[1] Univ Republ, Ctr Univ Reg Este, Dept Ecol & Evolut, Maldonado 20000, Uruguay
[2] Univ Republica, Fac Ciencias, Secc Etol, Proyecto Pinnipedos, Montevideo 11400, Uruguay
[3] Univ Barcelona, Fac Biol, IRBIO, Barcelona 08028, Spain
[4] Univ Barcelona, Fac Biol, Dept Anim Biol, Barcelona 08028, Spain
[5] Univ Republica, Fac Ciencias, Dept Ecol & Evoluc, Montevideo 11400, Uruguay
[6] Consejo Nacl Invest Cient & Tecn, Ctr Nacl Patagon CENPAT, Lab Marine Mammals, RA-9120 Puerto Madryn, Chubut, Argentina
[7] Natl Univ Patagonia, RA-9120 Puerto Madryn, Chubut, Argentina
[8] Study Grp Aquat Mammals Rio Grande Sul GEMARS, BR-95625000 Imbe, RS, Brazil
[9] Univ Fed Rio Grande do Sul, Dept Zool IB, Lab Sistemat & Ecol Aves & Mamiferos Marinhos Lab, BR-91509900 Porto Alegre, RS, Brazil