Is it Smart Policy to Kill One Fish to Save Another?

In many parts of the country, anglers and wildlife management agencies are wrestling with the issue of saving native fish, or wild fish, or certain sportfish species. And in some of those situations, the threat to the "desired" species is often another species. And the answer, in many cases, is to kill off one type of fish to protect the other.

It's a tricky situation, because in most of those scenarios, human manipulation of the ecosystem — often with good original intent — is the reason the problem exists in the first place.

In Colorado, for example, pike were introduced, and we now have some of the best pike fishing in North America. Problem (for some) is that those pike just love to eat trout. So in some places, there are now mandatory kill regulations — catch a pike and you are duty-bound to kill it. For certain invasive species, like snakeheads or Asian carp, that's not so much of a dilemma. Asian carp in the Great Lakes is a nightmare scenario that could devastate that fishery. Of course, that fishery depends on Pacific salmon and steelhead, which weren't in the Great Lakes at all until people put them there over 40 years ago.

The native trout in the Great Lakes is the Mackinaw, or lake trout. But years ago, when the lakes were severely impacted by industrial pollution and other factors, a number of lakers were transported and planted into deep, clean lakes out West. Now that's a problem in Yellowstone Lake, for example, where scientists believe the lake trout have decimated the native Yellowstone cutthroat trout population, and still threaten that species' very survival. Some would argue that the lakers are only one culprit among many, including whirling disease, predatory birds, and so forth. But now there's a massive undertaking to net and kill lake trout in order to protect the cutts.

People once thought it was a good idea to put brook trout in mountain lakes and streams out West. And in terms of creating an abundant, sustainable food source, it was. The brookies thrived, but at the expense of native cutthroats. Brown trout aren't native to anywhere in America, but we sure love them. And rainbows wouldn't live in places like Pennsylvania, New York, Texas and Hawaii if we didn't put them there. Many anglers are darn glad that we did.

So the question becomes, at what point do we accept "what is" now, and how hard should we try to make some order out of the genetic "pick-up sticks" that have been scattered all over the country's lakes and rivers over the past century and a half? Can we even untangle the situation at all, or is that just folly? We made our beds, so to speak, so now we have to lie in them... or do we?

I'm a romantic when it comes to fishing. And there is nothing more special to me than catching native fish in their native water. That trumps size. That trumps quantity. One native in a native place makes for the best fishing day I can imagine.

I'd gladly trade all the little brook trout in the stream by my house for a handful of greenback cutthroats. If that means poisoning the water and killing all the brookies to establish a new base in which to reintroduce natives, so be it. (You can't mess around if you're going to make real change; the invaders or introduced fish must be eliminated.) In the case of the lake trout, I sure wish there were more in the Great Lakes. And I know they're fun to catch. But I support efforts to get them out of places where scientists tell me (and I believe the scientists) that they threaten the native cutthroats. So kill 'em. Kill 'em all.

I wouldn't go so far as to suggest taking all non-native trout out of non-native waters. Does that make me a hypocrite? Maybe. I can live with that. But I do think we need to do our very best to leave native fish in native waters for future generations. And sometimes drastic steps call for drastic measures.

But that's just my two cents. What do you say?