maximios

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 […]

Tests were conducted aboard pelagic longline vessels fishing off the coast of Uruguay, to determine the effect of hook type (circle hook vs J-hook) on the catch and length composition of target and non-target species.  Both American and Spanish style longlines were used during these experiments.  American style longlines consist of a 3.6 mm polyamide […]

Catch rates of blue marlin, snake mackerel and sharks were lower when nylon monofilament leaders, instead of wire leaders, were used on pelagic longline gear but bigeye tuna and black marlin catch rates increased. (No effect on yellowfin). Nylon leaders also had higher bite-off rates than the wire leaders.

Analyses of the Hawaiian pelagic longline fishery were conducted to determine what factors, including hook type (J or circle) and location (sea mount v open ocean), have impacted the catch of both target and bycatch species.   Standardized catch rates for all tuna species as well as for blue and oceanic whitetip sharks were significantly […]

In northern hemisphere trawl fisheries, little is known about the extent of cable strike seabird mortality or techniques to mitigate it. We compared the rate of heavy seabird strikes by third-wire cables and warps, using three mitigation measures compared to a control of no mitigation. Experiments were conducted aboard two catcher-processor vessels targeting walleye pollock […]

Bilgin, S. and Köse, Ö., Testing two types of acoustic deterrent devices (pingers) to reduce harbor porpoise, Phocoena phocoena (Cetacea: Phocoenidae), bycatch in turbot (Psetta maxima) set gillnet fishery in the Black Sea, Turkey, Cahiers de Biologie Marine , v. 59(5), 2018 , ps 473-479 Boggs, C.H., Annual Report on the Hawaii Longline Fishing Experiments […]

This study investigated the effect of acoustic pingers on the behavior of Burmeister’s porpoise (Phocoena spinipinnis) in the vicinity of the Peruvian small-scale driftnet fleet. Over a 4-yr period (2009-2012), 116 control (without pingers) and 94 experimental (with pingers) fishing sets were observed, and porpoise acoustic activity around nets was recorded using passive acoustic loggers […]

Crab traps were fitted with a Turtle Excluder device to reduce the incidental capture of diamondback terrapins. No diamondback terrapins were caught during this study but the total catch rate of targeted blue crabs, compared to the standard traps, increased by 25.7% (14.5% sublegal size, 32.9% legal size). The difference in total catch rates and […]

Alternative trap designs were tested to determine their ability to reduce bycatch of ecologically important herbivore species such as parrotfish and surgeonfish. Catches from traditional Antillean chevron traps were compared to catches from traps with 1) short escape gaps (20X2.5 cm), 2) traps with tall escape gaps (40X2.5 cm) and 3) traps with a panel […]

The once-abundant Mediterranean monk seal has been adversely impacted by human activities, ranging from exploitation for fur and oil to habitat fragmentation that have occured over many centuries. Today, one of the greatest threats facing the remaining seals is accidental entanglement in fishing nets. Bycatch mortality occurs throughout the species’ range, and has been increasingly […]

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This supplement to a 2002 compendium of NOAA large whale entanglement prevention research includes newer studies, including evaluation of a time tension line cutter, and studies on neutrally buoyant groundline, load cell field work on gillnets, and recycling of polypropylene rope.

Do circle hooks reduce bycatch?…It depends. Last week, NOAA hosted over 160 marine scientists, fisheries managers, gear experts, and commercial and recreational fishermen, from 20 countries, in Coral Gables, FL, for the first international symposium on circle hooks in research, management and conservation.  While we all came away more informed about circle hooks, we left with more […]

Several versions of a terrapin excluder design were tested on crab traps to determine how effective they were in reducing terrapin bycatch and what the effect on catch rates of targeted crabs was. All tests consisted of modified and unmodified traps being set in an alternate fashion. A wire bar placed across the opening of […]