Last modified: 22 February 2010
Image: Chris Gomersall
Each winter Britain sees the arrival of millions of waterbirds of many different species from the Arctic and northern Europe.
Chichester Harbour is one of the prime destinations for these birds. It is listed as a principle site for waterbirds in the UK with three species occurring in internationally important numbers. These are: dunlin, black-tailed godwit and dark bellied brent goose.
In the last five years Chichester Harbour supported an average of 46, 588 birds and neighbouring Pagham Harbour supported 19,387.
An analysis of the 50 most widespread winter-visiting wetland birds (excluding gulls) shows there have been some very dramatic changes over the last decade.
The five birds faring the worst, compared with a decade ago, include: ringed plover; pochard; bar-tailed godwit; and the Greenland white-fronted goose. While the five recording the greatest increases over the period include: little egret; whooper swan; black-tailed godwit; avocet and the Greenland barnacle goose.
Dr Mark Avery, the RSPB’s conservation director, said: “Two aspects of this long-running study really stand out. Firstly, that bird populations change over time and understanding this is critical to developing future conservation strategies.
“Secondly, that the UK's wetlands, and particularly those on the coast, are of enormous importance to the survival of a great number of waterbirds which migrate from many other countries. The protection and wise management of our wetlands is a priority to ensure that they continue to provide a lifeline to bird populations in the face of climate change.”
For some declining species, such as the ringed plover and bar-tailed godwit, it seems they are shifting away from wintering in the UK, preferring to spend the winter in continental Europe.
However, those species which have increased in number are increasing for a variety of reasons. Avocets are believed to have increased because of milder winters and targeted conservation action, while the black-tailed godwit and whooper swan, which migrate from Iceland, are thought to be increasing because of subtle changes in farming there, possibly linked to climate change.
The annual report is based on the fieldwork of around 3000 bird surveyors participating in synchronized monthly counts at wetlands, including estuaries, marshes, lakes and reservoirs, across the UK.