Invaded Waters

The Great Lakes have become a giant outdoor biology experiment -- with no one in charge.

In the space of a few decades, an evolutionary snap of the fingers, vast populations of foreign fish, mussels and other creatures have invaded and damaged irreversibly an ecological design that took thousands of years to evolve.

These unwanted guests in the largest freshwater system on the face of Earth have muscled out native species, killed thousands of loons and other migrating birds, devoured food resources, clogged water-intake pipes and begun to spill into many of North America's premier interior lakes and rivers.

Many scientists say the invaders are a worse problem than the industrial contamination that fouled the Great Lakes in the 1960s.


http://www.startribune.com/lakes/

The link is to a page indexing a series of interesting (and depressing) articles on invasive species in the Great Lakes.

I'm reminded of the gypsy moth invasion, which had people worried about the devastation they would cause in north america. To my knowledge, this threat never fully materialized. I have a notion that the local wildlife adapted to the presence of the gypsy moth. Birds learned to eat them, I'm guessing. Either way, the ecosystem appears to have adjusted itself, quite rapidly.

Maybe I'm succumbing to the soft bigotry of low expectations, but I'll go out on a limb and predict that the great lakes ecosystems will reach an equilibrium, and the magnitude of damage will be limited.

(How's that for armchair ecology)

You are right, given time the ecology will work out a balance. However, that amount of time is greater than most humans patience allows. We want things now. We can't even wait for "in our lifetime." The Great Lakes will take thousands of years to work out a balance with the current invaders, and that assumes we don't introduce yet more foreign species.

I think the longer term view is that humans will act as transport vectors for all of the worlds most virile species, with the result that the global life forms will become much less diverse. And our observations demonstrate that when diversity is reduced, the dominant life forms get struck by plagues and die off, then regrow to die off yet again, in a reducing cycle that eventually, over many thousands of years, results in a new equilibrium.

Re: Gypsy Moths: They are still a real problem. Some states have tried to halt their advance, with limited success. Basically they can hold infestations off for an extra year or two, but then are reduced to damage control, as the moths always get past defenses.

for better or worse.

What have you heard about gypsy moths? I've heard almost nothing about them since the 80s. Just based on walking around in NY and PA, I haven't noticed much impact. Clearly, they're out there. There's no way to get rid of them.

I've a friend who's done research on them, and whose job it is to help control them. Says that the east coast is plain infested, and that they have expanded past the Great Lakes now. In the process they've surprised those who track them by being able to fly across larger bodies of water than previously thought. Also says that the damage done isn't generally obvious from the ground, unless you know what to look for. However from the air, especially from a low flying plane or helicopter, the damage is much more apparent.

I think control measures include pesticides, pheromones to confuse mating behaviors, releases of large numbers of moths bred as neutered, and the release of predator species. All have been tried, but all just delay, rather than halt, the advance.

If you want/need more detail I can probably get it for you.

I have no need for more info, it's purely idle curiosity. I'd be interested to hear what your friend thinks about the possible impact of gypsy moth infestation will be, over time.

We had a multi-year gypsy moth infestation a few years ago. It was fairly widespread here in North Jersey. The damage is very evident...mountainsides that don't get green because all the trees died.

The problem was that it was a multi-year attack compounded by drought which killed the beetles that eat the moth larvae. The gypsy's are pretty much gone for now but they'll be back.

The ecosystem is adapting but it is a long process. There are so many other stresses which worsen any one problem.

Bottom line is invasives are a done deal. There is no stopping them. The number of invasive plant species is astounding and the impact in some areas is overwhelming.

they do not LEARN the damage done previously.
how did we manage to come this far?

evolution my ass.

much compared to the damage being done in the Lakes.

If all sea-going ships had to off-load or on-load cargo in the St. Lawrence river at Montreal to rail, then contaminated ships could not penetrate the lakes. If required, the rail cards could be loaded onto railroad ferries based in Lake Ontario or their contents could be reloaded into bulk carrying lower lakers. Also, the lock and dam system between Montreal and Lake Ontario could be eliminated, which also would decrease the rate at which invaders would make it into the Lakes by swimming up the St. Lawrence. I doubt that would happen, though.

Perhaps the Great Lakes states should pool their money with Canada for research into how to control the population of the mussels and lamprey, since the U.S. Gov. doesn't appear interested, will not since Minnesota, Wisconsin, Michigan and New York are blue states, and northern Ohio and far northeastern Indiana are also blue.

The Great Lakes Charter is an agreement between GL states and provinces:

http://www.cglg.org/pub/charter/

Of course they have no real political power and despite the repugs lip service to state's rights and state control, the Bush administration would never allow the states to freelance regulation of the Great Lakes.