How to stop an invasion of the easiest fish in the world to catch

[News]

The last hope for natural control of silver carp in the Great Lakes was dashed when four invasive carp were found in a tributary of Lake Erie. If high-tech hardware won't work, maybe it's time to find out if some stone-age know-how can get the carp out.

More...

[SeaCatMich]

The problem with trying to control the carp through netting is that they are very difficult to net and from what I have read, it is especially with trawl nets. Trap nets or gill nets might work better but in my opinion we don't need more of nets the lakes.

I still don't understand why the rivers where they are so high in population are not just poisoned and then desirable species reintroduced. If 95% of the fish in those rivers are the carp, there isn't much other fish life to protect.

Apparently the carp are having trouble in many waters in their native range in Asia. Assuming the cause of the demise in Asia is not pollution (which could easily be) then why can't those same conditions be used here to eliminate/control them?