Leave it to Beavers

Beavers (Castor canadensis), have been kicking around in North America for 2 million years. Ecologically they do all sorts of great things: their ponds ease flooding downstream, and support large numbers of bird species, fish, amphibians, and otters. They're what's called a keystone species, as in the keystone to an entire eco-system. But they're also the world's second largest rodent and a nightmare for property owners. Humans and beavers have a long history together because they like to live in the same places, but the way we've built our infrastructure has almost guaranteed our two species will be locked in eternal conflict.

We have created a trap for ourselves. A trap that ensures that we will come into conflict with nature’s most industrious rodent. A trap that also guarantees that we will come into conflict with each other as we try to sort out how to get out of this trap. That’s the conclusion I’ve reached, anyway, after spending the last few weeks researching beaver.

For seven years I said, you can’t kill them, you have to outwit them. That’s back when I thought you could actually outwit a beaver, but you can’t.
— Carol Leonard

Take Carol Leonard for example: a self-described “hippy-girl” who was the first registered midwife in the state of New Hampshire. (Incidentally, in what was perhaps the weirdest reporting coincidence I’ve ever come across, Carol was the same midwife who helped deliver me, 31 years ago.) When Carol retired to a beautiful 400-acre spread in mid-coast Maine, hoping to build her dream house, she and her husband ran head-first into conflict with beavers. A growing dam led to an expanding pond that was getting ominously close to where Carol wanted to put her septic system.

A pick-up truck swallowed whole by a beaver dam. | Photo Courtesy of Mike Callahan, beaversolutions.com

A pick-up truck swallowed whole by a beaver dam. | Photo Courtesy of Mike Callahan, beaversolutions.com

“For seven years I said, you can’t kill them, you have to outwit them,” Carol told me. “That’s back when I thought you could actually outwit a beaver, but you can’t.” Eventually Carol apprenticed to become a trapper. Her decision was that if she couldn’t outwit them, she would eat them. “I always thought I was on the other side, when I was doing my midwifery, so it always surprised me when I got into trapping.”

Beavers and people like to live in the same places, and if you pick a fight with a beaver, here’s what you’ve got to consider: we’ve got other stuff to do—jobs, meals to cook, soccer games. Beavers on the other hand, they do one thing: build dams.

So if, as in Carol’s case, a beaver were eyeing the same spot that you wanted to live, what would you do?

First We Eliminated the Beaver

If you’ve never seen a proper, massive beaver dam before, you need to get yourself over to Google image search right now and look at some. The biggest one in the world is about a half a mile long and 13 feet tall, and was identified from outer space.

Beaver teeth grow constantly, and they actually have to keep chewing wood to keep them in check. And yes, they do actually just eat wood: they eat the cambium, the soft spongy layer of new growth that’s just under the bark.

On the ecological side, beavers do all sorts of great things. Beaver ponds help to ease flooding downstream. They slow water down as it rushes towards the ocean, meaning they help to recharge drinking water aquifers. Their ponds support large numbers of bird species, fish,  amphibians, otters. They’re what’s called a keystone species, as in the keystone to an entire ecosystem.

Beaver have been kicking around in North America for 2 million years. What’s new, on the millennial time scale, is Europeans.

When the Europeans arrived in the US, first came the fur trappers and fur traders, driven by intense demand for top hats, made from felt which is made from beaver fur. (Because nothing says class like putting the world’s second largest rodent on your noggin.) They traded extensively with Native Americans, and paid them for every pelt they brought. After the fur traders, came the farmers.

On the ecological side, beavers do all sorts of great things.
chewed log_P1180716.JPG

“Beaver were going to be both a source of cash for these settlers and, of course, a problem for these settlers, because beaver are competing for the same environment,” explains Ann Carlos, economic historian from the University of Colorado Boulder.

