Research reveals new distance record for British dolphins

Research presented by scientists from Earthwatch at the annual conference of the European Cetacean Society in Turkey recently revealed that bottlenose dolphin (Tursiops truncatus) identified in the Moray Firth in northeast Scotland have been tracked to locations as far afield as Cork and Galway on the coast of Ireland, over 1,300km away, representing a new point to point distance record for this species.*

Earthwatch scientists Kevin Robinson of the Cetacean Research & Rescue Unit (CRRU) and Peter Stevick of the Hebridean Whale and Dolphin Trust (HWDT) were co-authors of the report, which has profound implications for the effectiveness of current conservation measures.

The Moray Firth bottlenose dolphin population is one of the two major resident groups of bottlenose dolphin in British waters. Current threats to this population include the development of new marinas, with a predicted increase in boat traffic; exploration and extraction of new and existing fossil fuel deposits, some of which are in and adjacent to an existing Special Area of Conservation; and marine renewable energy developments, including a large offshore wind farm proposed for the outer Moray Firth.

Kevin Robinson has been working with teams of Earthwatch volunteers to monitor dolphin populations in the Moray Firth region for many years. Photo identification of individuals' dorsal fins is the principal method used in the study. HWDT has also been carrying out surveys of whales and dolphins from its research yacht off the west coast of Scotland for several years with Earthwatch volunteers.

Robinson says, "Working with colleagues at the University of Aberdeen to cross-match photo-identification catalogues, a number of matches became apparent with individuals recorded by HWDT on the west coast of Scotland. A total of six distinctively marked animals were positively identified between the two study sites. After further consultation with colleagues from Ireland, at least three of these were also confirmed off the coasts of Cork and Galway."

Explaining the significance of the findings, Robinson says, "Until recently, research has suggested that these dolphins have relatively small home ranges and that the Moray Firth bottlenose population was isolated in the North Sea. Similarly it was thought likely that the Hebridean dolphins were confined to the west coast of Scotland. These findings are therefore believed to be highly significant to our current understanding of movement and genetic mixing between neighbouring bottlenose communities. They will also contribute to our understanding of overall distribution of bottlenose dolphin in western European waters."

"The new findings further raise concerns that the current Special Area of Conservation in the Moray Firth is only protecting a small proportion of the habitat that these highly mobile marine mammals use. The results probably raise more questions than provide answers at this stage, but as investigations continue, the respective teams hope to publish a more comprehensive report of these findings in the near future."

Nat Spring, Earthwatch's Senior Research Director says, "This significant finding is a terrific example of how conducting long term research and the power of collaborative photo-identification studies can lead to discoveries which are crucial for informing conservation strategies."

Read more about Earthwatch research in Scotland: 'Super-pod' sighting suggests dolphins are moving north due to climate change. 

Notes to editors

*Robinson K.P., Cheney B., Mandleberg L., Eisfeld S.M., Costa M., Johnston P. & Stevick P.T. (2009) Coast to coast: First evidence for translocational movements by Scottish bottlenose dolphins. 23rd Annual Conference of the European Cetacean Society, Istanbul, Turkey, 2-4 March 2009 (link: http://www.crru.org.uk/research/papers/robinson_etal_ECS2009.pdf)

Earthwatch

HDWT

HWDT was part of a major three-year research collaboration between Scottish universities to find out more about the populations of bottlenose dolphins in Scotland. Through this, much more was discovered about the dolphins on the west coast, which also appear to be a resident - if small - population.