Hurricanes and global warming bring unusual visitors as digital cameras and social networking encourage new enthusiasts
Sunday 30 October 2011
A Siberian rubythroat. Photograph: David Tipling/Alamy
Birds winging their way to their breeding grounds on the other side of the
Atlantic or in the Pacific have been left stranded in and Britain , adding their numbers to native species. Ireland
Twitchers, as the most fanatical birdwatching enthusiasts are termed, have already observed a total of 442 species in the
British Isles this year. The highest number ever spotted in one year is 445, in 2008.
"We only need three more and we will have equalled our record – and given that November is often the best month of the year for spotting rare birds here, I'm very confident we are going to see the record broken before the end of the year," said Lee Evans, who runs the British Birding Association.
Last month a Siberian rubythroat – a tiny brown bird with a scarlet chest – was spotted outside Lerwick in Shetland. A native of east Asia, it is extremely rare in
, but has now spent the past two weeks at the very northern edge of the nation, caught by the cameras of twitchers who have flocked to the island. Britain
Similarly, a bufflehead – a small duck with a distinctive bulbous head – was spotted in a farm pond on the Lizard in
. "It was absolutely knackered when it arrived," said Evans. "It had been migrating south from Cornwall to southern Canada when it was swept out into the United States Atlantic by a storm. It had probably travelled more than 3,000 miles, which explains why it was knackered." The bufflehead has since flown on, probably to , he added. Portugal
Evans said that global warming over the past decade was playing a key role in transforming bird movements across the globe. Climate changewas transforming weather patterns, causing a dramatic rise in hurricanes and storms, particularly over the
Atlantic. "In the 1990s the average total for numbers of bird species spotted every year was 412," he added. "Now that figure is around 440. That is a very significant change and global warming lies at the root of it."
In addition, melting Arctic sea ice may be involved. Ornithologists have suggested that the disappearance of ice cover is opening up migration routes over the north pole, making it easier for birds from the Pacific to reach
– such as the slaty-backed gull, a native of the north Pacific, which appeared in the Britain Thames estuary on the Rainham landfill site this year.
The expectation that 2011 would be a record year for bird species numbers in the
British Isles was backed by Grahame Madge of the RSPB: "There are different ways to count species, but I think whatever system is used we should expect that records will be broken this year.
"Climate change is certainly implicated, but there are other factors. Access to the internet and improvements in digital cameras are also involved. A tufted puffin from the north Pacific, a medium-sized black seabird with distinctive white facial markings, was recently seen in the
, though only a handful of spotters were involved and they only got a brief glimpse. Crucially, however, one of them was able to take a few photos. He posted these on the internet where they were confirmed as being images of a tufted puffin. That kind of technology makes it possible to pinpoint more and more species," he said. UK
In addition, birdwatching is becoming an increasingly popular hobby among all age groups, added Madge. "A fifth of RSPB members are under the age of 18. This is a round-the-year hobby that you can enjoy from the kitchen window or from a car. More and more people are birdwatching, and as a result more and more unexpected species are being spotted in the
As to the species that have yet to appear but which could do so in the next few weeks, turning 2011 into a record year of activity for twitchers, there are three likely candidates, added Evans. "There is the eyebrowed thrush, from
Siberia, the American purple gallinule, from the southern states of the , and the black-throated thrush, also from US Siberia. They have all been seen over here before, but we haven't had a sighting of any of them so far this year."
The jump in bird species numbers in the
British Isles is good news for twitchers, who obsessively follow news of sightings in order to add rare species to their lists – though the increase does pose financial problems for the birdwatching community. "It is an incredibly expensive hobby to keep up," said Evans. "Most of the rare visitors arrive in the Scillies, the Outer Hebrides, Orkney or Shetland – all at the fringes of the British Isles. Flights can cost £600 to get there.
"The alternative is to drive, then take the ferry. Every year I run up about 70,000 miles on my car doing this. That means spending thousands of pounds just on petrol. Essentially, I go through a car a year to spot these birds. And now we are getting more and more of them."
Siberian rubythroat (Luscinia calliope)
A member of the thrush family which is distinguished by its olive-brown upper parts, bright red throat and white stripes above and below the eyes. It is a migratory, insectivorous species, breeding mainly in forests in Siberia. The rubythroat winters in India and Indonesia and is normally rare in western Europe.
Northern waterthrush (Parkesia noveboracensis)
A migratory bird, found predominantly in
North America, with a throat lightly streaked brown to black. The species winters in Central America, including the West Indies, , Florida and Colombia . Waterthrushes are terrestrial feeders with a diet consisting mainly of insects, molluscs and crustaceans. Ecuador
American purple gallinule (Porphyrio martinica)
A medium-sized bird with purple-blue plumage, it inhabits swamps, lagoons, flooded fields and ponds. Breeding takes place in the southern states of the
. Purple gallinules are omnivores feeding on anything they come across: vegetables, animal matter, fruit and all types of seeds. United States
Bufflehead (Bucephala albeola)
The bufflehead is a small diving duck that forages underwater, eating primarily aquatic plants and fish eggs. Adult males are black and white with iridescent green and purple heads. Females are a grey tone with light undersides and similar white behind the eye. The term bufflehead refers to the bird's strangely bulbous head shape. They are migratory birds, wintering in the northern and southern US.
Slaty-backed gull (Larus schistisagus)
Also known as the Pacific gull, the slaty-backed is grey-black in colour with dark upper wings and is a coastal species of northern
Asia and the Bering Sea. The bird breeds on the western coast of . Like most gulls, it is a scavenger. Alaska