Beaver ponds, once the dams are destroyed and the water drains, turn into something called beaver meadows, which are fantastic places to grow crops. So farmers come in, trap any beaver that are left, destroy the dams, drain the ponds and make their fields. One study found that sixteen states lost more than 50 percent of their wetlands as the settlers rolled in. Another six states, mostly in the Midwest, lost more than 85 percent.

“By about 1830, many of these populations were being seriously over harvested, and run down,” notes Carlos. This was especially true in the United States, where all throughout the Northeastern part of the US, beaver were virtually wiped out.

And Then We Set The Trap

Meanwhile, year after year, we’re building. Those farms built on old beaver ponds are connected together by roads. More of the fields are subdivided and turned into housing developments. Bit by bit, we occupied the space the beavers once held.

Pat tate with a local beaver's handiwork | Photo: Sam Evans-Brown

Pat tate with a local beaver's handiwork | Photo: Sam Evans-Brown

Then in the early 1900s, we brought the beaver back. Why? Because for one, biologists had begun to recognize how good they are for ecosystems. But also people like having beaver around as a game species. In other words, an animal that is around so they can be trapped. So wildlife agencies reintroduced them and helped them build back up until they numbered in the thousands.

“Our roads were based on native American trails—a high number of them—and a high number of those native american trails were based on game trails. And I can say as a hunter who has walked all over the state of New Hampshire, their preferred wetland crossing every time has been a beaver dam,” explained Pat Tate, the furbearer biologist for Fish and Game here in New Hampshire.

In other words, many of our roads have been built the same spot that beavers like to build their dams. And in the cases of bridges and culverts, we punch a tiny hole through those roads for the water to pass, which is like a giant blinking arrow to any beaver that encounters it, indicating “build your dam here!”

So What Do We Do? Kill them?

The paradigm under which we currently operate is called the American system of wildlife management, under which wildlife is a commonly owned resource, and through regulation we decide how many animals we will kill. Are deer eating the shoots off of too many saplings out in the forest? Increase the number of deer hunting permits issued. Are farmers complaining about losing livestock to coyotes? Relax limitations on hunting them. Are there so many beaver that they are expanding wetlands until they flood wells and roads? Call in trappers to reduce beaver populations in that location.

This ensures that the population stays below what is called the “biological carrying capacity” which is a fancy science-y way of saying “how many beaver the land can sustain.” Pat Tate is a big believer in keeping animal density low, because he believes it makes the animal’s lives better.

I once removed a beaver that had a beaver-tooth in its back, and it didn’t grow its own tooth in its back, that was a tooth from another beaver that somehow broke off in the animal’s back.
— Pat Tate
Jeff Traynor shows us one of his beaver traps. The stick is the food. | Photo: Logan Shannon

Jeff Traynor shows us one of his beaver traps. The stick is the food. | Photo: Logan Shannon

Beaver are very territorial animals. When a young beaver reaches two-years-old, they strike out on their own to find their own water body to live in. Often they have to battle other adult beavers to find their place. “I once removed a beaver that had a beaver-tooth in its back, and it didn’t grow its own tooth in its back, that was a tooth from another beaver that somehow broke off in the animal’s back,” Pat said, “As I’ve reduced numbers in the wetlands, and went back subsequent years to trap, the amount of scarring and bite-marks on the beaver decreases. So the individual animal’s health increases.”

Most trappers aren’t doing it for a living, or to feed their families they do it because they want to. They want to connect with a tradition they identify with, or maybe they just like getting outside, and doing the close observation of nature that trapping requires.

And trappers I’ve spoken to hear a lot of hypocrisy whenever they hear people call trapping immoral. For instance, a trapper from Southern New Hampshire, Jeff Traynor, points out there isn’t the same outrage at housing developments or highways or parking lots: forces that have just as much to do with keeping beaver populations low.

“We are the most invasive species on the planet, there’s no doubt about it,” he told me, “As we encroach more we’re pushing them. So where is that overflow going? There’s only so many places that they can go. It comes to a point where you can say, well let’s just let nature take its course, or you can say, as human beings can we manage this creature with moral wisdom?”

