Global warming exiles native species

As temperatures rise, many familiar plants and birds are disappearing. Meanwhile, Britain is becoming home to exotic newcomers from southern Europe.

The map of Britain's countryside and wildlife is being steadily redrawn by climate change, and it may already be too late to reverse many of the alterations to the habits of flora and fauna, the Government has admitted.

The map of Britain's countryside and wildlife is being steadily redrawn by climate change, and it may already be too late to reverse many of the alterations to the habits of flora and fauna, the Government has admitted.

Within a few years, southern England will be home to creatures more familiar to the Camargue while, in the longer term, the traditional plants of the Midlands will retreat as far north as the Grampians if they are to survive.

The alarming change is acknowledged in The Rural White Paper, a consultation document, due to be published at the end of the month, which outlines Government policy and guidance on countryside and environmental issues.

Some flowers, birds and animals will flourish as the temperature warms up, enabling them to colonise northern areas of Britain. But others, for whom most of Britain is already too warm, will leave our shores altogether. Wildlife from the continent is already making the leap across the channel to southern England.

The White Paper acknowledges that "the likelihood of climate change will force species to migrate northwards or to higher ground, whilst low-lying coasts will be flooded and wetlands will become drier". On the last page of the 30-page document is a small paragraph providing an illustration - the loss, due in part to rising sea levels, of 60 per cent of salt marsh and 90 per cent of coastal grazing marsh in the Essex estuaries.

The report recognises that "it will not be feasible to keep every species where it is now or every habitat in the same condition", and that there will be little point in protecting some species.

The speed of change will vary. Many alterations to our countryside will be subtle and take decades, if not centuries. But others are already happening, with exotic birds, usually seen occasionally, now becoming more permanent.

The little egret, which is common on continental Europe but unknown in the UK just five years ago, now numbers several hundred breeding pairs in the estuaries of southern England. It is expected to be followed shortly by the cattle egret, a bird normally associated with southern Spain and the Camargue in France, and two other continentals: the fan-tailed warbler and the serin, a tiny, olive-green finch.

The bittern, a dumpy-looking heron that is widespread elsewhere in Europe, has now been sighted in Wales.

According to the Wildlife Trusts, the winners will include the Dartford warbler, locally endangered in Britain, but which is expected to extend its range as the climate warms up, along with the hobby and the Cetti's warbler, which already has a stronghold in Northamptonshire. The melodious song of the nightingale is expected to be heard soon well beyond its traditional southern habitat. The little stint, black-tailed godwit and the ruff - birds that normally migrate in winter - now find it warm enough to remain. Warmer seas are also attracting greater numbers of turtles and trigger fish, a small burrowing creature. Salmon, on the other hand, may suffer adversely, with rising water temperatures creating algal blooms that may deprive them of oxygen.

Our shores may soon be too warm for others, such as the snow bunting and ptarmigan, which breed in northern Scotland, while warmer weather on the continent means that swans and geese are becoming an increasingly rare sight in the UK. "There's no need for them to make that extra journey south when the climate is warm enough for them in northern Europe," said Tim Appleton, of the Leicestershire and Rutland Wildlife Trust and reserve manager at Rutland Water.

He added: "It probably doesn't matter if one species moves away. It's the overall impact of things happening in such a short time. Nature needs a long time to adapt."

The picture is also mixed for plants, which take longer to migrate. "Many plants that are on the southern limit of their range in Britain are going to be quite threatened," said Jenny Duckworth, conservation officer for Plantlife, the environmental organisation. "The same applies to species on top of mountains which will simply not be able to go any higher."

One flower that may disappear altogether from the UK is the Baltic bogmoss, found in one location in Northumberland and in Abernethey forest near Aviemore. Another extremely rare flower is the Snowdon lily, localised to Snowdonia in North Wales, while the tufted saxifrage, found on sheltered mountain ledges in northern Scotland and Wales, may be squeezed out, unable to find a suitably cold climate.

However, the lizard orchid, which carries a characteristic "goat's smell" and is extremely rare in Britain today, is soon expected to become as common as it is in Brittany and southern France.

The difficulties for flowers and plants is that habitats in Britain are fragmented: not only do conurbations place obstacles in the path of migration, but many areas, while recognisably the "countryside", may no longer be suitable: chemical fertilisers used in farming have left swathes of land rich in nitrogen and hostile to the majority of wild flowers.

Some species in southern England may struggle to move farther north from the chalk and limestones that provide their natural habitat. The stemless thistle, common on chalk downlands in southern and midland Britain, may well need to move farther north to avoid warmer weather - but could face problems finding suitable habitat.

In order to survive, plants will have to move 10 times more quickly than they did at the end of the last Ice Age. "Even the plants that may benefit will face problems," said Dr Duckworth. "During the last Ice Age, species were able to keep up with the climate, but the predicted rate of temperature changes is much greater, so the concern is that some species won't be able to keep up and adapt quickly enough to survive."