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Licensed Unlicensed Requires Authentication Published by De Gruyter March 9, 2016

Estimated population size of two South American sea lion male haulouts from the northern coast of Argentina

Gisela Giardino, Julián Bastida, M. Agustina Mandiola, Ricardo Bastida and Diego Rodríguez
From the journal Mammalia


Knowledge of the real size of any wild population is an essential tool to take management and conservation measures and even more so when the population studied may have potential conflicts with humans. Because of this, the objective of this study was to estimate the population size of two South American sea lion male haul-outs using mark-resighting techniques. The results showed that on average, the estimated total number of animals tripled the number of animals recorded by direct counting. These findings demonstrate that it is necessary to continue researching population estimate methods to apply when taking conservation measures in the future.

Corresponding author: Gisela Giardino, Instituto de Investigaciones Marinas y Costeras (IIMyC), Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata–CONICET, Casilla de Correos 1260 (Correo Central), (7600) Mar del Plata, Argentina, e-mail:


We thank Prefectura Naval Argentina (Puerto Quequén), Consorcio de Gestión de Puerto Quequén, and the lifeguards of “Playa los Patos” for their help in the field. We also thank Professor Laura N. Kloepper and Victoria Lichtschein for reviewing the English version of this article and for her very useful comments and Dr. P. Denuncio for making the map. G. Giardino and M.A. Mandiola were granted Doctoral fellowships by Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) and Society for Marine Mammalogy Grants in Aid of Research (2008, 2012). This study was part of G. Giardino’s PhD program at Universidad Nacional de Mar del Plata.


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Received: 2015-9-10
Accepted: 2016-1-14
Published Online: 2016-3-9
Published in Print: 2017-3-1

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