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Study area located at Pipa beach, municipality of Tibau do Sul, Rio Grande do Norte state, Brazil. (Map elaboration by Ana Alencar.) 

Study area located at Pipa beach, municipality of Tibau do Sul, Rio Grande do Norte state, Brazil. (Map elaboration by Ana Alencar.) 

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Article
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This study investigated the emission of subaquatic noise from recreational tourism motorboats, schooners and a sea-bottom mounted water pump. Analyses demonstrated alterations in several whistle (IF: t = 2.42, P = 0.015; FF: t = −2.22, P = 0.025) and calls patterns (MIF: t = −3.13, P = 0.001; MAF: t = −3.49, P = 0.0005; FD: t = −2.21, P = 0.027; D:...

Context in source publication

Context 1
... study area consists of two inlets, Madeiro and Curral, belonging to the district of Pipa in the municipality of Tibau do Sul. It is located in the southernmost part of Rio Grande do Norte state (06813 ′ 23.9 ′′ S 35804 ′ 14.8 ′′ W), 90 km from Natal, the state capital, North-eastern Brazil (Figure 1). ...

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Citations

... Cetaceans may also occasionally present speci c The effects of anthropogenic noise on Guiana dolphin (Sotalia guianensis, van Bénéden, 1864), a species that inhabits estuaries and bays between southern Brazil and Honduras, are still poorly understood. A number of responses have been documented, however, including an increase in whistle rates (Bittencourt et al. 2017), a signi cant increase in the initial and nal frequency of the whistles (Martins et al. 2018), and a reduction in whistle duration (Bittencourt et al. 2017). The Guiana dolphin is classi ed as 'Vulnerable' in Brazilian waters (ICMBio 2011), and understanding the global conservation status of the species was considered to be a priority by the International Whaling Commission (IWC) in 2018. ...
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... The bottlenose dolphins significantly produced more whistles at the onset of approaching compared to during and after vessel approaches [38]. For Sotalia guianensis, shipping noise from motorboats caused a significant increase in the number of whistles and a decrease in clicks [39]. Humpback dolphins significantly increased the whistle rate immediately when a boat passed through the area less than 1·5 km from the groups. ...
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... Boats may be potential agents of disturbance for marine mammals (New et al., 2015), especially cetaceans of the order Odontoceti, because they depend on emissions of sound to communicate with other members of the species and to capture prey (Monteiro-Filho and Monteiro, 2001). Boat noise in coastal areas is a major source of disturbance for cetaceans, especially for resident populations (Leão-Martins et al., 2018), and the interactions between boats and cetaceans appear to be biologically significant for these animals (Lusseau, 2003;New et al., 2015). Whale-watching boat operators commonly exhibit inappropriate conduct in cetacean areas, including directly and insistently approaching dolphins and dividing dolphin groups with their boats. ...
... During that year, a single boat carried tourists to observe the Guiana dolphins. In 2002, there were already three boats doing the trips, and in 2009, there were 10 boats (Leão-Martins et al., 2018). Since 2010, the REFAUTS has licensed 11 boats for dolphin-watching (Lunardi et al., 2017). ...
... Although there was a study conducted in the REFAUTS that did not detect behavioral changes in the Guiana dolphins in the presence of tourist boats (Tosi and Ferreira, 2009), other studies conducted in the same area have shown short-term behavioral changes in the Guiana dolphins in the presence of tourist boats (e.g. Leão-Martins et al., 2018). The study by Tosi and Ferreira (2009) . ...
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... (A) Efeitos cumulativos quanto à degradação ecossistêmica. Estes efeitos podem ser agrupados, conforme segue: (Bittencourt et al., 2017;Cremer et al., 2011;Martins et al., 2008). Os comportamentos reprodutivos em mamíferos marinhos são associados à produção de som, às interações sociais e ao padrão e qualidade de alimentação, sendo as alterações no padrão acústico de comunicação fator crucial para dificultar e ou impedir estes comportamentos e a manutenção da dinâmica populacional (Erbe et al., 2016). ...
