Wolverines are badass animals. That’s probably why Marvel Comics made a character based on them. But unfortunately, we know more about the comic character than the real deal! Myth tells us that these animals are enormous gluttons, so much so that their latinized name is Gulo gulo, which means glutton glutton. I suppose the double name speaks to the intensity of glutton they were once thought to be.
Wolverines are a modest sized animal that can weigh anywhere from 15 to 70 pounds, with most being in the 30-50 pound range. They have the lithe muscular bodies of young black bear cubs, but with the wide digging-ready paws of a badger. Their heads look like a mashup of a Tasmanian devil with a mongoose. They have enormous strength that allows them to gallop for hours on end through deep snow fields, swim through freezing streams and rivers, and haul their bulk up nearly vertical cliff faces. And did I mention their skulls harbor bone-crushing teeth? Well, they do, and they make good use of them, gobbling up bones from carrion and fresh kills alike to process the fatty, nutritious marrow that many other animals can’t access.
Despite their obvious badassery, wolverines have remained one of the most understudied mammalian predators on the continent.
A few years ago, a multi-year project to study the life history details of these animals was undertaken at Glacier National Park, where a small population of the animals still remain. The study provided the perfect vehicle for Douglas Chadwick, who volunteered on the project, to write a book about these amazing but largely unknown carnivores.
In The Wolverine Way Chadwick narrates the time he spent as a volunteer on the Glacier project. His voice offers a mix of wonder and humility with just the right amount of swagger. But that last element stems almost solely from what we learn of wolverines: how they can scale sheer rock and ice mountain faces in times that make the most ardent mountaineers green with envy; how they can roam twenty or more miles across rugged topography in a single day, treating mountain slopes as if they were flat; how they can go head-to-head with grizzlies to stake a carcass as their own; and how they can munch bones like so many stale breadsticks to carry them between meaty meals.
Chadwick’s engaging, at times poetic, writing and reflections of the natural world are what elevates this book from a mere documentation of a project to an insightful tome into what I can only call the mindset of a wolverine. Check out this video trailer to see what I’m talking about:
In the past week, I’ve seen snow flurries on Nags Head beach, whale spouts puffing within a half-mile offshore and gangly white tundra swans careening through the air. But the highlight was watching a pack of endangered red wolves scramble into the woods.
I’ve been working on more book research, and spent a few more days with the red wolf biologists. They are heavy into their winter trapping efforts, part of which entails trying to capture the puppies born in March and April of 2010. By now, the pups are large enough to receive a radio collar.
Collaring the young of the year is essential. When they are born, the biologists try to tag all of the red wolf pups with passive integrated transponder chips, rice-grain-sized chips they inject under their skin. When scanned with a radio-frequency ID device, the chips emit a unique radio signal. But they don’t broadcast a unique signal like the radio collars do. So between the time the pups are born and tagged, and winter trapping eight months or so later, the biologists essentially have a data blackout on them. They set soft-catch leghold traps to capture the pups, and then take them to a processing facility where they fit them with collars, and give them vaccines against things like rabies and heart worm.
To reduce re-trapping the same animals from a pack’s home range, sometimes the biologists will take the trapped animals and hold them a few days, hoping that within that time they will capture the other targeted animals in that area. This past week, I was lucky to witness a breeding female and three of her four pups returned to their home range. The biologists I was shadowing loaded them up into their trucks and drove to the wolves territory. (more…)
Is it a red fox on stilts or an elegant, long-limbed wolf with a fox’s face? If you find yourself face-to-face with a maned wolf, then you can be forgiven for having these questions run through your mind. Maned wolves are a South American canid that are not in the genus Canis, but rather in the related genus Chrysocyon. For a truly vivid account of a maned wolf encounter, click on this BBC Program, Saving Species, then click on the “Listen Now” option for episode 31. The program is about 30 minutes long, but around 18 minutes and 30 seconds is a segment on the maned wolf. The narrator visits a monastery in Brazil where maned wolves emerge from the surrounding forest to take strips of meat right out of a priest’s hands. The first part of the story is a whispered affair where the narrator tells listeners about two maned wolves approaching the monastery for food. His descriptions are first rate. The second part talks about maned wolf habitat threats (agriculture and clearing of grasslands and woodlands). This second portion features an interview with Claudio Sillero, a canid conservationist at the Univ. of Oxford in the zoology department and chair of the IUCN Canid Specialist Group. Enjoy.
