Interview: Keeping Alien Invaders Out

  • Asian Carp is one species that is very dangerous to the Great Lakes ecosystem (Photo courtesy of the US Fish and Wildlife Service)

Nature never made a connection between the nation’s big rivers and the Great Lakes. But Chicago did. A canal was dug connecting the Mississippi River system – including the Missouri, the Ohio and all their tributaries – to all of the Great Lakes at a point on Lake Michigan. It opened up commercial shipping to the interior of the nation.
But it also opened up both bodies of waters to aquatic life you don’t want traveling back and forth. Invasive species such as the zebra mussel have traveled from one to the other. Asian Carp have already caused havoc in the Mississippi. Some biologists worry the Asian Carp will destroy the four-billion dollar fishing industry in the Great Lakes if it gets in. There’s an electric barrier in place, but some people don’t think that’s enough.
Joel Brammeier is with the environmental group Alliance for the Great Lakes. His group is proposing a barrier that will separate the Mississippi system from the Great Lakes completely, to stop those invasive species. He talked with Lester Graham about the barrier:

Transcript

Nature never made a connection between the nation’s big rivers and the Great Lakes. But Chicago did. A canal was dug connecting the Mississippi River system – including the Missouri, the Ohio and all their tributaries – to all of the Great Lakes at a point on Lake Michigan. It opened up commercial shipping to the interior of the nation. But it also opened up both bodies of waters to aquatic life you don’t want traveling back and forth. Invasive species such as the zebra mussel have traveled from one to the other. Asian Carp have already caused havoc in the Mississippi. Some biologists worry the Asian Carp will destroy the four-billion dollar fishing industry in the Great Lakes if it gets in. There’s an electric barrier in place, but some people don’t think that’s enough. Joel Brammeier is with the environmental group Alliance for the Great Lakes. His group is proposing a barrier that will separate the Mississippi system from the Great Lakes completely, to stop those invasive species. He talked with Lester Graham about the barrier:

Joel Brammeier: Well, ecological separation means no species moving between
the Mississippi River and the Great Lakes. When you consider the problem of
invasive species, unlike chemical pollution, which you can reduce to a certain
safe level, there is no safe level of invasive species. Once two get in, they can
reproduce, and the damage is done, and there’s no going back. So, an
ecological separation means stopping fish, and eggs, and other critters from
moving back and forth between the two systems.

Lester Graham: How do you do that when there’s so much commercial traffic
and recreational boating, and just the water flowing through?

Brammeier: Well, in our research, we found that tech fixes – electrical barriers,
sound barriers, blowing bubbles through the water to try and deter fish from
moving – those things can reduce the risk. But for invasive species, risk
reduction really isn’t enough – you need 100% protection. And to do that, we’re
probably looking at some physical barrier that prevents water and live organisms
from moving between those two great watersheds.

Graham: I can imagine the commercial shippers are not thrilled about that.

Brammeier: Well, I think it remains to be seen. Nobody’s quite sure where the
best place is to put a barrier. We discussed about half a dozen different
scenarios under which you could implement that kind of separation. The
Chicago waterway system does support about 25 million tons, give or take, a
year of commercial commodity traffic – and that’s a significant amount. The
reality is that most of that cargo is internal to the Chicago waterways. So, there
isn’t a huge exchange of cargo between the Chicago waterway and the Great
Lakes. And that’s a good thing. That means we have opportunities to actually
split the system back to the way it historically was, and at the same time, solve
our invasive species problem.

Graham: Now, we can see how that would benefit the environment, but how
would it affect the economy?

Brammeier: Well, again, going back to this issue of commercial navigation. If we
create a separation in this system that has a minimal impact on most of the cargo
in the Chicago waterway, we’re really talking about potentially a very small
impact. And, frankly, there’s an opportunity here to create a benefit for
commodity movements as well. A lot of the cargo transfer facilities on the south
side of Chicago are outmoded, outdated, and not competitive. And, any
investment in this kind of project that changed that and also allowed cargo to
move more efficiently and created new port facilities, could have that kind of
benefit, besides protecting the Great Lakes from invasive species.

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