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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. In the early part of the month you may still see some marbled whites or skippers (large, small or Essex) but on the whole they are on the way out. Likewise gatekeepers are to be found only in the first half of the month and ringlets have disappeared entirely

To compensate, a new generation of peacocks and small tortoiseshells appear in the hedgerows, though in some years there are a lot more than in others, bad weather causing numbers to be severely reduced. (A big - and rather worrying - mystery was 2016, when the summer weather was fine but both these butterflies were in very short supply.) These are the offspring of the butterflies which appeared in March or even late February and will go on to hibernate as adults over the winter and appear again in early spring.

At a casual glance it is easy to mistake the 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.

A more common migrant 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 seem to 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, which distinguishes itself from the much dozier brimstone. The latter is a native yellow butterfly with a green underwing, whose next generation is appearing in late August, and which is another butterfly that hibernates over the winter.

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 with more orangey underwings. In any case at this time of year they seem to be in display mode, with the 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, are the large white and small white - commonly called cabbage whites. These butterflies seem to fly everywhere - in gardens, on hedgerows and verges, and 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.

A common woodland butterfly, and well camouflaged in this habitat, is the speckled wood, a dark brown butterfly with yellow spots, which can be seen throughout the month. On downland and in other grassland meadow brown butterflies are still very common.

Also on downland but also in all sorts of other habitats - on verges, in meadows - you should also see the tiny flash of blue that is the male common blue. This butterfly lives up to its name since if you see a blue butterfly away from downland, there is a good chance it is a common blue (though in 2015 and 2016 common blue numbers were much reduced). That being said, near hedgerows the holly blue is also a distinct possibility at this time of year, as it produces a second generation in late July which is common in the first three weeks of August. Telling the two apart can be a challenge. If you see the underwing, the holly blue's is a light blue 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 a rare butterfly only likely to be seen on the South Downs or in East Kent, though colonies also live on the sea-facing slopes of the Purbeck Hills near Swanage. To make matters difficult, it looks almost identical to the common blue, so would be easy to mistake for one if you just see it flitting past.

If you get a closer look, the upperwings of the adonis are lighter - a sky blue - and it has 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, so one has to look very carefully). 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 or Castle Hill nature reserve near Lewes - is the chalkhill blue, which is bigger than the adonis or common blue, 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 that 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. 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, but is sadly very rare these days.

Day-flying moths

There are all sorts of tiny day-flying moths flitting about in grassland or on flowery downland 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.

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.

Other day-flying moths I have identified in August are the common carpet, yellow shell and the snout.

Insects fade slowly

Insects slowly become scarcer during August, as they die off or get eaten, but the process is hard to quantify. There is no doubt that you can see honeybees, bumble bees, solitary bees, flies, hoverflies and other tiny flying 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.

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 various bugs and spiders, crane flies, grasshoppers and crickets that one sees scuttling close to the ground early in the month are a lot less numerous by the end, but if you look closely you can still see (and perhaps hear) them. Turn over a rotting log and woodlice and earwigs still appear, and you also see the occasional ladybird. In late August 2016 I seemed to see a lot of the invasive harlequin ladybirds - whether because they are taking over from native species or are more active than native species at this time of year, I do not know. Dragonflies continue to fly all month but damselflies are only seen at the beginning.

Spider's webs seem to become a lot more prominent in gardens as the month goes on, however: is this because they are more desperate for food and build more elaborate structures? Towards the end of the month, if dew forms on grass, you can also see the strand made by money spiders as they "balloon" - that is attach their threads to a blade of grass and then use air currents to carry them across a field.

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.

This is also the time of year that you might see flying ants - this is the mating ritual of the black garden ant, where the queens become fertilised and fly off to found new colonies. These can be quite a nuisance if you are unlucky enough to wander into the middle of their proceedings.

More August pages:

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