Southern Hemisphere humpback whales Megaptera novaeangliae migrate from wintering grounds in tropical latitudes to feeding areas in the Antarctic Ocean. It has been hypothesized that the population wintering off eastern South America migrates to feeding grounds near the Antarctic Peninsula (ca. 65°S, 60°W) and/or South Georgia (54°20' S, 36°40' W), but direct evidence to support this has never been presented. Between 19 and 28 October 2003, 11 humpback whales (7 females and 4 males) were instrumented with satellite transmitters off Brazil (ca. 18°30' S, 39°30' W) to investigate their movements and migratory destinations. Mean tracking time for the whales was 39.6 d (range = 5 to 205 d) and mean distance travelled was 1673 km per whale (range = 60 to 7258 km). Movements on the wintering ground showed marked individual variation. Departure dates from the Brazilian coast ranged from late October to late December. Whales migrated south through oceanic waters at an average heading of 170°and travelled a relatively direct, linear path from wintering to feeding grounds. Two whales were tracked to feeding grounds in offshore areas near South Georgia and in the South Sandwich Islands (58°S, 26°W) after a 40 to 60 d long migration. Historical catches and current sighting information support these migratory routes and destinations. This study is the first to describe the movements of humpback whales in the western South Atlantic Ocean.

The potential impact of increasing vessel traffic and coastal development has led to concerns regarding the future of the Brazilian humpback whale Megaptera novaeangliae population. Our objective was to monitor humpback whale abundance in the Brazilian coastal breeding grounds in order to provide information to support future conservation strategies for this species. To this end, a 4 yr series (2002 to 2005) of aerial surveys was implemented. Abundance was estimated using standard line-transect methods. Data were analyzed using the software DISTANCE 5.0. Perpendicular sighting data were modeled using (1) the uniform function with cosine and simple polynomial adjustments, (2) the half-normal function with cosine, and (3) the hazard-rate function with cosine and a simple polynomial series expansion. The model that best fitted the data was selected according to Akaike's Information Criterion (AIC). We estimated the population off the Brazilian coast to be 6404 (CV = 0.11) ind. in 2005. Alternative scenarios are presented to permit the discussion of results obtained from different g (0) corrections (where g (0) is the probability of detecting an animal at distance 0). We confirmed what previous studies have shown, i.e. that the studied population is increasing, and it is expected that new areas will be occupied and conflicts of interests will arise. The results of this study support the Brazilian government's stance against whaling and should be used in national and international debate to help solve conflicts of interest and to find non-lethal solutions.

Humpback whale seasonal migrations, spanning greater than 6500 km of open ocean, demonstrate remarkable navigational precision despite following spatially and temporally distinct migration routes. Satellite-monitored radio tag-derived humpback whale migration tracks in both the South Atlantic and South Pacific include constant course segments of greater than 200 km, each spanning several days of continuous movement. The whales studied here maintain these directed movements, often with better than 18 8 8 8 8 precision, despite the effects of variable seasurface currents. Such remarkable directional precision is difficult to explain by established models of directional orientation, suggesting that alternative compass mechanisms should be explored.

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Around 176500 whales were killed in the sub-Antarctic waters off South Georgia (South Atlantic) between 1904 and 1965. In recent decades, whales have once again become summer visitors, with the southern right whale (SRW) the most commonly reported species until 2011. Here, we assess the distribution, temporal pattern, health status and likely prey of SRWs in these waters, combining observations from a summertime vessel-based expedition to South Georgia, stable isotope data collected from SRWs and putative prey and sightings reports collated by the South Georgia Museum. The expedition used directional acoustics and visual surveys to localise whales and collected skin biopsies and photo-IDs. During 76 h of visual observation effort over 19 expedition days, SRWs were encountered 15 times (~31 individuals). Photo-IDs, combined with publicly contributed images from commercial vessels, were reconciled and quality-controlled to form a catalogue of 6 fully (i.e. both sides) identified SRWs and 26 SRWs identified by either left or right sides. No photo-ID matches were found with lower-latitude calving grounds, but 3 whales had gull lesions supporting a direct link with Península Valdés, Argentina. The isotopic position of SRWs in the South Georgia food web suggests feeding on a combination of copepod and krill species. Opportunistic reports of SRW sightings and associated group sizes remain steady over time, while humpback whales provide a strong contrast, with increased sighting rates and group sizes seen since 2013. These data suggest a plateau in SRWs and an increasing humpback whale presence in South Georgia waters following the cessation of whaling.

