Browsing by Author "Fernandez, Marc"
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- Analysis of residence patterns of Sperm whales (Physeter macrocephalus) in Azores Islands using opportunistic dataPublication . Oliveira, Beatriz; Fernandez, Marc; Azevedo, José M. N.Sperm whales are one of the main targets of the whale watching operations on the Azores archipelago. Observations made from commercial platforms, many of which collected in the context of the MONICET project, provide a low-cost and large dataset from which to study this species. The aim of this study is to analyze the residence patterns of sperm whales in selected areas of the Azores archipelago. Data was collected from 2005 to 2012 and comprises two different geographic areas (the islands of Pico Island and of Sao Miguel). A total of 1133 photographs were obtained from different opportunistic platforms and pooled together in a common database. Animals were individually identified using photo-identification methods. Residence times were analyzed by plotting lagged identification rates against time lag and fitting a series of population models implemented in Socprog 2.4 program. Selection of the best fitting models was determined using the lowest Quasi Akaike Information Criterion (QAIC) value. A total of 391 animals were identified in Pico (resighting rate of 27%) and 199 animals were identified in Sao Miguel (resighting rate of 23%). Some of the individuals have been resighted in both islands suggesting the existence of movements between islands. Preliminary results show that sperm whales spend 14.13 days around Sao Miguel Island and 4.12 days around Pico Island. Expected results will elucidate if there is a meaningful population exchange between islands.
- Aqua : Leveraging Citizen Science to Enhance Whale-Watching Activities and Promote Marine-Biodiversity AwarenessPublication . Dionisio, Mara; Mendes, Mafalda; Fernandez, Marc; Nisi, Valentina; Nunes, NunoLife-supporting ecosystems are facing impending destruction. The human-computer interaction (HCI) community must rethink how to design technological interventions that reconcile concepts and theories for ecological computing. Proponents of sustainable HCI have pushed for tools and systems that aim to decenter the human in a shift toward post human design-a theoretical approach that challenges the assumption that only humans are stakeholders of technology as it increasingly shapes the future. Building on the iconic value of whales and the economic impact of whale watching as a form of ecotourism, we developed Aqua, a digital tool that leverages the potential of citizen science to engage tourists in marine-biodiversity awareness and conservation. This manuscript is advancing the field of sustainable HCI and tourism applications in two ways: first, we deliver an artefact contribution by designing and implementing a digital tool to enhance whale-watching activities. Second, we offer an empirical research contribution through observation and data gathering while comparing participants’ experiences of a whale-watching trip with and without the digital tool. Finally, preliminary insights are provided to inform the design of future digital tools aimed at promoting environmental conservation and citizen-science approaches among tourists. This work presents progression in understanding and informs the design of digital tools to engage tourists in novel and sustainable experiences.
- AzoresPhotoID: first results from an open-access photoidentification cataloguePublication . Sardà, Clara; Fernandez, Marc; Parker, Adam; Soley, Raquel; Azevedo, José M. N.The Archipelago of the Azores is a group of oceanic islands located in the middle of the Atlantic Ocean, due its own characteristics can be considered as a cetacean biodiversity "hot spot", with 27 species of cetaceans identified. The AzoresPhotoID catalog uses photos contributed by the local whale and dolphin watching operators, from tourists and from local researchers. An off-line database was constructed using commercial image processing software. However the catalog has an online version, based on blogging and image sharing platforms (http://azoresphotoid.blogspot.com/for communication and http://www.flickr.com/azoresphotoid/ for the catalog itself). Images and the associated data are available on a Attribution-NonCommercial-ShareAlike Creative Commons license. From 2003 to 2010 nearly 700 individuals have been catalogued, from seven different species: Megaptera novaeangliae, Tursiops truncatus, Globicephala macrorhynchus, Grampus griseus, Balaenoptera borealis, Balaenoptera physalus and Physeter macrocephalus. From these, more than twenty individuals have been resighted at least once. The analysis of the catalogue showns that Bottlenose Dolphins, Sperm Whales and Risso’s Dolphins seem to have a pattern of interannual sightings, what suggests the preference of the Azorean waters for some individuals. This study shows that opportunistic images can be a valuable photo-identification resource.
