Marsh Fritillary Survey in Ceredigion

A few days were spent at Caeau Llety Cybi pulling bracken from the grassland and cutting brambles back. The good news is that the bracken does seem to be reducing year after year. The sun even came out and we managed to do a quick butterfly survey for the Butterfly Conservation Big Butterfly Count.

All the paths at Coed Maidie B Goddard have been cleared of overhanging vegetation and half the butterfly meadow has been cut and cleared with some willows being cut back around the edges. The bees have had a successful year in this meadow, though they don’t seem too keen to have the vegetation cut down!

Marsh Frittilary larval web by E Foot

Marsh Fritillary larval web by E Foot

At Coed Penglanowen the woodland glade was also cut and cleared to keep the scrub from encroaching. This seemed to be a much quicker job than in previous years so either we are all fitter or the number of brambles in the meadow is decreasing. We are not trying to eradicate brambles entirely as they are good habitat in the right place, large patches are left around the edges.
Our joint work party was in Pembrokeshire this month. We spent the day coppicing blackthorn at West Williamston where brown hairstreaks are found. They lay their eggs on young blackthorn. We had a big fire to dispose of the cuttings.

The annual marsh fritillary survey was completed at Rhos Pil Bach. 3 compartments were surveyed using Butterfly Conservation’s transect method. Unfortunately, though the habitat looked suitable, only one larval web was found, continuing the low trend from the previous few years. The larvae found were quite small, about 4mm, so we may have been a bit early for others. The voluntary warden is going to keep an eye out for more in the next few weeks.

It was a more successful story at Rhos Fullbrook where marsh fritillaries have not been recorded since the 1990s. After hearing that adults were seen at Cors Caron last year I decided that a survey should be completed at our reserve which is a short distance away. Feeling not particularly hopeful we started our survey near the main entrance and zig-zagged our way across the two wet meadows. There was plenty of scabious, the larval food plant, around but I was still very surprised to find a web with larvae in near the far end of the first field on a slightly raised area. Feeling buoyed by our success we continued but found no more webs in that field. With hope fading we started the second field and before long had found another web! The first of many as it turned out. All together we found 20 occupied webs and 2 empty ones! Not bad for a site that hasn’t had them recorded on for over a decade.

Thank you very much to everyone who has helped this month. If you would like to volunteer with us in Ceredigion there are work parties twice a week out on the reserves, year round, contact Em on 07980932332 or e.foot@welshwildlife.org or to find out more about Ceredigion reserves visit: www.welshwildlife.org/reservesCeredigion_en.link