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... On the other hand, it may also impact the species, as reported around the world (e.g. Lusseau and Higham, 2004;Parsons, 2012;Henneham et al., 2015;New et al., 2015;Senigaglia et al., 2016;Heiller et al., 2016;Perez-Jorge et al., 2016;Silva, 2017), including in studies focused specifically on the S. guianensis in the Brazilian coast (Carrera, 2004;Santos et al., 2006;Filla, 2008;Martins et al., 2016), also in and around the EPAA (Pereira et al., 2007). ...
... Furthermore, dolphins have been observed to alter their whistle characteristics, such as their frequency range, in elevated noise conditions or in the presence of vessels (Morisaka et al., 2005;May-Collado and Wartzok, 2008;Guerra et al., 2014;May-Collado and Quinones-Lebron, 2014;Papale et al., 2015;Heiler et al., 2016;Rako Gospić and Picciulin, 2016;Marley et al., 2017b). Changes to whistle duration have also been reported (May-Collado and Wartzok, 2008;Guerra et al., 2014;May-Collado and Quinones-Lebron, 2014), as have increases in whistle production rates (Scarpaci et al., 2000;Van Parijs and Corkeron, 2001;Buckstaff, 2004;Guerra et al., 2014;Martins et al., 2018). ...
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... Outro fator que pode influenciar nas taxas de emissões acústicas dos golfinhos é a presença de embarcações (May-Collado & Quiñones-Lebrón, 2014;Martins et al., 2018). May-Collado & Quiñones-Lebrón (2014) registraram que, durante atividades de forrageio, os golfinhos alteram o padrão de emissão acústica na presença de embarcações, aumentando a frequência do som, possivelmente para sobrepor o ruído gerado. ...
... May-Collado & Quiñones-Lebrón (2014) registraram que, durante atividades de forrageio, os golfinhos alteram o padrão de emissão acústica na presença de embarcações, aumentando a frequência do som, possivelmente para sobrepor o ruído gerado. Martins et al. (2018) encontraram resultados semelhantes. Os autores perceberam que a faixa de frequência dos ruídos antrópicos (0.43 -35.8 kHz) sobrepõe com as utilizadas pelos golfinhos (1 -48 kHz), causando mudanças na emissão sonora, como o aumento considerável no número de assobios e uma redução nas cadeias de cliques. ...
... Maior atenção tem sido dada ao turismo em zonas costeiras, praias e estuários (Hvenegaard e Barbieri, 2010) e grande parte dos trabalhos existentes se concentra em grupos de organismos aquáticos (e.g. Ferreira e Rosso, 2009;Leão et al., 2016;Lima et al., 2014;Santos et al., 2015). Um estudo sobre o efeito do turismo para observação de botos (Inia geoffrensis) na Amazônia constatou o potencial impacto negativo nos animais e demonstrou a necessidade de melhorias no manejo da atividade (Alves et al., 2013). ...
Thesis
O turismo em áreas protegidas tem crescido nos últimos anos, principalmente em países em desenvolvimento em zonas tropicais. No Brasil, o número de visitantes em Parques Nacionais cresce a cada ano. Apesar dos potenciais benefícios para a conservação, o turismo pode causar impactos negativos capazes de comprometer o desempenho das reservas em sua função principal, a proteção da biodiversidade. Entender as respostas das espécies é fundamental para o manejo da atividade turística garantindo a sua sustentabilidade ecológica. Avaliei o efeito do início do turismo sobre a comunidade de mamíferos terrestres (>1kg) no Parque Nacional Cavernas do Peruaçu (MG). A amostragem ocorreu entre 2011 e 2017, antes e depois do turismo, com uso de armadilhas fotográficas em trilhas com e sem visitação. Busquei responder se o uso das trilhas turísticas pelos mamíferos diminuiu após o início da visitação em relação à antes do turismo e às trilhas não turísticas. Obtive 3221 registros independentes de 23 espécies de mamíferos. Riqueza e composição da comunidade foram similares antes e depois do turismo nas trilhas turísticas. Houve redução na frequência de uso das trilhas pelo total de mamíferos, mas o declínio foi maior nas trilhas sem visitação. A resposta das espécies analisadas individualmente variou com o aumento da intensidade de turistas, sendo que jaguatirica, veado-catingueiro e caititu aumentaram o uso das trilhas turísticas enquanto mocó e paca diminuíram. Não houve um padrão de impacto negativo geral, provavelmente devido à baixa intensidade e início recente do turismo na área, podendo haver um atraso no tempo das respostas. Características próprias das espécies as tornam mais ou menos sensíveis ao turismo e podem explicar suas tendências a evitar ou procurar as trilhas com visitação. O manejo da atividade turística no parque tem sido conduzido de forma a atenuar impactos, e deve permanecer, mas é importante a continuidade do monitoramento uma vez que a visitação tende a aumentar.
