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.

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.

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.

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.