Winter Waterfowl

(This was first published in issue 69 of The Review)
Valerie Selby, Wandsworths Principal Parks Officer (Biodiversity) writes:
Those of you who regularly walk around the lake within the park will perhaps notice that you see different birds through the year. Many species of waterfow (ducks, geese and swans) undertake an annual migration to spend the winter here in comparatively warmer weather and where food is plentiful, at a time when their breeding grounds such as Iceland and Eastern Europe get much colder and food becomes scarce. The UK’s wetlands overall support internationally important numbers of these wintering waterfowl. Overall Battersea Park has 9 species that are more numerous in winter but which can be seen all year round in ones or twos. These are:

The Wetland Bird Survey (WeBS) is a scheme, run by all the main bird organizations, which has monitored non-breeding waterbirds in the UK at some sites since 1947. The principal aims of WeBS are to identify population sizes, determine trends in numbers and national distribution and to identify important sites for waterbirds. Battersea Park is a site at which WeBS counts take place; volunteers participate in monthly counts, mainly during the winter. The data will enable us to pinpoint the importance of Battersea Park for waterfowl within the London context. It may also be able to show us whether the birds really are getting to us later each year – much anecdotal evidence would suggest this is the case. If birds are coming to us later and indeed staying late into the spring or leaving earlier, this may be linked to climate change. Potentially, if countries such as Iceland are getting warmer, even by a degree or so, it would mean that the available food is around for longer and so the trigger to start the migration may not come into play until later in the year. Currently, there is obviously a lot of concern about the potential for wild (migratory) birds to be the first vector for bird flu into the UK. DEFRA are working with RSPB, BTO, WWT, and BASC to monitor water birds, particularly along migratory flyways, for the infection.
So far (early March) they have taken over 3500 samples from wild birds, and have not detected H5N1 in the UK. If you see a dead water bird (duck, goose, swan, heron) in the lake in Battersea Park and are concerned, please contact Valerie Selby (Principle Parks Officer for Biodiversity) as soon as possible on 020 8871 7019. She will need a time and a precise location in order for the information to be useful. It must be remembered however that at this time of the year quite a few young birds die of natural causes so seeing a dead water bird should not cause instant panic!