Abstract Southern Hemisphere humpback whales (Megaptera novaeangliae) migrate from wintering grounds in tropical latitudes to feeding areas in the Antarctic Ocean. The movement patterns, migratory corridors, and feeding destinations of the whales wintering off eastern South America (IWC Breeding Stock ‘A’) have remained unknown for almost a century. It has been hypothesized that this population migrates to feeding grounds near the Antarctic Peninsula (ca. 65 o S, 60 o W) and/or South Georgia (54 o 20’S, 36 o 40’W), but direct evidence of support has never been presented. From 19 to 28 October 2003, 11 humpback whales (7 females and 4 males) were instrumented with satellite transmitters off Brazil (ca. 18 o 30’S, 39 o 30’W) to investigate their movements and migratory destinations. Two tag configurations were deployed using a fiberglass pole from a small skiff. Mean tracking time for the 11 whales was 40 days (range = 5-205 days) and mean distance traveled was 1726 km/whale (range = 60-7258 km). Departure dates from the Brazilian coast ranged from late October to late December indicating that some whales were still in the wintering grounds in the beginning of the austral summer. Arrival in the feeding grounds occurred from December to February. Migration lasted 40-60 days. Whales migrated south at an average heading of 170 o and traveled a relatively direct, linear path from wintering to feeding grounds. Two whales were tracked all the way to feeding grounds near South Georgia and the South Sandwich Islands (58 o S, 26 o W), where humpback whales were heavily exploited in the early 20th Century. Migratory routes and destinations match catch positions of humpback whales taken in the South Atlantic in the 1960’s. This study is the first to describe migration and summering grounds of humpback whales in the western South Atlantic Ocean. MATERIAL AND METHODS  Satellite transmitters were deployed on 11 whales near Conceição da Barra, Brazil (18 o 30’S, 39 o 30’W), in October 2003 (Table 1).  Tag deployment was done with a fiberglass pole as described by Heide- Jørgensen et al. (2003) (Fig. 3). A biopsy skin sample was simultaneously collected for determination of gender.  Two configurations of the SPOT3 satellite transmitter (Wildlife Computers, Redmond, WA, USA) were used: ‘Mini-can’ (n=7, Fig. 4) and ‘Implantable’ (n=4, Fig. 4). Duty cycling and programming varied by tag (Table 1).  Locations were obtained from Service Argos, Inc. Only higher accuracy locations (1, 2, 3) were used to calculate daily averages when examining short-range movements on the ‘wintering’ and ‘feeding grounds’. All location classes (B, A, 0, 1-3) were used to calculate daily average positions for long- range movements in the ‘migratory corridors’. Locations were deleted from the dataset if the observed speed between consecutive locations exceeded 15 km/h. Alexandre N Zerbini 1,5 , A Andriolo 2 , MP Heide-Jørgensen 3 , JL Pizzorno 4 , YG Maia 4 , GR VanBlaricom 1 , DP DeMaster 5 , PC Simões-Lopes 6 , S Moreira 4 and C Bethlem 4 1 Washington Cooperative Fish and Wildlife Research Unit, School of Aquatic and Fishery Sciences, University of Washington, Seattle, WA, USA; 2 Instituto de Ciências Biológicas, Universidade Federal de Juiz de Fora, MG, Brazil; 3 Greenland Institute of Natural Resources, Nuuk, Greenland; 4 Projeto Monitoramento de Baleias por Satélite, Rio de Janeiro, RJ, Brazil; 5 Alaska Fisheries Science Center, NMFS/NOAA Fisheries, Seattle, WA, USA; 6 LAMAQ/ECZ, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil INTRODUCTION  The migration routes and migratory destinations of humpback whales wintering off Brazil (Fig. 1) have remained unknown for almost one century.  