Brito et al. (2010) IWC - SC/62/SM8 1 Small cetaceans off São Tomé (São Tomé and Príncipe, Gulf of Guinea, West Africa): Species, sightings and abundance, local human activities and conservation CRISTINA BRITO 1, 2 , CRISTINA PICANÇO 2 & INÊS CARVALHO 3, 4, 5 (1) CHAM, Centro de História de Além-Mar, Faculdade de Ciências Sociais e Humanas, Universidade Nova de Lisboa, Avenida de Berna, 26 C, 1069-061 Lisboa, Portugal (2) Escola de Mar, Edifício ICAT, Campus da FCUL, Campo Grande, 1749-016 Lisboa, Portugal, +351966552928, info@escolademar.pt (3) Faculdade de Ciências do Mar e Ambiente – Universidade do Algarve, Campus Gambelas, 8000-139 Faro, Portugal. (4) Sackler Institute for Comparative Genomics - American Museum of Natural History 79 th Street and Central Park West, New York, NY, 10024, USA. (5) Ocean Giants Program, Wildlife Conservation Society, 2300 Southern BLVD., Bronx, NY 10460- 1099, USA. ABSTRACT Humans and cetaceans are both part of complex marine ecosystems and large ocean mega fauna, such as marine mammals, are often used to direct conservation efforts. São Tomé and Príncipe is an African equatorial archipelago situated in the Gulf of Guinea, which seems to be an important marine area for cetaceans. However, as in many parts of the world, the status of marine species or populations has not been assessed mainly due to lack of information. Four species of small cetaceans were identified, bottlenose dolphins (Tursiops truncatus) with the highest sighting rate and pantropical spotted dolphins (Stenella attenuata) the highest abundance rate. These two species occurred during almost all sampling months while killer whales (Orcinus orca) seem to be present in just a part of the year. Most observed behaviours were traveling (32%) and feeding (57%) and most of the groups were formed by adults, juveniles and calves (81%). In this study we identified five human activities with very different possible impacts on cetaceans - (1) historical whaling; (2) fishing and by-catches; (3) tourism; (4) debris and pollution; (5) oil exploration - and all this needs to be put into context to understand the dynamics of the ecosystems where these natural populations live. Also, since the ending of 20 th century whaling, there is no legal background to regulate specific activities related specifically with marine environment and cetaceans. Several measures regarding the conservation of natural populations of cetaceans are suggested but most importantly, in São Tomé and Príncipe, is to allow a change to a more conservation-oriented perspective. Scientific research, interactive and continuous environmental education plans and well established whale watching programs need to be developed. Moreover, scientists, policymakers and local resources users need to be involved as knowledgeable stakeholders. KEYWORDS Dolphins, occurrence, SPUE, APUE, fisheries, eco-tourism, legislation, São Tomé and Príncipe, Gulf of Guinea, West Africa.