Goldcrest. Image by Steve Round (www.rspb-images.com)

Tiny. Minute. Small.

Describe its size how you will, but goldcrests pull in a crowd. I was helping out at a bird ringing demonstration this weekend, and the goldcrests were the star attraction.

For some of the satisfied punters it was the first time they'd seen a goldcrest, let alone up so close. They vie with firecrests for the UK's smallest bird and the ones we caught weighed in at around five grams.

Five grams!

Just think, that's less than the weight of a pound coin! And some goldcrests take on a perilous crossing of the North Sea, leaving Scandinavia and crossing to the UK. Don't you think that it's amazing that a bird so small can make that journey?

This image is by Steve Round from our RSPB Images library. Did you know you can buy all our images as prints or canvasses

For more on our science, check out the RSPB Centre for Conservation Science web pages.