To see one, look everywhere as they are common in gardens and may be found anywhere in Britain and Ireland and in all habitat types! Watch them feeding on rotting fruit because their behaviour changes. They are less scared, which people think might be because the fruit juice has turned to alcohol and they are slightly drunk!
Believe it or not, but the Red Admiral (
Vanessa Atalanta), one of our most common butterflies, is not considered to be native to Britain! Each spring and summer, they make their journey from North Africa and mainland Europe to the UK. When they arrive, the females lay their eggs, which hatch from July onwards, adding to their numbers. They are usually the last butterfly of the year to be seen flying and the best places to spot them are on garden buddleias, flowering Ivy and rotting fruit. Although it now seems that a few might hibernate here in the far south of England, most can’t survive our cold winters and will die.
For more info see
https://butterfly-conservation.org/butterflies/red-admiral