The high bycatch rates in fishing nets make the franciscana dolphin (Pontoporia blainvillei) the most endangered small cetacean in the Western South Atlantic Ocean. Among possible solutions for bycatch is the use of acoustic alarms, or “pingers”, which are easy to implement, and can reduce mortality in the short-term. Nonetheless, the feasibility of its implementation and their efficiency in particular regions must be evaluated, including the analysis of side effects (FAO, 2019). There is evidence that high-frequency “seal-safe” pingers are effective in warding off franciscanas (Bordino, 2018; Paitach et al., 2022), but this needs to be validated in a real fishing situation, with several pingers arranged along a gillnet and operational and socioeconomic applicability of this approach being evaluated. Understanding the acoustic behavior of franciscanas in the vicinity of the nets, and how their behavior is affected by the pingers, is also needed in order to implement this solution.

At the same time, it is essential to involve fishing communities through educational and environmental awareness actions. The monitoring of abundance is an essential factor to assess the conservation status and the effectiveness of public policies that aim to contribute to the reduction of mortality. Considering the specific characteristics of the sounds produced by the franciscanas, the MAP is an alternative, including for monitoring the distribution of the species on a large scale (Paitach et al., 2022). Therefore, it is essential to know the basic parameters to obtain population estimates of the franciscana by acoustic methods, such as the individual emission rate, whose information is not available. In addition to contributing information on population parameters, towing acoustics allows the collection of data on the distribution of franciscana populations, which represents an important benefit for environmental impact assessment in the coastal zone.

*This grant was made possible in partnership with the Brazil Foundation, who served as the grant maker.