A preventative measure used by ships is supposed to stop tiny foreign aquatic animals from invading the Great Lakes. But a new study finds it doesn’t always work on their eggs. The Great Lakes Radio Consortium’s Lester Graham reports:
Transcript
A preventative measure used by ships is supposed to stop tiny foreign
aquatic animals from invading the Great Lakes. But a new study finds
it doesn’t always work on their eggs. The Great Lakes Radio
Consortium’s Lester Graham reports:
Ocean-going ships from foreign ports are supposed to swap out ballast
water while at sea. The ocean’s salt water flushes out or kills many
of the tiny invertebrate animals called zooplankton. But Derrick Gray
at the University of Windsor’s Great Lakes Institute for Environmental
Research says the higher salinity does not kill many zooplankton
species’
eggs…
“This is important because although ships exchange their tanks in
mid-ocean, if this doesn’t have an effect on the eggs, that means there
could be live organisms introduced into the Great Lakes.”
Gray says the concern is that more exotic zooplankton will out-compete
native zooplankton… a major
source of food for fish. That could hurt Great Lakes fish populations.
For the Great Lakes Radio Consortium, this is Lester Graham.