Danilewicz et al.: Reproductive biology of male Pontopona blainvillei from Rio Grande do Sul, southern Brazil 



591 



and Rio Grande. Many people collaborated in the collec- 

 tion and necropsy of the dolphins, and the authors wish 

 to thank Paulo Ott, Ignacio Moreno, Marcio Martins, 

 Glauco Caon, Larissa Oliveira, Manuela Bassoi, Alexan- 

 dre Zerbini, Luciana Moller, Luciano Dalla Rosa, Lilia 

 Fidelix, and numerous volunteers for helping in this 

 task. Gonad histology was partially done in Laboratorio 

 de Histologia e Embriologia Comparada of Universi- 

 dade Federal do Rio Grande do Sul and we thank Sonia 

 Garcia and Nivea Lothhammer for their instructions 

 and encouragement on this subject. Paulo Ott, Enrique 

 Crespo and Silvana Dans participated in the age deter- 

 mination procedures. Part of the age determination was 

 also done in the Rio Grande and the first author thanks 

 Cristina Pinedo and Fernando Rosas for their instruc- 

 tion. The authors also thanks Norma Luiza Wiirdig, 

 Iraja Damiani Pinto (CECLIMAR-UFRGS), and Lauro 

 Barcellos (Director of the Museu Oceanografico) for their 

 constant logistical support and for encouraging marine 

 mammal studies in southern Brazil. Marcio Martins, 

 Ignacio Moreno, Luiz Malabarba, and Monica Muelbert 

 reviewed an early draft of this paper. We wish to thank 

 Renata Ramos and three anonymous reviewers for their 

 suggestions regarding the manuscript. Financial support 

 was given by Cetacean Society International, Fundacao 

 O Boticario de Protecao a Natureza, The MacCarthur 

 Foundation, World Wildlife Fund, CNPq, UNEP, Yaqu 

 Pacha Organization, and Whale and Dolphin Conser- 

 vation Society. This paper is part of the first author's 

 M.S. thesis, and The Coordenagao de Aperfeicoamento 

 de Pessoal de Nivel Superior (CAPES) has granted 

 him a graduate fellowship. The Conselho Nacional de 

 Desenvolvimento Cientifico e Tecnologico of the Brazilian 

 Government (CNPq) has granted graduate fellowships 

 to E.R. Secchi (Grant no. 200889/98-2). 



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