Hi
morrisdancer.
Our fishery, near Sheffield, is run on pretty much the same lines as yours.
The larger fish here too tend to "disappear" shortly after stocking but then there are depths of up to 30ft for them to go into and no-one sets out to fish for them.
Larger fish, particularly browns, do seem to make an appearance around October time. Something seems to trigger them into gorging on fry before the onset of winter. I should think that's why they fell to white lures.
I suspect that, during the warmer months, they may feed exclusively at night - but it's only a theory.
I should like to see some of the
numbers men demonstrate their
skills on our tree-lined, 7½ acre reservoir when the fish have been feeding exclusively on greenfly for a month - that would be educational