UK dolphins travel much further than previously thought

Chris, one of the bottlenose dolphins known from Cardigan Bay. Credit Sea Watch

August 2009. Two decades of research have revealed the UK's two resident coastal populations of bottlenose dolphins are both more widely traveled than previously thought; according to the marine research charity Sea Watch.

Photo ID surveys
The charity reports that photo-identification surveys over many years around the coast have provided vital evidence in understanding the movements of the two main coastal populations, one of which is off the coast of West Wales in Cardigan Bay, and the other in eastern Scotland, particularly within the Moray Firth. Bottlenose dolphins in the Moray Firth are now known to have travelled more than 800 miles to the coast off Galway and Cork.

Dr Evans said; "This discovery provides highly significant information on bottlenose dolphin movements and questions our current understanding of movements and mixing between the different bottlenose communities. It also raises the question as to whether these long-ranging movements of bottlenose dolphins in UK waters are actually more common than we think."

Welsh dolphins visit Liverpool
In Cardigan Bay, recent data has revealed that bottlenose dolphins have been travelling close to the coasts of NW England, having been sighted on the edge of Liverpool Bay, to add to earlier sightings of recognised Cardigan Bay animals off the Isle of Man.

Sea Watch director Peter Evans said: "Our surveys and photo ID research are revealing just how far the bottlenose dolphins from Cardigan Bay can range not just in winter but in summer too.

"There here been several sightings of groups of more than 20 bottlenose dolphins off the north and east coasts of Anglesey, and now off Rhyl, one of the more easterly locations for the species in the Irish Sea.

Wind farm concerns
"These sightings have important implications for the wind farm developments at nearby North Hoyle and Gwynt y Mor since there has been cause for concern over possible disturbance during both the construction and production phases. Under the EU Habitats Directive, bottlenose dolphins require specific protective measures and that's why two of three SACs in UK were created in Cardigan Bay for the species. However, we now know that the Cardigan Bay animals are regularly coming here as well, so that conservation management must extend to this region."

Recent collaboration between research and conservation groups has also revealed that the Moray Firth bottlenose dolphins, previously believed to be an isolated population, with limited ranging patterns within the north-western North Sea region, have also been travelling.

Long distance travellers
Barbara Cheney, from the Aberdeen University Lighthouse Field Station (AULFS), compared the dorsal fin records of the dolphins recently photographed by Sea Watch regional coordinator Robin Petch off Whitby with their own Moray Firth catalogue and found a match, making this the most southerly known movement of that individual in the North Sea (members of this population have been recorded increasingly travelling south along the east coast of Scotland and into NE England). Furthermore, images collected by the conservation organisations CRRU (Cetacean Research and Rescue Unit) and HWDT (Hebridean Whale & Dolphin Trust) reveal the very first evidence of a movement of animals between geographically separate communities.

Moray dolphins seen off Ireland, Mull & Skye - And even Cornwall?
There were positive matches of individuals from the Moray Firth later photographed around the islands of Mull and Skye in the Inner Hebrides (a distance of the most direct coastal route that the dolphins could have travelled, of around 320 miles), and then by the Irish Whale & Dolphin Group off the coast of Counties Galway and Cork  in southern Ireland, during 2007 and 2008 (a distance of more than 800 miles). There is also even a possible match of one of the Moray Firth dolphins to an animal that was regularly seen off Cornwall in the mid 1990s.

In total, 28 different species of whales, dolphins and porpoises have been recorded in UK and Irish waters, with 13 species known to live around or regularly visit our coasts.

The National Whale and Dolphin Watch, sponsored by BG, is now in its eighth year. As well as taking part in National Whale and Dolphin Watch, members of the public can support the work for Sea Watch through its adopt a dolphin campaign. See www.adoptadolphin.org.uk