This article reviewed bycatch mitigation methods that rely on sensory ecology to reduce interactions with sea birds, sea turtles, pinnipeds and blue-water fish. Panels containing patterns of low spatial frequency and high internal contrast can be used for all of these species. These panels are not likely to reduce catches of target species and are […]
March 2024
Behavioral responses of Sotalia fluviatilis (Cetacea, Delphinidae) to acoustic pingers, Fortaleza, Brazil | Consortium for Wildlife Bycatch Reduction
Underwater acoustic pingers were tested in Brazil to evaluate the behavioral responses of tucuxi (Sotalia fluviatilis). Five pingers were evenly placed on a floating 100 m line set along the dolphins’ swimming parth in and out of sheltered waters. Dolphin sighting frequencies were recorded for functional and dummy pingers and control trials. Dolphin sightings were […]
Pingers as deterrents of bottlenose dolphins interacting with trammel nets | Consortium for Wildlife Bycatch Reduction
The experiment tested the effects of Aquamark 100 pingers on the depredation rate of bottlenose dolphins on trammel nets. Results showed nets equipped with pingers had 87% fewer holes (attributed to damage by dolphins) than nets without pingers.
Can acoustic deterrent devices reduce by-catch in the Cornish inshore gillnet fishery? | Consortium for Wildlife Bycatch Reduction
A study was conducted aboard the Cornish inshore gillnet fishery to determine if pingers could reduce porpoise and bottlenose dolphin bycatch, whether habituation to the pingers would reduce their effectiveness and how quickly porpoises and dolphins recolonise a pingered site after their removal. Vessels were equipped with passive acoustic monitoring systems that can recognize and […]
Conflict between dolphins and a data-scarce fishery of the European Union | Consortium for Wildlife Bycatch Reduction
The study combined fisher questionnaires, acoustic monitoring, and participatory experiments to investigate the occurrence of bottlenose dolphins (Tursiops truncates) in the gillnet fisheries of Northern Cyprus. Dolphins were present in fishing grounds throughout the year, and were detected at 28% of net sets. Net damage was six times greater when dolphins were present during sets. […]
Articles | Consortium for Wildlife Bycatch Reduction
O’Connell, C.P., Abel, D.C., Stroud, E.M. and Rice, P.H., Analysis of permanent magnets as elasmobranch bycatch reduction devices in hook-and-line longline trials, Fishery Bulletin , v. 109, 2011 , ps 394-401 Ocean Watch Australia, Hoppers in Australian Trawl Fisheries – A handbook for fishers, Fisheries Research Development Corporation Australian Government , v. 2003/012, 2004 Ochi, […]
The effects of acoustic alarms on the behavior of harbor porpoises (Phocoena phocoena) in a floating pen | Consortium for Wildlife Bycatch Reduction
Two porpoises were subjected to 3 different underwater sounds (standard Dukane alarm, random Dukane alarm, and a “bird alarm”) in a enclosed floating pen. Their behavior during a 15 min test period was compared to behavior during a baseline 15 min period before the test and a recovery period after the test. All alarms resulted […]
Dolphin Wall Net (DWN) – an innovative management measure devised by ring seine fishermen of Kerala-India to reducing or eliminating marine mammal-fishery interactions | Consortium for Wildlife Bycatch Reduction
Information on the use of Dolphin Wall Nets (DWN) by fisherman in Kerala, India was presented in this paper. The DWN was designed by these fishermen to reduce dolphin attacks during fishing operations. Specifically humpbacked dolphins tend to congregate in fishing areas, surrounding the ring seine net and removing fish from the net. This net […]
A simple technical measure to reduce bycatch and discard of skates and sharks in mixed-species bottom-trawl fisheries | Consortium for Wildlife Bycatch Reduction
A study was conducted to determine the impact of removing the ‘tickler’ from in front of groundgear of trawls. The ‘tickler’ is a length of chain placed in front of the groundgear of trawl gear, which is supposed to increase catches of sharks and rays. Tests were conducted where the ‘tickler’ was removed and secondary […]
An illuminating idea to reduce bycatch in the Peruvian small-scale gillnet fishery. | Consortium for Wildlife Bycatch Reduction
Researchers deployed LED lights on the floatlines of paired gillnets (control vs illuminated net) during 864 fishing sets by small-scale vessels departing from three Peruvian ports between 2015 and 2018. Bycatch probability per set for sea turtles, cetaceans and seabirds as well as catch per unit effort (CPUE) of target species were analyzed for illuminated […]
Selective characteristics of a shark-excluding grid device in a Mediterranean trawl | Consortium for Wildlife Bycatch Reduction
Trials were conducted using excluder grids on trawls targeting Norway lobster (Nephrops novegicus) and greater forkbeard (Phycis blennoides) in the Tyrrhenian Sea. The excluder grids were tested for their ability to reduce the incidental capture of blackmouth catshark (Galeus melastomus). In order to estimate the number of escaped fish, covers were placed over the escape […]
Effective factors of tori-poles in reducing incidental catch of seabirds in the Japanese longline fishery | Consortium for Wildlife Bycatch Reduction
Four parts of the tori-pole were tested for their effectiveness in reducing the incidental catch of albatross in the Japanese southern bluefin tuna longline fishery. Observer data were used to test 1. bird line material, 2. streamer material, 3. bird line length and 4. pole height above sea surface. The effectiveness of tori-poles in reducing […]
Electrochemical properties of lanthanide metals in relation to their application as shark repellents | Consortium for Wildlife Bycatch Reduction
Tests with lanthanide metals were conducted to determine their potential application as a shark repellent in longline fisheries. Six lanthanide metals were tested (cerium (Ce), neodymium (Nd), praseodymium (Pr), cerium-lanthanum mischmetal (CeLa), praseodymium neodymium metal alloy (PrNdA) and praseodymium neodymium mischmetal (PrNdM)) to quantify their voltage and compare dissolution rates in seawater. A behavioral study […]
Mitigating Seal Interactions in the SRLF and the Gillnet Sector SESSF in South Australia | Consortium for Wildlife Bycatch Reduction
Bycatch of Australian sea lions in rock lobster and shark gillnet fisheries is a key threat to the species. This report outlines and assesses methods for mitigating bycatch in these fisheries in South Australia. Gear modification was considered in the rock lobster fishery and spatial closures in the shark gillnet fishery. Spikes of different heights […]
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