Proposal for creation of a "zoning with regulation of use in the Cananéia estuarine-lagoon complex" aiming the conservation of the estuarine dolphin, Sotalia guianensis (van Bénéden) (Cetacea, Delphinidae)

Abstract

The increase in human activities in the coastal region has affected the stability of certain cetacean populations. In the Southeastern Brazilian coast, the populations of estuarine dolphins, Sotalia guianensis (van Bénéden, 1864) suffer strong pressure as a result of long exposure to pollution, reduction of habitats, by-catch and tourism. Since 1981, the Instituto de Pesquisas Cananéia (IPeC) studies the biology and ecology of the estuarine dolphin in the Cananéia-Paranaguá estuarine-lagoon complex. Since then, we have obtained information on group structure, population density, reproduction, foraging, behavior, acoustics, video identification and interactions with other species, including the local human community. These data indicates that the traffic of fishing boats does not interfere in the activities of the estuarine dolphin. However, small boats with outboard motor may interfere physically; through collisions with dolphins or stressing them, and also may interfere in their acoustic behavior. Therefore, with the intention of acting effectively in the conservation of the estuarine dolphin, without excluding human activities we formulated a proposal for creation of an area of "zoning with regulation of use" which consists in outlining sectors of greater density of dolphins in the Cananéia estuarine-lagoon complex.