While many of our familiar songbird species are in decline, one avian character in particular has been spotted increasingly frequently in UK gardens - the goldfinch.

Now, the British Trust for Ornithology wants volunteers to help work out what has boosted the bird's numbers. The organisation wants to know what goldfinches feed on in our gardens.

The aim is to work out whether supplementary feeding is helping the birds to thrive.

The increase in the UK goldfinch population has been dramatic. According to the BTO, it increased by about 80% between 2002 and 2012.

And while there are many factors and landscape changes that affect the habitat and food available to Britain's birds, the supplementary food that people put in their gardens may be having a significant impact.

A recent study, also led by the BTO, found that garden food - especially fats and sunflower hearts - had caused European blackcaps to shift their winter migration route north to the UK. The birds were apparently taking advantage of the abundant food available in British gardens.

Source: BBC

To read more please visit: http://www.bbc.co.uk/news/science-environment-34703580