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August butterflies and insects

Other August pages: Berries, fruits, nuts and treesFlowersBirdsWeather

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

The number of butterfly species starts to reduce in August, but you still see plenty of them on sunny days in places where there are still flowers for them to feed on. At the start of the month you may just see some marbled whites but they are definitely on the way out, while ringlets have disappeared entirely. Gatekeepers are to be found only in the first half of the month (just possibly into the third week).

Skippers (probably large, though small or Essex are possible) are also only seen in the first few days of the month, if then, but there are two very localised exceptions to this. One is the the Lulworth skipper found on the hills above that Dorset cove, best early in the month but visible till its end. The other is the silver-spotted skipper, found on some downland slopes in the south east, for which this is the best month.

Otherwise, in hedgerows a new generation of peacocks is supposed to appear in late July and early August. These are the offspring of the butterflies which appeared in March or even late February and will go on to hibernate (or, to be more accurate, diapause - a complete cessation of metabolic activity) over the winter, appearing again in early spring to breed. In recent years (2014 to 2017) there have been worryingly small numbers of these summer peacocks, however. A particular mystery was 2016 when summer weather was favourable but very few were seen, and there was no uptick in the admittedly less favourable weather of August 2017.

There is a similarly worrying picture for small tortoiseshells. In the second half of the month (occasionally earlier) there can be an extra generation, the offspring of the ones that appeared in late June and early July. This only occurs in good summers, however, and the last time it happened to any degree was in 2013. This another common butterfly that has seen worrying declines in recent years. Like peacocks, any you see now will go on to hibernate over the winter.

At a casual glance it is easy to mistake a small tortoiseshell for the painted lady, a butterfly that migrates in several generations from Morocco in favourable summers, and which can be quite common in August, particularly near the south coast. In some years one sees hardly any, however (for example 2017 when the author saw none).

A more common migrant - and one that does seem to have thrived in recent years - is the red admiral, seen in hedgerows. From mid August some are starting to head south again but they remain widespread into the autumn and some even spend the winter here. Males are often patrolling a territory, so if you disturb one, stand still and it may well come back.

On downland, particularly near the coast, you may also be lucky enough to see another migrant, the clouded yellow. It has a hint of orange in its upper wing and flies past very fast. If it settles, it closes its wings, showing only its green-yellow underwing. It is not to be confused with the much commoner brimstone, a native yellow butterfly with a bright yellow upperwing, which also closes its wings when it settles, revealing a lime green underwing with a very characteristic shape. A new generation of these emerge in August and they will be very long-lived, hibernating over the winter and lasting as adults until well into June in some cases. Contrast this with some other butterfly species (common blues, for example) that may only live a few days.

If you see a flash of orange in the hedgerow, it is most likely to be the striking comma, another butterfly destined to hibernate over the winter. With their wings closed they look just like a fragment of dead leaf, but in hotter summers a variant is produced in early July with more orangey underwings: these go on to produce a further generation later in August. In such years ones you see at this time of year could be survivors from July or new adults. In either case in August they are in display mode, perching prominently with their upper wings open. Like red admirals they often swoop back and forth across a particular spot, returning to the same perch you disturbed them from.

Easily the most widely seen butterflies in August, however - though not in 2017, when numbers were very muted - are the large white and small white, commonly called cabbage whites. These seem to be everywhere - in gardens, on hedgerows and verges, and flitting across arable fields. Since they rarely seem to rest it is hard to get a close enough look at their wing markings to tell them apart. The same applies to the green-veined white, which is distinguished from the other two by the green veins on the underside of its wings and can still be seen right to the end of the month. Be aware also that some apparent large whites may in fact be female brimstones, which are a pale green-white colour. The shape of the closed wing when at rest should settle the matter: brimstones also never rest with their wings open.

In woodland, the most common butterfly is the speckled wood, a dark brown butterfly with yellow spots, which can be seen throughout the month. They are well camouflaged in this habitat but have a gratifying habit of basking on a sunny leaf, making them easy to see or photograph. In the early part of the month you may also see the magnificent orange silver-washed fritillary in clearings near woodland - for example, feeding on buddleia or any remaining bramble flowers - though they tend to be looking rather tatty by this point.