- Behavioural Ecology Traits of Elusive Deep-Diver Whales Unravel a Complex Social Structure Influenced by Female Philopatry and Defence PolygynyPublication . Badenas, Anja; Dinis, Ana; Ferreira, Rita; Sambolino, Annalisa; Hamard, Eliette; Berninsone, Leonardo G.; Fernandez, Marc; Alves, Filipe M. A.Knowledge of the role of individual associations has provided an insightful understanding of the structures of animal societies, especially in highly social mammals such as primates. Yet, this is unbalanced towards marine mammals, particularly to beaked whales, due to their elusive nature. In addition, information on the fundamental drivers of the social structure of these deep-diving animals is still scarce. Here, the hypothesis of female defence polygyny was tested in Blainville’s beaked whales (Mesoplodon densirostris) and discussed within the context of marine and terrestrial organisms displaying similar patterns, by (i) estimating residency times to obtain information on the movements into and out of the area, (ii) analysing social networks to assess individual association metrics, (iii) measuring the strength of the associations to assess the existence of preferred or avoided relationships among individuals, and (iv) modelling different social structures to address temporal patterns in social relationships. Using a 9-year photographic dataset derived from the pelagic habitat, individual associations were inferred based on likelihood techniques. This approach allowed to infer on the species’ social structure in relation to age class, sex, residency status, and spatio-temporal patterns, which can be a good practice to be applied for other taxa. Heterogeneity in capture probability and residency times was observed between age-sex classes, with adult females exhibiting long-term site fidelity. This suggests different habitat roles and spatial structuring within this social organisation. Strong and long dyadic associations occurred between adult females and immatures, contrarily to between males, and the best-fitting models of the temporal patterns suggested long-lasting and temporary associations. The present findings unravel a complex social structure stratified by age-sex class and influenced by female philopatry and defence polygyny, like an unimale group mating system, which varies from other beaked whales but is similar to some birds, pinnipeds, or non-human primates.
- CIRN/GREC 2013 Campaign reportPublication . Fernandez, Marc; Gannier, Alexandre; Azevedo, José M. N.A cetacean survey campaign was performed around São Miguel Island (Azores) by Anacaona Sailing boat (GREC) from July 13th to August 24th of 2013. The team conducted a total of 22 days of effort around the island. A total of 8 species was sighted during the survey: common dolphin (Delphinus delphis), atlantic spotted dolphin (Stenella frontalis), bottlenose dolphin (Tursiops trucnatus), stripped dolphin (Stenella coeruleoalba), risso’s dolphin (Grampus griseus), sperm whale (Physter macrocephalus), sei whale (Balaenoptera borealis) and beaked whales (Mesoplodon sp.). The common dolphin together with the atlantic spotted dolphin were the most sighted species. Some differences in the distribution between the species can be appreciated in the corrected effort maps. Acoustic data is currently under study.
- CIRN/GREC 2014 Campaign reportPublication . Fernandez, Marc; Gannier, Alexandre; Azevedo, José M. N.A cetacean survey campaign was performed around São Miguel Island (Azores) by Anacaona Sailing boat (GREC) from May 8th to May 17th and from July 4th to August 1st of 2014. The team conducted a total of 18 days of effort around the island. A total of 9 species were sighted during the survey: common dolphin (Delphinus delphis), atlantic spotted dolphin (Stenella frontalis), bottlenose dolphin (Tursiops trucnatus), stripped dolphin (Stenella coeruleoalba), risso’s dolphin (Grampus griseus), sperm whale (Physter macrocephalus), fin whale (Balaenoptera physalus), false killer whale (Pseudorca crassidens) and Blainville beaked whale (Mesoplodon densirostris). The common dolphin together with the Atlantic spotted dolphin were the most sighted species. Some differences in the distribution between the species can be appreciated in the corrected effort maps. Acoustic data is currently under study.
- Climate change vulnerability of cetaceans in Macaronesia : Insights from a trait-based assessmentPublication . Sousa, Andrielly O.; Alves, François; Arranz, Patricia; Dinis, Ana; Fernandez, Marc; González García, L.; Morales, Manuel B.; Lettrich, Matthew D.; Coelho, R. Encarnação; Costa, H.; Lourenço, T. Capela; Azevedo, José M. N.; Santos, C. FrazãoOver the last decades global warming has caused an increase in ocean temperature, acidification and oxygen loss which has led to changes in nutrient cycling and primary production affecting marine species at multiple trophic levels. While knowledge about the impacts of climate change in cetacean's species is still scarce, practitioners and policymakers need information about the species at risk to guide the implementation of conservation measures. To assess cetacean's vulnerability to climate change in the biogeographic region of Macaronesia, we adapted the Marine Mammal Climate Vulnerability Assessment (MMCVA) method and applied it to 21 species management units using an expert elicitation approach. Results showed that over half (62%) of the units assessed presented Very High (5 units) or High (8 units) vulnerability scores. Very High vulnerability scores were found in archipelago associated units of short-finned pilot whales (Globicephala macrorhynchus) and common bottlenose dolphins (Tursiops truncatus), namely in the Canary Islands and Madeira, as well as Risso's dolphins (Grampus griseus) in the Canary Islands. Overall, certainty scores ranged from Very High to Moderate for 67% of units. Over 50% of units showed a high potential for distribution, abundance and phenology changes as a response to climate change. With this study we target current and future information needs of conservation managers in the region, and guide research and monitoring efforts, while contributing to the improvement and validation of trait-based vulnerability approaches under a changing climate.
