Distribution and habitat modelling of common dolphins (Delphinus delphis) in the eastern North Atlantic
Correia, A.M.; Gil, A.; Valente, R.; Rosso, M.; Pierce, G.J.; Sousa Pinto, I. (2019). Distribution and habitat modelling of common dolphins (Delphinus delphis) in the eastern North Atlantic. J. Mar. Biol. Ass. U.K. 99(06): 1443-1457. https://dx.doi.org/10.1017/s0025315419000249
In: Journal of the Marine Biological Association of the United Kingdom. Cambridge University Press/Marine Biological Association of the United Kingdom: Cambridge. ISSN 0025-3154; e-ISSN 1469-7769, more
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| Keywords |
Distribution > Temporal distribution
Ocean space > High seas
Spatial distribution
Cetacea [WoRMS]; Delphinus delphis Linnaeus, 1758 [WoRMS]
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| Author keywords |
Cetaceans, ecological modelling, Macaronesia |
| Authors | | Top | Dataset |
- Correia, A.M.
- Gil, A.
- Valente, R.
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- Rosso, M.
- Pierce, G.J.
- Sousa Pinto, I.
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| Abstract |
The eastern North Atlantic (ENA) has many highly productive areas where several species of cetaceans have been recorded, with the common dolphin (Delphinus delphis) being one of the most frequently sighted species. However, its spatial and temporal distribution in high seas is poorly known. The study presents the results from 5 years of cetacean monitoring in the ENA (2012–2016) aboard cargo ships that follow the routes from Continental Portugal to the Macaronesian archipelagos and north-west Africa. Common dolphin was the most frequently sighted cetacean with 192 occurrences registered on effort and an overall encounter rate of 0.36 sightings/100 nmi. The species was distributed in coastal and offshore waters, but absent from the Canaries and Cape Verde islands. Statistical ‘habitat’ models were developed to describe and explain the occurrence of sightings of the species: variables affecting detection of dolphins had a small impact and there were clear spatiotemporal distribution patterns, influenced to some degree by environmental variables. Predicted probability of occurrence was highest in coastal waters of continental Portugal and around the Azores. The models, combined with maps of distribution, were useful to identify important areas for the species, which could be the focus of future conservation efforts. Common dolphin presence was related to depth, distance to coast and seamounts, seabed slope, chlorophyll concentration, sea-surface temperature and sea level anomalies; the possible ecological significance of these relationships is explored. |
| Dataset |
- CETUS: Cetacean monitoring surveys in the Eastern North Atlantic, more
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