Two hypotheses have been proposed: a coastal migration to the Falkland Islands and the Antarctic Peninsula (H-1 in Fig. 2, Slijper and Van Utretch 1959, Slijper 1962) and an offshore migration to the Scotia Sea near South Georgia (H-2 in Fig. 2, Slijper 1962, 1965; Mackintosh, 1965), but no direct evidence was provided to substantiate these hypotheses.  Studies involving Discovery marks, sighting surveys, photo-identification, and molecular genetics conducted on the wintering ground off Brazil and the presumed high-latitude feeding grounds near South Georgia and the Antarctic Peninsula have been unable to determine migratory connections of whales wintering off Brazil (e.g. IWC 1998, Moore et al. 1999, Rosenbaum et al. 2000, Stevick et al. 2004). Fig. 1 – Humpback whales wintering off Brazil IDENTIFICATION OF A SUMMERING GROUND OF HUMPBACK WHALES (MEGAPTERA NOVAEANGLIAE) IN THE SOUTHWEST ATLANTIC OCEAN OBJECTIVES  Investigate movements and determine migration routes and migratory destinations of humpback whales wintering off Brazil using satellite telemetry. Fig. 3 – Tag deployment Table 1 – Transmitters deployed in humpback whales off the coast of Brazil 1 – MC = mini-can, IMP = implantable; 2 - judged to be a male because it was an escort in a triad with a mother and a calf; 3 – eod – transmissions every second day; 4 – judged to be a female because it was the larger individual in a mother-calf pair Whale ID Sex Tag Type 1 Duty Cycling Daily Emissions Transmission Time Tagging Date (2003) Tag Longevity (days) No. of locations received No. of locations used Distance traveled (km) 20162 M 2 MC eod 3 300 6-21hs 19 Oct 13 10 8 850 20687 F MC none 500 0-23hs 27 Oct 23 319 229 933 21791 F MC none 500 0-23hs 28 Oct 14 166 86 743 21792 M MC none 500 0-23hs 27 Oct 5 52 24 60 21800 F MC none 500 0-23hs 28 Oct 31 287 99 965 21809 F MC none 500 0-23hs 27 Oct 14 51 6 598 21810 M IMP eod 300 6-21hs 18 Oct 76 84 52 4383 24640 F IMP eod 300 6-21hs 19 Oct 8 24 8 337 24642 F 4 IMP eod 300 6-21hs 27 Oct 205 624 324 7258 27259 F MC none 300 6-21hs 19 Oct 39 51 20 2315 27261 M IMP eod 300 6-21hs 18 Oct 8 5 2 516 Total 436 1673 858 18958 RESULTS  Tracks of three whales provided details of their migration route (Fig. 5). Whale #27259 was tracked for approximately 1/3 of the route, whereas whales #21810 and #24642 were tracked until they reached the feeding grounds.  The migration paths were consistent, irrespective of sex. Times of departure ranged across a period of two months (Fig. 5). The whales did not travel together, but their tracks intersected and were never more than 500 km apart.  Whales traveled a relatively direct, linear path and gradually moved away from the South American continent as they migrated to higher latitudes. They followed approximately the same route southward at an average geographic heading of 170 o .  Whales #27259 and #24642 traveled towards an area known as the ‘Brazil Banks’ (~ 31 o S, 35 o W), a former whaling ground off the eastern South American coast.  Two whales migrated to an area 270-400 km northeast of South Georgia (54 o 20’S, 36 o 40’W) ~ 3500 km southeast of the wintering ground (Fig. 5).  Individual #24642 (Fig. 5) spent 22 days NE of South Georgia and moved further southwest to the South Sandwich Archipelago (~ 58 o S, 26 o W). DISCUSSION AND CONCLUSIONS  This study provides the first direct evidence of migratory routes and destinations of humpback whales wintering off eastern South America.  Our results are consistent with the hypothesis of Slijper (1962, 1965) and Mackintosh (1965) (an offshore migration to the South Georgia and the South Sandwich Archipelago, H-2 in Fig. 2). Whales remained in offshore areas and did not move to former whaling grounds in coastal areas near South Georgia once they reached the feeding grounds.  