The Bullwinkle Experiment

By Mark Wheeler|Tuesday, July 01, 1997
RELATED TAGS: ECOSYSTEMS
To get a feel for what biologist Joel Berger does, I’ve donned his moose suit and am sliding down a snow-covered embankment to stand, panting, thigh-deep in snow. Minutes later I’ve managed to flounder my way within 30 yards of a real-life Bullwinkle J. Moose, which, despite my total lack of discretion, still has not bolted. I’m sure that’s because I’m not close enough to be a threat, and since survival in this harsh Wyoming winter depends on burning as few calories as possible, it’s not going to expend precious energy until it absolutely has to. That, or it’s thinking, Oh brother, not the doofus in the moose suit again.

Still, big Alces alces is giving me the eye, warily. Warily, I’m giving it the eye back. Moose can be cranky--not a good disposition, to my way of thinking, when combined with size. This moose is your average Al, roughly 7 feet tall and 1,000 pounds, with a dangling piece of fur below its muzzle, ears like a mule’s, and scar tissue above its eyes from where its antlers shed back in December. Appreciating a moose for its looks must be an acquired taste.

In truth, though, I’m having trouble seeing the moose at all because I don’t have my head on straight. As a result, the little mesh eyeholes in the neck are off kilter. As I try to yank everything back into position, the head gets caught in a branch that pulls the woolly material completely over my eyes. Now I can’t see at all.

Why am I here? you ask. Or you would, if you knew that here is Jackson Hole, in February. I’d come to visit Berger in his office, the Greater Yellowstone Ecosystem, 18 million acres of the great West stretching roughly from Yellowstone National Park some 55 miles south, through a chunk of Grand Teton National Park, and on to Jackson Hole. Due west is the east face of the Teton Range. It is a terrain of glaciated and eroded mountain crags, conifer forests, and open, rolling meadows, with the Snake River twisting through it all.

Berger, a conservation biologist from the University of Nevada at Reno who also conducts research for the Wildlife Conservation Society, is in the middle of researching a current environmental drama, and he dresses like a moose to do it.

For some 50 years, the two main predators of moose--wolves and grizzlies--have been absent from the southern portion of the Yellowstone ecosystem, extirpated by humans. Since the reintroduction of wolves to Yellowstone over the last two years, the critters have gradually been drifting south, and they will soon recolonize this area. Coincidentally, grizzly bears are also slowly moving south to recolonize the same area. Berger suggests that perhaps the grizzly population is increasing or that the great Yellowstone fire of 1988 has forced them to seek more fertile grounds. Whatever the cause, the result is that very soon, sometime in the next couple of years, moose are going to be in for a rude surprise. The question for Berger is, how rude?

Fascinated, I needed to know more: With the relaxation of predation as an evolutionary selection pressure, to what extent do prey-- the moose--retain the ability to recognize past predators? Is the fear of predators genetically hard-wired, or is it an acquired phobia, passed on from one generation to the next? If the latter, then--oh, who am I kidding? I had the chance to watch a grown man walk around in a moose suit. The guy could’ve been studying his fingernails for all I cared.

Now, why the suit? After all, short of some maniacal inclination to harass large animals, why would anyone want to dress like an ungulate, go tromping through the snow in near-zero weather, and sidle up to long- legged, big-hoofed, short-tempered mammals? Simple. Berger has to get close enough to lob snowballs full of urine and feces at ’em, that’s why.

Okay. Perhaps more context is in order. To gauge whether moose innately recall predators, Berger throws scat balls (along with the appropriate--and here’s a phrase I’ll bet you haven’t heard lately-- control feces) to see if the animals react to the scent. He also blasts them with predator sounds using a portable stereo (more on that later). Now, Berger has a good arm, but he’s no Roger Clemens. To sneak close enough to the moose to make the throw, he needs the suit, made for him by a local resident, one of the costume designers for the original Star Wars film. Once in range, he brings an arm out from under the suit and pitches the fecal ball. He then gauges the reaction of the moose, which could range from none at all to a disruption in its normal feeding rate to an all-out run in a blind panic, screaming for its life.

What he’s found to date is that moose in the Jackson Hole area don’t react to the scent of wolf but do react to the smell of grizzlies. (In case you’re wondering, Berger obtains his grizzly feces--Hey Harry, guy here wants us to mail him some fresh bear crap!--and his lupine urine from the Grizzly Discovery Center in the town of West Yellowstone, Montana.) Berger thinks this adaptation by the moose--literally forgetting a predator because of relaxed predation--may be rapid, occurring over as few as 10 to 15 generations, or 50-60 years.

To check his findings, Berger has performed the same scat-ball experiment in predator-rich Alaska, where wolves and grizzlies have continually preyed on moose. There he finds the opposite reaction, at least to wolves: moose feeding rates drop when they get a whiff of wolf whiz. As to the common reaction to bear, Berger speculates that moose may simply have a stronger recognition of grizzlies. Interestingly, he’s found that the Jackson Hole moose also react to the odor of Siberian tiger scat (obtained from the Anchorage Zoo).

