DNA test to protect adders - UK's only venomous snake
Adders are the UK's only venomous snake and were once a common sight in the British countryside.
But in the past 50 years their numbers have halved as they struggle to adapt to changes in their habitat.
Scientists are now adopting a high-tech method to try to protect them.
The BBC's Louise Hubball reports from a nature reserve in Somerset.
19 Apr 2011
- From the section Science & Environment