Okay, I'll be clear: I completely agree that this is a problem, caused by people, and has potential for becoming more and more of an issue as time passes. The genie is out of the bottle, and there is no putting him back in.
But, I'm going to play Devil's Advocate here for a second. I have spent my entire life listening to every new-and-improved "ecological disaster" that is supposedly looming on the horizon, each one more capable than the last of destroying life as we know it. Each of these introduced species is the next eco-killer, which will decimate native populations and upset the balance of nature. Each one is poised to spell doom. You know what? It never seems to happen that way.
When Zebra Mussels arrived, they were going to outcompete native fish fry for micro-food in the water column. They were going to filter out all the planktonic organisms, starving out the hatchling fish and clarifying the water which would lead to choking algae problems. Well...the water is much clearer in many areas than it was before they arrived...but fish populations seem healthier than ever. Fishing is better. Aquatic plants grow more luxuriously and in deeper water than they used to grow...or maybe it would be more accurate to say that they grow like they used to before we clouded and polluted the water in the first place. Yep, the mussels cause some problems for industry, by clogging pipes and such...and of course some egghead statistician comes up with a figure of $650,000,000,000,000.00 that they are supposedly costing us, so I guess they are destroying the economy as well as the ecology...but the horror stories never seemed to come to fruition.
Purple Loosestrife was an escapee from people's gardens a few decades back. It was destined to wipe out native wetland vegetation. Vast tracts of swampland would be overrun with a mono-specific culture of loosestrife, which would support no native insects, birds and other animals. The wetlands would be silent wastelands...lots of pretty purple flowers but nothing else. When loosestrife first arrived on my rural acreage, I slaved for several summers pulling it out by the handful, burning it with an agricultural flamethrower, cutting with a bushhog and generally waging war on the stuff to no avail. Three summers after it arrived, I had acres of the stuff and I was worried. Would I lose the wonderful wetland ecologies that I so enjoyed watching and admiring? Nope! Two summers further down the road, and the loosestrife was reduced to almost nothing. It wasn't anything I did... I had already given up the fight...but it just died back to a small, steady population and stayed that way for the remainder of the decade, until I moved away. It was just like so many other introduced species; it rapidly spread, reached a peak, and then died back to a much lower, more stable level.
Invasives must be discouraged, no doubt about it. There need to be controls in place to prevent unwanted introductions, because...you never know...the next one might be the planet-killer! I continue to eradicate House Sparrows and Starlings when they appear in my birdhouses, I am ruthless when it comes to killing non-natives when I can do so. But...sorry, I just can't panic about them anymore. I've been sold a bill of goods too many times by hand-wringing, doom-and-gloom environmentalist talking heads; I just don't believe them any more.
Anybody on MFK has to be very careful about getting too shrill regarding the horrors of introduced species. We pay big money to have species collected around the globe, or bred in captivity, and then we gleefully bring them home to keep them as pets. Accidents happen; worse yet, the pandemic...not the Covid-19 one, I am referring to the Stupidity Plague that never slows down and has no vaccine...results in critters constantly being intentionally released, or just casually thrown out, and then establishing themselves. We are probably the biggest contributors to the problem. We can't sit on the porches of our glass houses and expect to throw stones at other people.
Dang...nothing like a hot summer day, a cold beer and a good rant to get the juices flowing...