The Independent makes an unsourced claim that there is only a single Lady Amherst's Pheasant (Chrysolophus amherstiae) left in the wild in Britain. If so, doubtless the species is functionally extinct in this country.

The bird, common and widespread in south western China and Myanmar, is named after Sarah, Countess Amherst, wife of William Pitt Amherst, Governor General of Bengal, who was responsible for sending the first specimen of the bird to London in 1828. Since then these spectacular creatures have been breeding quietly in the Home Counties and Eastern England, never very numerous nor much trouble.

So, should we be worried? The Independent querulously notes:

Unless it can find a previously unsighted mate, and breeds successfully, Lady Amherst's will become the first bird species since the great auk to be lost from the British countryside.

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This is undoubtedly true, leaving aside the crucial distinction that the Great Auk was a native bird and the Lady Amherst's is not. Lady Amherst's is an introduced species which established a feral population. Given its relatively recent introduction and small numbers, it is unlikely that any other species depends upon it, and so its loss will probably pass unmarked by humankind or any other creatures. The reason for its decline is not known - the Indy predictably suggests foxes as one possible agent - but really most people asked to come up with a wild guess might have done no worse. The truth is we don't know, and we won't know. With only one bird left, it will be impossible to go back and see what happened to the others. We can note the disappearance of a rarely-seen but truly spectacular bird, but it would be inappropriate to draw any wider conclusions from it.