Jeff Traynor prepares a trap. | Photo: Logan Shannon

Jeff Traynor prepares a trap. | Photo: Logan Shannon

One of jeff traynor's traps under a thin layer of ice and snow | Photo: Logan Shannon

One of jeff traynor's traps under a thin layer of ice and snow | Photo: Logan Shannon

After chopping away at the ice, jeff Prepares to check the trap. | Photo: Logan Shannon

After chopping away at the ice, jeff Prepares to check the trap. | Photo: Logan Shannon

Or Just Keep Them Off Our Lawns?

But this “moral wisdom” argument, just doesn’t do it for many beaver believers. Skip Lisle, founder of Beaver Deceivers International, has heard this argument for years in his line of work, and doesn’t buy it. “You know, you always hear, we have to kill the beavers so they don’t get hungry. And if you were an individual beaver, you can imagine which choice they would choose if they had one to make, right? Would you rather be hungry or dead?”

The proponents of restricting beaver trapping often point out that while some management decisions are based on ecosystems science—with government biologists going out and to try to estimate how many animals the land can sustain— other times, the decision is based on our willingness to tolerate animals. This is, almost euphemistically, what we call the “cultural carrying capacity.” And for beavers, it’s often that cultural limit, and not the actual limits of the habitat, that they bump up against.

Beavers are a two-million-year-old species, right? By some miracle, they survived just fine. They suffered, they died, they thrived, but they did it on their own, like most species do. You know we don’t manage chickadees so that some chickadees aren’t hungry sometimes.
— Skip Lisle

Skip and his disciples argue they can increase society's tolerance for beaver by keeping the two species from coming into conflict. Beavers’ damming instinct is triggered by running water, and by using a clever arrangements of grates, culverts, and drainage pipes, Skip keeps beaver far enough away from the running water that they don’t get the urge to start building a dam.

By putting in this type of “fixed protection” whenever a conflict arises, Skip argues we can have the best of both worlds: a growing beaver population and an infrastructure that isn’t submerged under beaver ponds. For him, the argument that trapping leads to a healthier population is beside the point.

This is a pond leveler or flow device, prior to being installed. This device tricks the beaver into believing that his or her dam is working. | photo courtesy of Mike Callahan.

This is a pond leveler or flow device, prior to being installed. This device tricks the beaver into believing that his or her dam is working. | photo courtesy of Mike Callahan.

“Beavers are a two-million-year-old species, right? By some miracle, they survived just fine. They suffered, they died, they thrived, but they did it on their own, like most species do. You know we don’t manage chickadees so that some chickadees aren’t hungry sometimes.”

These pipes and fences, limit where and how much habitat beavers can make. When the young beaver in these beaver colonies move out of their parents lodge, they won’t be able to just make this pond bigger and move to the other side. Instead of coming into conflict with humans who live close to the pond of their birth, they set off over land, and come into conflict with things that normally keep beaver populations in check: predators or other beaver.

Or maybe they’ll just wind in somebody else’s backyard; someone less dedicated to a non-lethal intervention.

What Would Happen If Trapping Went Away?

In 1996, animal welfare groups put forth a ballot referendum in Massachusetts proposing to eliminate the use of ,what they considered to be, inhumane traps. The referendum passed, making Massachusetts one of a handful of states to restrict the use of the standard trap that is used to kill beaver. After the referendum passed, the beaver population tripled in just a few years. (Though local wildlife advocacy groups argue this would have happened even if trapping was left in place.)

“As a result, the conflicts with people and the complaints essentially skyrocketed,” said Dave Wattles, the furbearer biologist for MassWildlife.

Mike Callahan of BeaverSolutions.com installed a flow control device on our beaver pond, to maintain the pond at its current level.

