Nature Menu

Introduction Beginner's Guide Where to find wild flowers Where to find butterflies Books and online tools Week by Week Nature Blog SWC_Nature

Nature and Weather in South East England

May butterflies and insects

Other May pages: Woodland, meadow and field flowersWayside flowersDownland and seaside flowersTrees and shrubsBirdsWeather

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

May sees the butterflies that hibernated over the winter giving way to others that are newly emerged. As a result the number of species on the wing increases but some of them are quite hard to spot.

Of the overwintering butterflies, small tortoiseshells may just crop up but are generally not evident after late April. However peacocks can still be seen fairly regularly in the first half of May, with the occasional one, looking rather worn out by now, right till the end of the month. Both species look almost black in flight due to their dark underwing, but have a handy habit of landing for a rest on paths, making their colourful upperwings easy to see.

The striking yellow brimstone is more abundant and lasts longer, a common sight throughout May and with some still around into June. It is a "mobile" butterfly - that is its males range widely across the countryside rather than defending a territory. For this reason they often fly past you in a hurry. Note that the female brimstone is a very pale yellow and can be mistaken for a large white butterfly: the key is its lack of black wingtips and the shape of its wing if you see it at rest.

Another overwintering butterfly is the comma, though it rarely seems to survive into May. You may just see it early in the month near bramble bushes and hedgerows, however. Also early in the month (all month in 2015, 2016 and 2019) you can see the lovely orange tip. Another "mobile" butterfly, it lasts as long as the flowers of garlic mustard, one of its favourite plants for laying eggs on. Again, the female can be mistaken for a small white butterfly as it does not have the orange tips to its wings: the key to identification is a mottled green pattern on its lower underwing.

You can only make this identification if the butterfly comes to rest, however, and that is a problem for the other commonly seen white butterflies, which seem to be especially restless. They are popularly grouped together as "cabbage whites" but there are in fact three different species - large white, small white and green-veined white. All three are on the wing this month but it is almost impossible to tell them apart as they flutter past. If you do see one at rest, then large whites have more extensive black wing tips, extending down the edge of the wing, while small whites have smaller grey tips.

Green-veined whites, meanwhile, have green stripes on the underside of their hindwing and their upperwings also have grey tips, but descending down edge in a series of blobs. They seem to make up a large proportion of the whites one manages to identify in May, but this is probably because they are slightly more inclined to settle. All three species overwinter as pupae, though large and small whites also migrate from the continent in May.

Another butterfly that can overwinter as a pupa is the speckled wood, though some also spend the winter as caterpillars. This means they have less of a pronounced season than other butterflies and are reasonably well spread throughout May. If you see a brown butterfly in a wood or on a shady verge then it is almost certainly a speckled wood. They are relatively placid and happy to settle on a leaf, so are not hard to identify.

You may also see a red admiral or painted lady during May, though usually only a few individuals are around at this time of year. The red admirals, which arrive later in the month, are migrant females who have already mated on the continent and lay eggs here immediately on arrival. Painted ladies mate once they arrive in the UK and may be seen right from the start of the month. In both cases, their offspring go on to make up a much more numerous summer generation, boosted by further migrants. Both species then travel back southwards in the autumn. Some red admirals also overwinter and survive into early spring but there is as yet no evidence that they go on to breed.

Rarer butterflies include the wall, which has brown on orange markings somewhat similar to those of the comma. Once a common butterfly on field edges, downland and railway lines, it is now only found on coasts (for example on the cliffs near Dover, on Portland Bill, on the south west coast of the Isle of Wight, on the ridge between Kimmeridge and Swyre Head near Swanage, and on the South Downs north of Shoreham-by-Sea). They like to sunbathe on paths (and also supposedly walls, hence their name) but are very flighty and easily disturbed.

May is also the month to see the wood white, a delicate butterfly that is much smaller and more feeble in flight than the common white species, and which is these days only found in a few strongholds in England. One is Tugley and Oaken Woods to the south east for Chiddingfold near Haslemere, where they are relatively easy to spot on sunny woodland rides. Another highly localised butterfly is the glanville fritillary, which can be found on the crumbling cliffs of the south coast of the Isle of Wight in the second half of the month. In 2011 some of these were also illegally introduced to Hutchinson's Bank near Addiscombe on the southern edge of London, where they still survived in 2019.