In theory both the magnificent purple emperor and the much smaller but still impressive purple hairstreak butterfly can also be seen this month, but they live in the top of oak trees and are only spotted on rare forays to the ground (in the case of the purple emperor to imbibe minerals from soil or animal faeces). Also living in tree tops, though this time on ash, is the brown hairstreak, for which August is the best month. With this species, the key is to catch females on fine sunny days coming down to lay eggs on blackthorn bushes or to feed on bramble, thistles or hemp agrimony.

Slightly easier to see if you know where to look is the very rare wood white. Confined to a few pockets, this very small and feeble-flying white butterfly (it does not look like any of the other white species) is nevertheless fairly conspicuous if you are in the right place. One such is Oaken Wood to the south west of Chiddingfold in Surrey. You can find other locations where it is present on the internet.

On downland and in other grassland meadow brown butterflies are still very common - almost boringly so. They last most of the month, fading towards its end but with a few lasting into September. Much more exciting is to see the tiny flash of blue that is the male common blue, which is well-named as it is by far the most common blue butterfly that you are likely to see. (Thankfully, it seemed to have a much better year in 2017 after two poor ones in 2015 and 2016).) It is usually found on downland, but sometimes in other grassy places.

Near hedgerows (and particularly around ivy) the holly blue is also a distinct possibility, however, as it produces a second generation in late July which is on the wing in the first three weeks of August. Telling it apart from the common blue can be a challenge. If you see the underwing, the holly blue's is a light blue (it can look silvery in flight) while the common blue's is light brown. Holly blue females also have a black tip to their upper forewings.

On flower-rich south-facing downland in the second half of August another possibility is the adonis blue, which produces a second generation at this time. However, this is another butterfly that is only found in certain locations (one is the lower slopes of Ranmore Common near Dorking: another is the Yeosden Nature Reserve near Saunderton in the Chilterns). It likes south-facing downland slopes and looks almost identical to the common blue, though if you see the two together you can see that the adonis has upperwings of a brighter, lighter shade of blue. (Be careful, though: seen in isolation, the common blue's also look light and bright).

If you get a closer look, the adonis tiny dark lines through the white border of its wings (though common blues also have slight dark marks on the inside edge of the border: often only a photograph settles the matter). The underwings of the adonis are also a more chocolatey brown than those of the common blue.

Much easier to see on flower-covered chalk downland - try the southern slopes of Pewley Down near Guildford, Castle Hill nature reserve near Lewes, or the lower slopes of Ranmore Common - is the chalk hill blue, which is bigger than the adonis or common blue and somewhat paler. It can look almost white in flight, but is clearly blue when you see it at rest - and has black veins and distinctive black edging to its upperwings and black veins. Populations of this butterfly are at their best in the first half of August.

The holly blue apart, the females of all these blue species are all brown, with orange dots around the edge of their wings. Differences between them are subtle, and if you see a tiny butterfly fitting this description it might be the rare brown argus. See the July butterfly page for more discussion on this. While the brown argus is mainly seen on downland, it can also be seen on heather-covered heathland during August.

Another tiny butterfly of grassland and low scrub - orange in flight, but only ever seen at rest with its wings closed - is the tiny small heath. In photographs it looks quite similar to the meadow brown or gatekeeper in this pose, but its minute size makes it easy to distinguish from these two. It is also always close to the ground, never being seen above a metre or so in height. A new generation of these butterflies is usually emerging as the month goes on, so you are more likely to see them at the end of the month.

A tiny butterfly with orange and red markings that you may just see during August is the small copper. If you see a butterfly with black and orange markings like the comma, but with an eye on each wing, it is a wall - this butterfly is found especially on heaths and grassland near the south coast (try Portland Bill or the cliffs between Folkestone and Dover), but is sadly very rare these days.

Day-flying moths

There still a good number of day-flying moths flitting about on verges or in flowery grassland in August - in particular the tiny white grass veneer moths which snap shut into a thin line as soon as they land making them almost invisible. You probably need to be a specialist to identify most of these species, but in early August the striking red on black spots of the six-spot burnet make it easy enough to see: it is particularly fond of knapweed and ragwort flowers, but tends to have faded away by mid month.

You also continue to see - or disturb - various small white moths on path verges and downland - for example the common carpet, chalk carpet and lace-border - all of them perhaps commoner in the early part of the month. The treble bar is a greyer colour.

