Wednesday, 8 August 2018

Moth event at Wern Claypits Nature Reserve, near Arddleen

This was a joint moth-bat event with Montgomeryshire Wildlife Trust, and was the first time that MMG have trapped at this wetland site. The target species for the evening was wainscots - more of that later.

At 16 degrees C the evening was a little cooler than of late, but it was good to see 13 people enjoying the chance to locate both bats and moths. Tammy entertained an eager group, quizzing them on their bat knowledge, and then demonstrating the bat detector’s ability to pick up the high frequency calls used by bats, which are normally inaudible to humans. Here’s Tammy’s rundown of the evening’s bats:

“As we stood admiring the beautiful display from the white Frogbit flowers, carpeting the water’s surface in places, the first bats made an appearance. The Soprano Pipistrelle was probably the most numerous bat species, with almost constant activity all evening and great views of them flying and feeding against the gorgeous clear sky. Common Pipistrelle bats were also about, seeming to avoid directly competing with the Sopranos by flying around the tree tops, rather than over the water. Myotis bats were frequently picked up on the Anabat Walkabout bat detector; this is a group of five very similar bat species, which can be hard to distinguish. One of these species, that we had expected, was the Daubenton’s Bat, however none were seen during the evening and later analysis of the recorded calls was inconclusive. Some Myotis recordings were identified as either Whiskered or Brandt’s Bat, with over 80% likelihood.”

Meanwhile, the moth-ers were busy setting up 10 traps, with the ‘white sheet’ at base-camp, 2 Heath actinics,1x125W MV Robinson and 4 Skinner traps around the path which encircles the lagoons on the reserve.

Even before the traps were switched on, there were large numbers of Small China-mark to be seen above and amongst the vegetation in the water. Once the traps were up and running, it was the Brown China-mark which was particularly numerous - in fact it was the most common moth of the evening, with numbers probably in the hundreds. Before long, Beautiful China-mark had also been recorded, and it was interesting to learn that the larvae of this group feed below water level on aquatic plants.

As several of the group were new to 'mothing', they were particularly taken by the more colourful or unusual moths, and there were plenty to be seen, including Large Yellow Underwing, Iron Prominent, Gold Spot, Canary-shouldered Thorn and Svensson's Copper Underwing. But perhaps the most striking moth for many of us was a pristine Leopard Moth, which was photographed from every angle by several mothers eager to capture its bluish sheen, spotted furry thorax and seemingly translucent spotted wings. It was very accommodating, remaining on the white sheet for the rest of the evening. Douglas explained that its larvae overwinter for several years, in the stems of the trees on which they feed, eventually pupating under the bark.

The distinctive bright greenish yellow caterpillar of another species, Pale Tussock, was found on willow, and delighted the group with its four tufts of yellow hairs and the black bands between each segment, and a rather striking red tuft at the tail end.

As a car rally was due to pass the 'mothing' spot in the early hours of the morning, it was decided to pack up before any conflict of interests ensued - typically some of the 'best' moths turned up right at the end - a Lesser Cream Wave and (a suspected) Monochroa lutulentella - both specialists of damp habitats.

But as for our target group, only a tatty Smoky Wainscot decided to play ball.......................... another time maybe.

- Sue S.


  1. Sounds like you all had a good evening Sue - great to see a scarcely encountered species like the leopard Moth at one of our events.


  2. Thanks for the report, Sue!

    I'll sort the species list later in the year - it was around the 90 species mark in total. Definitely a site worth returning to I think.