Researchers study the appearance of 500 dolphins on the beaches of Rio

Researchers from the State University of Rio de Janeiro (Uerj) are going to investigate the appearance of around 500 dolphins of the Guiana dolphin species (Sotalia guianensis), including adults, juveniles and calves, in Guanabara Bay and on beaches in the city of Rio de Janeiro. January. They were seen on Wednesday (4) and the image enchanted locals and tourists alike.

This is the first time such a large group has been found on Rio’s beaches in the last 30 years. The objective of the investigation is to know the origin of these animals and if any of them joined the population of Guanabara Bay.

According to José Lailson Brito, oceanographer and one of the coordinators of the Laboratory of Aquatic Mammals and Bioindicators at Uerj (Maqua), the animals are probably from Ilha Grande Bay and made the trip to the city of Rio de Janeiro in search of food.

“We believe they are dolphins from Ilha Grande Bay, because only in Ilha Grande Bay do Guiana dolphins form extremely large groups like the ones we saw here. The other thing that drew attention is that the group had many calves, juveniles and calves, which is also very characteristic of these large groups in Ilha Grande Bay”, explained the oceanographer.

José Lailson said that the research will be carried out based on photo catalogs of river dolphins in the state of Rio de Janeiro. The photographs will be compared with the images recorded on Wednesday. “From there, we hope to start explaining who these animals are that came here and gather more information to know what they were really doing here”.

The director of the Mar Urbano Institute, marine biologist Ricardo Gomes, explains that with the improvement of water conditions [na Baía de Guanabara] the phenomenon may start to be seen more often. “Everything indicates that with the treatment, the sanitation being carried out, the sewage treatment being carried out by Águas do Rio, everything indicates that the environmental condition here on our beaches will improve, and I hope that a sighting like that is a more commonplace thing in the world. future”.

Another interesting characteristic of the passage of the dolphins was the appearance of females, which can help to repopulate the area of ​​Guanabara Bay, with a current population of less than 30. In the 80’s, the place already had around 400 dolphins.

Translated to english by RJ983

From Brazil, by EBC News