Migration timing, routes, and destinations are further supported by recent catch records collected by Soviet fleets operating in the South Atlantic during the late 1960s and early 1970s (see Fig. 5, e.g. Mikhalev, 1998) and sighting data (Kasamatsu et al. 1996; Reilly et al. 2000). These indicate higher densities of humpback whales in offshore areas northeast of South Georgia.  Coastal migration towards the Falkland/Malvinas Islands and the Antarctic Peninsula was not observed. Contemporary data indicate that whales feeding near the Antarctic Peninsula migrate to the Pacific coast of South America (e.g. Olavarría et al. 2000, Stevick et al. 2004), refuting the hypothesis (H-1 in Fig. 2) proposed by Slijper and van Utretch (1959) and Slijper (1962).  The occurrence of humpback whales near the South Sandwich Archipelago is poorly known. Individual #24642 moved and remained in this region for at least 2.5 months. Krill abundance is relatively high near the South Sandwiches (Mackintosh, 1973; V. Decker, pers. comm.) suggesting this may be a suitable whale foraging habitat. Fig. 2 – Migratory hypotheses of whales wintering off eastern South America H-1 H-2 References  Heide-Jørgensen, MP et al. (2003) Arctic 56(1):21-31;  IWC (1998) Rep Int Whal Commn 48:170-182  Kasamatsu, F et al. (1996) Rep int Whal Comm 46:293- 304  Mackintosh, NA (1965) The Stocks of Whales. Fishing News (Books) Ltd, London  Mackintosh, NA (1973) Disc Rep 36:95-156  Mikhalev, Y (1998) Rep Int Whal Comm 48:170-182  Moore, MJ et al. (1999) Mar MammSci 15(4):1287-1302  Olavarría C et al. (2000) Paper SC/52/IA15, IWC SC, June 2000, Australia. 12pp  Reilly, S et al. (2000) Paper SC/52/E21, IWC SC, June 2000, Australia. 19pp  Rosenbaum, HC et al. (2000) Paper SC/52/IA11, IWC SC, June 2000, Australia. 12pp.  Slijper, EJ (1962) Whales. Hutchinson, London  Slijper, EJ (1965) Mededelingen 19:29-61  Slijper, EJ, van Utrecht, WL (1959) The Norwegian Whaling Gazette 3:101-17  Stevick, PT et al. (2004) J Cetacean Res Manage 6(2):109-114 Fig. 5 – Whale #24642, tagged off Brazil with an implantable tag (note tag location and size - red circle). Fig. 5 – Migratory routes and destinations of humpback whales marked with satellite transmitters in the wintering grounds off eastern South America. Acknowledgements  Funding and Logistical Support: Exploration and Production Division of Shell Brasil Ltda (Mr. F. Caravello, Ms. P. Garcia and Mr. J. van den Dries); Conselho Nacional para o Desenvolvimento Científico e Tecnológico (CNpq) Biodinâmica Engenharia & Meio Ambiente Ltda; The National Marine Mammal Laboratory/NMFS/NOAA; The Washington Cooperative Fish and Wildlife Research Unit/School of Aquatic and Fishery Sciences/UW.  Tag deployment: M.V. and A.V. Jensen  DNA Extraction: Dr. C. Miyaki and T. Matsumoto, Instituto de Biociências, Universidade de São Paulo, Brazil.  Field Assistance: L.C.P. de S. Alves, M.A.B. Crespo, D. Danilewicz, M. de O. Dutra, M.C. de Lyra, E. Marone, J.V.A. Rocha and S.M. Simão.  Catch data and literature: Drs. P. Best, R Brownell Jr, and P. Clapham  Permit numbers: CNPq (grant # CMC 026/02-028/03), the Brazilian Environmental Agency (IBAMA, permit #009/02/CMA/IBAMA, process # 02001.000085/02-27). 5 cm 5 cm Fig. 4 – Mini can (top) and implantable (bottom) satellite transmitters The recommendations and general content presented in this poster do not necessarily represent the views or official position of the Department of Commerce, the National Oceanic and Atmospheric Administration, or the National Marine Fisheries Service SEE ALSO: Precautionary Regression-based Determination of Protective Boundaries for Migratory Corridors of Large Whales by G.R. VanBlaricom, A.N. Zerbini, D.P. DeMaster, A. Andriolo, M.P. Heide-Jørgensen, B.M. Blaud and M. Logsdon. Poster on Session A, Bay 21, Poster 6. Presentation time: Wed 14 Dec 8:30-9:30am