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This research investigates the overlap of potentially illegal longlining efforts and their effects on the average risk of albatrosses. Results indicate that albatrosses are at particularly higher risk in areas where illegal longlining vessels are found, and that those vessels are spatially concentrated to areas of the highest concentrations of CRAAVED (concealable, removable, abundant, accessible, valuable, enjoyable, disposable) fish species.

This is a summary of case studies that were reviewed for efficacy of mitigation methods in gillnet fisheries for reducing seabird bycatch, focusing specifically on time-area restrictions and gear-switching. Both methods show promise to reduce bycatch and meet conservation standards, but a holistic approach that considers seabird behavior, target species  activity, and socioeconomic impacts is encouraged. Combining these methods with other measures (e.g., time-area fishing restrictions, gear-switching, visual and acoustic deterrents) may be feasible and effective in areas where if fine-scale
spatial and temporal information about seabirds and gillnet fisheries is available. 

Seabird bycatch in gillnets is a worldwide problem with few if any available mitigation tools. LED lights attached to the gillnets have been suggested as a potential solution, and a study in Peru showed promising results where bycatch of diving seabirds was reduced by adding LED lights to bottom set gillnets. In this study the potential bycatch reduction of LED lights was tested in a set gillnet fishery that targets Atlantic cod Gadus morhua in Iceland. A variety of seabirds such as common guillemots, cormorants, eiders, northern gannets, northern fulmars, and gulls have been observed as bycatch in that fishery. In a paired trial, nets with and without LEDs were fished off a commercial gillnetter in western Iceland. The LED-equipped net sets caught significantly more seabirds while a slight but statistically insignificant reduction in fish catches was also observed. The seabirds caught in the LED-equipped nets were mainly northern gannets and northern fulmars, plunge- and surface-feeding birds, which seemed to be attracted to the lights while hauling and setting the nets. Caution should be taken when implementing the use of LED lights on gillnets or trawls as while they might reduce bycatch of some taxa of diving seabirds or sea turtles, it is possible that some bird species or groups of bird species are attracted to the lights, in particular during hauling and setting of the nets.

The present field study investigated reducing common eider bycatch in the West Greenland lumpfish gillnet fishery by a gear modification of adding a 45 cm high small-meshed net panel to the bottom part of nets. The study was trialed in the field, first in a controlled setting and then by commercial fishers, between 2021 and 2022. The modified nets displayed a 71% reduced bycatch rate for common eider and a 25% reduced catch rate for the target female lumpfish.
 

This study experimented with the use of Looming-Eye Buoys (LEBs) attached to gillnets in the Icelandic lumpfish fishery to reduce seabird bycatch, and experiments took place in spring 2022. LEBs are intended to be a visual deterrent that mimics a predator's eyes. The LEBs did not have a significant impact on target catch or bycatch, but results suggest a strong correlation between seabird bycatch and depth; the authors estimate that limiting fishing to waters below 50m deep could save between 5000 and 9300 seabirds every year.

 The present study tested LED lights in paired trials of a commercial gillnet fishery targeting Atlantic cod (Gadus morhua) in Iceland, due to previous studies that suggest attaching LED lights to gillnets to reduce seabird bycatch. The LED-equipped sets actually caught significantly more seabirds (mainly northern gannets and northern fulmars), and slightly (but statistically insignificant) reduced fish catch. While the use of LED lights on gillnets may reduce bycatch of some species, some bird species appear to be attracted to the lights.

Seabird bycatch in gillnets is a worldwide problem with few if any available mitiga-
tion tools. LED lights attached to the gillnets have been suggested as a potential solution, and a
study in Peru showed promising results where bycatch of diving seabirds was reduced by adding
LED lights to bottom set gillnets. In this study the potential bycatch reduction of LED lights was
tested in a set gillnet fishery that targets Atlantic cod Gadus morhua in Iceland. A variety of sea-
birds such as common guillemots, cormorants, eiders, northern gannets, northern fulmars, and
gulls have been observed as bycatch in that fishery. In a paired trial, nets with and without LEDs
were fished off a commercial gillnetter in western Iceland. The LED-equipped net sets caught sig-
nificantly more seabirds while a slight but statistically insignificant reduction in fish catches was
also observed. The seabirds caught in the LED-equipped nets were mainly northern gannets and
northern fulmars, plunge- and surface-feeding birds, which seemed to be attracted to the lights
while hauling and setting the nets. Caution should be taken when implementing the use of LED
lights on gillnets or trawls as while they might reduce bycatch of some taxa of diving seabirds or
sea turtles, it is possible that some bird species or groups of bird species are attracted to the lights,
in particular during hauling and setting of the nets.

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 successfully detered seabirds during fishing operations, especially within the closest 20m from the vessel, where there was a significant reduction in yellow-legged and lesser black-backed gull (Larus michahellis and L. 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 study utilized onboard observations and fishermen interviews to investigate seabird seasonal abundance and interactions with artisanal bottom-set net fisheries off the southern-eastern coast of mainland Portugal between 2020 and 2022. 25 species of seabirds were recorded as bycatch, with lesser black-backed and Yellow-legged gulls
(Larus fuscus and Larus michahellis) the most abundant. Great shearwaters (Ardenna gravis) were caught more frequently in trammel nets during autumn, suggesting effects of both season and gear type. Fishermen interviews identified Northern gannets and Great cormorants (Phalacrocorax carbo)
as the most frequently bycaught species,