While the beaver advocates likely see the population boom as a victory, the rise in complaints had unintended consequences. In 2001 the state legislature passed a bill allowing kill trapping to be done through an emergency permitting process. Now though, those permits are given out by towns, instead of the state. This means that the state is no longer collecting data about how much trapping happens in Massachusetts, and that beaver can be trapped in the spring when it's possible to kill mothers, thus leaving young kits abandoned.

Dave Wattles also notes that beavers killed under a nuisance permit aren’t necessarily used for meat or fur. “The beaver that are now taken during these emergency permits, quite often they’re just trapped and thrown into a landfill and not used at all.”

What Would You Do?

Carol Leonard, who started off our story, spent seven-years trying to figure out how to fool the beavers on her property. “In my naivete I said oh well we’ll try these beaver deceivers and these beaver bafflers and all these do-hickers,” she recalled. But eventually she gave up and apprenticed with a trapper, and started to trap out the animals that threatened her property.

I think the traditions of hunting and trapping in New England are good, healthy traditions. And I can’t talk against hunters… I can’t. I’m a meat-eater.
— Carol Leonard

“We are meat eaters, you know, we are hunter gatherers, it’s part of who we are. And so to be able to turn a blind eye to that is just a blind eye,” she said. She applauds animal rights activists, but says she thinks their efforts are better spent protesting concentrated animal feeding operations, or other places where animals live short and miserable lives before heading to our plates.

“I think the traditions of hunting and trapping in New England are good, healthy traditions. And I can’t talk against hunters… I can’t. I’m a meat-eater."

Carol says she has trapped somewhere in the neighborhood of 30 beavers from her property, and while many still remain just downstream, the pond that was threatening her septic setback is no longer growing. In 2015, she and her husband were able to start construction and their home, now completed, is gorgeous, judging from a recent photo spread done by Down East Magazine.

Beavers and people, we like to live in the same places. And if you ever find that a family of them are eying the same spot as you... well, good luck.


Outside/In was produced this week by:

Sam Evans-Brown, with help from, Maureen McMurray, Molly Donahue, and Jimmy Gutierrez. Logan Shannon was our digital producer.

Thanks this week to Ben Goldfarb, Dave Wattles, and Peter Busher, all beaver pros who helped me sort this week’s story out.

If you’ve got a question for our Ask Sam hotline, give us a call! We’re always looking for rabbit holes to dive down into. Leave us a voicemail at: 1-844-GO-OTTER (844-466-8837). Don’t forget to leave a number so we can call you back.

Music this week from Ari De Niro, The Marian Circle Drum Brigade, Blue Dot Sessions, Revolution Void, Jason Leonard and Podington Bear. Check out the Free Music Archive for more tracks from these artists.

Our theme music is by Breakmaster Cylinder

Outside/In is a production of New Hampshire Public Radio.

Eat the Invaders - Lionfish

This is Eat The Invaders - our occasional segment where we take a bite out of invasive species populations. On the menu today, one of the scariest, most voracious and intractable invaders out there: the lionfish.

After much discussion, the team over here at Outside/In has decided that lionfish look like a tropical fish, crossed with a peacock, crossed with a zebra, crossed with a set of Scottish bagpipes. They are flashy fish. It’s really no surprise that people with fancy aquariums like to show off by putting lionfish in them.

And really, once there were aquariums full of lionfish all over the country, it’s also no surprise that the fish got out. The mythical tale is that the current lionfish invasion began in 1992 when Hurricane Andrew rolled through Florida and smashed up an aquarium in Biscayne Bay. This story persists, even though the fish were actually first seen off the coast of Miami years before, and the biologist who suggested that theory has since discounted it.

It’s much more likely that this lionfish invasion started when disgruntled aquarium owners purchased a lionfish, discovered that the fish had a voracious appetite for their other favorite fish in the tank, and opted to dump their new purchase into the ocean.

Once there were enough free fish to find each other and breed, the stage was set for one of the most epic invasions ever observed.

