Acoustic pingers eliminate beaked whale bycatch in a gill net fishery
Published source details
Carretta J.V., Barlow J. & Enriquez L. (2008) Acoustic pingers eliminate beaked whale bycatch in a gill net fishery. Marine Mammal Science, 24, 956-961
Published source details Carretta J.V., Barlow J. & Enriquez L. (2008) Acoustic pingers eliminate beaked whale bycatch in a gill net fishery. Marine Mammal Science, 24, 956-961
This study is summarised as evidence for the following.
Use acoustic devices on fishing gearAction Link
Use acoustic devices on fishing gear
A before-and-after study in 1990–2006 of multiple pelagic sites in the North Pacific Ocean, off the coasts of California and Oregon, USA (Carretta et al. 2008; same fishery as Barlow & Cameron 2003 and Carretta & Barlow 2011) found that using acoustic devices on fishing nets reduced the number of beaked whale (Ziphiidae) entanglements. No beaked whales were found entangled in fishing nets during the 11 years in which acoustic devices were used, whereas 33 whales of at least six species were entangled during the six years before the devices were used (see original paper for details). In 1990–1995, a total of 3,303 nets were deployed without acoustic devices. In 1996–2006, a total of 4,381 nets were deployed with acoustic devices attached at 91 m intervals (average 40 devices/net). The devices emitted 300 ms pulses at 10–12 kHz. Each of the 7,684 ‘drift’ gill nets (1,800 m long x 65 m deep) was deployed from dusk until dawn at depths of 11–90 m to catch swordfish and sharks. Observations of entangled whales were made by biologists on board fishing vessels in 1990–2006.
(Summarised by: Anna Berthinussen)