SCIENTISTS last week warned of a new strain of bird virus which targets great tits spreading north through Britain.
The new strain of avian pox, which causes warty, tumour-like growths particularly around the eyes and beak, has not yet been seen in the Borders.
Oxford University’s Dr Shelly Lachish said: “Although recovery from infection can occur, our results show that this new strain of avian poxvirus significantly reduces the survival of wild great tits and has particularly large effects on the survival of juvenile birds.”
The growths can stop the birds from eating and increase their susceptibility to predation.
Scientists say the virus is unlikely to have originated in Britain and more probably occurred through the arrival of an infected mosquito. And the RSPB and Zoological Society of London experts have tracked the disease from south-east England to central England and into Wales over the last five years.
Borders RSPB officer Mike Fraser said: “These things have the potential to spread countrywide and there is nothing to stop it getting up here. It will work its way through the population and the birds that survive will be the fittest.”
Of greater immediate concern, as Borders bird lovers gear up to feed feathered friends over the winter, is the known disease paratie trichomonosis.
“Birds foam at the beak and get fluffed up even though it may not be cold, and the disease is fatal which is why it is so important to keep bird feeders and baths clean. It’s like your own kitchen, it’s the same for the birds,” said Mr Fraser.
He advised those wanting to help to feed birds appropriate food regularly and keep feeders, bird tables and bird baths washed and disinfected every week. Commercial bird food is best, but kitchen scraps such as brown bread and cooked rice could be given – as long as any uneaten scraps were cleared away – and apples stored now could be fed after current fruit and berries are used up.
He continued: “Likewise, many birds that might benefit from the food are actually put at risk from diseases and parasites that accumulate at feeding sites and can be transferred between the birds as they visit the feeding sites. If you can, move your feeding stations around the garden so that there isn’t a build-up of uneaten food on the ground beneath them.”
The poor spring and summer have not been all bad news as the wet weather made worms easier to find for some birds, he told us.
“The results of the various national nesting success and breeding bird surveys are not yet fully in for this year, but it would be fair to say that a number of species have suffered as a result of the horribly wet weather in spring and summer,” said Mr Fraser.
“Ground-nesting species such as Lapwing are likely to have fared badly as their fluffy chicks become wet and chilled. Some garden birds might have done quite well, as the wet weather might have made it easy to find worms to feed the chicks.
“Others, such as insect-eating warblers, are likely to have suffered.”
But feeding birds in your garden does make a difference.
“The level of use by birds of gardens was brought home to me in late April,” said Mr Fraser.
“I’m a licensed bird ringer, and on one day in my Selkirk garden I caught 228 Siskins.
“Some of these might have been continental or Scandinavian birds moving through; others were probably local – it’s a common bird in conifer plantations in the Borders.
“One that I ringed was found a few weeks later in Innerleithen; another had already been ringed at Lockerbie earlier in the year.”
Sightings of birds with avian pox should be reported to the RSPB on 01767 693690 or online via: www.rspb.org.uk/advice/helpingbirds/health/sickbirds/avianpox.aspx.