Other day-flying moths I have identified in August include the yellow shell, shaded broad-bar and the snout, as well as the tiny mint moth, found particularly feeding on herbs such as marjoram and also known as a small purple and gold after its colourings. On one occasion in Eastbourne I was also lucky enough to see the enormous hummingbird hawkmoth, a migrant from southern Europe which is most likely to be found on the south coast.

August can see an influx of silver Y moths, a migrant which can arrive in quite some quantities on the south coast, and which are especially active later in the afternoon. They are large - about the size of a meadow brown butterfly - with greyish with white markings on their wings, but their constant buzzing flight makes it hard to see this. There were lots on Beachy Head in the third week of August 2013.

Insects fade slowly

Insects slowly become scarcer during August, as they die off, get eaten or become dormant, but the process is hard to quantify. There is no doubt that you can see some insects right to the end of the month, and indeed into September. In certain places they may even still be abundant - for example bees buzzing around late summer lavender. But if you compare their general frequency at the start and end of the month, there is a noticeable reduction - a real sign that summer is coming to an end.

All this is somewhat weather-dependent. In 2016, when August had a hot sunny end insect life continued fairly vigorously into the second half. In 2017, a changeable and rather cool summer, there was a dramatic reduction after mid month. In both years hoverflies were hardly seen after the first week, though even in 2017 there was a variety of flies - flesh flies, blow flies, house flies - right to the end of the month.

The bumble bees you see flying around in August are increasingly likely to be new queens. Late in the summer these emerge from their colonies and mate with males, who are produced towards the end of the season. All but the new fertilised queens then die off in the autumn: towards the end of summer you may see them feeding up before finding themselves a hole to spend the winter in.

Honeybees live in colonies all winter - they make honey to keep themselves fed - so they can still be seen out in force wherever there is nectar for them to eat. Solitary bees overwinter as adults or as larvae, depending on species: some are still around in August, though they get scarce later in the month.

Wasps seem to be exception to the general decline in insects, but this is mainly because they become a particular nuisance to humans eating outside in August. Earlier in the summer they are living in colonies and the worker wasps are busy feeding the larvae on a diet of crushed insects: they in turn are fed by sweet secretions produced by the larvae. But as the summer draws to an end the young queens and males fly off to mate, and the colony breaks up. The workers, now redundant, go off in search of rotting fruit and other sugar-rich foods. The result is a pleasant retirement for the wasps before they die off in the autumn, but a plague for our picnics, teas and pub gardens.

In contrast to all this decline, there are some bugs that are actually emerging as adults in August, their parents having mated in spring and their offspring having spent the summer as larvae and then pupae. An example is the dock bug and also the seven-spot ladybird. Towards the end of the month they are joined by a new generation of green shield bugs. All of these feed up in the late summer sun and then hibernate to breed next year. By contrast the invasive harlequin ladybird has been active and breeding all summer - an advantage it has over native ladybird species which breed only once a year. In late August 2016 there were a lot of them about.

By late August your arms and legs also no longer get covered in midge bites, and a lot fewer insects invade your house if you leave a window open. The crane flies, grasshoppers and crickets that one sees close to the ground early in the month are less numerous by the end, but if you look closely you can still see them. Ants continue to be active above ground all month and you may see an eruption of flying ants: this is the mating ritual of the black garden ant, where the queens become fertilised and fly off to found new colonies.

There continue to be lots of spiders hidden away in grass and among plants. The early morning dew in late summer means you can see the threads money spiders make as they "balloon" - that is attach their threads to a blade of grass and then use air currents to carry them across a field. In gardens spider's webs seem to become a lot more prominent as the month goes on. Is this because they are more desperate for food and build more elaborate structures? You can still see the long-legged harvestman (a close relative of spiders), and pondskaters can still be found on the surface of still water.

Damselflies can sometimes be seen in August, but are much scarcer than earlier in the summer. The common blue damselfly remains the most often seen species: banded demoiselles are possible also at the very start of the month. Dragonflies continue to hunt unabated, with various species to be seen. Identifying them is difficult because they rarely stop to rest and have 360 degree vision to spot you if you try to get close. But the common darter is one August species and the striking southern hawker is another.

More August pages:

© Peter Conway 2006-2017 • All Rights Reserved

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