Norfolk bound

More catching up. In early September I called in to the New Forest on my way back from Dorset to twitch one of the Forest's speciality plants; Small Fleabane. It turned out that the best site for the plant was a site that I had walked round during a winter survey for the BTO's bird atlas and I'd thought at the time how awfully overgrazed - indeed trashed - it was. Well that's just what Small Fleabane needs, further evidence if it were needed that it is dangerous to assess the value of a site without considering all taxonomic groups.

In early September I went to Norfolk for a couple of days. The main purpose of the visit was to meet up with an RSPB researcher who is looking at Redshank breeding on saltmarshes in East Anglia. My job was to show him how to look for the larvae of the UK Biodiversity Action Plan moth Scarce Pug so that he could keep an eye open for it during his work. Scarce Pug larvae feed on Sea Wormwood and in recent years it has only been found on the NW Norfolk coast and at one site in Lincolnshire. The larvae are quite well camouflaged and when you find one you often notice several others in the same area that you completely overlooked.

We found good numbers of larvae at both sites visited and hopefully the RSPB researcher will extend our knowledge of known sites. Whilst surveying for Scarce Pug I always keep an eye open for the larval cases of the Nationally Scarce Coleophora artemisiella which is found on Sea Wormwood at the same time. Normally I find C. artemisiella larvae in much greater numbers than Scarce Pug but this year was the exact opposite. Presumably the earlier flight period of adult artemisiella fell before the weather improved this summer and resulted in low productivity.

Whilst surveying at Titchwell RSPB reserve I saw Common, Lax-flowered, Rock and Matted Sea-Lavenders within a few metres of each other which was very useful for sussing out the differences. The latter two species were both new to me and Matted Sea-Lavender is only found in Norfolk and Lincolnshire.

Matted Sea-Lavender

There is a great swath of Prickly Saltwort along the seaward side of the dunes at Titchwell which I don't remember seeing before. It was probably there all along but overlooked due to my botanical ineptitude!

Prickly Saltwort is the larval foodplant of the Nationally Scarce pyralid moth Gymnancyla canella and sure enough there were loads of larval spinnings (the larvae feed within the shoot in the early stages so the spinnings are the only evidence of their presence).

Potentially of more interest were several Noctuid moth larvae that were feeding on the plants. The only Noctuid that is recording on this foodplant in Britain is Sand Dart and it clearly was that - apart from anything else, Sand Dart feeds on the roots!

Consultation with a couple of experts has come up with the suggestion of Bordered Straw although neither were sure. If they are Bordered Straw then it would be a previously unknown foodplant. I now have a pupa in my kitchen so hopefully I'll find out soon!

That evening I ran a moth trap in the Brecks. It was too late in the year to get any of the Brecks specialities that I've not seen before but it was a productive night, the highlights being 3 Lunar Yellow Underwing and several Square-spotted Clay. The main reason for visiting the Brecks was to see some excellent work that a colleague has been doing to create bare ground to encourage rare, moths, plants, etc. It wasn't the best time of year to look at the sites but I did see Spanish Catchfly in poor light on the first evening. When I returned the next day to photograph it, I couldn't find any! One of the larger experimental plots had three pairs of Stone Curlews nesting on it this year. Hopefully I'll get the chance to revisit next summer.