Browsing by Author "Santos, Manuel Eduardo dos"
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- Bray calls emitted by common bottlenose dolphins (Tursiops truncatus) in offshore waters of northeastern BrazilPublication . Lima, Alice; Cunha Lopes, Lara; Melo, Jéssica; Fróes, Evelyn; de Cassia De Carli, Rita; Bassoi, Manuela; Sousa‐Lima, Renata S.; Santos, Manuel Eduardo dos; Gonçalves, Maria Isabel Carvalhoinexistente
- Brays and bits: Information theory applied to acoustic communication sequences of bottlenose dolphinsPublication . Luís, Ana Rita; Alves, Inês Sofia Carvalho Alves; Sobreira, Filipa Veiga; Couchinho, Miguel Nogueira; Santos, Manuel Eduardo dosAcoustic call sequences are important components of vocal repertoires for many animal species. Bottlenose dolphins (Tursiops truncatus) produce a wide variety of vocalizations, in different behavioural contexts, including some conspicuous vocal sequences – the ‘bray series’. The occurrence of brays is still insufficiently documented, contextually and geographically, and the specific functions of these multi-unit emissions are yet to be understood. Here, acoustic emissions produced by bottlenose dolphins in the Sado estuary, Portugal, were used to provide a structural characterization of the discrete elements that compose the bray series. Information theory techniques were applied to analyse bray sequences and explore the complexity of these calls. Log-frequency analysis, based on bout criterion interval, confirmed the bout structure of the bray series. A first-order Markov model revealed a distinct pattern of emission for the bray series’ elements, with uneven transitions between elements. The order in these sequential emissions was not random and consecutive decreases in higher order entropy values support the notion of a well-defined structure in the bray series. The key features of animal signal sequences here portrayed suggest the presence of relevant information content and highlight the complexity of the bottlenose dolphin’s acoustic repertoire.
- Cetaceans of the cape verde archipelagoPublication . Reiner, Francisco; Santos, Manuel Eduardo dos; Wenzel, Frederick W.; Whale, Alliedinexistente
- Changes in the acoustic behavior of resident bottlenose dolphins near operating vesselsPublication . Luís, Ana Rita; Couchinho, Miguel N.; Santos, Manuel Eduardo dosPublished for the Society for Marine Mammalogy, Marine Mammal Science is a source of significant new findings on marine mammals resulting from original research on their form and function, evolution, systematics, physiology, biochemistry, behavior, population biology, life history, genetics, ecology and conservation. The journal features both original and review articles, notes, opinions and letters. It serves as a vital resource for anyone studying marine mammals.
- Correction: D-Track—A semi-automatic 3D video-tracking technique to analyse movements and routines of aquatic animals with application to captive dolphinsPublication . Rachinas-Lopes, Patrícia; Ribeiro, Ricardo; Santos, Manuel Eduardo dos; Costa, Rui M.There is an error in the XML that is causing the third author’s name, Rui M. Costa, to be indexed incorrectly. The name should be indexed as Costa, Rui M. The correct citation is: Rachinas-Lopes P, Ribeiro R, dos Santos ME, Costa RM (2018) D-Track—A semi-automatic 3D video-tracking technique to analyse movements and routines of aquatic animals with application to captive dolphins. PLoS ONE 13(8): e0201614. https://doi.org/10.1371/journal.pone. 0201614.
- D-Track—A semi-automatic 3D video-tracking technique to analyse movements and routines of aquatic animals with application to captive dolphinsPublication . Lopes, Patrícia Rachinas; Ribeiro, Ricardo; Santos, Manuel Eduardo dos; Costa, Rui MiguelScoring and tracking animal movements manually is a time consuming and subjective process, susceptible to errors due to fatigue. Automated and semi-automated video-based tracking methods have been developed to overcome the errors and biases of manual analyses. In this manuscript we present D-Track, an open-source semi-automatic tracking system able to quantify the 3D trajectories of dolphins, non-invasively, in the water. This software produces a three-dimensional reconstruction of the pool and tracks the animal at different depths, using standard cameras. D-Track allows the determination of spatial preferences of the animals, their speed and its variations, and the identification of behavioural routines. We tested the system with two captive dolphins during different periods of the day. Both animals spent around 85% of the time at the surface of the Deep Area of their pool (5-meters depth). Both dolphins showed a stable average speed throughout 31 sessions, with slow speeds predominant (maximum 1.7 ms-1). Circular swimming was highly variable, with significant differences in the size and duration of the "circles", between animals, within-animals and across sessions. The D-Track system is a novel tool to study the behaviour of aquatic animals, and it represents a convenient and inexpensive solution for laboratories and marine parks to monitor the preferences and routines of their animals.
