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Bottlenose dolphin
Tursiops truncatus

European Eel
Anguilla anguilla

Loggerhead Sea Turtle
Caretta caretta

Cory’s Shearwater
Calonectris diomedea

The dolphin that everyone knows!
The bottlenose dolphin is the best known of all cetaceans. It figured in the legends of ancient Greeks and Romans in the past and, is a well-known star of movies and television shows, (Perrin et al, 2009, Mead et al, 2002). In the wild, some individuals have developed social interactions with humans, such as cooperating with fishermen in the capture of prey (Perrin et al, 2009).

This species inhabits most warm temperate and tropical shorelines, adapting to a variety of marine and estuarine habitats, even ranging into rivers. They are primarily coastal but are also found in pelagic waters, near oceanic islands, and over the continental shelf (Perrin et al, 2009). There appear to be two main varieties of this species: a smaller, inshore form, and an oceanic one, larger and more robust that lives mainly offshore (Shirihai and Jarret, 2006, Carwardine, 2002).

Bottlenose dolphins have very fluid social groups. In their fission–fusion society, group composition changes very quickly. However, some long-term relationships have been documented with individuals sighted together for years at a time. They are typically found in groups of 2–15 individuals, although groups of more than 1000 have been reported (Perrin et al, 2009).

Threats of human origin include entanglement in nets, entanglement in or ingestion of recreational fishing gear, pollution, boat collisions, noise, tourism and direct hunt (Perrin et al, 2009).

Although there are many threats operating on local populations, bottlenose dolphins are widespread and abundant, and as a species it does not appear to merit concern for major global population decline (Perrin et al, 2009). The species is listed in Annex II of Habitats Directive (Natura 2000 network) and Appendix II of CITES. EU governments, throughout the Habitats Directive, are required to consider the areas where this species occurs for the establishment of Special Areas of Conservation (SACs; Cañadas 2006; Wilson et al. 1997).

Interesting facts
- Bottlenose dolphins can reach 4.1 meters in length and weight 650kg (Shirihai and Jarret, 2006).
- Female common bottlenose dolphins can live to more than 57 years, and males up to 48 years (Perrin et al, 2009).
- They produce a large variety of whistles, including “signature whistles” that are individually specific and appear to be used to communicate identity, location, and possibly emotional state (Perrin et al, 2009).
- Bottlenose dolphins are one of the few species, besides humans, that can recognize themselves in mirrors (Perrin et al, 2009).

Perrin, W. F., Würsig, B., Thewissen, J.G.M. (Eds.), 2009. Encyclopaedia of marine mammals, second ed. Academic Press, Amsterdam, 1316pps.
Shirihai, H., Jarret, B., 2006. Whales, Dolphins and Seals – A Field Guide to the Marine Mammals of the World, A&C Black, London, 384pps.
Cañadas, A. (2006). Towards the conservation of dolphins in the Alborán Sea. PhD thesis, University Autónoma de Madrid.
Wilson B, Thompson P. M., Hammond, PS (1997) Habitat use by bottlenose dolphins: seasonal distribution and stratified movement patterns in the Moray Firth, Scotland. Journal of Applied Ecology, 34: 1365-1374.
Mead, J. G., Gold, J. P., 2002. Whales and Dolphins in Question, The Smithsonian Answer Book, Smithsonian Institution Press, Washington and London, 200pps.
Carwardine, M., 2002. Whales, Dolphins and Porpoises, Dorling Kindersley Publishing, London, 255pps.

Tursiops truncatus Risk

Alberto Molina Serrano
Volunteer for ANSE

How did you get involved?
Although I had heard about ANSE, I did not start to collaborate with them until I made a course of identification of cetacean and seabirds. Since then, I have participated in three different campaigns with dolphins. Recently I’ve started to help with birds ringing as well.


This Project has been funded by the Erasmus Plus Programme, with support from the European Commission

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