If I could use only three words to describe The Wolf’s Tooth, these are the ones I’d choose: elegant, forceful and fluid.
This is a story about how two intertwined ecological concepts — keystone predators and trophic cascades — leave their signatures upon entire landscapes. The Wolf’s Tooth is authored by Cristina Eisenberg, a PhD candidate at Oregon State University who studies conservation biology. Before graduate school, she was a journalist and editor. Her dual career paths collide in The Wolf’s Tooth, and the result is a remarkable and timely story about her own research but also an entire mountain of literature that came before her.
Before I go on, some definitions may be helpful. Trophic cascades are a phenomenon whereby reactions cascade through a trophic web, or food web. Because trophic webs are really giant networks that process energy and nutrients through an ecosystem, when something causes a glitch or a change in the system it ripples through to other levels. Eisenberg studies this concept with a focus on the interactions between reintroduced gray wolves, elk and aspen and willows. This is a three level trophic web, where the wolves eat the elk which eat the aspen and willows. In this system, the wolves would also be known as a keystone species. By definition, these are carnivorous species that are the glue that bind their ecosystem together; without them, things have a tendency to fall apart or shift dramatically. Keystone species exert a disproportionately strong influence on the other species in their systems. For example, in the very real case of wolves being extirpated from Yellowstone National Park, the elk population swelled to great numbers and then ate the aspen and willow stands down to the point that new trees were not growing into mature trees because of over-browsing.
To tell the story of trophic cascades and how we know what we do about them, Eisenberg weaves fluid first-hand accounts of her PhD field work and personal experiences in nature with summaries of foundational studies. Her own field work entailed monitoring aspen and willow stands for herbivory patterns from elk, and correlating these patterns with the presence or absence of wolves and predators in the area. The scenes she bases on her field work transport the reader to the slopes and valleys she worked in Glacier and Yellowstone national parks, the H. J. Andrews Experimental Forest in Oregon and elsewhere. As a reader, you experience what she does: you discover a coyote carcass with its throat torn out by wolves, clear evidence of a territorial dispute; you tiptoe through a den site littered with the chew toys of wolf puppies; and you feel the hair on your neck raise when a moose is taken down by wolves only a few hundred yards from Eisenberg as she’s wrapping up a transect line. The sheer force of her narratives thrust you into the journey she’s embarked upon to understand how species interact in the web of life. (more…)
Just how many sub-species of American martens are living in California and Oregon? Well, there may be one less than experts thought, according to a 2009 study published in Conservation Genetics.
American martens (Martes americana) are slightly larger than a house cat and are carnivorous members of the Mustelid family. They live in boreal forests and are widely distributed across Canada, but they are also found in mountainous and coniferous forested areas in Washington, Oregon and northern California, as well as south through the Rocky Mountains to northern New Mexico. While the populations in Canada are largely contiguous due to the comparatively more intact forests there, populations in the U.S. tend to be fragmented. This is in part due to the animals moving into what’s called Pleistocene refugia — areas where the climate is more akin to the cooler, drier times of the Pleistocene, which are generally areas of higher-elevation — and also in modern times, habitat encroachment such as logging and development.
American martens also prefer mature forests, and much of the old-growth forests have been cut down. If memory serves, about 5 percent of our original old-growth forests remain here in the U.S. Because they are so tied to these dwindling habitats, and because they were historically over-trapped for their fur, the species has been on conservationists’ radar screens. (more…)
This video from BBC Earth shows spotted hyenas out-competing a small pride of lions to claim the remains of their kill, including the juicy and nutritious bone marrow. Spotted hyenas are not just scavengers, they are also formidable predators in their own right. One of my most popular posts on Wild Muse is about the quirky genital mimicry of female spotted hyenas.
Spring comes to the northern Rocky Mountains like a lion and often leaves like one too. This spring proved no different. I spent it in Waterton, Alberta, resampling eighty miles of track transects I had created three years earlier, looking for changes in wolf and elk use of this critical wildlife corridor. My study area in Waterton-Glacier International Peace Park spans the US-Canada border and harbors most wildlife species present at the time of the Lewis and Clark Expedition.
