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Shark Depredation and Unwanted Bycatch in ... - ProDelphinus

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<strong>Shark</strong> <strong>Depredation</strong> <strong>and</strong> <strong>Bycatch</strong> <strong>in</strong> Pelagic Longl<strong>in</strong>e Fisheries Page 32<br />

Acoustic deterrents may reduce shark-longl<strong>in</strong>e <strong>in</strong>teractions, but have not been tested <strong>in</strong> longl<strong>in</strong>e fisheries<br />

for any shark species.<br />

7.2. Hotspot Avoidance through Fleet Communication <strong>and</strong> Protected Areas<br />

Fleet communication programs <strong>and</strong> area <strong>and</strong> seasonal closures are management tools that can enable a<br />

longl<strong>in</strong>e fleet to avoid bycatch hotspots that can complement employment of other strategies to reduce<br />

shark bycatch <strong>and</strong> depredation. The distribution of sharks <strong>and</strong> other species groups such as seabirds,<br />

sea turtles <strong>and</strong> cetaceans, is often unpredictable, <strong>and</strong> may be spatially contagious or aggregated.<br />

Consequently, fleet communication systems may be employed by fish<strong>in</strong>g <strong>in</strong>dustry to report near real-time<br />

observations of hotspots to enable a fishery to operate as a coord<strong>in</strong>ated “One Fleet” to substantially<br />

reduce fleet-wide depredation <strong>and</strong> bycatch of sharks (Gilman et al. 2006c). In addition, fleet coord<strong>in</strong>ation<br />

of daily fish<strong>in</strong>g positions <strong>and</strong> times, a current practice <strong>in</strong> many fleets, may m<strong>in</strong>imize per vessel shark<br />

<strong>in</strong>teraction levels relative to vessels that fish <strong>in</strong> isolation (Gilman et al., 2006c).<br />

Area <strong>and</strong> seasonal closures can also contribute to reduc<strong>in</strong>g shark-longl<strong>in</strong>e <strong>in</strong>teractions. Establish<strong>in</strong>g<br />

protected areas with<strong>in</strong> a nation's Exclusive Economic Zone is potentially an expedient method to reduce<br />

shark-longl<strong>in</strong>e <strong>in</strong>teractions. However, establish<strong>in</strong>g <strong>and</strong> manag<strong>in</strong>g high seas mar<strong>in</strong>e protected areas to<br />

protect sharks, which would require extensive <strong>and</strong> dynamic boundaries <strong>and</strong> extensive buffers, may not be<br />

a viable short-term solution. This is due <strong>in</strong> part to the extensive time anticipated to (i) resolve legal<br />

complications with <strong>in</strong>ternational treaties, <strong>in</strong>clud<strong>in</strong>g creat<strong>in</strong>g legally b<strong>in</strong>d<strong>in</strong>g mechanisms for multilateral<br />

designation <strong>and</strong> management of high seas protected areas; (ii) achieve <strong>in</strong>ternational consensus <strong>and</strong><br />

political will; (iii) provide requisite extensive resources for surveillance <strong>and</strong> enforcement, <strong>in</strong> part, to control<br />

illegal, unreported <strong>and</strong> unregulated fish<strong>in</strong>g activities; <strong>and</strong> (iv) improve the scientific basis for design<strong>in</strong>g<br />

high seas mar<strong>in</strong>e protected areas, which can be effective at reduc<strong>in</strong>g shark <strong>in</strong>teractions only where the<br />

location <strong>and</strong> times of occurrence of shark hotspots are known <strong>and</strong> predictable (Gilman, 2001). However,<br />

establish<strong>in</strong>g <strong>and</strong> manag<strong>in</strong>g a representative system of protected area networks on the high seas to<br />

contribute to the management of <strong>in</strong>teractions between mar<strong>in</strong>e capture fisheries <strong>and</strong> highly migratory<br />

sensitive species groups, <strong>in</strong>clud<strong>in</strong>g sharks, may eventually be realized.<br />

Recent developments with<strong>in</strong> the framework of the United Nations Convention on the Law of the Sea <strong>and</strong><br />

associated conventions <strong>and</strong> by several Regional Fishery Management Organizations may make it<br />

possible <strong>in</strong> the near future to establish mar<strong>in</strong>e protected areas on the high seas that restrict fish<strong>in</strong>g<br />

activities that are shown to threaten rare or fragile ecosystems or the habitat of depleted, threatened or<br />

endangered species <strong>and</strong> other forms of mar<strong>in</strong>e life. It is already possible to establish high seas mar<strong>in</strong>e<br />

protected areas for discrete areas by agreement by <strong>in</strong>dividual countries. However, there rema<strong>in</strong>s a need<br />

for an <strong>in</strong>ternational framework with specific language to identify the criteria to establish a representative<br />

system of high seas mar<strong>in</strong>e protected area networks, <strong>and</strong> management <strong>and</strong> enforcement measures for<br />

the <strong>in</strong>dividual mar<strong>in</strong>e protected areas. Several regional fishery management organizations are updat<strong>in</strong>g<br />

their scope <strong>and</strong> legal m<strong>and</strong>ate to <strong>in</strong>clude ecosystem-based management <strong>and</strong> biodiversity conservation<br />

under the auspices of the Fish Stocks Agreement. The Commission for the Conservation of Antarctic<br />

Mar<strong>in</strong>e Liv<strong>in</strong>g Resources has made some prelim<strong>in</strong>ary progress towards establish<strong>in</strong>g a system of mar<strong>in</strong>e<br />

protected areas <strong>in</strong> the Southern Ocean.<br />

Consequences of establish<strong>in</strong>g a protected area need to be carefully considered, as resource use<br />

restrictions of a mar<strong>in</strong>e protected area may displace effort to adjacent <strong>and</strong> potentially more sensitive <strong>and</strong><br />

valuable areas, where weaker management frameworks may be <strong>in</strong> place (Murray et al., 2000; Baum et<br />

al., 2003; Kotas et al., 2004). Also, measures adopted by regional fishery management organizations<br />

<strong>and</strong> other <strong>in</strong>ternational bodies are only b<strong>in</strong>d<strong>in</strong>g to parties to the Convention that established the<br />

organization, <strong>and</strong> will not control activities by non-party States. Thus, another consideration for<br />

employ<strong>in</strong>g high seas mar<strong>in</strong>e protected areas to manage problematic fisheries bycatch is that clos<strong>in</strong>g<br />

areas to fisheries only of party States could result <strong>in</strong> <strong>in</strong>creased effort <strong>in</strong> this area by fleets from non-party<br />

States with fewer or no controls to manage bycatch, exacerbat<strong>in</strong>g the problem for which the MPA was<br />

established to address.

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