Surfbirds News: July 2007 Archives
Norman Ratcliffe, seabird ecologist with RSPB Scotland, said: 'Yet again, Scotland's seabirds seem to have had another worrying season. Our reserves on Orkney and the west coast definitely seem to have suffered from lack of food to feed chicks.
'Some cliffs - which should be packed with birds - are just about bare, as adult birds abandon the nest once their breeding attempt has failed.
'This is all linked to food availability, which can be disrupted for a number of reasons. We're fairly certain that on the east coast, rising sea temperatures are leading to plankton regime shifts, which in turn affects fish like sandeels - a major food source for seabirds.
Puffin, Northumberland, copyright Sean Gray
'Sandeels might be abundant for a time, but when this critical food source enters the next phase of its life cycle, they swim down to the bottom of the sea and bury themselves in the sand, meaning they become unavailable as food.
'This often happens sometime in July, but if it occurs early, you can get mass mortality of near-fledged chicks as has been seen for terns nesting on Coquet Island, in Northumberland, this year.
'Parent birds may then switch to pipefish, but chicks find these hard to swallow, they are less nutritious, and the parents spend much longer away from the nest, leaving chicks vulnerable to predation and attack from neighbouring nests.'
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