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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. Humpback whales responded to 'tones' by moving offshore and surfacing more often, perhaps trying to avoid the stimuli. These changes were related to the proximity to the source, the received signal level and signal to signal noise ratio. When social sounds were used the responses were very variable and dependent on the groups composition. This study indicates that behavioral responses of marine mammals to acoustic stimuli is complex and in need of additional research.

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. For the 45 cases in which parts of the gear were retrieved, entanglements occurred in buoy line and/or groundline (49%), in float and surface system lines (11%), with 40% of cases in which the gear components were unknown. Right whales were most commonly entangled in the mouth (77.4%), while humpback whales were frequently entangled in both the mouth (43%) and tail (53%). Continued studies of entanglement are needed to provide additional insight.

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. The DTAGs are non-invasively deployed and record all sounds at a sampling rate of 32 kHz, a Nyquist rate of 16 kHz and records the pitch, roll, heading and depth of the whale at a sampling rate of 46 Hz. Whales showed a strong reaction to the alert signal, swimming strongly to the surface. Whales showed a mild response to social sounds and no response to sounds of an approaching vessel. The response to the alert signal would more likely result in an increased risk of collision and not a decreased risk.

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. The DTAGs are non-invasively deployed and record all sounds at a sampling rate of 32 kHz, a Nyquist rate of 16 kHz and records the pitch, roll, heading and depth of the whale at a sampling rate of 46 Hz. Whales showed a strong reaction to the alert signal, swimming strongly to the surface. Whales showed a mild response to social sounds and no response to sounds of an approaching vessel. The response to the alert signal would more likely result in an increased risk of collision and not a decreased risk.

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). The lobster fishery poses the greatest threat during the spring and summer periods as whales migrate to and from Critical Habitat. Gillnet's pose a considerable gear related threat, 18% of the total threat. 

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). The lobster fishery poses the greatest threat during the spring and summer periods as whales migrate to and from Critical Habitat. Gillnet's pose a considerable gear related threat, 18% of the total threat. 

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). The lobster fishery poses the greatest threat during the spring and summer periods as whales migrate to and from Critical Habitat. Gillnet's pose a considerable gear related threat, 18% of the total threat. 

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. The oscillatory pull abrasion system measured the tissue compliance limit under a shear load and used a series of upper/lower pulleys to position an abrading line across the leading edge of the test sample. Tissues from the leading edge of a flipper for a right whale calf and leading edge of an adult right whale were used during this study. Line furrow patterns were documented through photographs and tissue abrasion was compared using the 1) maximum depth of epidermal/dermal penetration and 2) length of epidermal removal. For the straight pull abrasion test, an adult right whale fluke required 3.7 times the load and 15 times the draw-length of a right whale calf flipper for epidermal failure to occur. The oscillatory abrasion test indicated that line draw-lengths were more than the tissue compliance limit and resulted in substantial increased tissue abrasion. Increasing the line's ability to stretch in response to a load could minimize sliding of the line and help mitigate entanglement injuries.

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. 

A literature review of 30 studies was conducted to determine the  effectiveness of various bycatch reduction devices for elasmobranchs. The risk of capture was 1.2 times higher on circle hooks but haulbaulk mortality as well as deep hooking was reduced. Wire leaders had higher shark catch and haulback mortality rates compared to monofilament. Hooking position is determined by the hook shape and width combined with bait. These characteristics also affect the ability to sever monofilament leaders. Shark catch rates and deep hooking were increased when fish was used for bait compared to squid. Wider hooks resulted in reduced pelagic stingray catch and mortality.