Puffins suffer as warming sea hits food supply for nesting isle

Published on 03/06/2008 22:50

PUFFIN numbers on one of Scotland's strongholds have dropped by 30 per cent in five years.

It is believed Scotland's most popular seabird could be suffering because of a lack of food supply caused by warming seas as a result of climate change.

The Isle of May in the Firth of Forth is home to the largest colony of puffins in the North Sea.

After almost 40 years of numbers rapidly increasing on the island, the puffin population has now dramatically fallen.

Five years ago there were 69,000 pairs of puffins on the Isle of May but now numbers have dropped to just 41,000 pairs.

This contrasts to 100,000 pairs that scientists had expected to find if numbers had continued growing at previous rates.

Professor Mike Harris from the Centre for Ecology and Hydrology, who led the research, has been studying puffins on the Isle of May for the past three decades. He said: "Something worrying appears to have happened over last winter and probably the one before.

"Puffins appear to be joining the ranks of other seabirds in the North Sea that are suffering reduced breeding success and decline in numbers."

He thinks the most likely cause is sea warming, which has an impact on the amount of plankton in the water.

With fewer plankton the fish that feed on them are affected, and so are the puffins that rely on the fish to feed.

"Puffins can probably cope quite well with a change of sea temperature," he said. "It doesn't affect them directly but just through the food supply."

He said when the birds returned to the Isle of May this year to breed they were very underweight compared to normal, backing up the theory they are struggling to find enough food.

"It's too early to start talking about the demise of the puffins but we need to understand what's going on," he said.

He said another possibility is that large numbers decided to have a year off from breeding. But this is very unlikely.

"We also need to widen the survey to include other colonies in the North Sea to measure to what extent the population is declining in the area," he said.

Caroline Warburton, manager of Wild Scotland, said it was worrying, as puffins were a huge tourist attraction. "They are by far the favourite seabird. If they suffer a similar drop over the next few years, it would become much rarer to see puffins."