Birdwatch

Geese in the UK can be broadly split into two groups: the anser geese, otherwise known as 'grey geese', which include the greylags, white-fronts and pink-feet, and the branta geese, which are the Canadas, brents and barnacles.

At Pulborough, we have had a small group of white-fronted geese Anser albifrons (11 to be precise), while others have appeared in the Cuckmere valley and elsewhere.

There is normally a large flock of white-fronts that winter in the Rye Harbour-Dungeness area of the East Sussex-Kent border but few venture much further west in Sussex.

In recent days, there has also been a larger number of barnacle geese appearing than normal, plus a few bean geese, and there was a solitary pink-footed goose in the Arun valley too.

Where these geese have come from is unclear. First the barnacles. Like the familiar Canada geese, there is an established feral population in the UK that breed in small numbers and inhabit all kinds of artificial wetlands such as gravel pits and reservoirs in different parts of the country.

A large population of 'wild' barnacle geese winter on the western isles of Scotland (particularly Islay) and around the Solway Firth. These birds breed in Greenland and Svalbard respectively.

A different population of barnacles, breeding in Arctic Russia and north-east Europe, winter mainly in the Netherlands.

It is possible that the birds we have seen in Sussex recently are from just the other side of the North Sea but it is also possible that they are feral UK birds that have been moved from their usual haunts by the cold weather.

Just as there are distinct populations of barnacles wintering in different parts of the country, there are two populations of white-fronted geese that are separated geographically.

White-fronted geese that winter in the south of England breed in Arctic Russia (known as albifrons) and are part of a widespread and numerous population that migrate to many different locations throughout Europe.

Greenland-breeding white-fronts (known as flavirostris) winter largely in south-west Scotland and are a very rare bird indeed in global terms.

Barnacle geese are beautiful grey-bodied, white-faced and black-necked birds, smaller than Canada geese and rather kinder on the ear. Because of the similar colour combination of Canada geese, the occasional barnacle goose can easily disappear in a large flock of Canadas.

White-fronted geese are a little smaller than the greylag and have a striking white patch surrounding the bill on the front of the head, which is often visible at great distance. They also have variable amounts of black or dark brown markings on their bellies, as though they have been walking through wet grass or mud.

Here at Pulborough we rarely see more than about 20 birds every winter, and they often associate with flocks of the much more common greylag geese.

It is worth looking through the flocks just to check!

This first appeared in the West Sussex Gazette February 27. To see it first, buy the West Sussex Gazette every Wednesday.