Look out also for tiny blue butterflies during the month. Near brambles, ivy bushes or hedgerows early in the month (all month in 2018 and 2019) these are likely to be holly blues, which have a pale blue underside and look a bit like a silver flash as they fly past. On grassland you may well be seeing the common blue, which can be distinguished by its brown underside with black spots: some appear from quite early in May, but they are more common in the second half.

Also later in the month, on south-facing downland slopes with horseshoe vetch growing, there is a possibility that you may be seeing an adonis blue. These butterflies live in small, discreet colonies - for example the southern slopes of Ranmore Common near Dorking and or Mill Hill Reserve north of Shoreham-by-Sea - but can be very numerous within them. Telling them apart from the common blue is a challenge. The adonis is a lighter blue, but the common blue looks fairly light in flight too in certain lights; the adonis has black lines through the tiny white borders on its wings, but the common blue has the beginnings of lines; the adonis blue male's underwing is darker than the male common blue's and with only the faintest of blue blushes near its body: and there are also slight differences in the arrangement of the black underwing spots between the two species.

The female of both these two species are brown with orange chevrons around the outside of the wing (practically invisible on the forewing of the adonis, but its female is very rarely seen). However, if you see a very small butterfly with these markings, the brown argus is also possible. Its male is smaller than the female common blue but its female looks pretty identical. Again, the minute details of the black spots on the underwing are the guide to identification. Clearing up the confusion a bit is that you sometimes see common blue females whose upperwings are partly or substantially blue in colour: this is never true of the brown argus or adonis blue.

Also brown and very tiny - the smallest UK butterfly in fact - is the small blue, yet another butterfly of downland grassland (and yes, despite its name it is brown not blue). You really have to go to a site where they are known to be in order to see them, and when you do their beige grey underwings are the key to identification. One well-established colony is on the slopes of Pewley Down near Guildford and another is on Hutchinson's Bank near Addiscombe. I have also seen them on the downs above Otford in Kent and on Compton Down on the Isle of Wight.

Once you start looking for butterflies this small, all sorts of wonders open up. May is the best month to see both dingy skippers and grizzled skippers, but you might easily mistake these tiny brown-patterned butterflies for day-flying moths, so small and inconspicuous are they. Both are mainly found in downland or short, rough grassland (try the slopes of Pitstone Hill near Tring, the downland above Shere, the lower slopes of Ranmore Common near Dorking, or Hutchinson's Bank) but they may crop up in other locations. Towards the very end of May you may also see the large skipper, a tiny orange butterfly that looks exactly like a moth, particularly in the way it folds its wings on landing.

Otherwise if you see a small orange butterfly it is likely to be a small copper or small heath. The small heath lives on grassland and is only ever found very close to the ground: it always closes its wings when it lands. The small copper is more adventurous and tends to crop up when one least expects it - on grassland, but also on flowery hillsides, even woodland rides.

One other very tiny butterfly, looking brown in flight, is the green hairstreak. It is fiendishly hard to spot when at rest due to its green underwing, which means it blends in with the downland shrubs it usually perches on. Try Aldbury Nowers near Tring, the North Downs above Shere, Hutchinson's Bank or the lower slopes of Ranmore Common.

Day-flying moths

It is easy to mix all these small butterflies up with various day-flying moths that are also on the wing in May. Dingy or grizzled skippers, for example, look very similar to brown moths such as the burnet companion and the mother shipton (both grassland species and both easily confused with the dingy skipper butterfly, as noted above). The fairly common speckled yellow, found in various types of habitat including hedgerows and downland, also looks like a small butterfly.

Perhaps the main difference between moths and butterflies, however, is that moths immediately head for cover when disturbed. This is certainly true of the white common carpet, silver-ground carpet, and the treble bar, all of which can be also found along hedgerows, in grassland and in a range of other habitats. Less easy to confuse with butterflies are the bright red and black five-spot burnet and, occasionally, the equally colourful cinnabar moth.

Other moths you may encounter include the lace border, found on chalk grassland in the North Downs, and the yellow belle, which is mainly coastal. At the end of the month you may see the black chimney sweeper moth in meadows in which pignut grows. Note also the very tiny micro moths, of which the small yellow underwing is one, as well as grass veneer moths, which look like tiny white butterflies as they flit around grassland but then close their wings when they come to rest and almost completely disappear.


