Bottlenose Dolphins in Laguna Requesting a Throw Net

In collaboration with colleagues Arthur Schiefler and Prof. Dr. Geraldo Milioli, I have studied what Karen Pryor refers to as "a dolphin-human fishing cooperative in Brazil (Marine Mammal Science 6:77--82). We were especially interested in this question: "Do the dolphins understand that they are giving a signal to the fishermen to cast the net, or have they acquired this unique signal through blind, mindless, years-long, trial and error learning?" We paid therefore particular attention to the fairly standardized and stereotypic signal given by these bottlenose dolphins. We do not know yet whether the dolphins understand their signaling action, but we plan to publish a detailed description and analysis of the signal itself. Until we get around to this laborious job, we decided to place some of our best signaling clips, of different dolphins, on the web. We would welcome any comments and interpretations of what is seen here (aa1674@wayne.edu). Here, anyway, is one sequence of dolphins Arreia Braço first, and then Ligerinho, taking place on November 2, 2006.

We may also note in passing that this natural wonder is under severe threat, leading to at least two applications 1. If you find yourself in the Laguna area, it's well worth a visit. It's one of the most beautiful towns in Brazil, with great surfing and wonderful people--all these besides the signaling dolphins. 2. Maybe, if just enough people realize the grave threat (from pollution, overfishing, overpopulation, motor boats . . . ) to the remnants of this natural wonder, the dolphins, and the way of life of the traditional fishermen and hobbyists, can still be saved. It's almost Earth Day, 2008, when we're posting this, so maybe humanity, Brazil, the state of Santa Catarina, the cities of Tubarão and Laguna, will still come to their senses and save this fabulous, incredibly beautiful and touching, dolphins and their odd way of sustaining themselves in a hostile world.

Supporting material for Dr. Nissani's presentation at the 2007 International Ethological Conference. To read his lecture, please go to: http://www.is.wayne.edu/mnissani/Elep...

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