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Illuminated nets were tested to evaluate their effect on catch and bycatch in set nets, principally green (Chelonia mydas) and loggerhead (Careta caretta) sea turtles, in northern Cyprus. Reductions in the catch of sea turtle and non-target sharks and rays were recorded with no effect on target catch. Data were collected from 130 field sets that occurred over a two-year period. Experimental effort should be expanded to better ascertain the relationship between the illuminated devices used and sea turtle bycatch reduction.

Illuminated nets were tested to evaluate their effect on catch and bycatch in set nets, principally green (Chelonia mydas) and loggerhead (Careta caretta) sea turtles, in northern Cyprus. Reductions in the catch of sea turtle and non-target sharks and rays were recorded with no effect on target catch. Data were collected from 130 field sets that occurred over a two-year period. Experimental effort should be expanded to better ascertain the relationship between the illuminated devices used and sea turtle bycatch reduction.

Two dolphin click detectors (F-PODs) were placed in two artisanal gillnets in Claromecó (Buenos Aires province, Argentina). Narrowband high-frequency (NBHF) clicks were found near both gillnets, compatible with the description of the franciscana (Pontoporia blainvillei) sound production. These preliminary results confirm that passive acoustic monitoring is a good tool to assess franciscana presence.

 This study aims to provide a comprehensive assessment of the acoustic capabilities of the franciscana (Pontoporia blainvillei). The authors examined the detailed acoustic signals of franciscana dolphins, and compared the sounds from rehabilitated dolphins in captivity with those of wild dolphins near fishing nets. Significant differences in acoustic characteristics were found between neonates and older dolphins, with juvenile and wild dolphins showing similar features. For the first time, repetition patterns in click production were identified, highlighting the importance of understanding the context of these sounds in regards to feeding and communication. This study emphasizes the need for detecting neonates for species protection and suggests the potential for developing acoustic classifiers specific to different age groups. 

Pearl Nets, a passive acoustic deterrent, were tested in commercial gillnet fisheries in the Western Baltic Sea. Compared to a control, the Peal Nets reduced harbor porpoise (Phocoena phocoena) bycatch and maintained target catch rate for Atlantic cod (Gadus morhua).

Surveys and data sources were used to investigate overlap of migrating humpback whales (Megaptera novaeangliae) and both the Western Rock Lobster Fisheries and Developmental Octopus Fisheries off the coast of Western Australia, and to investigate gear modifications to mitigate entanglement. Modifications were made to float rigs (rope type, rope length, and number of floats used), but effectiveness was not assessed within this project. Preliminary results showed that whales are more likely to become entangled in ropes that are thinner, mainlines that are yellow or orange, and orange header rigs. Acoustic pingers were also trialed, but demonstrated no impact on humpback whale behavior; however, the results were inconclusive due to environmental conditions.

This study assessed the frequency and spatio-temporal variation of previously unreported killer whale (Orcinus orca) interactions/depredation with blue-eye trevalla (Hyperoglyphe antarctica) longline fisheries in two geographically isolated populations: one off Amsterdam/St. Paul Islands and another in south-eastern Australia. This two fisheries differ in fishing technique (vertical vs. demersal longlines) and effort. Results from 2010-2016 show that the probability of killer whale interactions in south-eastern Australia decreased in spring and with distance traveled by the vessel between fishing days, but increased with daily fishing effort. In Amsterdam/St. Paul, killer whale interactions increased with latitude. 

This summary study used hierarchical Bayesian modeling to quantify the relationship between entanglement injury/severity with North Atlantic right whale (Eubalaena glacialis) survival, reproduction and population health. Results show that entanglement negatively affects both reproductive and non-reproductive groups, compromises individual health even when gear is not present, reduces survival (especially in females), and reduces fecundity in females that do survive. 

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 study was a controlled experiment within in a harbor that investigated the effectiveness of attaching small, reflective objects (8mm wide acrylic glass spheres) to standard gillnets to increase acoustic reflectivity and therefore mitigate bycatch of small, echolocating cetaceans. The study found that the spheres increased the acoustic backscattering strength and echo, which suggests that the spears would be an effective way to reduce small cetacean bycatch. Gillnets with sphere-sphere distance of 20cm performed best.