Remember, all the hoofed mammals except the pronghorn came to North America over the Bering Strait, so moose were hunted by tigers at some point, Berger says. It could be that tigers and grizzlies were more efficient hunters, and the memory of that was simply imprinted more strongly on the moose. Then again, it’s way too early in the research to be sure.

The moose suit is actually made up of two pieces; usually Berger wears it with his wife and research partner, Carol Cunningham. He’s up front, wearing the tall head, complete with black button eyes, pendulous muzzle, and plush ears. Cunningham has to bend at the waist and drape brown, woolly cloth around herself to imitate the moose’s body. The costume comes down to waist level, leaving the couple’s legs exposed. Apparently moose aren’t very discriminating about whom they hang with. To get around, Berger and Cunningham must coordinate the movement of front and rear--not an easy task, what with four legs breaking through deep snow at different times.

I meet Berger for a few hours the first day I arrive. It’s very cold (the temperature 2), overcast, with snow expected. After renting snowshoes in the aptly named hamlet of Moose, we drive a few miles north and go for a stroll. Berger leads, carrying moose head, small backpack, and a ski pole for balance, easily scrambling up a steep snow embankment. I follow, doing a graceless duck waddle on my snowshoes. At the top I let out an involuntary shout of appreciation. From there I can see, with the Tetons as a backdrop, a panorama of mammals. Directly ahead are two groups of moose grazing on willow twigs--wood--their basic winter diet. Stage right is an elk herd, some grazing, some lying down. Far right is a lone elk, grazing and seemingly unconcerned that, some 50 yards beyond, three or four coyotes are contemplating it, licking their collective chops. All that’s missing is Rocket J. Squirrel and Mr. Peabody. Berger grins and says, Regular savanna, huh? He’s looking for a particular cow and her calf, which he finally spies some 80 yards off, but they are moving away from us. Since it’s late in the day and I’m turning a robust shade of blue from the cold, we abandon the chase and head back to town.

Day 2: temperature, 2. Add in wind chill factor: I don’t want to know. As I pull up in my rental car, Berger is on the roof of his tired Volkswagen van, seemingly oblivious to the cold and fiddling with what appears to be a tv antenna. Cunningham stands nearby. The antenna is part of a radio receiver; to acquire information about moose behavior before the big bad wolves arrive, Berger has radio-collared 20 cows. One way to check the robustness of a species, he tells me, is to track reproduction rates. Berger does this by collecting two samples of each cow’s--what else?--scat. He stores them in his freezer. Once all the samples are collected, he’ll send them to a lab that will check for elevated levels of progesterone, which indicates pregnancy.

As he talks, Berger is twirling the antenna this way and that. A moose’s proximity is indicated by the strength of a beeping signal emanating from the receiver, which Berger wears like a camera, strapped over his shoulder. The stronger the beep, the closer the moose. Once they give birth, he continues, we’ll track the survivorship of the calves. (At least, I think that’s what he said, but I confess I wasn’t being as attentive as I should. Instead I was counting my appendages and idly wondering if it was possible for the water in one’s eyes to freeze.) After he’s established the direction from which the signal is coming and actually sighted a moose, Berger identifies the particular animal by a notch clipped from its ear. In winter, he tells me, when bulls have dropped their antlers, the easiest way to distinguish bull from cow is by the white patch around the female’s vulva.

Berger picks up a signal from one animal, but it’s coming from somewhere beyond the Gros Ventre River, which flows nearby. Unwilling, thank God, to ford the water to reach it, Berger suggests we pile into his cluttered van and travel north on Highway 89; up ahead, three cars are pulled over. Joining them, we see two moose grazing on willow branches just off the road. Berger decides this is as good a place as any to demonstrate the moose suit, but he wants to wait until some of the tourists, busy snapping photos, have moved on.

Berger hates attracting a crowd. Not that people are annoying, he says, straight-faced, but I’ve been reprimanded by park rangers for creating a traffic hazard. He goes to great lengths to stay on every ranger’s good side, but as I’ll see, dressing like a moose and maintaining a low profile are mutually exclusive. Meanwhile, Berger makes his preparations. He reaches for what appears to be a water bottle, then curses. Damn, he says, the wolf urine is frozen. Sure enough, the plastic bottle is bulging, making it look like a urine hand grenade. Since Cunningham has to leave shortly for work (she works part-time as a biologist for the National Park Service), Berger decides to go ahead and demonstrate the moose suit anyway.

At last the tourists leave and the pair suit up. Berger looks huge in the moose head; it towers a good two feet over his 5 foot 11 frame. Cunningham, though, has the harder part. Wearing a small backpack to give body to the body, she must walk crouched over, unable to see. The pair now march down the highway, slightly sideways, to approach the moose from the side. A car approaches, then stops in the middle of the road, the occupants inside staring. Next, a bus full of Japanese tourists drives by; even though I can see much exclaiming and pointing of fingers, the bus passes and doesn’t stop until it’s a full quarter mile down the road. Then it begins backing up. Last, another car approaches from the opposite direction, also stopping in the lane. Now the road is blocked in both directions, and a large, noisy bus filled with excited Japanese tourists is backing up the highway.

