I joined a botanical webinar a few weeks ago in which the presenter discussed the kinds of people who get involved in botanical recording. There are of course the professionals, working for ecological consultancies, charities (such as the Wildlife Trusts), University research departments or government agencies.

These people know their stuff. Then there are those you might call amateurs, but the presenter preferred to term “unpaid professionals”. His point was that a large amount of the work of botanical recording depends on the voluntary contribution of a host of people who have never been paid for an hour of their time, but whose expertise may stand comparison with, or even exceed, that of their paid professional peers. 

This is not just true of botany. In 2024, I had the great pleasure to welcome a group of unpaid professionals to Newdigate Brickworks Nature Reserve in the shape of members of the Surrey Moth Group. Across five separate sessions between mid-May and the start of October, accompanied by one genuine non-professional of almost no useful knowledge at all (me), they came to the Reserve with their generators and their light traps and recorded the moths of Newdigate.

Their knowledge is astonishing. It’s not easy, this moth identification business: there are in the British Isles around 870 “macro” moths – the (mostly) bigger ones – and roughly 1,670  “micro” moths – the (mostly) smaller ones. On a warm evening in summer, there will be dozens of insects fluttering around the light, in the surrounding foliage, crawling over the light trap, hiding among the egg boxes within it.

Near instant identification of most of them is needed to have half a chance of making a complete record of what is there. In comparison to the butterflies (59 UK species), you can see there’s a mountain to climb to acquire the required expertise. Which is not to say the Group restricts itself to moths alone: they also recorded caddisflies, crane flies and parasitic wasps; even a Pondweed Leafhopper (see this blog) and some male glow worms.

Across the five visits, I estimate the Group as a whole contributed more than 65 hours of work on-site and more time off-site to produce composite lists and confirm a few identifications after each visit. On two occasions it was just me and Paul Wheeler, who is my main contact with the Group and its chief organiser, running two light traps off a single generator.

On a lovely warm evening in late July, four members of the Group attended and ran eleven light traps off four generators. That was some evening, the last traps packed-up only around 4am, and over three hundred species of insect recorded in one night.

Over the summer as a whole, what this significant and impressive effort has given us is the first detailed record of moth species at Newdigate Brickworks ever undertaken: a hugely valuable dataset not just for the Reserve, but for the county and wider region.

So, what was found?

First, the headline species counts: 420 species of moth and 1 butterfly (a Painted Lady, on a night out), 21 caddisflies, 20 craneflies and 8 other fly species, 5 beetles, 3 true bugs and 7 or more parasitic wasps – some of the wasps have been sent for identification to the Nocturnal Parasitic Wasps Project at the Natural History Museum.

All in all, the Group tell me that this record identifies Newdigate as one of the very best sites for moths in Surrey and significant in a wider context too.

I cannot in any way do justice to this range of moths in a single blog, but I have picked out a few from each session with guidance from the Group: some for their scarcity, some because they are indicative of particular habitat features at Newdigate, and some just because they look fantastic.

May 14th

Among 53 species recorded in May was the nationally scarce Mocha, which the 2021 State of Britain’s Larger Moths report also lists as one of the thirty macro moth species with greatest range contraction. This moth is, I hope you agree, a beauty. Its larvae feed on Field Maple and it favours long-established woodland and hedgerows. We found it on the Pylon Ride on the west side, where a corridor for electricity pylons cuts through the trees. The north-west corner of the Reserve here includes a small area of ancient woodland. Woodland rides can be havens for invertebrates and ours seems to be no exception: it proved a treasure trove for moth species throughout the summer. In daylight, it is also pretty good for butterflies.

Here are a few more recorded in May to feast the eye:

June 24th

The range of moth species flying to light changes over the course of the year as many moths have short lives as adults. Six weeks is a long time in their world, and it was nearly all-change by 24 June. Of a total of 149 species recorded, 136 were new to the list from May. It was a pretty good haul, but could perhaps have been even better: while the evening started warmly enough (good for moths), it cooled significantly towards the end of the session (not so good), in particular for the traps situated out in the open grassland. The treasure was again in the woods and the Ride. I’ve mentioned the Brussels Lace in a previous blog on lichens (see here): we think this record is the first in Surrey for 30 years and only the second in more than 70 years.

Another to highlight this month was the White-line Snout, nationally scarce and also rare in Surrey. As far as we can tell, this Newdigate record is only the second in the county in ten years. It is also not a well-studied insect: known at least to favour damp woodland, its foodplants in the wild are unrecorded.

July 30th

At the July session, the weather was near-perfect: it stayed warm and still till dawn. 291 species of moth were recorded (an exceptional number for one night at any site) of which 202 had not been recorded in either May or June. Among a large number of micro moths, we had only the 3^rd or 4^th Surrey record of the rather gorgeous Kent Tubic, which as its name indicates has to date been mostly found in Kent. It is another woodland species and its larvae feed on lichens on tree trunks.

Rarer still in Surrey is the Heath Marble. Prior to this Newdigate record, it had been presumed extinct in the county since at least 2012. It is a moth of rough grassland and scrub, feeding on species of Woundwort and Mint. Newdigate has two Woundworts – masses of Hedge Woundwort (mainly in the woods) and at least some Marsh. There is also plenty of Water Mint, including on the edges of the grassland.

Below are a few more from the July list:

September 2nd

Moth abundance is in decline by September as the summer draws towards its close. We recorded 54 species at this session of which 16 were new to the list so far. It might have been better, but the weather was unkind: intermittent mizzle turned to proper rain a bit after midnight and we wrapped-up by 1am. All the same, we recorded a couple of nationally threatened species.

The Oak Lutestring showed a mean 10-year rate of decline exceeding 50% in the 2021 State of Britain’s Larger Moths report. It is classed Endangered on the 2019 Red List. We found it twice at Newdigate, once on the Ride and once at a light trap in the grassland. It is characteristically a species of long-established oak woodland and its larvae feed on Oak.

October 2nd

The last session of the year gave us 31 species and 13new additions to the Newdigate 2024 list. The traps on the Pylon Ride and near the North Lake produced some decent records, but the grassland trap attracted very few moths. Among those near the Lake was the Figure of Eight moth. This is classed as Endangered on the 2019 Red Listbecause of sharp decline in population. It can be found in scrubby habitat and old hedgerows in which Blackthorn, Hawthorn, and fruit trees such as Crab Apple, Pear and Plum are also found.

A lake-side trap also brought-in the nationally scarce (and rare in Surrey) Brown Alder Bell micro moth. As its name suggests, Alder is its larval foodplant and it favours the banks of rivers, streams and lakes where Alder grows. Newdigate has a lot of Alder around both its lakes and also in some of the surrounding woodland where it floods in winter.

Here are a couple more from October I thought were particularly striking:

Well, I hope that was an engaging tour of the moths of Newdigate, even if only a fraction of all those recorded by the Surrey Moth Group. They may be back again for a session or two in 2025 and are very welcome. Huge thanks to them for the time they have committed to Newdigate and the invaluable record of its moths and other insects they have produced.

Stephen Woodcock

Voluntary Warden, Newdigate Brickworks