Common dolphin ( Delphinus delphis) habitat preferences using data from two platforms of opportunity

• Published in: Acta oecologica (Montrouge) Vol. 38; pp. 24 - 32
• Main Authors: Moura, André E., Sillero, Neftalí, Rodrigues, Ana
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Masson SAS 2012; Elsevier
• Subjects: Animal and plant ecology; Animal, plant and microbial ecology; biogeography; Biological and medical sciences; Cetacea; chlorophyll; coasts; Common dolphin; Delphinus; Delphinus delphis; dolphins; Ecological niche modelling; fish; Fundamental and applied biological sciences. Psychology; General aspects; General aspects. Techniques; habitat preferences; habitats; Marine; Maxent; Methods and techniques (sampling, tagging, trapping, modelling...); Portugal; Portugal; Europe; ANE, Portugal; Common dolphin; Maxent; Cetacea; Portugal; Ecological niche modelling; Vertebrata; Mammalia; Delphinus delphis; Ecological niche; Habitat selection; Modeling
• ISSN: 1146-609X; 1873-6238
• DOI: 10.1016/j.actao.2011.08.006

Cetaceans are difficult to observe in the wild, and demand complex logistics for dedicated collection of biological data. As such, the distribution of most cetacean species is still poorly understood. Ecological niche models are useful in studying species distributions and their ecological determinants, and platforms of opportunity (e.g. commercial nautical operators) can provide an alternative source for that data in cetaceans. In this study, we modelled common dolphin ( Delphinus delphis) habitat preferences using ecological niche modelling and presence data obtained from distinct platforms of opportunity in two different areas in the Portuguese coast (west and south mainland Portugal) for the period 2005–2007. Models from southern Portugal were projected to western Portugal and vice-versa, to check for robustness in predicting the species ecological niche. Our results show that data from platforms of opportunity can result in robust ecological models and provide extremely useful information on cetacean ecology. We found that common dolphins exhibit a patchy distribution pattern over the Portuguese coastline, and identified key habitats for their occurrence. The most important variable associated with this species' distribution was chlorophyll concentration which, given the results from previous research, we hypothesise reflects an ecological specialisation on pelagic schooling fish. Given that the most abundant schooling fish species in Portugal is increasingly overexploited and in constant decline, more attention should be given to the conservation of common dolphin in Portuguese waters. ► We modelled common dolphin ecological niche from different opportunity data sources. ► We compared the reliability of both data sources as compared to dedicated surveys. ► Chlorophyll concentration was the most important variable for both data sources. ► This supports previous studies showing ecological specialization in schooling fish. ► This specialization should be considered in evaluating the species conservation needs.