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The population of humpback whales (Megaptera novaeangliae) wintering off the eastern coast of South America is referred to by the International Whaling Commission as ‘Breeding Stock A’ (BSA). This population was heavily exploited in 20th century modern commercial whaling operations. After more than 30 years of protection, its present status remains unknown. A deterministic sex and age-aggregated population dynamics model was used to estimate the pre-exploitation population size (K), the maximum net recruitment rate (rmax), the maximum depletion level (Nmin/K), and other quantities of interest of BSA. Input data included modern whaling catch series, absolute estimates of abundance, observed growth rates and indices of relative abundance. A Bayesian statistical method was used to calculate probability distributions for the model parameters. Prior distributions were set on rmax – an uninformative (Uniform [0, 0.106]) and an informative (Normal [0.067, 0.042]) – and on the population size in 2005 – N2005 (Uniform [500, 22,000]). A total of 10,000 samples were used to compute the joint posterior distribution of the model parameters using the Sampling-Importance-Resampling algorithm. Sensitivity of model outputs to the priors on rmax, a genetic constraint, data inclusion and catch allocation scenarios was investigated. Medians of the posterior probability distributions of quantities of interest for the base case scenario were: rmax = 0.069 (95% probability intervals [PI] = 0.013–0.104), K = 24,558 (95% PI = 22,791–31,118), Nmin/K = 2% (PI = 0.31%–12.5%), N2006/ K = 27.4% (PI = 18.3%–39.5%), N2020/K = 61.8% (PI = 23.8%–88.6%), and N2040/K = 97.3% (PI = 31.6%–99.9%). Despite apparent recovery in the past three decades, the western South Atlantic humpback whale population is still low relative to its pre-exploitation size and requires continued conservation efforts.

The Amazon's reputation and ability to draw tourists is strongly associated with the natural environment and with tourist's ability to sight and interact with iconic animals. In Brazil, four cases of aggregations of wild boto (Amazon River dolphin; Inia geoffrensis), becoming conditioned to human contact through food provisioning are occurring in Amazonas State, Central Amazon, where tourists can feed, touch and swim with the botos. The feeding of wild dolphins imposes significant risks, both for the dolphins and for the tourists, and these dangers are evident at Novo Airão City, which is the longest established of the four mentioned cases. There are few rules imposed, inadequate infrastructure and no specialized employee training or surveillance. Competitive, aggressive interactions between dolphins, pushing, ramming and biting are common and a number of dangerous interactions between the dolphins and tourists have been observed. It is evident that the establishment of this tourist-dolphin interaction is facilitated by the deliberate feeding of the dolphins and that this activity has become financially lucrative for local people. Despite bringing benefits to the region, the growth of this 'botos feeding tourism' activity in the Amazon is currently poorly managed and there is a high risk of injury or fatality if interactions continue to develop without improved and careful management. Additional key words: swim-with-dolphins, Amazon, wildlife management. Resumo (O crescimento do "turismo de alimentação de botos", uma nova indústria de turismo baseada no boto da Amazônia, Inia geoffrensis, no Estado do Amazonas, Brasil)-Na Amazônia, a habilidade e tradição de atrair turistas estão fortemente associadas ao ambiente natural e à oferta turística de observação e interação com animais icônicos. No Brasil, quatro casos de agregações de botos da Amazônia (também chamado de boto-vermelho ou boto-cor-de-rosa; Inia geoffrensis) condicionados ao contato humano através da alimentação deliberada vêm ocorrendo no Estado do Amazonas, na Amazônia Central, onde os turistas podem alimentar, tocar e nadar com os botos. A alimentação de golfinhos selvagens implica significantes riscos, tanto para os animais como para os turistas, e esses riscos são evidentes na cidade de Novo Airão, que é o mais antigo dos quatro casos mencionados. Existe pouca regulamentação, infraestrutura inadequada e ausência de profissionais especializados para monitorar as atividades. Interações competitivas e agressivas, empurrões, investidas e mordidas são comuns entre os botos, assim como interações de risco entre os turistas e os animais. É evidente que o estabelecimento dessa interação homem-golfinho é facilitado pela alimentação deliberada e que a atividade se tornou financeiramente lucrativa para a população local. É também claro que essa é uma atividade repleta de riscos, tanto para os botos como para os turistas. Apesar de trazer benefícios para a região, o crescimento desse 'turismo de alimentação de botos' na Amazônia é atualmente mal manejado e exis...