April has already seen quite a lot of tiny insects emerge (it is one reason those summer visiting birds come to our shores) and this continues into May.

One that you may occasionally see early in the month in large swarms is the St Mark's fly. Its legs trail below it as it flies, making it look rather sinister, but it is in fact quite harmless. Its name refers to the 25th of April, the feast of St Mark, when it traditionally appeared. Alexanders are a favourite food plant, so it may be easier to see in coastal locations, but it is also found inland.

Otherwise, there are plenty of bees around - honeybees, solitary bees and also bumble bees. Solitary bees mate like any other insect and then the female lays eggs, with nectar for food, and seals them up until the larvae emerge as adults. Bumble bees are still queens earlier in the month. They mated in the late summer last year, hibernated fully-fertilised until March and then spent the early spring flying around look for nest sites. By the start of May their nests have been established and from around mid month the slightly smaller workers start to emerge. From this point on the queen never leaves the nest again; she essentially becomes a baby machine.

Other insects have evolved to look like bees for protection from predators - this is true of several species of hoverfly, which are by now to be seen everywhere (they can easily be distinguished from bees by their charming capacity to hover absolutely immobile in mid air). Notice also the bee fly, a hovering fly with a fat furry body which is found more in the early part of the month. House flies (aka bluebottles) are also about and as the month goes on can become a nuisance, buzzing around your kitchen.

May also sees a lot of other flies of various sizes, as well as tiny insects ones that congregate on buttercups or dandelions, fly into your mouth when you are running or cycling, swarm at dusk, or produce itchy bites on your arms and legs. One becomes aware of the amazing variety of insect life, most of which passes beneath our attention.

Ladybirds - particularly the common seven-spot ladybird - are mating in May: you can sometimes catch them in the act. Their larvae go on to feed on the late spring and early summer plant growth, with new adults emerging in the late summer to feed up and then hibernate. The invasive harlequin can also be seen in a variety of different liveries: it breeds all summer, outcompeting native species.

May is also a good month to see shield bugs of various types, which have similar life cycles to those of seven-spot ladybirds. Thus the green shield bugs and dock bugs have emerged from hibernation and are now mating, laying eggs that will hatch into a new generation at the end of the summer. Mating is also uppermost in the mind of a multiplicity of beetles in May, particularly later in the month, including the black bloody-nosed beetle, bright red cardinal beetles, and iridescent green rose chafers and swollen-thighed beetles. Other insects to be seen include pondskaters on still water and crane flies in grassy fields.

As the month goes on you can also see dragonflies and damselflies, including the beautiful banded demoiselle with its hypnotically patterned double wings; less commonly also the beautiful demoiselle with its striking brown wings. Look for both of these jockeying for the best position on fronds of vegetation on river banks. The most often seen damselfly is the common blue damselfly but it is only the males of the species that have this colouring: the females can be green, blue, black and white or straw-coloured apparently, while newly emerged males have black and beige markings. To see the two clutched in their rather brutal mating clasp is not unusual: they even fly through the air in this posture. There is also a blue-tailed damselfly with black body with a blue tip, large and small reds, and an emerald damselfly. Banded demoiselle females are green too, becoming more bronze with age, while the males are metallic blue. Dragonfly species include the broad-bodied chaser and the black-tailed skimmer.

By rivers towards dusk - particularly chalk streams - look out for swarms of mayflies dancing up and down in the air. You can see them even in early May and indeed later in the summer, but late May or early June is the peak time. A clue to identification are the three long tail filaments visible as they float downwards in their dance and the striped black and white tips to their abdomens. One of the most ancient creatures on the planet, they actually moult twice as an adult, the only insect to do this. They first emerge during the day as dull brown sub-adults that struggle to work out how to use their new wings, taking off and then landing again (a process imitated by fly-fishing) and often getting eaten by trout or birds in the process. If they reach the safety of a nearby bush, they moult a second time into full adults, taking to the air later in the afternoon. In this form they have a digestive system which doesn't function, so they cannot eat: they therefore live only for a night or two, just long enough to mate.

This is also the month that you see cuckoo spit - the saliva-like liquid on plants that is actually produced as a protective layer by the larvae of the froghopper (so called because the adult makes sudden big jumps: spittlebug is not surprisingly another name for this insect).

More May pages:

© Peter Conway 2006-2019 • All Rights Reserved

No comments:

Post a Comment