The franciscana (Pontoporia blainvillei) is the most threatened coastal dolphin in Brazil and is listed as critically endangered on the Brazil Red Book of Threatened Species of Fauna (ICMBio). The main threat to the species is the unintentional, accidental capture in fishing nets (i.e. bycatch), and mitigating this situation is one of the main challenges for the conservation of the species.

To help mitigate this problem, the Toninhas do Brasil project will test the use of acoustic alarms in nets, in different artisanal fishing realities, in an unprecedented way. Bringing together researchers and institutions from the states of Santa Catarina, Paraná, and São Paulo, the project’s research and conservation efforts are focused on carrying out a pilot experiment with pingers. Pinger A pinger is a small, battery-powered device that, when attached to fishing nets, emits an ultrasonic signal that alerts dolphins of the threatening nets, thus preventing bycatch. These devices have already been tested by the project in controlled experiments and, according to research coordinator Renan Paitach, presented satisfactory results, with great potential to assist in the conservation of franciscanas. “When the pinger is turned on, the franciscanas stay at a distance of at least 100m, and when it is turned off, they return to the area only a few minutes later. Now, we have to understand how the pinger will work in real fishing contexts, considering operational and socioeconomic aspects”.

At this stage, the challenge is to monitor the experiment in different artisanal fishing realities along the coast. On an ongoing basis, fishermen from five communities will use pingers in their nets, which will be monitored over the next two years. For biologist Marta Cremer, general coordinator of the project, the experiment represents a major advance in favor of the conservation of the species. “Since its beginning, Toninhas do Brasil has focused its efforts on finding alternatives for conservation, always considering the needs of local communities. When capture is accidental, thinking about alternatives that reduce these interactions are beneficial for everyone, from animals to fishermen.”

However, the researcher considers that effective measures for the conservation of the franciscanas are not simple and must involve different strategies, such as the use of technologies to reduce bycatch, fisheries regulations and other public policy initiatives. The Project’s scope of action also includes a diagnosis of the fish production chain, dialogue meetings with fishermen and other stakeholders, a course for public school educators and a strategic communication plan. The Project is partnered with Petrobras, and is supported by Dolphin Quest through the Conservation of Threatened or Endangered Small Cetaceans Fund. In partnership with Petrobras, through the Petrobras Socioenvironmental Program, the project is expected to reach at least 14 communities through all of the aforementioned activities, across the three states, thus effectively contributing to the construction of a cooperative proposal for franciscana bycatch mitigation and for a more sustainable fishing.

Franciscana or Toninha, the invisible dolphin

The franciscana, scientifically known as Pontoporia blainvillei, is a small dolphin endemic to the Southwestern Atlantic Ocean, occurring only in the waters of Brazil, Uruguay and Argentina. With coastal habits, franciscanas are found at depths of up to 50 meters, forming small groups. This characteristic makes the species vulnerable to intense pressure exerted by human activities, especially fishing, which is more intense near the coast, with gillnet bycatch being the main risk to the conservation of the species. The franciscana is considered a Vulnerable species, according to the IUCN Red List of Threatened Species (IUCN, 2017). However, in Brazil, the species went from “Vulnerable” to “Critically Endangered” in just ten years. However, in Brazil, the species went from “vulnerable” to “critically endangered of extinction” in just ten years.

Between August/2015 and October/2020, 2,696 dead franciscanas were found between the coast of the states of Santa Catarina and São Paulo. The total franciscana population estimated for this portion of the coast is less than 7,000 individuals. The high risk of its disappearance, combined with the species’ more discreet behavior, including an almost total lack of jumps to the surface, has led many researchers and supporters to call the franciscana the “invisible dolphin”. This nickname, in addition to referring to the characteristics of the species, sheds light on the discussion of how poorly known the franciscana is and the risk of its disappearance before scientists can even get to know more about them.

Follow Projeto Toninhas do Brasil on social media @toninhasdobrasil

Contact for interview:

Marta J. Cremer (General Coordinator – Toninhas Project)

Telephone: (47) 3471-3816


Naira Albuquerque (Assessora de Comunicação – Projeto Toninhas)

Telefone: (54) 99931-8004 E-mail:

Pesquisadores de três estados se unem em um projeto inédito com alarmes acústicos em redes de pesca para redução de captura acidental de toninhas