Re: Asian Carp
"Asian carp" is sort of a catch-all: from what I've read today, they've only found grass carp successfully spawning in the Great Lakes- still not great, but not as bad as the other two- bighead and silver carp.
They (bigheads & silvers) subsist on plankton- the same stuff as forage fish and juvenile sportfish species. In the Mississippi River they compete with native species such as gizzard shad, which can in turn alter the rest of the food web.
However, they require moving water in order to spawn- the eggs must remain suspended in the water column for a substantial amount of time in order to hatch. Unlike the flowing Mississippi, asian carp in the Great Lakes will be limited by the number of streams where they can successfully spawn. Still not a great situation, but probably not as devastating as the effect of asian carp elsewhere.