Some years back I’d compressed an early-summer float on the North Fork of the Shoshone River, near Cody, Wyoming, into a tight window that required an all-day drive to Kalispell beginning the following morning.
I recall the take-out just above Buffalo Bill Reservoir was especially muddy. That’s how it is on the eastern edge of Yellowstone, in the fallout zone of the caldera. That country is covered with powdery soil, a remnant of the ash clouds that volcano pumps into the sky.
As we loaded I had to climb in and out of the raft a couple of times, tracking mud in the boat each time. At that moment I noticed the mess I’d made, but we loaded in a hurry. Dinner in Cody was our planned destination.
Needless to say, I forgot about the muddy floor of my raft. Forgot about it until I pulled up to the boat inspection station in Ravalli the next day.
I was mortified.
The guys at the inspection station were nice enough, however. They seemed eager to break out their power washer and put it to use. We had a nice visit and my boat ended up as clean as it had been all season.
No harm, right? In this case, there hadn’t been. While we chatted, the guys at the check station told me the Shoshone was on the list of waters infected by New Zealand mudsnails. And while mudsnails had already made their way to Montana, they weren’t yet in the Flathead.
If not for that power washer I might have been Patient Zero.
I wasn’t headed straight for the river and I would have had plenty of time, once I reached Kalispell, to wash out my raft. But it’s a cautionary tale that someone with a background and awareness of invasives could make a boneheaded mistake like that.
I know why it happened — I was in a hurry from the moment I took out on the Shoshone until I pulled into the check station in Ravalli. I forgot to hose out the boat the evening before and that morning with my stuff already loaded, I didn’t bother to give things a proper close inspection before I started driving. But still …
I’ve been writing about threats to Montana’s treasured wild places due to imported diseases and invasive species for about 30 years. I reported on whirling disease when it was first detected in the Madison River in the 1990s when the river’s rainbow trout population had crashed by 90%. We treated whirling disease as if the apocalypse was upon Montana trout streams. It looked bad. Really bad.
It turned out to be not quite as devastating as predicted. While there’s no cure, whirling disease doesn’t infect brown trout. And the surviving Madison River rainbows — while not immune — have demonstrated a resistance to the disease. You don’t hear much about a fishless Madison these days.
This is not to say we shouldn’t concern ourselves with boneheaded moves such as my trailering a muddy raft across half of Montana. Madison River rainbow trout have mostly recovered, but may never get to where the population was before whirling disease spread through the watershed.
Each new invasive species or disease is a roll of the dice. Maybe the ecosystem will prove resilient enough to recover and muddle on, but maybe not.
Mudsnails are on my mind because they just turned up in Silverbow Creek near Warm Springs Ponds. This is the first time the snails have been detected in the upper Clark Fork watershed. Mudsnails don’t carry disease, but these invasives breed quickly, asexually, and once established compete with aquatic insects that trout feed on.
Trout will eat mudsnails, but studies indicate more than 50% pass through the digestive tract still alive. Mudsnails may fill a trout’s belly, but like a deep-fried Twinkie at the county fair, they don’t provide any nutrition.