The fish are a gape limited predator, meaning they will try to eat anything they can swallow. They are also suction feeding fish, meaning when they open their mouths, water rushes inside, “so the lionfish basically turns into the death star and it has this tractor beam. That’s how bad it is,” explains Rachel Bowman, a lionfish spearfisher from the Florida Keys. Lionfish feed on small reef fish that are a huge part of the ocean food chain, and one study in the Bahamas found that in just two years their arrival led to a 65% decline in the quantity of local fish.

Like many invasives, Lionfish are also prolific breeders. One female can lay 30 million eggs in a single year. Put those two things together—voracious appetite, and the ability to multiply exponentially—and you’ve got a spiny, bag-pipey, marine disaster.

Oh, and did I mention they are venomous? “I don’t have kids, but a friend of mine who has a son has told me that it’s right up there, it’s right up there with childbirth,” says Rachel, “It feels like your bones are expanding from the inside out.”

Luckily, they have one weakness we humans love to exploit: every fish yields two tasty fillets.

Lionfish meat has been compared to hogfish which is a cross between lobster and shrimp, grouper, snapper, and any number of things, but I would say that as a New Englander with a not terribly refined palate for such things, the fish tasted like any number of flaky white fish that you can get at the grocery store.

And speaking of the seafood counter, Whole Foods became the first grocery chain to offer the fish in its Florida stores this spring.

Now, you can find a smattering of articles out there with splashy titles like: “Why eating invasive species is a bad idea,” or “Eating Lionfish: effective conservation or a cure worse than the disease.”

As far as I can tell, the primary knock against the eating of lionfish is that it’s simply not an effective way to combat the invasion. And it may be true that no matter how many fish we spear, more will simply take their fallen comrade's place. I mean, 30 million fish eggs per female lionfish? Seriously, how do you compete with that?

We cooked the lionfish two ways: baked in butter, lemon, shallots, and white wine; and Spicy Grilled style. The first preparation was adapted from this basic recipe for cooking white fish. The second was adapted from a Rick Bayless recipe, with instructions below. 

Rachel says on a good day, she’ll spear 120 pounds in a day. And when she’s been diving on the same reef for a few days, she says they do start to get harder to find, but after just a month or two of not being patrolled, reefs fill back up with the fish. And even then, spearfishers are only helping at the depths they can reach by diving in scuba gear. “I’ve got a brother in law that’s a commercial lobster trapper, and he pulls up traps from four, five, six hundred feet and they’re full of lionfish,” she says.

But, to the critics, Rachel points out every person who picks lionfish off a menu, is a diner who isn’t eating something else—grouper, or snapper, tasty fish which have a history of being over-eaten. And besides, what’s the alternative? Do nothing?

“You know what, it’s a hell of a lot better than sitting on the couch and saying you can’t put a dent in that population. I’m doing something,” she says, “And those people that sit there and say, well you’re not going to be able to make a difference. No, no one has ever made a difference by sitting there and saying that, have they?”



Outside/In was produced this week by:

Sam Evans-Brown & Logan Shannon with help from Maureen McMurray, Taylor Quimby, Molly Donahue, and Jimmy Gutierrez.

Special thanks this week to the REEF Environmental Education Foundation for helping us to find Rachel, and to Norman’s Lionfish for over-nighting some freshly caught—and conveniently de-spined—lionfish to us.

If you’ve got a question for our Ask Sam hotline, give us a call! We’re always looking for rabbit holes to dive down into. Leave us a voicemail at: 1-603-223-2448. Don’t forget to leave a number so we can call you back.

Our theme music is by Breakmaster Cylinder

This week’s episode featured tracks from Blue Dot Sessions and David Szesztay. Check out the Free Music Archive for more tracks from these artists. 

