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April butterflies and insects

Other April pages: Intro and woodland flowersVerge and field flowersBlossom and shrubsThe greening of the treesBirdsWeather

Put your cursor over any photo on this page to see its caption, or click here to see more April butterfly and insect photos. For more information on butterflies and moths see the Butterfly Conservation website.

Butterflies can be quite abundant on warm days in April. Peacocks, small tortoiseshells, commas and the bright yellow brimstone (the original "butter fly") all overwinter as adults and become active when the sun shines (ideally when the temperature goes above 15 degrees, though this does not seem to be a hard and fast rule).

Small tortoiseshells and peacocks look dark in flight (the colour of their underwings) and you only can see their colourful upperwings when they settle. Fortunately they have a convenient habit of basking on paths, making them easy to spot. Commas are much scarcer at this time of year (they are more abundant when they have their second generation in the summer) but can be found near hedgerows and banks of bramble.

Brimstones fly past in a hurry and almost never seem to rest: when they do they close their wings, so all you can see is their green (and very well camouflaged) underwings. Males are the ones most usually seen: the females have upperwings that are almost white and paler green undersides. But if there is any doubt, the shape of the wings clearly distinguishes them from the white species.

In 2017 there were also some red admirals to be seen in the first half of the month. These migrant butterflies do not arrive from the continent till May, but some manage to overwinter from the previous year, going into an inactive state known as a diapause in the same way as the peacocks and small tortoiseshells. It is not unheard of to see them on milder days in the winter months, but surviving into spring seems to be a new trend. There is as yet no evidence that they go on to breed, however, especially as the May arrivals are already mated females who are just looking for a place to lay eggs.

Speckled woods can overwinter as pupae or caterpillars and may just be seen in the first half of April, though the second half is a more normal time. They are found in woods and shady places. The three white species commonly known as cabbage whites - the large and small white and the green-veined white - also overwinter as pupae and may be seen from quite early in April, with the small white typically the first to appear. These are very hard species to tell apart because they are even more flighty than other butterflies and very hard to identify until they settle.

If you can find one at rest, the green veins on the underside of its wings are a reliable guide to the green-veined white, while large whites have much larger black tips which extend down the wing edge. On the small white the dark wingtips are smaller and more greyish. Both small and large whites have somewhat yellowy underwings for camouflage purposes and for this reason it is just possible that you might mistake one in flight for a brimstone. Contrawise, the paler yellow female brimstone can look like a large white as it flies by.

Perhaps the most lovely April butterfly of all, however, and the only one that is exclusively found at this time of year, is the orange tip. It lays its eggs on cuckoo flower and garlic mustard and so is particularly in evidence along country lanes in mid to late April when those plants are in flower. The orange tipped wings of the male make it easy to identify in flight. The lower underwing is a mottled olive-colour that disguises it perfectly against vegetation. This is the only way to identify the female, which does not have an orange tip and otherwise looks remarkably like a small white.

You can also see the holly blue, which has a deep blue upperwing and a pale blue underwing with spots. It is the only blue butterfly at this time of year and often can be found circling around and landing on bramble, ivy and holly (on which it lays its eggs). Females have a large black border to their upperwings while males have a very thin one at their wing tip. In flight both can look almost silver.

Other insects

The number of insects increases rapidly in April - they are the reason migrating birds return at this time and chose England to breed in. Bees - bumble bees, honeybees and other solitary species (such as the grey mining bee) - are particularly in evidence around trees in blossom. You might not immediately see then, but sit below a flowering blackthorn or cherry tree and you can hear a very summery hum. Oilseed rape flowers are another place to see them.

The bumble bees are queens - the sole representatives of their species to overwinter. At this time of year they fly around and feed and look for nesting sites. Later - in May - they will become confined to the nest and become machines for turning out young, so you might say that in April they get their little bit of freedom before the hard work begins. Though less often seen, queen wasps are also out and about on the same mission - looking for a nesting site (perhaps in your loft...).

On a warm day the air can also be full of tiny flying insects: dandelions are a particularly good place to see them, and you also get swarms over rivers. Not all of these insects are "gnats": one swarm I managed to photograph in April 2017 was identified by those more expert than me as a species of (tiny) parasitic wasps. If you look closely you can see all sorts of other creepy crawlies such as spiders, ladybirds and crane flies.

There are also hoverflies right from the start of the month as well as common house flies - but the latter never seem to be a nuisance, as they can become later in the summer. In addition, note the intriguing bee fly, which has a fuzzy brown body and seems to like April blooms such as cuckoo flower and blackthorn.

Towards the end of the month you may see swarms of St Mark's flies, so called because they are supposed to appear around St Mark's Day which is 25 April. The legs of these flies hang down below them, looking rather like a sting, but they are in fact quite harmless. They are particularly fond of cow parsley and alexanders flowers, on which they can settle in great numbers. (In 2015 and 2016 I failed to see any in the south east, though there were huge swarms of them in Cornwall in early May. I saw a very few in the south east in 2017.)

More April pages:



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