The Red Admiral butterfly is one of several British butterflies that can theoretically be seen all year round. The vast majority migrate here from Europe, but they can occasionally hibernate over winter, and on a sunny winter's day, you may see one flying (I've certainly seen them in December and January). When they overwinter they can get extremely worn and tatty. Red Admirals normally arrive in May/June and their young hatch in August/September. They have a partially dull underside, the pattern is mainly for camouflage when in hibernation (the upper wing will tuck behind the lower). It is a large butterfly, and the vivid red, black and white pattern makes it an easy one to identify.