Icelandic puffins have laid noticeably fewer eggs in the Westman Islands and Breiðafjörður this year. This was among the findings in the annual Icelandic Atlantic Puffin Monitoring Program report produced by the Westman Islands’ South Iceland Nature Research Centre (NS). NS surveyed twelve puffin nesting sites around Iceland.
The bay of Breiðafjörður in West Iceland and the Westman Island archipelago off the south coast are extremely important breeding grounds for puffins in Iceland. Indeed, 60% of the country’s puffin population lay their eggs one of these two grounds.
There are about half a million puffin burrows in Breiðafjörður. Each puffin burrow can accommodate two puffins (one breeding pair), but the usage of these burrows varies from year to year. According to NS director Erpur Snær Hansen, last year—a particularly good year where puffin breeding is concerned—puffins laid eggs in 88% of the Breiðafjörður burrows. This year, by contrast, only half the burrows are in use. This is a nearly 34% decrease in burrow usage. The Westman Islands boasts more than double the number of puffin burrows, that is, over a million. Last year, 78% of the burrows in the Westmans had eggs in them; this year, only half do.
Erpur attributes the decline in breeding in both of these areas to localized changes in puffins’ food sources.
All but one of the other puffin breeding grounds surveyed had little to no variation in burrow usage since last year. And there is some good news: Lundey island in Skjálfandi Bay in North Iceland has seen a 13% increase in burrow usage this year.
Erpur says that puffins started laying eggs earlier than usual in the Westmans. In fact, he came across two pufflings during his survey of the islands’ nesting grounds. If they mature at the normal rate, these pufflings will leave the nest in early August. “That’s three weeks earlier than it has been for the last ten years or so,” said Erpur.
Iceland’s puffin stock has been declining in recent years and is having difficulty rebounding, despite good breeding seasons like last year. The puffin, along with the Eurasian curlew and the great skua, is currently listed as a “critically endangered” species on the Icelandic Institute of Natural History’s Red List for Birds.
NS will be surveying puffin breeding grounds again in July to find out how many pufflings have hatched and how they are faring.