Developing strategies to reduce shark mortality in local and high seas fisheries
The incidental capture of sharks in commercial fisheries targeting tuna and billfish is having a negative impact on pelagic shark populations. Due to finning bans most sharks are no longer retained and are discarded at sea. Recent studies have shown that some shark species sustain high levels of post release mortality due to injuries incurred during the fishing interaction. Researchers have identified the three main factors that lead to mortality in sharks; 1) the physiology of the species where some are more susceptible to the lethal effects of stress, 2) the duration of the interaction and 3) the methods used to release the animal. Our research focus is on identifying the underlying behaviors and environmental conditions that lend species vulnerable to fisheries capture to inform conservation engineering efforts and management measures. Currently we are collaborating with the Pacific Islands Regional Observer Program (PIROP) and local commercial fishers to quantify post release mortality rates and assess the effects that handling and discard practices have on release condition and survivability of sharks captured in the Hawaii and American Samoa-permitted tuna longline fisheries and in local small-scale tuna and billfish fisheries.