Seven minutes, and M57, the growling devil bear, was reduced to a heap of snoozing fur. Jason crawled into the trap and pulled him out; a potent wash of wolverine scent – somewhere between sweat and expensive goat cheese – drifted over the assembled crowd as we weighed him (12.4kg) and then lowered him onto the bed of water bottles and blankets. Quickly, the field crew secured M57’s feet, while Bob, Mark, and Jason slipped the oxygen mask over the wolverine’s face and fixed the pulse oxymeter to his tongue. I was trying to count his breaths, watching the rise and and fall of his chest; a moment of intense panic as it seemed that he wasn’t breathing at all. I saw Jason lean quickly forward, pushing aside the fur on the wolverine’s torso as if searching for a sign that the animal was still breathing, and then the breaths came, rapid and shallow.
M57’s initial readings were good – a temperature of 101°F, heart rate of 56 beats per minute, respiration at 48 breaths per minute, and a blood oxygenation rate that was steadily climbing as the oxygen mask took effect – so the crew took its time looking him over. He was dark, but not as dark as some wolverines; the face mask and the lateral stripe were faintly visible, the white chest patch prominent. His left front paw was entirely white, and his right front paw bore a crescent marking. Since his capture in the bobcat trap in Idaho in 2009, he’d lost two toes from his right front paw – one of these toes had been dislocated in the bobcat trap – but the wound was old and well-healed. At 12.4 kg, he was smallish for a male wolverine, but his weight was about the same as it had been when WCS had taken him to Montana, which was a good sign. Jason checked his teeth: lower left canine broken, with apparent cavity; top right incisor missing. Later, Jason said that most adult wolverines were missing teeth or had broken canines, which probably limits the lifespan of an animal that lives largely by its teeth.
Together, Jason, Bob, and Mark assessed M57’s neck, where the fur was worn slightly, presumably from the previous collar. The skin was healthy, though, with no sores or other signs of damage. Before we got on the snowmobiles to head to the trap, the scientists and field crew had held a quick meeting to decide on procedure, and there was unanimous agreement that if there was any sign of injury from the previous collar, we would release M57 without putting on a new collar. But he seemed fine
Jason, Bob, and Mark quickly fitted the collar around M57’s neck, punching holes, making adjustments, while I kept track of the vitals; all signs remained good, the temperature never dropping below 100°, but we were running out of time, with only five or six minutes left. The collar rivets tightened, Jason asked for the list of measurements that we were supposed to take, and I read them off from the capture form. Total length: 109 cm. Tail length: 24 cm. Chest girth: 44.5 cm. Neck circumference: 34 cm. Head circumference: 33.5 cm. Jason seemed impatient with some of these measurements, and thankfully cut me off before we reached the final item on the list: circumference of testes. Noting that they were descended was apparently adequate for our purposes (we had high hopes that he and the resident female wolverine, F3, had mated. The two had been spotted within a mile of each other a few days previously, and both were around 4 years old, the perfect age to start reproducing. In the circumstances, knowing that he was capable of fathering kits was a crucial point; the precise parameters of his capacity seemed less important. Back in the office in Jackson, reviewing the forms, I asked Jason what the circumference of testes indicates within the context of wolverine biology, and he thought for a second, and said, “No idea.”)
We untied the wolverine’s paws and gently flipped him onto his stomach so that we could check for parasites. Time was running out, and suddenly M57 shuddered and began to growl, this time an outright snarl that seemed much less placid than his rumbling in the trap. This was the signal that the procedure was at an end. Keeping a firm hold on the animal’s head, Jason lifted him, one of the field crew quickly injected M57 with a drug reversal, and the crew snapped a few fast photos. By the time Jason and M57 reached the trap, M57 was struggling, and Jason lowered him carefully into the interior and then the lid came down.
