Biological Conservation 55 (1991) 339-345 Life Strategies of some Long-Distance Migratory Catfish in Relation to Hydroelectric Dams in the Amazon Basin Ronaldo Borges Barthem Museu Paraense Emilio Goeldi, Departamento de Zoologia, CP 399, 66040 Belem (PA), Brazil Mauro C6sar Lambert de Brito Ribeiro Reserva Ecol6gica do IBGE, CP 04-0270, 70300 Brasilia (DF), Brazil & Miguel Petrere Jr UNESP, Departamento de Ecologia, CP 178, 13500 Rio Claro (SP), Brazil (Received 30 January 1990; revised version received 14 April 1990; accepted 30 May 1990) A BSTRA C T In this paper, we present evidence that the long-distance migrator), cat- .fish Brachyplatystoma filamentosum, B. flavicans, B. vaillantii, Goslinia platynema and Lithodoras dorsalis spawn in the headstreams of the Amazon river and its tributaries and that the estuary of the Amazon is the main nurser)' ground utilized by their alevins. The impact of hydroelectric dams on their populations are discussed in terms of interruption to fish migration routes up river and to larvae moving down river, provided that the hypothesis above holds. Ways of mitigating the impact are also considered. INTRODUCTION Tropical fish migrations are best known in South American rivers where a great variety of migratory patterns have been recognized, especially for 339 Biol. Conserv. 0006-3207/91/$03" 50 © 1991 Elsevier Science Publishers Ltd, England. Printed in Great Britain