While the mass deaths of seabirds – known as “wrecks” – are not uncommon, they are very unusual at this time of year, tending to happen after bad storms in the winter.
Francis Daunt of The UK Centre for Ecology and Hydrology (CEH) said hundreds of birds had been found dead or starving along the Northumberland and Scottish coast, and warned that the “razorbill/guillemot event” was moving further south.
Dr Daunt said many of the birds appeared “emaciated”, and less than half their usual weight, which he described as “catastrophically low”.
The CEH has ruled out bird flu after testing, but said another cause could be poisoning from algal blooms.
Birdwatchers following their progress said many of the birds appeared “listless” and “a bit dopey” and were taking no evasive action when boats approached.
Conservationists in Northumberland said razorbills and guillemots from the Farne Islands should usually be getting ready to go out to sea for the winter and suggested they may have moulted late, meaning they cannot yet fly.
Although a recent spate of northerly winds may have disturbed feeding grounds, experts said that it had settled down, so there seemed little reason for the birds to be avoiding heading further out to sea.
Plenty of eels to eat
There also appear to be rough sand eels for populations to eat, so conservationists are confused as to why so many appear to have starved to death.
Tom Cadwallender, a freelance ornithologist who formerly worked for the Northumberland Coast Area of Outstanding Natural Beauty (AONB), told the Northumberland Gazette: “I’ve been birdwatching on the Northumberland coast for 50 years and this is unprecedented.
“Hopefully we will find out soon what is happening but it is quite alarming.”
Seabirds were thought to have had a good breeding season this year, particularly in areas such as the Farne Islands, off the Northumberland coast.
Members of the public have been warned not to touch the birds without gloves if they find them washed up in case they are carrying an infection.
David Steel of the Isle of May Nature Reserve said: “The scale of the event appears to cover a vast area of the east coast but please remember if you do find any dead birds, please wear gloves before handling.”