... One explanation for this difference between the engines is that the diesel engine generates less direct vibration in water and minor amount of bubbles by the propel- lers' blades, causing noises of lower intensities and at lower frequencies (Seppänen and Nieminen 2004). Another reason is that the number of revolutions per minute in internal diesel engines is less than of the outboard petrol engines, generating less noise and possibly less impact on aquatic life ( Martins et al. 2016). ...
... Therefore, it can be suggested that internal diesel engines are relatively less harmful to the Guiana dolphin, mainly because these animals can shift their signals to higher frequencies and also for the reason that they have fewer hearing sensitivity at low frequencies ( Martins et al. 2016). ...
... In Mississipi, bottlenose dolphins changed their behavior in less than 1 min in the presence of jet-skis, thus Miller et al. (2008) con- cluded that the increase of this activity can cause long-term impacts on dolphins' populations ( Fig. 13.25). Martins et al. (2016) in a study of Guiana dolphin in Pipa beach, in the presence of boats they found changes in all acoustic parameters of the signals. The main changes in whistles and pulsed calls were characterized by the increasing of fre- quencies and the amount of signals emitted. ...
Chapter
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The Sotalia guianensis dolphin occurs in the western Atlantic Ocean, from the south of Brazil to Central America. It is a coastal species, much susceptible to human impacts, as anthropogenic noises, which in general causes potential impacts in marine mammals’ populations, because the emission and reception of sound signals plays a complex and vital role in this populations’ ecology through many different ways. This study reviews the acoustic repertoire and potential anthropic impacts on populations of Guiana dolphin (S. guianensis) through its occurrence, and described and compared the anthropogenic noises with the acoustic repertoire of three Brazilian populations: Cananéia estuary – São Paulo State, Caravelas estuary – Bahia State and Pipa beach – Rio Grande do Norte State. Data was collected similarly in these three sites during boats surveys using hydrophones and audio recorders. Results showed overlapping of the S. guianensis repertoire and noises produced from boats, dredge activities and wood-barges, leading to harm on individuals and populations. This review has gathered important information supporting marine activity management, and can be used to evaluate acoustic impacts over cetaceans population.
... This species may have a higher rate and shorter duration of whistles in noisy environments (Bittencourt et al. 2017). Also, noise can change the initial and final frequency of whistles, as well as reduce the emission of clicks in the environment (Leão Martins et al. 2016). Noise from human sources can mask important acoustic signals and behaviour, alter auditory thresholds, decrease auditory capacity of these animals, and have effects on behaviour, hormones and blood pressure of several species (Gordon et al. 2004;Barber et al. 2009). ...
Article
Cetacean populations can adjust their sound repertoire depending on the environment they are in, their population structure and the activities they are performing. Our goal was to characterize and compare, qualitatively and quantitatively, the sound repertoire of Sotalia guianensis in two areas of south-eastern and southern Brazil. We expected to find similar sound repertoires between the two regions, as they are geographically close and are part of the same complex estuarine. Acoustical parameters of the whistles, burst pulses and clicks were recorded during both daytime and night-time hours. They were compared between areas through Chi-square and Mann–Whitney tests. The samples resulted in 3,630 recorded whistles, 631 burst pulses and 44 low-frequency narrow-band sounds, with echolocation clicks present in 50.98% of the total minutes analysed. The occurrence rate of all sounds and the acoustic parameters of the whistles and clicks differed between the two areas, so our initial hypothesis was rejected. We highlighted environmental differences, behaviour exhibited by animals, number of individuals and group size and low exchange of individuals between areas as possible explanations that might account for these results, based on our knowledge of the species and areas of study, as well as a substantial literature on the physical and biological characteristics of the sounds.