Never Bring a Sledgehammer to a Scalpel Fight

When a Harvard professor accidentally let Gypsy Moths loose in the 1860s, he didn’t realize he was releasing a scourge that would plague New England forests for more than a century. Nothing could stop the moths except a controversial method of wildlife management called biocontrol. It’s the scientific version of “fighting fire with fire”: eradicate an invasive species by introducing another invasive species. Since then, there have been lots of biocontrol success stories, but also a few disastrous failures. In this episode, we ask whether biocontrol is the best--maybe the only way--to combat invasives, or if it’s just an example of scientific hubris.

Show of hands. Say you had a swarm of wood-boring beetles and you wanted to get rid of them. These beetles were never supposed to be here—they were brought in from Asia, unintentionally. Would a good way to rid yourself of them be to introduce a parasitic wasp, also from Asia, that would probably beat the beetles down?

Anyone?

We have been hard-wired to recognize this as folly. Exhibit A: The Simpsons.

In this episode, Bart accidentally introduces a pair of invasive Bolivian tree lizards into the town of Springfield. The local bird club is horrified at first, but then delighted, when it turns out the lizards’ preferred food is pigeon meat.

 
 

This idea—using nature to fight nature—is called classical biological control or biocontrol. And examples abound of when it’s gone horribly wrong.

For instance, this spring, New England experienced the worst outbreak of invasive gypsy moth caterpillars in more than 30 years. The last time the caterpillars were this bad the forest they denuded (they eat leaves) was an area bigger than the states of Connecticut, Rhode Island, and Massachusetts combined. This year, you could see their impact from space.

We’ve been trying to control the gypsy moths for over 100 years. In 1906, the US Department of Agriculture released a parasitic fly—Compsilura concinnata—in hopes that it would kill the gypsy moth caterpillars. But this fly was something of a sledgehammer. Yeah, it killed some gypsy moths, but it also killed lots of other kinds of moths, too. Two hundred types of moths, to be precise. Among the fly’s unsuspecting victims were the so-called giant silkworm moths—luna moths, cecropia moths, royal walnut moths—which are almost totally benign and often staggeringly beautiful. One study found that the fly killed as many as 80 percent of cecropia moths, which, at about the size of your hand, is North America’s biggest moth. For all that, it didn’t have a lasting impact on the gypsy moths–they tempered the attack well. 

a lovely little luna.

a lovely little luna.

This story is not unique—introduced mongooses have decimated Hawaii’s native birds, and cane toads have caused a decline in Australia’s adorable northern quoll populations—and they have served as a cautionary tale (or as a cult classic documentary for high-school stoners) for decades now. They help flesh out the narrative of humanity as giant-sized children, stomping about in nature, wielding a power whose consequences we are far too simple to understand.

And yet, we still use biocontrol. The first bullet on the USDA’s biocontrol website asserts “it is easy and safe to use.”

Will we never learn? Actually, biocontrol advocates argue, we already have. What’s more, even with all the horror stories, biocontrol has a better record than we think.

Consider again the case of the gypsy moth. The parasitic fly was no good. But twice in the 20th century—first in 1910 and 1911, and then again in 1985 and 1986—scientists tried to introduce a fungus, Entomophaga maimaiga, that they believed would kill gypsy moths. Neither introduction survived, but then mysteriously, in 1989, the fungus took off in Connecticut. It’s now credited with reducing the population of leaf-munching caterpillars by 85 percent, as long as it's wet enough for the fungus to thrive.

But here’s the kicker, the fungus works like a scalpel; there’s almost no collateral damage. Of 1,500 dead insects collected in an area where the fungus was present—representing 53 species—only two individual (non-gypsy) moths had been killed by the fungus, according to a field study.

What’s more, despite the skepticism evident in the writers’ room at The Simpsons, the history of biocontrol is largely a history of scalpels, not sledgehammers.

Two recent studies have asked the question: how safe is biocontrol? One assesses insects introduced to kill other insects, and the second looked at insects introduced to eat weeds. Both found that when biocontrol is conducted by scientists, it has a pretty darn good safety record, with more than 99 percent of introductions having no significant impact on any “non-target” species. 

