A day in the Broads

A very early start to maximise time in the field saw me at Strumpshaw Fen RSPB reserve shortly after 7am. The purpose of the trip was to search for the larval cases of the UK BAP Priority moth Coleophora hydrolapathella. The larva feeds on Water Dock and the cases are fixed to the dead stems for pupation. There are no recent records from the Mid Yare Valley where Strumpshaw Fen is situated but as I was passing, I thought it worth a look. I walked all the way around the Fen Trail and the only reward was my first Swift of the year (what does that say about the Swift situation in Hampshire). I found very little Water Dock until the very end of the trail but there is a vast area of habitat that is not accessible to visitors.

Next stop was Alderfen Broad, a small Norfolk Wildlife Trust reserve where hydrolapathella was recorded in about 2000. I walked round the nature trail and eventually found a single larval case of the target species.

It was interesting to see that an area where the vegetation was cut in front of a viewing screen had abundant Water Dock so the cutting of further small areas around the Broad may well benefit the moth.

Walking back through the shelter of the wood and with occasional sunshine, I saw my first damselflies of the year and my first small swarm of the longhorn moth Adela reaumurella plus a reasonable selection of hoverflies. I was also pleased to see large amounts of Climbing Corydalis - ok so it's not rare but it was new for me!

Around the site were notices explaining about the large scale clearance of the non-native Red-berried Elder Sambuscus ramosus that had taken place. I could see no evidence of any clearance and the shrub was abundant so clearly something had gone wrong but it was of interest in that I had never even heard of this species, let alone come across it as a significant invasive.

My final port of call was another NWT reserve at Martham Broad. I could find no Water Dock here but the previous record of the moth was of an adult, rather than the larval case, so it may have wandered from the vast inaccessible areas of the reserve. By now the bitter wind had really picked up and all I saw of any note were a couple of Marsh Harriers quartering the marsh.