Ecological observations on the fungal colonization of fish by Saprolegniaceae in Windermere.
The colonization of clean (apparently uninfected), dead salmonid fish by Saprolegniaceae was studied both in the laboratory and in Windermere. Colonization proceeded in 2 stages in water: initially there was superficial mycelium, which was easily removed, and later there was a deeper penetration into the epidermis and dermis. There was evidence that colonization could occur as an intimately mixed mosaic of different Saprolegniaceae. Live char and other salmonids were normally colonized only by Saprolegnia diclina. This specificity broke down when there was colonization of dead tissue on a live char. At post-mortem, salmonid fish killed by S. diclina did not attract other Saprolegniaceae subsequently and explanations for this are proposed.