31-Mar London’s Butterfly Bonanza

Summary

Fluttering Jewels: London’s Butterflies Herald Spring

March brings a kaleidoscope of colour as London’s butterflies take to the skies. The sulphur-yellow Brimstone, with its nomadic wanderings, often steals the show, while the fiery Red Admiral and the enigmatic Peacock add drama to gardens. In woodlands, the dappled Speckled Wood flits through sunlit glades. But it’s not just the adults—caterpillars are thriving, hidden among nettles, grasses, and budding leaves. Will you spot the first Orange-tip or Holly Blue of the year? Join us on 31 March to celebrate the dazzling return of London’s butterflies. Don’t miss this vibrant spectacle of spring!

Article

Butterflies

It is rare to see your first butterfly in February but if you have not seen one by mid March just keep your eye open on the next warm day. The first one often gives a brief moment of excitement in much the same way as the first snowdrop or first swallow. For most butterfly enthusiasts it will be a Brimstone they are hoping to see. The males are large, fast flyers but instantly recognisable by their sulphur colour. The females are also large and although the palest green are sometimes confused with large whites. She is a stronger flyer than a white and has no black wing tips like the similar large White. Brimstones are the longest-lived of our butterflies which explains why they can be seen in almost every month of the year. Even though an individual may live for eleven months it is generally most appreciated in March.

31-Mar London’s Butterfly Bonanza Section Image

31-Mar London’s Butterfly Bonanza Section Image

Compared with other butterflies they are true nomads, often seen considerable distances from their food plants. These are both the common and alder buckthorns. The first is largely restricted to the North Downs and the second prefers wet woods and alder carrs. However, this doesn’t seem to matter as we generally see them in the most unlikely of places such as at the edge of busy roads, even in central London.

31-Mar London’s Butterfly Bonanza Section Image

31-Mar London’s Butterfly Bonanza Section Image

If it is not a Brimstone butterfly you see it will probably be either a Comma, Red admiral or Peacock in a garden or Speckled wood if in woodland. Luckily they can all be recognised at a glance which is often all we get. Commas are usually given away by the ragged edge to their wings. They are brown and the only other brown butterfly this month is the Speckled wood which is more dappled and nearly always seen in woodland. Red admirals are usually betrayed by a flash of signal red and Peacocks in flight usually look black before they invariably seem to disappear.

Although adult butterflies may be still uncommon their caterpillars certainly are not. They are often small and green and now is a good time to look for them on their food plants. Many live in discreet colonies which can make them a little easier to find. Blues prefer trefoils, vetches and rockroses on chalky downland, except for the holly blue which prefers the young shoots of holly. The Browns tend to go for grasses particularly cocksfoot, meadow grasses, bromes, bents and fescues.

31-Mar London’s Butterfly Bonanza Section Image

31-Mar London’s Butterfly Bonanza Section Image

If there are any large Vanassids about they are often attracted to nettles. Small coppers are much more particular. They only eat Common and Sheep’s sorrel and even then only certain forms.

31-Mar London’s Butterfly Bonanza Section Image

31-Mar London’s Butterfly Bonanza Section Image

White admiral caterpillars are best looked for on unfolding honeysuckle leaves and there is only a miniscule chance of coming across any purple emperor caterpillars on goat willow leaves. It may also be worth looking at the opening buds of oaks for purple hairstreak caterpillars and those of elm for any white-letter hairstreaks. As it gets to the end of the month more adults may be coming onto the wing. The small, green-veined and large white as well as holly blue and even orange-tip are all now possibilities.

31-Mar London’s Butterfly Bonanza Section Image

31-Mar London’s Butterfly Bonanza Section Image