Neither of the most common cabbage butterflies, large white or small white, overwinter as imagos in England afaik but you could be seeing early examples of either now, although the large whites are usually marginally ahead. There are also a couple of rarer or more distinctive species, such as green-veined whites, that aren't always easy to id without a close look. Brimstones tend to exhibit very distinctive erratic flight patterns, to evade predators during the months when there are few similar prey insects on the wing, whereas the white family tend towards more average butterfly flight patterns.
Ah, thank you. I didn't know if we were far south enough for the cabbages to overwinter here.
I didn't know brimstones could be distinguished by their flight patterns, so thank you for that too - I shall watch carefully the next time I see them in my garden!
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Date: 2015-04-10 06:21 pm (UTC)no subject
Date: 2015-04-13 10:05 am (UTC)I didn't know brimstones could be distinguished by their flight patterns, so thank you for that too - I shall watch carefully the next time I see them in my garden!