 
 

That doesn’t mean they all work. Somewhere between 50 and 70 percent of introduced biocontrol agents fail to establish themselves at all. Only 10 percent fully control the pest they target.

Still, there are some smashing success stories out there. Purple loosestrife, a plant that clogs up streams and rivers and has been declared a “noxious” invasive weed by 23 states, has been tamed by four species of European loosestrife beetles, which have been seen to eat up to 90 percent of the weed in some spots. In the 70s, several countries in Africa started to see massive crop failures of cassava, a plant that feeds hundreds of millions of people all over the world. Scientists found a tiny wasp which very specifically targeted the bugs that were eating the cassava, and today crop damage from the so-called cassava mealybug has declined by 90 percent.

Further, the entire practice is being much more carefully regulated these days. Biocontrol introductions in the U.S. have been slowing down since the 80s, and in 2000 the USDA began requiring biocontrol projects to go through a permitting process that includes testing to ensure that impacts to native species will be minimal. 

 
 

The idea that biocontrol is a poorly understood tool being wielded by irresponsible scientists is “kind of an old fashioned view actually,” says Cornell entomologist Ann Hajek, “Those dangerous introductions aren’t being done anymore.”

So why do we only hear stories of biocontrol gone horribly wrong? Because it’s a better story, one that fit the narrative of the early environmental movement: we’re trashing the planet.

In the early days, biocontrol was believed to be an environmentally friendly alternative to pesticides. So in 1983 when an entomologist named Francis Howarth assembled in one place all of the horror stories of biocontrol gone wrong it was “a man bites dog story,” says Russell Messing from the Kauai Agricultural Research station in Hawaii. He says bashing on biocontrol became a “fad” in ecology. “A lot of people jumped on board, and there were a lot of papers published, and even some reputations made, I think,” he says. 

Howarth is retired, but the torch of biocontrol skepticism today is carried by Dan Simberloff, at the University of Tennessee.  Simberloff says that even in its more strictly regulated form, modern biocontrol still risks driving rare native species into extinction. 

As his example, he points to efforts to control the emerald ash borer, a beetle currently destroying ash trees all over the eastern United States.  There are more than 100 species of native “jewel beetles” and he says “some of them are so rare that they’re only collected by entomologists once every decade, if that.” His argument is that USDA scientists could not have possibly checked all of those myriad beetles to be sure they wouldn’t be preyed upon by the parasitic wasps currently being released to combat the emerald ash borer. We could annihilate a species of native beetle, and not even realize it for years.

But what then is one to do about the invasive emerald ash borer, which has killed more than 90 percent of the ash trees it infests (and as go those ash trees, so too go the 44 species of native insects that depend on ash trees to survive)?

“I don’t really know what to do,” Simberloff says.

Indeed.

“In the absence of biocontrol there is no solution,” says biocontrol researcher Joe Elkington, at the University of Massachusetts Amherst, “I mean, there’s no solution.”


Outside/In was produced this week by: 

Sam Evans-Brown, Maureen McMurray, Taylor Quimby, Molly Donahue, Jimmy Gutierrez, & Logan Shannon

Theme music by Breakmaster Cylinder 

Photos of Sam are by Greta Rybus unless otherwise noted.

The Kiwi Apocalypse

…or, how Sam Learned to Stop Worrying and Love the Cold Hardy Kiwi.

Iago Hale has a vision: it’s one where the economy of the North Country is revitalized by local farmers selling delicious cold hardy kiwi berries to the masses.

Meanwhile, Tom Lautzenheiser has been battling a hardy kiwi infestation in Massachusetts for years, and is afraid that this fight will soon be coming to the rest of New England.

Should we worry about the cold hardy kiwi and what does the quest to bring it to market tell us about what an invasive species is?

Listen to the episode:

Check out photos of Sam's new favorite fruit: