. Also, fish body lengths in the sites where
seine net bans were implemented and enforced during the study were growing to
the same lengths as fish from the most regulated site by the end of the study.
Dr. McClanahan said the improvements even in the unregulated areas
suggest that strong management can improve conditions in adjacent areas where
management is weak.
"This can lead to either free loading on the nearby stronger
management or increased interests in participating in the improved management,
depending on the interests, incentives, and organization of the fishing and
management community," McClanahan said.
The study builds on a previous WCS study from the same sites on the
costs and revenues of local fisheries along the coast of Kenya , which was published last
year in Conservation Biology and demonstrated that effective fisheries
management actually yields more profits for fishermen. In terms of income,
fishermen working in Kenyatta experienced a 60 percent increase in revenue
(from 224 up to 374 Kenya
shillings, or $3 up to $5) following the beach seine ban in 2001.
By contrast, daily income in the northern sites averaged $2 per person
between 2002-2007. Overall, fishing revenue in the southern landing sites (all
of which banned beach seines during the study period) was 41 percent higher
than northern coast sites with the beach seines; Kenyatta's fishing revenue
climbed to 135 percent higher than northern sites after seine elimination.
Dr. Caleb McClennen, Director of the Wildlife Conservation Society's
Marine Program, said: "This important comparison of various fisheries
management systems over time demonstrates the critical need to move past
unregulated open-access fishing in resource poor countries around the world.
This empirical evidence demonstrates how both fishers and their supporting
ecosystems can and do benefit from restrictions and improved management."
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