27th July 2023 - the RiverCare team meet to undertake the monthly river sampling of the river Granta, by the ford. They found several Signal Crayfish and four small fish, including two Bullhead (aka Miller's Thumb) and what are possibly two Stone Loach. If so, the latter only live in very clean water, not tolerating even mildly polluted water, so that's good news.
Also good numbers of the larvae of both Blue-winged Olive and Olive (both types of Upwing flies) and those of Mayfly and Cranefly. Several Cased Caddisfly and Freshwater Shrimp were also found, as well as a Water Boatman.
Bullhead aka Miller's Thumb
Stone Loach (and small Olive larva)
Stone Loach, showing three pairs of barbels around the mouth
(and a Mayfly larva underneath)
Signal Crayfish
Signal Crayfish
Mayfly larva
Mayfly larvae
Mayfly larvae
Blue-winged Olive larvae
(note the wider 'skirt' around the gills towards the rear of the body)
Blue-winged Olive larva
Olive larva (lacking the wider 'skirt')
Olive larva
Water Boatman
Cased Caddisfly larva
Freshwater Shrimp, Gammarus
Pea Clam, or Fingernail Clam - note the extending foot
River Worm (left), and Cranefly larvae
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