Aliens Unwelcome

I hate to break it to you, fellow intrepid anglers, but our lakes and rivers in North America are, once again, in real trouble.... and that’s trouble with a capital “T”. We have yet another alien entity in our midst. Relax. It’s not an Extra Terrestrial, but one from Eurasia, right here on earth, one that is threatening our freshwater fisheries. Remember acid rain (which was of our own making) and what it did to our waterways and fish populations? Of course you do. We managed to reduce and control it, fortunately. You may also remember destructive alien invaders like round gobies, zebra mussels, sea lamprey, Asian carp and others, all of which are still affecting our North American fisheries. Well, now there is something else threatening our waters, something magnitudes worse than the others, in that it is more damaging and widespread and much harder to control. It is an invasive, aquatic, perennial plant named Eurasian Water Milfoil.


Attack of the Killer Plant

If you’re an avid angler, as I am, you have doubtless encountered this ubiquitous water plant. First discovered in Lake Erie in 1961, this Godzilla of invaders, the most insidious and most widespread scourge of our waters, has to be the Eurasian Water Milfoil (EWM), a plant, which often breeds with our native milfoils, making it extra aggressive. If you fish or boat, then you have most likely encountered this interloper. In its way, it is an attractive plant, with elegant, green, feathery leaves or fronds, five or more branching from and encircling each node of the stem. Right about now, you’re all going, “Oh, yeah! That plant! !#*”#!” Eurasian milfoil sure gets around and now exists and thrives on every single continent, save Antarctica. It has been found in 48 of the contiguous states in America and also in Ontario, British Columbia, and Quebec in far, that is. It is incredibly prolific and even the tiniest, broken-off piece can form a new plant, making it extremely hard to control. I don’t have to tell that to all you boaters, cottagers or swimmers. Yes, that’s the “weed” that, maddeningly, becomes twisted around your boat propeller, or tickles your stomach as you go for a leisurely swim, or fouls your hooks when trying to tempt a big bucket mouthed bass to go for your offering.
Those things are merely annoying but the Eurasian milfoil also does very serious damage to our waters and all the denizens therein. The U.S. Fish and Wildlife Service recently declared that “America’s fisheries are facing a conservation crisis. Nearly 40% of North American fishes, 700 species in total, are imperilled. More than two-thirds of these are listed as threatened or endangered under the Endangered Species Act. Habitat alteration is the principle factor in this conservation crisis...” Eurasian milfoil is one of the causes of fish habitat degradation. None of us would like to see even one of our favourite fishing haunts affected to the point that fish begin disappearing. It is incumbent on us to take action. The consequences of not acting will be dire, indeed.


Crazy Uncle Ned

Why dire? Allow me to explain. When Eurasian milfoil takes root, it is extremely difficult to remove or even control, much like when uninvited, crazy Uncle Ned comes to visit and you can’t pry him out of your house with a crowbar. Wait, though. It gets worse. Milfoil often grows 300 plants strong within one square meter of lake bottom. Two is company but 300 is a crowd, I’m sure you’ll agree. This means the density of a milfoil bed is such that, to find cover, even the tiniest fish cannot penetrate the wall of plants, let alone our marauding friends like the pike and musky, which depend upon good cover from which to launch their attacks. To compound things, huge mats of Eurasian milfoil that now choke many of our lakes, decompose every winter, drastically reducing oxygen levels and killing many fish, and, in shallow areas, make for stagnant water which breeds hordes of mosquitoes. As well, often the sandy or gravelly bottoms so necessary for spawning fish like the basses and trouts are disappearing, choked with milfoil.

Not only that, but there is evidence that fish diversity and size of populations are sorely affected, which, in turn, affect the quality of freshwater fishing. It’s enough to send an angler into conniptions. More and more, spawning beds are being reduced and that of course, means fewer wild fish will be available. More and more, we are dependent upon our stocking programs to maintain quality fishing rather than the way it used to be done, (i.e.) naturally, via Mother Nature. Eurasian Water Milfoil is a really bad actor. We need to control it, you, me, citizens and governments alike, because this has the potential to affect all of us.


Show Me the Money

Consider this. In Ontario alone, the average angler spends about $800 a year, money spent on: boating supplies, gasoline, accommodation, food, bait and fishing tackle. Multiply that by the millions of anglers in Ontario and across North America and, if the quality of fishing is degraded, we are talking about potential losses of billions of dollars to our economies. That’s right. Billions. According to The American Sport Fishing Association, fishing generated more revenue ($48 billion) than Lockheed Martin ($47 billion), Intel ($44 billion), Chrysler ($42 billion) or Google ($38 billion). That is a lot of lettuce by any reckoning. Sport fishing in the U.S. alone generates 828,000 jobs. That’s a lot of paycheques, my friends. I hope you see now that controlling Eurasian milfoil is essential, not only for our economies, but also for the unquantifiable pleasure we derive from fishing and water sports.


You’re Under Arrest

Short of poisoning and sterilizing entire lakes, it is virtually impossible to eradicate Eurasian milfoil, so we need to concentrate on reducing as much of it as possible. There are several ways we are attempting to do this. One method is by Mechanical Harvesting, which is fine, except that tiny broken bits just reseed the lake bottom after the harvester has passed, making it necessary to do it all over again each summer.....same as mowing your lawn; you have to do it repeatedly.

Another method is Chemical Extermination. Trouble is, most chemicals used are broad-spectrum and also kill native plants. As well, many jurisdictions will not permit its use, for obvious reasons. A more promising method, at least we thought so initially, is Biological Control. Milfoil Weevils, small aquatic insects, have been imported and introduced into many lakes, with some minor success. However, a number of factors conspire to keep the needed density of these critters down to a point where their impact on milfoil has been minimal on a large scale.

Here Comes the Cavalry

Take heart, my friends, because an exciting, new method of control is being developed currently, a method approved of by the non-profit group, Agence de bassin versant des 7 (ABV des7), environmental consultants out of Gatineau, Quebec. The method consists of huge blankets of a burlap type of mesh material, weighted so that they sit on the bottom, suffocating all the milfoil beneath. Happily, native plants can grow through the mesh while milfoil cannot. To top it off, the blankets are biodegradable over time, totally environmentally friendly. How great is that? A similar method is being used in the US but the blankets consist of a plastic-like material, which is not biodegradable. Folks, stay tuned because this could be the very method of control that we are looking for.


Without a doubt, it is virtually impossible to completely rid our watercourses of the various alien invaders making their homes there. However, as I hope you have seen, control is not only possible but essential. What can I, as an individual, do to help out? Glad you asked. Number one, make sure your boat, inside and out is clear of even small bits of milfoil, possibly clinging to your anchor, brought into the boat while fishing, or left in your live wells. Bigger boats need to flush their bilges and ballasts, too. Two, hose down your boat and trailer prior to boating in a different lake. Don’t make a bad situation worse by unwittingly transporting milfoil to unsullied waters. That is precisely how we got into this mess in the first place. Three, keep an eye out for the availability of the newly developed blanket method mentioned above and tell your friends about it. It’s coming soon.

With the help of like-minded anglers, boaters and cottagers, we can, to paraphrase a certain orangehaired man, help make our waters great again. Tight lines, everyone!

If you have time, when not fishing, here are some references for further reading:

Lovell, S., Stone, S., & Fernandez, L. (2006). The Economic Impacts of Aquatic Invasive Species: A Review of the Literature. Agricultural and Resource Economics Review,35 (1), 195-208. doi:10.1017/S1068280500010157.