Scientists from the Wildfowl & Wetlands Trust (WWT) fear that hungry polar bears are jeopardising a conservation success story by feasting on the eggs of barnacle geese because melting Arctic ice is making seal hunting too difficult.

According to research by WWT and a Dutch university, this year saw only half of the expected numbers of barnacle goslings overwintering on the Solway Firth where successful efforts to rebuild the flocks have created a major tourist attraction.

Polar bears are the prime suspects because more and more are gathering around the islands off Spitsbergen where the birds go to breed each summer, and researchers have photographed the polar bears in nests and are finding regular evidence of wrecked nests and egg debris.

Brian Morrell, a zoologist based at WWT Caerlaverock, Britain’s premier barnacle goose reserve, says: “Our suspicion is that, as climate change reduces the polar ice-floe, making it harder for the bears to hunt for their usual diet of seal, they are being driven by hunger to prey on nest sites.

“Obviously, it takes a very large quantity of eggs to satisfy an animal as big as a polar bear, especially one with cubs.

It is a tragedy to witness two species of conservation concern clashing over the right to survive, and demonstrates very graphically the tensions the natural world is experiencing now.

“The impact is that entire nesting areas are being stripped bare of eggs and young, with potentially dire consequences for the geese, a stunning wildlife spectacle and wildlife tourism.”

WWT’s chief executive, Martin Spray, added: “It is a tragedy to witness two species of conservation concern clashing over the right to survive, and demonstrates very graphically the tensions the natural world is experiencing now.

“The situation is made all the more sad for WWT and its international partners because the barnacle goose’s revival has been a conservation success story of which we were immensely proud.

“In the 1940s, numbers had slumped below 300; today, up to 30,000 birds at a time can be seen from WWT Caerlaverock – to the delight of locals and visitors and to the benefit of the tourist economy.”

Brian Morrell is returning to Spitsbergen, off Norway, this summer to monitor how many eggs and chicks are being lost to polar bears and to assess if enough barnacle geese can find higher nesting sites, to escape polar bear predation.

He explains: “Barnacle geese are very long-lived; we have records of some reaching 25 or older. They could have time, then, to recover from one or two seasons of limited breeding success, perhaps by switching to a cliff nest site.”

But, he continues: “Inland cliff sites are in short supply and it isn’t only the bears which are attacking nests. By frightening away the adults, the bears are also laying nests open to attack by other predators, including gulls and skuas. There’s no doubt the habitat is under pressure and that it is tricky to know how to resolve it without risk to one or both species.”

Photo credits: Brian Morrell and Jouke Prop