- Effects of a dolphin interaction program on children with autism spectrum disorders – an exploratory researchPublication . Salgueiro, Emílio Eduardo Guerra; Nunes, Laura; Barros, Alexandra; Maroco, João; Salgueiro, Ana Isabel; Santos, Manuel Eduardo dosBackground: Interaction programs involving dolphins and patients with various pathologies or developmental disorders (e.g., cerebral palsy, intellectual impairment, autism, atopic dermatitis, post-traumatic stress disorder, depression) have stimulated interest in their beneficial effects and therapeutic potential. However, the true effects observed in different clinical and psycho-educational setups are still controversial. Results: An evaluation protocol consisting of the Childhood Autism Rating Scale (CARS), Psychoeducational Profile-Revised (PEP-R), Autism Treatment Evaluation Checklist (ATEC), Theory of Mind Tasks (ToM Tasks) and a custom-made Interaction Evaluation Grid (IEG) to evaluate behavioural complexity during in-pool interactions was applied to 10 children diagnosed with Autism Spectrum Disorders. The ATEC, ToM Tasks and CARS results show no benefits of the dolphin interaction program. Interestingly, the PEP-R suggests some statistically significant effects on ‘Overall development score’, as well as on their ‘Fine motor development’, ‘Cognitive performance’ and ‘Cognitive verbal development’. Also, a significant evolution in behavioural complexity was shown by the IEG. Conclusions: This study does not support significant developmental progress resulting from the dolphin
- Feeding behaviour of the bottlenose dolphin, Tursiops truncatus ( Montagu, 1821 ) in the Sado estuary, Portugal, and a review of its prey speciesPublication . Santos, Manuel Eduardo dos; Coniglione, Chiara; Louro, SóniaComportamento alimentar do golfinho-bico-de-garrafa, Tursiops truncatus ( Montagu, 1821 ) no estuário de Sado, Portugal e uma revisão de suas espécies de presas. O objetivo desse artigo é apresentar a informação disponível acerca do comportamento alimentar e da dieta dos golfinhos-bico-de-garrafa residentes no estuário de Sado, em Portugal. Os golfinhos-bico-de-garrafa são predadores oportunistas, com uma dieta diversificada que inclui crustáceos, cefalópodes e peixes pelágicos e bentônicos, de acordo com a disponibilidade e abundância. A observação direta dos comportamentos alimentares, apoiada por registros fotográficos e videofotográficos, permitiu a identificação de algumas das espécies de presas do golfinho desta região, nomeadamente a enguia-europeia, taínhas, o choco-comum e o polvo. Uma lista de espécies de presas mais comuns dos golfinhos-bico-de-garrafas em diversas regiões foi comparada com as espécies de peixes e cefalópodes que ocorrem no estuário do Sado. Esta comparação levou à uma elaboração de uma lista adicional de espécies que provavelmente também são presas dos golfinhos na região. A observação de comportamentos alimentares foi mais frequente nas partes mais rasas da área de estudo, onde deverá ser mais fácil encontrar e capturar presas.
- Influence zones of pile-drive noise on a resident population of bottlenose dolphins in the Sado estuary, PortugalPublication . Luís, Ana Rita; Silva, C.; Andrade, Fabiana Fontenelle de; Santos, Manuel Eduardo dosInexistente
- Mark-recapture abundance estimate of tucuxi dolphins (Sotalia fluviatilis) in a lake system of the Central AmazonPublication . Coimbra, Zulmira H.; Assis, Carlos A.; Silva, Vera M. F. da; Santos, Manuel Eduardo dosThe tucuxi (Sotalia fluviatilis) is a small dolphin endemic to the Amazon River basin. Because the abundance and trends are currently unknown for the species, this study aimed to estimate its abundance in a lake system of the Central Amazon. A total of 10 two-day sampling periods were carried out from March to June of 2013 throughout a 13.5 km2 area in the Mamiraua Reserve. In the 104 encounters with the species, a minimum number of 389 dolphins were sighted and photographed, which allowed the positive identification of 49 individuals. Mark-recapture models were used to estimate an abundance of 119 individuals (95% CI = 105–150) (corrected for the proportion of identifiable individuals). This is the first estimation of S. fluviatilis abundance using mark-recapture analyses and, together with the photo-id catalog made available, provides a useful reference for future studies regarding tucuxi dolphins.
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