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A spatially and temporally explicit Productivity and Susceptibility Analysis (PSA) was developed to screen cetacean species for bycatch risk. This PSA can be included under Ecosystem Based Fisheries Management (EBFM). The potential risk to harbor porpoises and minke whales from static fishing gear was investigated. Harbor porpoise's had a low to moderate biological risk from bycatch compared to other cetacean species. Minke whales are less productive than harbor porpoise's but also have a low to moderate biological risk to bycatch.

This study provides a summary of methods that can be used to reduce depredation and bycatch of marine mammals in longline fisheries. Methods include 1) spatial management methods, 2) acoustic methods, 3) physical methods and 4) 'other methods'. The results indicate that some methods can be used with both pelagic and demersal longlines, while others can be used with only one or the other. In addition to the methods investigated, the results highlight significant knowledge gaps.These include survivability after hooking and entanglement.

This study collected information on cetacean incidents (carcasses, injured and debilitated animals found onshore, entrapped in shallow water, entangled or floating offshore) that have occurred in New South Wales, Australia. Information on marine mammal incidents was reported to the New South Wales National Parks and Wildlife Service and recorded into a Marine Fauna Events Database. This information was analyzed for trends in mortality and population dynamics such as age and sex ratios. Records existed for the time period of 1790 to 2013.

Documented entanglement cases for sea turtles and cetaceans in mussel aquaculture gear worldwide were collected. Online surveys and semi-structured interviews with mussel operators were used in Iceland. A total of seven entanglement reports were collected, four baleen whales, one harbour porpoise and two leatherback sea turtles. Mussel spat collecting ropes were involved in the majority of cases. Out of the seven reports, two occurred in Iceland. The proximity between cetacean distributions and mussel farming sites is likely a factor in these interactions.

The authors investigated several data sources and conducted surveys to identify potential mitigation measures that could be used to reduce humpback whale entanglements in Western Australia (WA). The Cetacean Stranding Database (CSD) and Commercial Whale Watching Database (CWWD), managed by the Western Australia Department of Parks and Wildlife, were both investigated. High occurrences of whale entanglements off the central coast of WA were identified in the CSD.

A quantification of interactions between cetaceans and fishers was conducted in the Atlantic and Indian Oceans. A large database of captains logbooks, 1980-2011, was analyzed along with scientific observer observations recorded between 1995 and 2011. The main areas of high co-occurrence between cetaceans and fisheries was shown to exist east of the Seychelles from December to March, the Mozambique Channel between April and May, and in offshore waster of Gabon between April and September.

Pingers have been used on shark nets set along Queensland's beaches since 1992. Due to an increase in whale entanglements in 2009, new pingers (Fumunda F3 whale pingers and F10 dolphin pingers) were deployed between July and August 2010. Subsequently updated research on the use of these pingers was needed.

A summary study of methods used to reduce or eliminate marine mammal entanglements was conducted. The authors found little evidence on the effectiveness of the use of sound to reduce or eliminate marine mammal incidental capture. Substantial decreases in cetacean bycatch, due to the use of passive methods such as increasing fishing net reflectivity, were not evident through comparisons of catch rates in commercial fisheries or from observational deterrence studies.

This is a compendium of various studies evaluating potential deterrents to large whale entanglements.

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.

This supplement to a 2002 compendium of NOAA large whale entanglement prevention research has newer studies, including investigation of SAM gillnet gear, gillnet weak links and anchoring systems, evaluation of gillnet weak links, and a pilot study of options for reducing vertical line entanglements.

This supplement to a 2002 compendium of NOAA large whale entanglement prevention research provides an overview of recent NMFS gear research and testing of the time tension line cutter.

This report describes a buoyless lobster trap that has an acoustic trigger mechanism. An existing lobster trap would contain all the components except for the transmitter, which consisted of a prototype developed using a Hummingbird Fish Finder.

The purpose of this project was to determine ways to enhance the performance of sinking groundline, involving three approaches: (1) Reviewing previous research and lobstermen’s experience with sinking groundlines; (2) Recording directly from lobster fishermen of the Gulf of Maine the practical challenges they encountered in converting to sinking groundline; (3) Producing visual observations of actively fished sinking groundline to gain insights into chafing and how it might be reduced.

A study was conducted with humpback whales to test their response to recordings of conspecific social sounds and an artificially generated tone stimulus. Experiments were conducted during humpback whales southward migration along the east coast of Australia. A total of 13 tone experiments, 15 social sound experiments and 3 silent controls were conducted during two field seasons (September/October 2004 and 2008). The results indicated that humpback whales respond differently, with respect to course traveled and dive strategy, to the two stimuli.

Entanglements of 31 right whales (Eubalaena glacialis) and 30 humpback whales (Megaptera novaeangliae) in the western North Atlantic were analyzed to identify the parts and types of gear involved. The results indicated that a large number of specific gear types were involved in entanglements. Gear type could not be identified in 20% of entanglements. When gear type was identified, 89% of entanglements were caused by pot and gillnet gear. Pot gear was recovered from both species in equal amounts but gillnet gear was more frequently retrieved from humpbacks compared to right whales.

Risk factors involving ship strikes and North Atlantic right whales were investigated in this study. A multi-sensor digital acoustic recording tag (DTAG) was used to measure the responses of whales to four stimuli: vessel noise, social sounds of conspecifics, and a signal designed to alert whales. Silence was used as the control measure. Testing was conducted in the Bay of Fundy summer foraging region.

Right whale survey data and Canadian fishing gear deployment data were used to estimate the threat of gear entanglement to right whales in the Scotia-Fundy region and the risk of lethal entanglement in the Bay of Fundy and Roseway Basin, Scotian Shelf. The following fisheries were investigated: groundfish and pelagic hook and line, groundfish gillnet, and crab, hagfish and inshore/offshore lobster traps. Groundfish hook and line gear poses the largest threat to right whales during the summer resident period in the Bay of Funday and on Roseway Basin (Critical Habitat).

Two test systems were developed to examine fishing line entanglement injuries in large whales. The systems evaluated straight pull abrasion and oscillatory abrasion in relation to tissue compliance. The straight pull abrasion study was used to measure the depth of epidermal penetration after a unidirectional pull of line over a standard draw-length.

Loggerhead sea turtles have a high-density foraging hot spot in Baja California Sur, Mexico. This spot coincides with intense bottom-set net fisheries. Controlled studies were conducted in Baja California Sur, Mexico between 2007 and 2009 to compare turtle bycatch rates with target catch rates, composition, and market value between control and buoyless nets. A total of 136 controlled sets were made. The results suggest that mean turtle bycatch was reduced by 68% with the use of buoyless nets but target catch rates were not impacted.