Eric Love: for E. canadensis to become established, "evil aquarists" don't have to empty tanks of it into nearby marshes.  All it requires is flushing pieces of it down a toilet when cleaning a tank.  "Invasive species" refers exclusively to those deliberately or inadvertently introduced outside their natural ranges via human agency.

The problem with this is that naturally-occurring biota evolve together over thousands or millions of years, struggling to eat and not be eaten, to where said biota establishes mutually sustainable numbers (which usually fluctuate cyclically).  In a stable system like this the prey don't overpopulate and eliminate their food supply and starve, and the predators don't overpopulate, eradicate their prey and then starve (or succumb to disease outbreaks).

Introduction of invasive species destabilizes such systems.  The more invasives introduced, the longer the system takes to restabilize and the more native species become extinct.  Research chestnut blight.

Labels: moderation: safe