Red Admiral - Vanessa atalanta
|The distinctive red and white pattern on the upper side of the wings will be familiar to most people.|
The Red Admiral, although a common feature of the British countryside, is in fact a seasonal migrant. The adult butterflies have a tendency to hibernate in exposed places and so very few manage to overwinter in Britain. In Spain and North Africa there are resident populations that breed early in the year. Those adults and their offspring continue to move northwards with the improving conditions, breeding as they go, sometimes reaching Britain in small numbers as early as March. In good years this influx of mainland European adults, combined with their British progeny can lead to large numbers of butterflies in the Autumn.
© Butterfly Conservation
The eggs are laid singly on the upper leaves of nettles - usually in the middle of large patches. After about seven days the larva emerges and immediately folds a leaf together to make 'tent' securing the edges with silk. Within this structure the young caterpillar can feed in relative safety. Several leaf tents are made as the caterpillar grows, each progressively larger. With experience these become quite easy to spot in the nettle patch. The spiny caterpillars come in two colour forms - black and a yellow green, both with yellow markings down each flank.
When fully grown the caterpillar chews part way through a nettle stem causing it to fall over. It then spins together several of these, now downward pointing, leaves to create a shelter in which to pupate. The adults emerge from the chrysalis, which is patterned with metallic gold spots, in approximately 12 days to continue the cycle.
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