Here’s a scenario. You catch a brook trout in a seemingly clear
and clean stream. There is no industry to speak of, but the
stream is open to Great Lakes salmon that come up and spawn and
die in the fall. What are the chances of that brook trout being
contaminated with nasty chemicals? The answer is they just might
be, according to a story in Science Daily today that reports on
University of Notre Dame research that found that the unintended
consequences of allowing Great Lakes migratory fish to pass
upstream can be a transfer of the contamination from salmon to
say, a brook trout – and your dinner. Salmon accumulate a
variety of toxic chemicals during their stay in the Great Lakes,
particularly near big urban centers. Those chemicals are left
behind upstream in both their rotting bodies after death and in
their eggs which brook trout eat. As Michigan moves ahead with
dam removal projects on Great Lake tributaries like the Boardman
River, this is an issue that will come into ever-sharper focus.
And it should.