Why is it so hard to identify a swan?

WHO, WHAT, WHY?
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In depth: Bird flu

It's 12 days since a swan with the bird flu virus was found in Fife and scientists have only just identified what species it is. Why did it take so long?

It sounds like one of the easier tasks for government scientists - identifying what species the headless swan with the H5N1 bird flu strain is.

But 12 days after it was found near Cellardyke harbour in Fife, DNA tests have only just identified it as a whooper swan and scientists are being criticised for the length of time the tests took.

Finding out is crucial in helping epidemiologists understand how the virus got to the UK, how it was transmitted and what the consequences are.

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Being a native bird it could only have caught flu from another bird flying to Britain, possibly a summer migrant arriving any time in the past few weeks. As a result the virus could have been spreading through Britain's bird populations for some time.

If it had been a migratory species there would be more chance that Britain could escaped a serious outbreak. An infected migrant could have flown across the North Sea and then collapsed and died before being washed ashore.

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According to Defra, the job proved so difficult because the bird was so badly decomposed.

"The bird was found in an advanced state of decay, with its head missing, making it hard to identify," says a spokesman.

THE UK'S SWANS Left: Mute swan Middle: Whooper Right: Bewick's

The Royal Society for the Protection of Birds (RSPB) says the length of time taken to identify it was not ideal, but the task was not as simple as it sounds.

"Swans are usually identified from their heads, but this bird was headless," says a spokesman. "It was also very discoloured and decomposed, making the task far more complicated. It's not as simple as looking in a book.

"Making sure the bird is properly identified is a crucial part of assembling the jigsaw that is bird flu. Poor attempts in other parts of the world have severely hampered investigations.

"There is the expectation that the UK Government would be able to identify for certain any bird found with bird flu in this country. I can't emphasis enough how important it is that they get it right."

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People are so accustomed to the 24/7 news-on-feed approach that they expect everything yesterday. I'd rather have the real facts than some early knee jerk reactions or assumptions. Lets avoid mass hysteria for once and approach things in a considered way ... both scientifically and in the press. On the question of identification... aren't there some genetic identifiers?
Sarah Beal, Cardiff

I agree, this delay is not acceptable, the government labs must have identified the strain after 11 days. What will happen (more infections will undealted be reported)when they get more reports. Also, the slaughter of chickens, I hope will not follow the course of the BSE for cattle. Lets be truthful, that mass killing was just unecessary slaughter.
johnlaybourne, luton

Why is it assumed that a wild migratory bird was in any way responsible for this case? It seems more likely based on past experience that the virus in this bird got there because of direct or indirect exposure to domestic poultry or waterfowl in Britain. If, as seems likely, this was a feral Mute Swan, then the most likely scenario is that it got the virus from a poultry farm. Wild migratory birds are being made the scapegoats for the excesses of industrial agriculture.
Dr Ian L Jones, St. John's, Newfoundland, Canada

surely the question is "Where is the head?" If it's head is missing, can we not assume some animal ate it? As the swan is infected, if it was another bird, it is likely to have caught the desease. So, is the key not to find the head?
David P, Uxbridge, England.

"DNA tests are now being carried out to provide a positive identification" could these not have been done to begin with!
Sarah, Fife

The solution seems obvious and we already have a precedent - introduce a law to make all swans carry identity cards.
ChrisR, Derby

Identity cards for swans is a stupid idea - swans don't have pockets. Tagging and curfews -that's what we need.
Cat, London, UK

So scientists cannot identify the species of a headless swan. Does this mean they're running around like headless chickens?
Graeme, Dundee, Scotland

The important question is, does it still count as property of the Queen?
Matt, London

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