Woodwalton Fen National Nature Reserve

Having spent a morning photographing Marbled White butterflies and Six-spot Burnet, Brassy Longhorn, and Burnet Companion moths on Trumpington Meadows near Cambridge I was inspired to travel slightly further afield to see if I could find any more interesting species of Lepidoptera. RSPB Hope Farm in Knapwell I remember had been productive on their pre-lockdown open days a few years ago and I remembered they had a wild patch of setaside.

Purple Emperor showing yellow proboscis

Purple Hairstreak

Brassy Longhorn

The farm and reserve are not strictly open to the public at any time other than their open days, but it’s criss-crossed by public footpaths, so you can see some of the site if you’re discrete and don’t stray into the non-public areas. While there were plenty of Meadow Brown, Six-spot Burnet, Whites, and skippers on “wild” margins, unfortunately the wild area now has a crop and so any chance of a range of Lepidoptera beyond the obvious was not going to happen.

Marbled White

So, I hopped over to Overhall Grove, a small woodland not far from Hope Farm. It’s a bluebell wood in spring and also has the relatively Oxslip ( a hybrid flower formed by the fusion of cowslip and primrose). I was too late for those, of course, but I did bump into a couple – Nick & Stella Laughton – with cameras and scopes and binoculars who were staring at the top of an ash tree. Turns out the tree was host to White Letter Hairstreak butterfly. They were very friendly and full of ideas on where else I might see other butterflies, namely Woodwalton Fen National Nature Reserve and the Newmarket “July Racecourse” end of our local Devil’s Dyke.

UPDATE: I bumped into Nick and Stella at Brampton Wood just after the Black Hairstreaks emerged in mid-June 2023.

Purple Emperor in flight

I took the trip to Woodwalten passing an antivivisection encampment on the way and ploughed on through to the Rothschild Bungalow. The oak trees on this site surrounding the bungalow are host to Purple Hairstreak (of which I saw at least a couple of dozen) and Purple Emperor (again maybe a dozen. One of the Purple Emperors had a perch high up in an oak on a prominent bough and would launch itself at any rival Emperors that flew too close. Indeed, it launched itself and saw off quite a few Emperor dragonflies too while I watched.

Burnet Companion at RSPB Hope Farm

Devils’ Dyke was for another morning, this time with Mrs Sciencebase. Stepping out, we spotted a pristine (presumably newly emerged) Painted Lady (not many around this year) and then a host of Chalk Hill Blues, dozens and dozens, perhaps hundreds spanning a stretch of a couple of kilometres that we walked that morning. Also many dozens of Marbled White and an occasional Six-spot Burnet. Another couple spotted a Dingy Skipper, a species I’ve never wittingly seen, but we may have seen it that morning.

Painted Lady

The Pyramidal Orchids were prominent but the much less common Lizard Orchids were past their best and we didn’t see those in bloom.

Six-spot Burnet on Field Scabious

Another species that Stella and Neil had mentioned as being at Devil’s Dyke as well as the Chalkhills was hopefully going to be Dark Green Fritillary. We passed lots of other walkers who hadn’t seen any, but then before we know it, it’s noon and the Frits suddenly appear, perhaps half a dozen or so scattered along the Dyke and being chased by the Chalkhills.

Chalkhill Blue – Male (Left) and female “in copulo”

A second visit to Woodwalton earlier in the day when the Purple Emperors were likely to be feeding on or near the ground was productive and I got snaps of that activity as well as a few better shots of the Purple Hairstreak.

Dark Green Fritillary

So, having perhaps seen fewer than 30 species of butterfly in all my 50+ years, I suddenly “ticked” another five species in the space of a week – White Letter Hairstreak, Purple Hairstreak, Purple Emperors, Chalkhill Blue, Dark Green Fritillary. Earlier in the year I’d seen Green Hairstreak at Les King Wood and last year Silver-washed Fritillary and Clouded Yellow at Waresley Wood. I have to confess I’d seen SWF in Dorset and CY in Greece in 2019), but not seen them locally until 2020.

Purple Emperor
Green Hairstreak
European Peacock