Two captive harbor porpoises were exposed to three sound types (frequency from 100 kHz to 140 kHz, 200 ms long, and presented once per 4 s). Each session consisted of a 10 min period persound, a 5 min period of sound, and a 10 min period after the sound. Behavior was recorded on video and […]
May 2024
Hooks equipped with magnets can increase catches of blue shark (Prionace glauca) by longline fishery | Consortium for Wildlife Bycatch Reduction
Pelagic longline hooks equipped with magnets were tested for their ability to repel blue sharks. Tests were conducted aboard pelagic longliners operating in the Northeast Atlantic Ocean. Two magnets, one large and one small, were tested. Magnets were manually attached to the hooks (polarized so the magnet field was oriented N or S and in […]
Review of magnetic shark deterrents: Hypothetical mechanisms and evidence for selectivity | Consortium for Wildlife Bycatch Reduction
A review of recently published articles dealing with the effects of magnetic fields on elasmobranchs and potential use in bycatch avoidance was conducted. The authors suggest these papers ignore that teleosts may also demonstrate magnetite based magnetoreception and that electroreception is present in many teleosts. Based on this, the possibility of induction based indirect magenetoreception […]
How to Use the Database | Consortium for Wildlife Bycatch Reduction
Citations for studies that pertain to bycatch reduction approaches. Summaries of the findings for each study. Descriptions of bycatch reduction techniques. Descriptions of fishing methods. Links to studies and study authors, where available. Users can search the database by fishing gear, bycatch reduction technique, or non-target wildlife group singly or in combination. This is achieved […]
The efficiency of sieve‐panels for bycatch separation in Nephrops trawls | Consortium for Wildlife Bycatch Reduction
This study investigated the efficiency of a sieve‐panel to separate bycatch species from Norway lobster (Nephrops norvegicus) in trawl gear via mechanical and behavioral means. Four different designs of varying panel mesh size or inclination were tested. The sieving efficiency for Nephrops increased from ~17% to ~71% as mesh size increased, and decreased with increasing carapace length, but […]
Analysis of 2004-2007 vessel-specific seabird bycatch data in Alaska demersal longline fisheries | Consortium for Wildlife Bycatch Reduction
Average annual seabird bycatch has declined by 73% in the last 5 years (2002-2006) compared to bycatch from the late 1990s. Despite the recent reductions resulting from mandatory mitigation requirements, seabirds continue to be caught at higher rates than would be expected given results of controlled studies that demonstrated bycatch reductions of nearly 100% with […]
Reactions of Hector's dolphins to acoustic gillnet pingers | Consortium for Wildlife Bycatch Reduction
White Dukane pingers with a fundamental frequency of 10kHz and harmonies of up to 160 kHz, elicited the strongest response from Hector’s dolphins, compared to the black Pice and red Dukane pingers. More than half (62.5%) of the dolphins exhibited avoidance when exposed to the white pinger. However, no significant differences between pingers were found […]
Quantification of interactions between the Portuguese sardine purse-seine fishery and cetaceans | Consortium for Wildlife Bycatch Reduction
A study was conducted on observed interactions between a Portuguese purse-seine fishery and cetaceans. Cetaceans, primarily common dolphins (Delphinus delphis), were present during 16.9% of fishing events. The majority of these occurrences happened during the summer and early fall, and during the night. The presence of cetaceans was significantly linked to sardine catches, effort and […]