In the early 1930s, Britain found itself at war. The “invading armies” were “vicious (and) destructive,” threatened “man’s dominion of the earth,” and seemed capable of propagating at almost supernatural speeds. Politicians denounced the assailants in the House of Commons and the House of Lords. Scientists, called in to manage the unfolding debacle, prophesied utter devastation. “No limits other than the coasts can now be put with certainty to the infested area,” lamented one observer.
And what was the vile alien hellbent on conquering the British Isles? As the environmental historian Peter Coates reports in a delightful recent paper, it was that most ferocious, indefatigable, calamitous of beasts: the North American muskrat.
Muskrats — stout semiaquatic rodents, the size of teacup poodles, that excavate burrows, build lodges, and mark territories with their namesake scent — had been introduced to Britain in the late 1920s to provide cannon fodder for the fur industry. Although initially confined in a 60-acre pool behind mesh fencing, the critters (which aren’t actually rats) didn’t much tolerate captivity, and quickly gnawed their way to freedom. Soon wild ‘skrats were roaming Shropshire and Sussex, burrowing into canal walls and streambanks, and reproducing like, well, rodents.
Commence public freak-out: The invaders, zoologists and journalists predicted, would undermine railroads, breach dams, destroy flood defenses, transmit diseases, and just generally smear the weird gross stink of America around the bucolic British countryside. Back in their native environs, scientists averred, they’d been constrained by carnivores and cold weather. By contrast, Britain’s mild climate and predator-free landscapes would create a perfect Petri dish. There were thousands at large; no, hundreds of thousands; no a million. The rodents, Coates writes, had been “reborn through self-release, producing an unpredicted, unsanctioned beastly place widely characterized as “muskrat country.”
As a semiaquatic rodent aficionado myself, I read Coates’ enthralling study with great interest. Over the last several years, I’ve been closely monitoring another mammal’s spread throughout the United Kingdom: Castor fiber, the Eurasian beaver. Unlike muskrats, beavers are undeniably native to Britain — they may even have inspired the legend of the Loch Ness monster — but were extirpated centuries ago, before being reintroduced (both through governmental and, shall we say, sub rosa channels) in the last two decades. That crucial distinction notwithstanding, the fevered discourse that has attended the British rebeavering could have been drawn straight from the Great Muskrat Panic. Beavers, farmers have warned, will cost them untold thousands of pounds in flooded fields, collapsed flood defenses, and felled trees. In Scotland, they’ve been gunned down by anonymous assassins. When I interviewed employees of a British agricultural charity in 2017, they told me their constituents feared they’d “end up with a lot of pointy stubs in the ground, and not much else.’”
So what can we learn from Muskrat Mayhem that might be applicable to the Beaver Battle? First, as Coates reveals in his paper (which you really should read), the hand-wringing was likely much ado about nothing. Despite all the astronomical population estimates, muskrat numbers never surpassed 4,500 or so. What’s more, subsequent research actually suggested that Britain wasn’t prime ‘skrat habitat, and that the rodents would likely have been limited by natural fluctuations — or, in an ironic twist, by non-native mink introduced in the 1950s. Although journalists claimed that the muskrat’s presence in the U.K. was “probably eternal,” trappers extirpated them with relative ease in the 1930s.
Beavers, which engineer aquatic ecosystems in ways their little cousins could never dream of, have already left a far more indelible mark upon the British landscape. Still, it’s worth remembering that forecasts of rodent-induced disaster have been made, and debunked, before.
Which brings me to the second lesson: Trust the Bavarians! In 1932, Coates recounts, the British Ministry of Agriculture and Fisheries (MAF) hired Brendan Vallings, a cocksure Canadian trapper who boasted he’d shortly “clear the whole of England” of the pestilential mammals. Vallings, however, was accustomed to seeking out muskrat sign in the snow, and was all but helpless in the rain-soaked British countryside. The Canadian was out.
The desperate MAF sought aid next from mainland Europe. There, muskrats had run rampant since 1905, when a Czech nobleman returned from an Alaskan vacation with five live specimens and dumped them into his estate’s ponds. As the creatures bred and spread, the German state of Bavaria became the frontlines of the muskrat war, and the region’s biologists developed considerable skill at deterring the hordes. It was these experts — August Pustet, the state’s Director of Muskrat Control, and Adam Roith, a trapper with ten thousand notches on his belt — that Britain hired in January 1933.
The Bavarians arrived with guns blazing, armed with “rat divining” sticks (no word from Coates on how those worked, alas) and a new technique. “Instead of placing traps in the water, Roith caught muskrats alive in their burrows (runs),” Coates writes. Where the Canadian had failed, the Bavarians succeeded spectacularly. Within a year, the muskrats were in full retreat. By 1936, the last American interloper had become a mere pelt.
As it happens, latter-day Bavarians are also Europe’s leading beaver experts. Happily, Bavaria’s beaver population has been growing for decades, giving local biologists plenty of time to figure out how to harness their benefits and manage their impacts. The state’s beaver czar is Gerhard Schwab, a gentle polar bear of a man sometimes described as der alte Bibermeister. Not only has Schwab repopulated much of Europe (including the U.K.) with exported Bavarian beavers, he’s developed a network of volunteer conflict mediators ready to provide resources and advice to any landowner who finds his irrigation ditches clogged or his trees felled — and, if necessary, to live-trap and relocate the offending beaver. As beavers have recolonized Britain, advocates like the farmer Chris Jones (disclosure: a friend) have been visiting Bavaria in hopes of adapting the state’s beaver management model to their own country.
In the 1930s, it was Bavarians who taught Brits how to kill muskrats. Today, it’s Bavarians who are teaching them how to keep beavers alive.
As Coates notes, the “nonhuman empire” that muskrats founded in Britain hasn’t just fallen, it’s been virtually forgotten — the briefest footnote in faunal history. “Mental erasure complements physical obliteration,” Coates writes. “The muskrat does not even haunt former muskrat country on the signboard of a village pub.” With a bit of Bavarian assistance, the beaver’s reign should be vastly more consequential.
Top image: Muskrat, courtesy of Boston Public Library and Wikimedia Commons.