Left: salting 2 km wide on Dee Estuary, Cheshire.
Finding the right moisture conditions and tidal zone for Assiminea grayana is difficult on wide saltings in the mosaic of different levels and channels.
Right: narrow salting confined by levee along tributary creek of the Dee in Flintshire, Wales. Finding the right tidal zone for A grayana along the foot (1) of the levee was not difficult. A sample here of sieved substrate had c. 8000 A. grayana /m².