I spent yesterday afternoon visiting my old friend Tom and his buddy
Pete.
Tom is 68 and Pete 87. These old Ennis Montana old timers are among
the oldest (former) Montana fishing guides still kicking around. Tom
and Pete
told me stories about fishing the Missouri below Tosten dam in the
late 1960s,
when mayfly hatches were so thick the surface of the river looked like
it had
the whirlies.

Today, some 40 odd years later, the hatches there are nearly non-
existent.
What's made the difference? Tom said he thinks it's agricultural
pesticides.
The Missouri down near Wolf Creek still has some good hatches
(although nothing
like they used to be) but that water comes out of three dam, deep
water
filtering system. The Missouri in the Tosten area shallow, containing
undiluted
runnoff from millions of acres of fields, all sprayed regularly with
an every
increasing diversity of noxious chemicals.

Tom said he'd asked various Fish and Game biologists about his theory.
They all said "Sure, we think that too. But we have no baseline data
from
50 years ago, and therefore no way to prove the allegation."

Still, as the old timers can tell you, the hatches are nothing like
they used to be.

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