What's that on my bird table?

The cold weather is bringing all sorts of unusual birds like this reed bunting into UK gardens, according to the RSPB Photograph: Roger Wilmshurst/Frank Lane Picture Agency/Corbis

The charity says it has been receiving a high volume of calls this month reporting sightings of species - like this waxwing - that are not usually seen in gardens Photograph: Travel Ink/Gallo/Getty Images

Many of the species, like this yellowhammer, are normally seen foraging for food in the countryside Photograph: David Tipling/Getty Images

But with the frozen conditions making it almost impossible to find natural food sources rurally, birds like this fieldfare are being increasingly seen in domestic gardens Photograph: Roger Wilmshurst/Frank Lane Picture Agency/Corbis

Finches - like this brambling - are also being seen earlier than normal. The RSPB says they usually appear in gardens closer to March Photograph: Mark Hamblin/Getty Images

Siskins are also being seen earlier than normal. Like bramblings, they are not usually seen in gardens until March Photograph: Tim Zurowski/Corbis

The redpoll is a species of finch normally found in UK woodland. But the cold weather has forced many species to look for berries and seeds in urban gardens Photograph: Mark Hamblin/Getty Images

This rare Siberian chiffchaff was spotted at a London Wildlife Trust community garden in Hackney, London. The bird, usually found in eastern Russia and Siberia is over 3,000 miles off course Photograph: Mark Pearson /wildlondon.org

A grey wagtail. The RSPB says the increased popularity of bird feeding has also had a huge impact on the number of birds seen in gardens with more species relying on supplementary food at this time of year Photograph: Tony Hamblin/Getty Images

A redwing, normally found foraging for food in fields and parks but now being seen in gardens. January is a harsh month for wildlife and birds face a constant battle to find food Photograph: Roger Tidman/Corbis

A fieldfare. The RSPB is holding its annual survey of garden birds, the Big Garden Birdwatch, on 24-25 January, and the charity says the range of species being seen in gardens bodes well for the event Photograph: Vasily Fedosenko/Reuters