Track transect surveys are among my favorite fieldwork, because this method allows me to experience landscapes intimately. Walking along the same pathways that wolves and elk use, I pull measuring tape in fifty-yard increments and record all the large mammal animal sign I find along a two-yard strip on either side of the tape. Along the way I often find unexpected and fascinating things and secret places—coyote dens, wolf rendezvous sites, a newborn elk bedded in the shrubs, and the place where a grizzly sow has lain with her cubs. However, this method can only be applied between snowmelt and when the grass grows tall enough to hide the data (wolf and elk droppings, carcass pieces). This May, five snowstorms made our work more challenging than usual, effectively burying my data and immuring us in our quarters for days. (more…)
Suburban Howls: Tracking the Eastern Coyote in Suburban Massachusetts is a documentation of research on coyotes done by Jon Way while he was at Boston College and earning a PhD. He tells anecdotes about coyotes he caught during the multi-year study of coyotes in Boston and its surrounding suburbs as well as Cape Cod; and he tells anecdotes about the frustrations of working in an urban area. While it’s fascinating to learn about the life histories of the animals he studies, it’s equally heartbreaking to learn about their deaths at the hands of hunters, drivers of cars, and in one rare case a poisoner.
Way’s writing is at times detached, in the way you might expect a wildlife biologist to discuss their animal subjects. But these moments are few and far between. The bulk of the book is emotionally charged. It’s a rare look into the inner mind and emotions of a scientist going about his research. He’s not shy at disclosing snags he hit with the Massachusetts state wildlife agency and a zoo he was initially partnering with. (more…)
An Indiana bat, at a western N.C. cave. (Photo by Gabrielle Graeter, N.C. Wildlife Resources Commission)
One of the worst wildlife die-offs in recorded history is unfolding in caves and mines throughout the north- and southeast. A disease dubbed white-nose syndrome is killing off bats at a mortality rate that, at some sites, approaches 100 percent. Bats infected with the fungus thought to cause the disease awake early from hibernation, or don’t slumber as deeply as they should, and burn through their fat reserves too fast. They emerge from their caves before winter has ended and then starve for want of insects. To save energy, bats shut down their immune systems during hibernation, which makes them even more vulnerable to the illness in winter. (For more on the specific mechanisms of how the fungus may sicken and kill bats, see my previous post, “Warming caves, a stop-gap measure to thwart WNS?”)
I first wrote about white-nose syndrome at the Science in the Triangle blog (Hibernation Devastation) after attending a lecture about the status of the disease in December 2009. (That post was later reprinted in The Naturalist, a publication of the N.C. Museum of Natural Sciences.) Tomorrow, 9/6, my second published story on white-nose syndrome will run in the Charlotte Observer’s Sci-Tech section, as well as in its sister paper, the Raleigh News & Observer. But you can find it online, tonight, here. As always, there is never enough space in the print edition to include all the cool things gathered, and reported on, when writing the story. So I’m making this blog post a grab-bag of the parts that got cut or that I researched but did not have space to include. (more…)
Chrysocyon brachyurus, maned wolf, in Cologne Zoo, Germany. (Wiki Commons, image by sarefo.)
How can you conserve a large carnivore when you don’t know how many of them exist? It’s a difficult task, and so a few scientists at the Jaguar Conservation Fund opted to put a number on their target population… only it’s not jaguars they were trying to pinpoint, it was the lesser known maned wolf.
The maned wolf is a quirky-looking wild dog relative that looks rather like an over grown red fox whose legs have been comically elongated. Or a skinny wolf on stilts. Though it is in the family Canidae, it’s not in the genus Canis as are true wolves… rather, it is in a related genus and is named Chrysocyon brachyurus. My reading of Tedford and Wang’s book, Dogs: Their Fossil Relatives and Evolutionary Origins, indicates that these researchers believe the South American canines, including Chrysocyon, evolved from a group closely related to, but separate from, Canis.
Today, the maned wolf lives in Brazil, Paraguay, eastern Bolivia and northern Argentina where mated pairs maintain territories from 30 to 80 square kilometers, according to the study. But the pairs do not hunt together, rather they go after prey individually. The largest portion of the animals range lies within Brazil in what’s known as the Cerrado or Brazilian savannah. This area is being rapidly converted to cattle ranches and agriculture, the authors state. (more…)