check up on Southbya in Lydstep

On the way back from St Davids (long weekend camping) I decided to pop to Lydstep to check out Sams Southbya tophacea colony he had recorded back in 2012?  I am slowly visiting all the Welsh populations, just Barafundle Bay left. I had a quick scrabble up the cliff and after about 40 minutes I had identified a few very shrivelled up colonies. To say a few I mean three at best, none more than 10 cm in area and all on loose open ground of which there wasn't much (see general site photo). So good to confirm it is still there (SS 09150 97747).

Interesting that it was growing in the unconsolidated and quite loose 'scree' made up of fragments of limestone from the host bedrock (Carboniferous Pembroke Limestone Group) mixed together with clay and soil, rather than directly on more permanent tufa forming seepages (like the VOG populations). I could only find it on more open areas of ground, which were very limited.

The weather was gloriously dry, so I would hope to find more  if everything wasn't so shrivelled up, mind you, not sure id fancy climbing that cliff in the wet.

As usual I was armed with a totally underwhelming iphone4 for photos, so do 'enjoy'.

location on cliff

general view of site, with lots of Contoneaster and other ground cover..including Hannah busy getting a closer look. 

close up, Southbya on the unconsolidated material rather than direct on the bedrock. 

Colony of shrivelled up Sothbya tophacea  (I know another terrible photo, was checked with x10 hand lense)

New turlough ??

Reading Georges blog on his trip to the Alun Valley I remembered I had also come across a large area of Marchesinia mackaii (MacKays Pouncewort) on a wooded Carboniferous Limestone outcrop on the western margin of the Nedern Brook Wetland, nr Caldicot (ST 48259 89508).

Marchesinia mackaii...I think !

That in itself is perhaps not that interesting, however the site in question certainly is !

I’ll keep it short: The Nedern Brook Wetland, is quite unusual, it is for all intents and purposes a ‘turlough’, however I don’t really like using that name in Wales.  It is dry in the summer and in the winter groundwater flooding creates a lake 1.5km long and up to 2m deep (report being finalised for NRW as we speak).  As you will know this is a very rare habitat in the UK, only one site in Wales, Pant-y-llyn nr Crosshands, currently fits the description, and there are only three very small ones in Northern Ireland completing the UK habitat.

Nedern Brook Dry (with Egret in shot too!)

Nedern Brook full of water 

‘Why have I never heard of this site?’ I hear you cry….well good question, I really don’t know, and I am convinced it deserves a higher profile, if only for its hydrology.

Hydrologically the site fits the turlough description however I would love to find some of the bryos that are associated with this habitat, namely: Fontinalis antipyretica and Drepanocladus aduncus and others, across the margins where seasonal flooding occurs.  I had a trip to the site with Julian Woodman looking for water peppers but we didn’t really attack the bryos on the seasonally flooded margin.

If anyone finds themselves near Caldicot and fancies a look let me know!