SC/63/SH19 COMPARISON OF THE HUMPBACK WHALE CATALOGUES BETWEEN ECUADOR, PERU AND AMERICAN SAMOA. EVIDENCE OF THE ENLARGEMENT OF THE BREEDING STOCK G TO PERU. Castro, C. 1 ; Alcorta, B 2 .; Allen, J. 3 ; Cáceres, C. 4 ; Forestell, P. 1,5 ; Kaufman, G. 1,5 ; Mattila, D. 10 ; Pacheco, A.S. 2,7 ; Robbins, J. 6 ; Santillán, L. 4, 8; Scheidat, M. 1,9 ; Silva, S. 2 and A. Tagarino 11 . 1 Pacific Whale Foundation, Barrio Luis Gencón, Puerto López, Ecuador 2 Pacifico Adventures-Manejo Integral del Ambiente Marino. Av. Rivera del Mar s/n Organos, Piura, Perú. 3 College of the Atlantic, 105 Eden Street, Bar Harbor, ME 04609. 4 ONG Prodelphinus, Lima, Perú 5 Pacific Whale Foundation, Maui, USA 6 Provincetown Center for Coastal Studies, 5 Holway Avenue, Provincetown, Massachusetts 02657, USA 7 Instituto de Investigaciones Oceanologicas, Universidad de Antofagasta, P.O. Box 170. Antofagasta, Chile 8 Centro Peruano de Estudios Cetológicos (CEPEC) Pucusana, Perú 9 Institute for Marine Resources & Ecosystem Studies. The Netherlands. 10 Hawaiian Islands Humpback Whale National Marine Sanctuary, Kihei, HI, USA 11 Department of Marine and Wildlife Resources, Pago Pago, American Samoa Contact e-mail: cristinacastro@pacificwhale.org ABSTRACT We compared the catalogues of photo-identified humpback whales from four research groups working in Southern Hemisphere breeding areas collected between 1996 and 2010. The entire dataset included individuals: 1470 from Ecuador 96 from Peru and 168 from America Samoa (Breeding Stock E-3). Two matches were found between Ecuador and Peru catalogs, all of them were inter-year re-sightings. Our data confirms that the breeding area of the Stock G extends approximately 700 km to south of Ecuador. Our study suggests and adds further evidence the northern Peru coastal area may be considered as the southern limit of the breeding area for BS-G. In addition, our study highlights the importance of continuing the exchange of catalogs with other adjacent and on/adjacent, which would have implications for management and conservation. KEY WORDS: Megaptera novaengliae, breeding grounds, photo-ID, movements, stock G, America Samoa, Peru, Ecuador. INTRODUCTION Southern Hemisphere humpback whales (Megaptera novaeangliae) migrate from their feeding grounds in Antarctic waters to the tropics (Matthews, 1937). The breeding stock G humpbacks migrate from the Area I (west of the Antarctic Peninsula) (Stone et al. 1990, Stevick et al. 2004) and Magellan Strait in Chile (Acevedo et al. 2007; Capella et al. 2008) during the austral summer until off Ecuador and Colombia during the austral winter (Florez-Gonzalez et al. 1998; Scheidat et al. 2000, Felix and Haase 2001). In recent years, southeast Pacific humpback whales have been found further north, off Panama, Costa Rica (Acevedo and Smultea 1995; Flórez-González et al. 1998, Rassmusen et al. 2007) and north of Peru (Castro et al. 2008; Pacheco et al. 2009; 2011). Photographic identification of individual humpback whales has established and confirmed migratory movements all over the world (Kaufman et al. 1990, Stone et al. 1990, Darling & Cerchio 1993, Stevick et al. 1998, 2004). An connection has been established between whales breeding in tropical areas on the west coast of Central and South America with those using feeding sites located in southern Chile (Acevedo et al., 2007), western Antarctic Peninsula (Stone, et al., 1990, Stevick et al., 2004, Rasmussen et al. 2007; Castro et al., 2008). Individual humpback whale movements between nearby areas in Panama, Colombia, Ecuador and Peru suggest the species have a continuous distribution in such coastal areas (Flórez-González et al., 1998; Castro et al. 2008; Felix et al. 2009). Some additional humpback exchanges between Ecuador and Peru were presented by Castro et al. (2008), with recaptures discovered due to minimal effort in Peru until 2007. Since 2008, two research 1