'Tropical' dolphins strand on Irish coast - another consequence of global warming ? [9/11/00]

The Striped dolphin is a tropical, warm water species common in the Mediterranean Sea.  It was first recorded in Ireland in 1985 but has been recorded with increasing frequency throughout the 1990s. 

Yet another Striped dolphin was found washed up on Sunday - the fifth individual of this species recorded during the last 6 weeks and for the second year running Striped dolphins are the third most frequently stranded cetacean (whale, dolphin and porpoise) species in Ireland.

The rapid increase in occurrence of this species of dolphin strongly suggest that the seas around Ireland are warming quickly enough to apparently change the distribution of marine top predators such as dolphins.  If the effects of climate change are affecting the marine environment so markedly perhaps the recent floods and gale force winds are a sign of future weather patterns ?

The Irish Whale and Dolphin Group have been co-ordinating a stranding and sighting scheme around the whole island of Ireland since 1991.  A recent review of stranding records (Berrow, S.D. & Rogan, E. (1997) Cetaceans stranded on the Irish coast, 1901-1995.  Mammal Review 27(1), 51-76.) suggests they are only suitable for identifying unusual events such as epizootics or interactions such as fishing mortality.  The increase in Striped dolphins on the Irish coast is so dramatic that the stranding records clearly show this change in distribution.

Recent Striped dolphin Strandings:

5 November, Ballyferriter, Co. Kerry
24 September Ballyferriter, Co. Kerry
18 September Westport, Co. Mayo
17 September, Rossbeigh, Co. Kerry
15 September Inishboffin, Co. Donegal