Acoustic Deterrents (Marine Mammals)

Most bycatch reduction techniques so far implemented around the world have been in commercial fisheries within developed countries, which have relatively strong regulatory and enforcement capacity, and that generally can absorb increased expenses or reduced revenue from regulated modifications to fishing methods.

For several years, the NEAq has been working with local fishermen, the Argentinian NGO AquaMarina, and the Argentine government on collaborative research program with fishermen in northern Buenos Aires Province, Argentina. The goal of this program is to identify practical fishing methods that reduce the unsustainable bycatch of the endangered Franciscana dolphin (Pontoporia blainvillei) in gillnets, while maintaining productive local fisheries. Bycatch of Franciscana dolphins in the artisanal gillnet fisheries of Argentina, Uruguay and Brazil has been observed since at least the early 1940s, and is the primary conservation threat to this species throughout most of its range. Currently, the Franciscana dolphin is listed as Vulnerable by the IUCN and it is considered the cetacean most affected by human activities in the South Western Atlantic.

Major accomplishments to date from our collaborative research:

  • Acoustic deterrents have shown to significantly reduce Franciscana bycatch in multiple trials while maintaining target catch
  • Evaluations of fishing gear other than gillnets—handlines and pots—have demonstrated elimination of bycatch and economic potential for local fishermen
  • Increasing the spacing of pingers can significantly reduce bycatch while also reducing the cost of fishermen to use them
  • Franciscana dolphins do not appear to habituate to acoustic pingers when exposed to them over more than one year
  • The use of acoustically reflective and stiffer nets does not appear to provide an effective option for preventing bycatch of Francisana
Project Partner(s)
Aquamarina, Argentina