Super-sized mice on an island in the South Atlantic are eating seabird chicks alive, according to alarmed wildlife watchers.
The mice, three times the size of those normally found in Europe, attack at night and are devouring more than one million petrel, shearwater and albatross chicks on Gough Island every year.
The island, a World Heritage site in the South Atlantic, is the most important seabird colony in the world, hosting more than 10-million birds. It is one of the Tristan da Cunha group of islands — a British Overseas Territory.
Dr Geoff Hilton, a senior research biologist said, ”Gough Island hosts an astonishing community of seabirds and the catastrophe could make many extinct within decades.
”We think there are about 700 000 mice, which have somehow learned to eat chicks live, much like blue tits learned to peck milk bottle tops.
”The albatross chicks weigh up to ten kilos and ironically albatrosses evolved to nest on Gough because it had no mammal predators — that is why they are so vulnerable. The mice weigh just 35 grams, it is like a tabby cat attacking a hippopotamus.”
Gough Island is the most southerly of the Tristan da Cunha group. There are 22 bird species nesting on the island of which 20 are seabirds.
The island hosts 99% of the world’s Tristan albatross and Atlantic petrel populations — the birds most often attacked.
Just two thousand Tristan albatross pairs remain.
The predatory behaviour of the mice was suspected then confirmed by Dr Richard Cuthbert and Ross Wanless, a PhD student from the University of Cape Town’s Percy FitzPatrick Institute. Ross Wanless recorded dramatic video footage of the attacks last year.
Cuthbert said, ”The albatross chicks spend eight months sitting waiting for food from their parents.”
”They are nearly a metre tall and 250 times the weight of the mice but are largely immobile and cannot defend themselves.
”Without predators this would not be a problem, but for a carnivorous mouse population on one of the wettest and windiest places on earth, it is an easy meal of almost unimaginable quality. The result is carnage.”
Ross Wanless said, ”There are mice on other South Atlantic islands but Gough is the only site where this is known to be happening.
”Once one mouse has attacked a chick, the blood seems to attract others. They gnaw into the chick’s body, create a gaping wound and the chick weakens then dies over several days.”
Scientists suspect that the mice are also eating the eggs and chicks of the rare, ground nesting Gough bunting, a small finch found no-where else in the world. Researchers think the finch has been forced from the best nesting sites into less suitable uplands areas.
”This species is one of the most worrying because there is no other population in the world,” said Hilton. – Sapa-DPA