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The authors performed modeling on 10 years of logbook data to analyze environmental and operational factors that influence shark and odontocete depredation in the New Caledonian longline tuna fishery. Results suggest that there are "hotspots" of odontocete depredation, and that it is driven by environmental factors such as sea surface temperature and bathymetry, while shark depredation is driven by operational fisheries factors such as soaking time and number of hooks. Alterations such as reducing soaking time to under 12 hours, or setting limits on hooks to <1,750, could significantly reduce the likelihood of depredation. 

The authors developed a novel mitigation method for reducing seabird bycatch in gillnet fisheries in the Baltic Sea: looming-eyes buoys (LEB), an above-water visual deterrent. This method was trialed off of Sareemaa Island, Estonia, and was shown to reduce potential for long-tailed duck (Clangula hyemalis) bycatch by 20-30% within a 50m radius with a possible habituation effect within 62 days. These trials suggest that above-water visual deterrents such as LEBs could contribute to reduce seabird bycatch in combination with other management and mitigation measures. 

The authors tested the effectiveness of using green light emitting diodes (LEDs) on demeral, set gillnets in Constante, Peru as a visual deterrent to reduce seabird bycatch. When comparing illuminated nets to control nets, seabird bycatch was significantly lower and represented an 85.1% decline in guanay cormorant ((Phalacrocorax bougainvillii) bycatch. Target catch was not affected, suggesting that this mitigation technique may be an effective mitigation method for seabirds, the same way it seems to be effective for reducing sea turtle bycatch.

The authors tested the effectiveness of 'scarybird', a visual deterrent, to reduce seabird bycatch in bottom gillnet fisheries in Portugal. The scarybird is a raptor-shaped aerial device that is flown behind the stern of the boat up to  ~7m above sea level. The scarybird did successfully deter seabirds during fishing operations, especially within the closest 20m from the vessel where there was a significant reduction in gulls (Larus michahellis/fuscus, −56 %) and northern gannets (Morus bassanus, −72 %). Target catch was not affected, suggesting this mitigation measure could be an easily implementable device for any fishery gears where bird interactions occur close to the surface.

This paper suggests guidelines for evaluating artificial light in bycatch reduction devices (BRL) using a standardized, collaborative, multidisciplinary approach. The purpose is to improve data consistence to support future meta-analyses and inter-study comparisons, and to highlight areas where further research is needed most urgently, as BRLs are a promising and rapidly moving area of bycatch mitigation.