That was it. We would wait for two hours to make sure that the drug had been fully metabolized before we released him. Most of the crew headed out, and those who remained tidied up the supplies, loaded them back into boxes and backpacks, and rehashed the evening in hushed voices. We spent some time looking at the tracks around the trap, and Jason mentioned that M57 had traveled to the trap following the exact same route that F3 habitually took. No one was sure what this indicated. Wolverines have a reputation for being solitary, but biologists suspect that they are more social than we’ve previously believed, and there’s speculation that male wolverines play a larger role in raising their kits than we realized. M57 and F3 had been in close proximity to each other a few days before M57 was captured, and they’d been spotted in similar proximity over the summer. It was difficult not to spin off into wildly anthropomorphic tales of a budding wolverine family. February is denning season, and if F3 was pregnant, she would have just given birth.
Periodically, we lifted the trap lid to check on M57. First he was asleep, curled up where Jason had placed him. Twenty minutes later, he was sitting a few feet from the mouth of the trap, staring but not growling. Later, he was pressed against the mouth of the trap but still seemed woozy. We closed the lid again, sat or leaned against the couch, watched the snow drift down. A pair of eyes, caught in the beam of the headlamp, glowed piercingly green against the night, coming down the path towards the trap, and for a second my heart thudded and my head went light; I was convinced it was F3 (A momentary diversion, the thought of a wolverine marital dispute: “Where have you been? Oh, you were kidnapped by aliens, that’s a likely story! You’re acting completely stoned. Are you high? My god, we have infants back at the den!”) Then a second pair of eyes appeared, and when we pulled out a flashlight, two martens stood still for a second in the beam before scampering into trees. Their eyes blinked at us from around the trap; first uphill to the left, then on the path again, then off to the right. They were after a chunk of bait that was hung from one of the trees. They huffed and circled and seemed momentarily confused by the sudden presence of people at what was clearly a habitual nightly feast, but, being weasels, they quickly decided that we weren’t a threat. The director of the field crew showed us a video, on his cell phone, of a marten they’d caught in one of the traps earlier in the winter; the animal, weighing in at around five pounds, seemed twice as aggressive as our wolverine, snarling, growling, screeching, and throwing itself towards the camera.
“You’re twenty, thirty times its size, and it still wants to take you,’ said the field crew director, ” Amazing.”
The green eyes glowed at us from the tree, and then from the bait, while the field crew director frowned. The bait was suspended several feet from the trunk of the tree to prevent scavengers from getting to it, but the martens were regularly able to pillage the supplies, and no one was sure how they were doing it. Now, in the beam of the flashlight, we watched them walk the suspension wire as if it was a tightrope. The field crew director shook his head. “They’re on the wire,” he said, “Amazing.”
The martens animated the night, and the shockingly brilliant glow of their eyes, here and then gone and then reappearing someplace completely new, conferred a sense of living intelligence, as if the ecosystem itself was watching us watch it.
At midnight, we checked M57 again, and he was growling and pacing once more. Jason propped open the trap lid and we stood back on the slope of the hill overlooking the trap, cameras poised, waiting. And waiting. And waiting. My camera batteries died in the cold, but I didn’t dare move to retrieve my smaller camera. Finally, M57 poked his head out of the trap, tentatively. He turned to look at us, and then retreated. We waited. For the first time that night, my toes were beginning to feel cold. I didn’t dare stamp my feet or do anything other than curl my toes inside my boots.
M57’s head emerged again, and again he turned to look at us, a long, flat stare. He’d been in the trap for hours, and for all of that time, danger had approached from the very place that we were now expecting his to use as an exit. He put his front paws on the lip of the trap, stretched up, and looked out towards the forest, then back at us. He stood like that for a long time before finally climbing out of the trap and, with one last look at us on the hill, dashing away. Except that he had run directly into the maze of the operating theater, where the crew had dug a series of high-walled passages into the waist-high snow. We stayed still, and a few minutes later M57 reappeared, looking chagrined, trying to find a way out of the passage. He climbed one wall, turned to stare, then zigzagged towards the pines. He looked huge against the snow as he ran. He suddenly stopped, turned in two tight circles, rolled over and over on his back. Then he stood up, and moved into the pines, crested the hill opposite, and disappeared.