Media playback is unsupported on your device

Sir David Attenborough urges public to count butterflies

18 July 2014 Last updated at 11:00 BST

Sir David Attenborough has called on the public to go out and spend 15 minutes counting butterflies in their local area.

Speaking ahead of the launch of the Big Butterfly Count, Sir David said it was an "invaluable" example of citizen contribution to science.

Sir David added that indications from caterpillar numbers were "exciting" ahead of this year's count.

Broadcast on BBC Radio 4's Today programme on Friday 18 July.

BBC © 2014 The BBC is not responsible for the content of external sites. Read more.

This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.