Having spent several weeks tracking large Starling flocks flying over my house every morning, I finally got out on a calm evening to pinpoint the roost site. The birds are roosting in a small reedbed south east of Parys Mountain, next to a small windfarm. X marks the spot! Grid Ref. SH449897
This evening I estimated the numbers at between 75 and 100,000 birds coming into roost. The small reedbed slowly turned black as several large flocks flew straight into roost (there was no murmuration though). Several flocks of sheep and horses were startled by the huge numbers landing in the fields nearby.
The roost can be seen well, but distantly, from Parys Mountain, but there are several footpaths on the map which could be explored. Not the biggest roost I've seen on the island but pretty spectacular, and I'm not aware of them using this site before.