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April butterflies and insects

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

Picture: peacock butterfly. 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. Both have a convenient habit of basking on paths, from which they fly up when walkers approach, and peacocks also seem to fond of feeding on blackthorn blossom, which makes for great photos. Neither one has been quite as common as it ought to be in recent years, with small tortoiseshell numbers particularly reduced, though one exception to this was the warm sunny April 2020, when peacocks were quite abundant and small tortoiseshells saw something of an uptick. Commas are fairly elusive at this time of year (they are more numerous when they have their second generation in the summer) but can be found near hedgerows and banks of bramble.

Brimstones are much more frequently seen. The bright yellow males (they are the original "butter fly") hurry past at great speed and almost never seem to rest, but are easy to identify on the wing. When they do stop, they close their wings, so all you can ever photograph is their green (and very well camouflaged) underwings. Females have upperwings that are almost white and paler green underwings, and in flight can easily be mistaken for a large white. But the shape of their wings - or a sight of their underwings - soon settles the argument.

You may also see some red admirals 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. In 2020 red admirals did not appear till the last ten days of April, suggesting they were perhaps early migrants.

Speckled woods can overwinter as pupae or caterpillars and may be seen in woods and shady places in the first half of April, though the second half is a more normal time. 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 and the green-veined soon afterwards.

These three whites are very hard to tell apart because they are even more flighty than other butterflies and almost impossible to distinguish until they settle, which they rarely do. Whether because they are more common in April or more likely to stop for a feed, many you do find at rest at this time of year turn out to be green-veined whites. As their name suggests, they have green veins on the underside of their wings, and the grey patch on their wing tips is more broken up, while on the small white it is a neat triangle. Large whites have larger black tips which extend down the wing edge, but are much more elusive than the other two species this month. Both small and large whites have somewhat yellowy underwings for camouflage purposes and for this reason it is possible that you might mistake one in flight for a brimstone. As mentioned above, the paler yellow female brimstone can also look like a large white as it flies by, as indeed can a male brimstone at a distance.

The female orange tip butterfly can also easily be confused for a small or green-veined white until you see its distinctive mottled olive lower underwing. The much easier to identify male is the one you will usually notice, however - perhaps the most lovely April butterfly of all, and one that is easy to identify even in mid flight, since it lives up perfectly to its name. Orange tips are only found at this time of year, and their adult phase coincides exactly with the appearance of cuckoo flower and garlic mustard along country lanes in April. The female carefully lays one egg per stem on either of these plants and the caterpillar then eats the plant's seeds and becomes a chrysalis, in which form it remains until the following spring.

From the second week of April 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 butterflies that may appear towards the end of April include the dingy skipper and grizzled skipper, both very small and nondescript brown butterflies that you could easily mistake for day-flying moths. Both particularly like downland habitats, but can be found elsewhere. Equally hard to spot unless you see it landing is the green hairstreak, a tiny butterfly with brown upperwings and a bright green underwing that is perfectly camouflaged against the shrubs it likes to perch on, always with its wings closed. The bright orange but elusive small copper is also just possible at the very end of April and I have twice seen small heaths in grassland at this time.

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. Honeybees, which live in colonies all winter, are particularly in evidence around trees in blossom. You might not immediately see then, but stand below a flowering blackthorn or cherry tree and you can hear a very summery hum. Oilseed rape fields in flower are another good place to hear this.

You also see lots of queen bumble bees. These are sole representatives of their species to overwinter and at this time of year they fly around close to the ground, looking for a hole in which to create a new colony. When they have found a suitable site, they amass a lump of pollen larger than themselves to provide food for their first offspring. Once the colony is established - usually sometime in May - there are workers to do the food gathering and the queen spends the rest of her life underground, becoming a machine for churning out larvae. So you might say that in April they get their little bit of freedom before the hard work begins.

There are various species of queen bumble bee, including buff-tailed, white-tailed and garden bumble bees, all of which look rather similar, and the red-tailed bumble bee, which is a bit more distinctive. Notice also the common carder bee with its tawny thorax, which is particularly fond of flowers such as red and white deadnettle.

There are many other solitary (ie, non-colony dwelling) bee species. Some look like bumble bees, such as the hairy-footed flower bee (the males golden, the females black), a common early spring species that likes to feed on lungwort and grape hycacinth, while others look more like honeybees - particularly various types of mining bees (early, grey, tawny, yellow-legged...). Solitary bees can also be distinguished from honeybees or bumble bees because the latter make a humming noise in flight, which solitary bees do not. Though less often seen, queen wasps are also out and about on the same mission as the queen bumbles - looking for a nesting site (perhaps in your loft...).

Solitary bees can be quite hard to tell apart from hoverflies, which can be seen right from the start of the month. Many of these have evolved to look like bees in order to put off predators, but as their names suggest, they are able to hover in mid air, something no bee can do.

Another notable example of a fly mimicking a bee is the charming bee fly, which has a fuzzy brown body and hovers in mid air feeding on flowers much like a hummingbird, using its long proboscis. They are particularly fond of grape hyacinth, though visit a wide range of species. Less charmingly, they parasitise on the young of solitary bees and wasps - that is, they lay their eggs in the nests of such species, so that their young can eat their larvae. Only seen in spring, and so very characteristic of this time of year, they carry the bee imitation as far as making a very bee-like buzzing noise.

You also get common house flies and smaller versions of the same - but the former rarely seem to be a nuisance, as they can become later in the summer. In general on a warm day the air can be full of tiny flying insects: you get swarms over rivers or in the air towards dusk or can see them feeding on flowers. Not all of these are "gnats": Some I managed to photograph in April 2017 were identified by those more expert than me as (tiny) parasitic wasps, while later in the month you may see swarms of what look like tiny flies with silvery wings, but with a more fluttering flight, which are in fact a day-flying moth, the green longhorn. I have sometimes recorded crane flies in April too.

There are also a series of species known as March flies - tiny little flies that appear in swarms. In both 2018 and 2019 I have seen them on wood anemones and once in 2019 on bramble leaves. A rather larger member of the group are 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 also swarm and are particularly fond of cow parsley and alexanders flowers, on which they can settle in great numbers.

Ladybirds are also out and about, particularly the seven-spot ladybird, though other species may be seen if you are lucky (for example the tiny twenty four-spot, a grassland species, and the cream spot, which lives on trees and hedgerow shrubs). Native ladybirds emerge as adults in the late summer, feed up and then lay dormant over the winter and emerge in early spring to mate and lay eggs. The invasive foreign harlequin ladybirds breed all summer, which unfortunately gives them an advantage over the indigenous species.

Dock bugs and shield bugs of various kinds also emerge from hibernation in late April and look for a mate. You can also see tiny bugs and beetles crawling about on the flowers of dandelions, lesser celandines or daffodils that only an expert could identify. Spiders are increasingly active but not very conspicuous, and ants have by now resumed their activities above ground.

More April pages:


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