Thursday 31 May 2012

Monitoring spotted rock rose (Tuberaria guttata)

Our field visit yesterday included representatives from the Countryside Council for Wales, North Wales Wildlife Trust, RSPB and BSBI as well as interested local botanists. The spotted rock rose (Tuberaria guttata) is Anglesey's county flower and very restricted on a few sites (it is also found in Wales on one site on the Lleyn peninsula, and a few scattered sites in Ireland and the Channel Isles).  Organisations like the RSPB and the Wildlife Trust, which own some of the sites, have been carrying out regular counts for some years, while other sites in private ownership are less often visited. While meeting on a site, we aimed to carry out some survey and also agree a consistent method to be applied at all the sites, by a range of different people. The discussion was fairly wide-ranging including questions of whether counting colonies or populations is useful (it probably depends upon the number - with large numbers estimates are necessary); whether tiny plants should be counted equally with large ones, and how to draw a sketch map or take a useful photograph. 
Discussion around a patch of Tuberaria
The management and monitoring of an annual species which can be subject to large natural fluctuations in population size causes some difficulties. As does the counting. In the photograph below the two plants with flowers on are obvious. What about the 30+ other plants? All of these will also produce flowers although each flower only lasts a few hours. Around lunch time one can watch as a flower suddenly loses all its petals within seconds.
Two flowers, and over 30 non-flowering plants
 Another Anglesey speciality was Viola lactea - pale dog violet - identified in Anglesey by its truncate to cuneate leaf bases (never cordate as in Viola riviniana).
Pale dog-violet
Viola lactea

Spignel in Merionethshire

I went  with Sarah Stille to monitor a population of Meum athamanticum - spignel. This site has been 
Flowering head with pink-tinged petals 

known for a while and the population seems to be growing happily around the margins of a field of fertilised and grazed grassland. Perhaps it favours the well-drained banks, or could it be that there is less nutrient enrichment around these margins (the farmer was spreading muck on the day that we visited, but little reached the Meum areas). The farmer thought we were a month early but there were plenty in flower at some patches - and even the vegetative plants were a distinctive yellowish green and easily distinguished from the grass. 

Looking at other photos on the web, however, I now wonder if these are rather small specimens - certainly compared to John Crellin's photos from Ben Lawers, on his site 

Sarah is also starting a blog to share her activities in Merionethshire (VC48). Last week there was a field trip to Cwm Hesgyn, which may have been relatively species-poor but still turned up some new species for the hectad. 
Dense flowering patches of Meum athamanticum
Another patch with few flowers (we should have gone later)

Antennaria dioica - sex ratios

Female flower heads
Male flower heads
Just over a week ago I visited one of Anglesey's sites for Antennaria dioica - mountain everlasting. I went with Ian Bonner, the vice-county recorder, who has been recording the sex of the flowers that he counts there. He said that at that point all the populations he had visited had been exclusively female. However, at this population on Cors Goch SSSI we found roughly 50% of each sex. Hopefully this is shown in my slightly blurry pictures.

The larger picture shows a number of flower heads and also the leaves with their distinctive silver felted undersides.