- Differences in spatial distribution of two small delphinids (Delphinus delphis and Stenella frontalis) in two islands of the Azores ArchipelagoPublication . Fernandez, Marc; Oviedo, L.; Hartman, Karin L.; Sousa, B.; Azevedo, José M. N.The archipelago of the Azores represents a special area of cetacean ocurrence, mostly due to its oceanic nature. In this area two small delphinids, the common dolphin and the Atlantic spotted dolphin, the former seeming to be present all year around, while the latter seems to be seasonal (summer). In this study we analyse their respective distribution in two different islands, Pico and São Miguel. Sighting records from 2005 to 2008 in Pico, and from 2008 in São Miguel, were pooled together, analyzed and incorporated into a Geographic Information System (ArcGis 9.3). In order to understand the relations between these species and the ecogeographical variables, a statistical treatment (Kruskal-Wallis) and an Ecological Niche Analisis (using Biomapper 4) were perfomed. While common dolphins and Atlantic spotted dolphins are statistically related with depth and slope in Pico, they are just statiscally related with depth in São Miguel. Moreover there are statiscal differences between their distribution in the two islands, suggesting differences on the ecological niche of the species depending on the island, probably related with differences on bathymetry features. There are also differences in distribution between common dolphins and Atlantic spotted dolphins in São Miguel, while in Pico they seem to cohabit in the same area, possibly indicating a niche overlap. In São Miguel, statiscal differences in the distribution between the two species (in depth and in slope) are present, atlantic spotted dolphins showing more tolerance to deep waters. These results suggest the existence of differences on these two delphind populations’ distributions depending on the island, probably due to different bathymetric features. Further work is being conducted in order to better understand their distribution and interactions.
- Dolphin whistle repertoires around São Miguel (Azores) : Are you common or spotted?Publication . Gannier, Alexandre; Fuchs, Sandra; Gannier, Adrien; Fernandez, Marc; Azevedo, José M. N.Short-beaked common dolphins (Delphinus delphis) and Atlantic spotted dolphins (Stenella frontalis) are both common in the Azores archipelago during summer. Because both species are sympatric, at least in part of their range, they may use acoustic features to recognize conspecifics and maintain school cohesion throughout their different activities. Delphinid whistles were recorded with a 96-kHz sampling rate using towed hydrophone system during surveys held in summer of 2013 and 2014 around São Miguel Island (Azores, Portugal). A total of 256 whistles attributed to either short-beaked common dolphin (n = 133) or Atlantic spotted dolphin (n = 123) were selected and processed with a contour extraction software. Elementary statistical analysis showed that duration, frequency and slope variables were significantly different for both species, although in most cases their range overlapped. We performed a discriminant analysis to test species classification: the dataset was randomly split into one calibration subset (186 whistles) and one validation subset (70 whistles). The discriminant analysis retained four variables (global slope, duration, minimal and final frequencies) as useful for classification. The discriminant function resulted in correct classification rates of 78.5% (calibration subset) and 81.4% (validation subset). Common dolphin whistles were better classified than Atlantic spotted dolphin whistles (83.4% and 74.8%) respectively. This study shows that reliable species identification can be achieved for common and spotted dolphins using their whistle repertoire characteristics.
- Estudando e valorizando os cetáceos dos AçoresPublication . Cecchetti, Arianna; Fernandez, Marc; Azevedo, José M. N.Nos Açores ocorrem pelo menos 25 espécies diferentes de cetáceos (baleias e golfinhos). Algumas podem observar-se facilmente durante todo o ano, mas outras são menos visíveis, quer por ocorrerem apenas em épocas específicas quer pelo seu comportamento furtivo. Todas as espécies de cetáceos estão protegidas legalmente, e algumas têm um estatuto de conservação que requer medidas especiais de gestão. Estas medidas requerem, no entanto, conhecimentos de base sobre abundância e distribuição que infelizmente é insuficiente. Para além dos argumentos conservacionistas os cetáceos constituem um recurso económico relevante para o sector do turismo nos Açores. Por esta razão torna-se ainda mais importante o seu estudo: só um bom conhecimento dos padrões de distribuição e de comportamento permitirá garantir uma boa gestão do recurso. […].
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