Anxious rangers on the remote Northumberland Farne Islands had feared that its puffin numbers were in decline after noticing fewer seabirds nesting last May.
However, it now seems the low count was actually due to the thriving grey seal population who had inadvertently crushed puffin burrows on the outer islands, meaning more birds were nesting on the inner isles.
Fears were further alleviated when results of a five-yearly survey, completed by the National Trust who cares for the island, revealed that puffin numbers are stable. Burrows on eight of the 28 island archipelago were checked during the survey and showed puffin numbers at around 44,000 pairs, nine percent higher since the last count in 2013.
National Trust ranger, Thomas Hendry says: “When we started the count in the outer group of islands we were very anxious that numbers were down, especially as we know puffins are struggling for survival across the globe.
“After further investigations on the inner group of islands, numbers seemed to be much more positive. This could be due to the islands being more sheltered, providing an ideal habitat for the puffins to successfully breed and raise their young.
“Another factor for the lower bird numbers on the outer islands could be the success of our grey seal population. We have seen seal pup numbers growing from 1,704 to 2,602 in the last five years.
“A rather unfortunate consequence of this growth is the seals are competing with puffins for areas to raise their young. Although the two species are in residence and breed at different times of year, the weight of the seals could be crushing the puffin burrows and eroding surrounding vegetation.”
The Atlantic puffin was classified as vulnerable in 2015 by the International Union for the Conservation of Nature (IUCN) after worldwide numbers dropped. The most likely reasons for this decline include climate change contributing to food shortages and extreme weather, overfishing, invasive predators such as rats on some islands and marine pollution.
Puffins have traditionally done well on the Farnes thanks to the work of the National Trust rangers, increasing protection of the marine areas around the islands, a lack of ground predators and the availability of suitable nesting areas.
For more information about the Farnes visit www.nationaltrust.org.uk/farne-islands.
Image: Atlantic Puffin, Paul Kingston ©National Trust