"Peter Charles" wrote in message
...


Excellent point George, hadn't considered that simple traffic would
cause a shift but it could have an effect. I know that Grand River
dinks become very tolerant of wading fishermen but you rarely see a
larger fish actively feeding close to a human.

Probably has a lot to do with options. There are many places where
fish simply cannot entirely escape human presence. Those familiar
with Penns in May will recognize it as a pretty good example. Where
they CAN escape, the bigger fish will naturally take up the best lies
in less trafficked parts of the stream, driving out what smaller fish
were already there. Oddly, this may actually be beneficial for the
smaller fish. Given a choice between human interference and the jaws
of concentrated cannibals up or down stream, those who opt for the
former may enhance their chances for survival. Then too, a small fish
probably does better competing against others more or less its own
size.....even against many others.....than against a smaller number of
larger competitors.

Wolfgang