Inky covered quite a few of them, I've mentioned a few more invasive plant species in a reply to her comment. I'll add one more animal species she missed - carp. A far more prolific breeder than any native fish, carp degrade the local waterways, out-compete everything for food, and thus far no predator or viral/bacterial agent has been discovered or developed that is hostile to that genus only, without attacking other fish. Calicivirus has decimated the feral rabbit population, prickly pear was brought under control by introducing its natural enemy, the cactoblastis moth. We've not yet been able to do anything about the carp - they're not even good eating.
This post was edited by Slartibartfast at October 8, 2020 2:23 PM MDT
Carp seem to be everywhere, but here in the Lake Erie area, they have been here so long they are considered a normal part of our ecology. I have eaten smoked carp. It is quite good.
They have torn down all the nice quaint houses and built three story McMansions with no lawns. They are far from pleasant when they're store owners and if you aren't Russian. they would just as soon you shopped elsewhere.
Loads and loads.. japanese knotweed is less of a problem than it used to be, rhododendron is still a problem in many areas, Indian balsam is a problem, many of the aquatic plants are invasive and choke rivers and streams. Non-native crayfish are a problem... and we even have foreign ladybirds that compete with and/or predate native species I believe.
inky 