Things are looking up!
Lepidopterist and friend of Encounter Matthew Oates has an update on how this year’s butterfly season is unfolding
Painted lady butterfly
The fine spring is turning this into a very promising butterfly season following a shocker last year, due to miserable summer weather. Butterflies are boom and bust specialists, so their populations are prone to massive fluctuations. We’re due a boom!
Already, we have had immigrations of two of our more regular migrants, the red admiral and painted lady. Red admirals lay surprisingly small eggs on taller nettles in sunny positions. The black, spiny larvae then develop within folded up nettle leaf ‘tents’, spun up with silk (though there’s a common moth, with green larvae, which does something similar).
The painted lady is a long-haul flight specialist, often coming here from the northern edge of the Sahara, or at least from the Mediterranean region. Its larvae are thistle feeders, and in years of abundance they can defoliate whole stands of thistles.
If they arrive early, as they are doing this year, red admirals and painted ladies produce significant home-grown broods. The autumn broods then emigrate south.
Small white butterfly
Cabbage white numbers are massing already. We have two species: the large white and the small white. However, their identification is not always easy, as there are some small large whites and some large small whites. Confusion is increased by the green-veined white, which is of similar size to the small white, but has grey-green wing veinage, prominent on the undersides. It has produced a strong spring brood this year, though that will end soon. But fear not, identifying these whites does become easier in time.
Come July, cabbage whites could be quite numerous, especially if they are also doing well on the near continent, as they can migrate here across the Channel.
The two cabbage whites breed on a variety of closely-related plants, wild and cultivated. They are by no means dependent on cabbages, but gardeners beware: net your cabbages with fine netting. You can have the best of both worlds by growing nasturtiums, which large and small white caterpillars relish.
In the countryside, cabbage whites breed on brassica crops (cabbage family), which are often planted along field edges as pheasant and/or wild bird winter feed crops, and on rogue oilseed rape plants growing along roadsides. The larvae crawl significant distances before they pupate, and the butterflies are incredible wanderers.
Fingers crossed for a great butterfly summer!
Painted lady by Jeffrey Hamilton on Unsplash; small white by AG ZN on Pexels.