With all the commotion, one moose wisely bolts, clambering over a fence and heading off in an ungainly trot. I swear that as it ran it kept glancing over its shoulder with a What the hell? expression at Berger and Cunningham. After several more minutes, as the pair slowly struggle in the deep snow to move closer to the remaining moose, the two cars and the bus, its occupants apparently easily bored, finally pull away.

Moving nearer to improve my vantage point (I’d brought along a camera), I’m mortified when I apparently startle the last moose, which turns suddenly and walks away. Berger politely suggests I stand still next time and that it might be better to find a more secluded spot to demonstrate the suit. As we drive around, Berger stopping occasionally to do a radio check, I ask the pair what their most embarrassing moment with the moose suit has been.

Actually, the most embarrassing moment didn’t happen when we had the moose suit on, Cunningham says, but when we were tracking with the radio receiver. When a moose is killed, the rhythm of the radio signal will change to mortality mode, alerting the researchers (the signal changes when the collar stops detecting motion). Berger and Cunningham picked up such a signal when standing high on a bluff well outside Jackson Hole. But the closer they got to town, the stronger the signal became. Until finally, we were in town, walking down the sidewalk, Joel holding the antenna in front of him, people staring and stepping to the side to let us pass. You can imagine the comments. It turned out that a biologist had found the dead moose, removed the collar, and took it back to his office. The pair eventually found their way to his front door.

Later, after driving down a deserted side road, pushing our way through deep snow and protruding underbrush, and gingerly walking on a frozen stream, we give up, only to see three moose appear, popping up not 50 yards from us, coming out of the woods to stand in the center of the road.

Berger and Cunningham quickly don the moose suit and begin moving quietly toward the trio. This time I stay well back, camera in hand. The pair get almost into throwing range (had, of course, the urine been throwable) when a white van comes up alongside us. Two of the moose hesitate for a second, then jump into the deep snow on the side of the road. The driver, without batting an eye at Berger and Cunningham, slowly drives straight toward moose number three, which stands its ground for a moment, then turns and begins running at a dogtrot, so to speak, up the road. For at least a quarter mile I watch as the moose refuses to yield, jogging just ahead of the van, glancing back over its shoulder, until both disappear around a corner.

As Berger starts to remove his head, a pickup truck pulls up and stops. This shy guy leaps out of his truck, laughing, with his camera. He begs Berger to put the head back on so he can take a picture. Berger complies and the guy takes a shot or two (while I take a picture of the guy taking a picture) before finally leaving.

The pair come up. It was the fastest way to get rid of him, says Berger.

Did he even ask why you were dressed like a moose? I ask.

No, says Cunningham, shaking her head. He just asked where we were from.

I told him we’re tourists from Nevada, Berger says.

I later wonder out loud if the moose ever get confused when they see the suit.

It’s possible, says Berger. A couple of times I’ve taken off the head and tossed it up and down in the air to see their reaction. They just stare.

Usually, when we make an approach to place the urine, I do it very slowly, he adds. It takes me at least a half hour. I’ll stop and dip my head, pretending to browse. This demonstration today is pretty artificial; usually moose don’t stride right up to other moose.

We spot more moose. Berger pulls to the side of the road to show me his stereo system. Besides throwing predator excrement at moose, he plays life-threatening sounds to see whether the moose react. Using a portable tape player and loudspeaker, Berger plays sounds of wolves howling or ravens cawing. Why ravens? Since they are scavengers, Berger suggests that their caws may attract carnivores as well, bad news for moose. Again, Berger gauges a reaction by timing how long the animals stop feeding. (Also, as a control, he plays nonthreatening sounds like water running or insects buzzing.) Once again, he’s found that Jackson Hole moose don’t react to wolves or ravens, while the control group of moose he studies in predator-rich Alaska do.

I ask him whether the moose are likely to relearn the dangers of wolves very quickly. Berger shrugs. I don’t know, he says. That’s why I hope to run this study for five years; we’d like to find that out, but it makes sense that they would. In the meantime, though, the big losers will be the calves. Currently, the annual survival rate of Jackson Hole calves is nearly 100 percent; in predator-heavy regions of Alaska, however, carnivores consume between 60 and 80 percent of the calves each year. Fortunately, moose are one of the few large mammals in the world that are not yet endangered (unlike, ironically, their predators).

At the end of the day and my visit, it’s my turn to act like a moose. Much to my disappointment, it’s still too cold for the snow to pack. This means I won’t get to carry a snowball dripping with urine in my bare hand so I can have the once-in-a-lifetime opportunity to hurl piss at a moose. Still, I did learn that being a field biologist wearing a moose’s head is no walk in the park. (Well, technically it is, since this is national parkland, but you know what I mean.) I know this because when I tried it I found myself hung up on a tree branch while struggling to relocate the eyeholes in my twisted head. To avoid blowing the ruse, since there’s a moose nearby, I nod my two heads at some willow twigs, clumsily pretending to be eating like the real thing.

Finally, rearranged, I peer out the eyeholes, but the moose has lost interest. With a quiet snort--of derision, no doubt--it turns and slowly walks away. I take off my head, feeling not like a moose but an ass.

When you dress like Bullwinkle, you check your dignity at the door.
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