The Purple Emperor, also known as ‘His Imperial Majesty’, is a magnificent but elusive species that spends most of its time high in woodland canopies, feeding on aphid honeydew. They are one of the rarer species found in London and their evasive nature combined with a relatively short flight period (July) meant I was especially worried about achieving them as one of the ‘ticks’ on my 33 Butterflies Challenge.
I had scoured records from previous years on local Butterfly Conservation ‘sightings’ pages so had a few ideas of possible sites then spent the first couple of weeks of July checking Twitter every day. Thankfully, due to their celebrity status in the British butterfly world, people who see Purple Emperors will often post photos on social media. One such post was from a garden on Putney Heath in Wandsworth and after sliding into DMs to confirm a specific location I waited for the next super sunny morning to stand the best chance of seeing one.
The night before my planned visit, I slept little and when I did, I dreamt of Purple Emperors – this is what’s become of me, my waking and sleeping hours are filled with butterflies. I knew when I started this challenge that this sort of excitement and anticipation would be exactly what drove my desire to continue with it.
Stomach twisted in hope, I headed to the Heath. Once a favoured rendezvous point for highwaymen, Putney Heath is a distinct part of the better-known Wimbledon Common and together they consist of 1140 acres of scrubland, heathland, woodland, meadows, ponds and a windmill. My first stop was just near the back garden where one had been spotted a few days before but there was no sign any. After a quick chat with my informant over his garden fence, I headed towards one of his recommended hotspots, a relatively open area of the woodland where several paths converge, and a stand of goat willow can be found. Female Emperors lay their eggs on goat willow, also known as sallow, so Emperors can often be found in and around these trees. The spot had a regal feel about it and I was half expecting to see one any minute. Not too dissimilar in size and colour, a Red Admiral got me all of aflutter at one point but again there was no sign of his more spectacular cousin.
Onwards then to one of the other recommended spots, Kingsmere, the largest pond on the Commons. The area was buzzing with dragonflies and I got some good views of Purple Hairstreaks in some of the lower-growing oaks – right colour, wrong species. The pond and surrounds were teeming with life but for some reason it didn’t have the same magical air of expectancy of the previous spot so I decided to head back and try my luck there again.
Nearing an open area of the path, I spotted a butterfly fluttering under the branches of a beautiful, mature beech tree. It was large and I didn’t recognise it as any of the more familiar species. Cue heart racing. Several people were milling around near the base of the tree, and it fluttered up into some of the lower branches. Holding my breath, I tried to find it in my binoculars, desperately hoping it wouldn’t get spooked by the toddler wailing from the nearby buggy. Once I’d got it in my sights, there was no mistaking the striking pattern of His Majesty’s underwings, arguably as stunning as his purple-tinged upper sides.
Looking down regally on his royal subject, me, he then glided down to the ground and started gorging on a dog poo. That’s the thing with Purple Emperors, they have some rather disgusting habits and can often be seen sucking salts and minerals from mucky deposits. I squatted down to get a better look at his fetid feasting and was treated to several mesmerising minutes watching him coil and uncoil his bright yellow proboscis (tubular tongue) into various putrid piles.
Male Purple Emperor wings have a magical quality in that the iridescent purple sheen covering the upper side of them only reveals itself in certain lights and so, despite the dappled shade under the beech tree, every so often I would get a brilliant flash of violet as he flexed his wings. Once sated with salts he drifted back to the treetops and out of sight leaving me grinning from ear to ear.
I still have 7 boroughs to visit on the 33 Butterflies Challenge but as coincidence would have it, and very fittingly, the Purple Emperor was the 33rd butterfly species I’ve seen this summer.
Full list of species seen 16/7: Small white, Large White, Purple Emperor, Purple Hairstreak, Large Skipper, Small Skipper, Red Admiral, Comma, Meadow Brown, Ringlet, Holly Blue, Clouded Yellow, Speckled Wood.