Unless you’re very familiar with plains-dwelling animals, you’d probably never peg the Richardson’s ground squirrel as a relative of the red squirrel or the grey squirrel. These mammals look much more like gophers or small prairie dogs. And they behave more like both: “ground squirrel” is an incredibly apt common name given how much of their lives these critters spend underground! (It’s a lot—see below.)
Ground squirrels vs. tree squirrels
The species was named after the Scottish naturalist Sir John Richardson. Looks-wise, they have larger bodies but much smaller tails than their tree squirrel relatives. (Tree squirrels need bushy tails to help with balance.) A ground squirrel’s skinny tail is almost constantly twitching, like a tiny whip—it’s one reason why they’re nicknamed “flickertails.” Their ears, meanwhile, are so flat that they appear mashed into either side of the head.
When do they hibernate?
The Richardson’s ground squirrel spends up to eight months hibernating. Adults emerge from their dens—in Canada, dug into open meadows and plains in the prairie provinces—between February and March. They return underground by mid-June at the latest. Juvenile squirrels spend a little less time in hibernation—between five and seven months. But even when the squirrels are not hibernating, they’re still only aboveground for eight to 10 hours of the day. An individual Richardson’s ground squirrel spends a mere 15 per cent of its existence on the surface. (Imagine living 85 per cent of your life in the basement.)
Ground squirrel dens provide digs for other prairie dwellers
Richardson’s ground squirrel burrows play an important role in the lives of other denning creatures. Mice, voles, burrowing owls, badgers—they enlarge the holes to suit their bigger bodies—plus salamanders and invertebrates repurpose empty dens. Even bumblebees nest in ground squirrel homes.
When do ground squirrels reproduce?
Squirrels mate soon after they emerge from hibernation in early spring. Females all give birth around the same time, so the population explodes all at once. But it can crash just as quickly: mortality is especially high with this species, thanks to prairie predators such as hawks, falcons, eagles, weasels, and rattlesnakes. About 50 to 70 per cent of babies don’t live long enough to reproduce (at about a year old). Despite this, it’s common to spot both adults and babies in Manitoba, Saskatchewan, and Alberta—at least, it’s more common to spot them than it is to spot other grassland mammals. They’re bold, and will happily approach people, looking for handouts. Cheeky!
I have studied coyotes and other wild canids for over 30 years. Co-existence with coyotes is possible. My understanding comes from many places: being a care-giver to orphaned coyote pups, studying the development of coyote play and communication, helping trap and radio-collar them, supervising multiple theses and, most recently, monitoring a multi-generational coyote family for years. I interact with coyotes at very close range, and sparingly use aversive conditioning, which involves using my voice, body, and a held object to establish boundaries.
Distorted risks
I am often asked how citizens can protect themselves against “aggressive coyotes.” In my research, I found that coyotes rarely exhibit aggression, but human fear of coyotes is pervasive and overrides scientific evidence. While sometimes unintended, the use of risk narratives (including misplaced words like bold, aggressive) by scientists or media has the demonstrated effect of tapping into existing fear—this is referred to as the “social amplification of risk.”
People then normalize the idea that coyotes are likely to attack, rather than the more apt narrative: Coyotes are simply trying to survive, preferring to avoid people. When coyotes react, it is to protect themselves, their mates or pups from an actual or perceived threat, like dogs chasing them or coming into a den area, or a person poking at the den with a stick. In the reports that I have reviewed where dogs were attacked, over 90 per cent involved dogs off-leash and at-large.
Coyote reactions stem from context and experience, they are varied and rarely about aggression. Habituation in cities may have led to delayed or less dramatic responses in coyotes, as compared to non-urban coyotes that often desperately flee from humans.
Living in the city
Conflict with coyotes is preventable, but when it occurs, it does so in the context of several human-centred factors. Habituation of coyotes is often the first identified culprit. This means that the coyotes become accustomed to human activities, learn to “tune them out” and direct attention to those things that are more important, like finding food.
In wildlife observational research, scientists often strive for animal habituation so the observer may be in plain sight, yet “invisible,” allowing animals to do what they do. In the absence of immediate threats, coyotes learn to sometimes disregard humans.
Habituation may lead to proximity issues, which can cause conflict if it is coupled with food conditioning—the intentional or unintentional feeding of coyotes. This arises when people fail to keep yards free of food attractants like dog food, bird seed, fallen fruit, or compost. A coyote learns to depend on that food source, which can can increase the risk of the coyote guarding food against people and pets.
What is most catastrophic to co-existence is when people decide to deliberately feed coyotes. That often is a death sentence for the coyote because it can eventually demand food. Coyote demand behaviour may include a coyote latching on to a person’s clothing or limbs in an attempt to get food, and can be mistakenly classified as aggression or attack. Once a coyote has bitten a person, the chances of rehabilitation are low relative to the risk of escalation, and a coyote exhibiting this behaviour would likely be killed.
Several studies about coyote diet in Calgary, conducted in my lab, showed less than two per cent of samples contained pet remains. Coyotes are not fully to blame: the city has a bylaw prohibiting free-ranging pets, which many people disregard, subjecting their pets to possible death by owl, eagle, bobcat, domestic dog, coyotes and vehicles. Coyotes often just scavenge, earning them the label “nature’s clean up crew.”
Dog encounters
Coyote parents are very defensive of their pups, who are born around early April. (Shutterstock)
Coyote pups are usually born around early April, known as denning season, and coyotes shift into pup-guarding mode. As a result, there can be a spike in conflict between dogs and coyotes, almost exclusively due to a perceived intrusion by a domestic dog.
Coyotes may first warn by standing and staring, this will increase to vocalization, a bluff charge, then an attack on the dog if the owner does not withdraw immediately.
Coyotes in non-urban situations might prefer certain den characteristics (for example, south-facing slopes), but in fragmented green spaces that dot cities, coyotes may be forced to be resourceful—and the more disturbed they are by people or dogs, the more prone the coyotes are to move pups somewhere perceived to be safer.
Last year at one study site, I observed hundreds of people a week, many with dogs, walked right past a father or mother coyote with four pups less than 30 metres away. The parent coyotes were measured, careful and avoided conflict routinely. Over the course of thousands of possible interactions that summer, there were six reports of “aggressive” or “bold” coyote interactions. In these rare cases, a parent coyote either escorted, bluff charged or vocalized to repel dogs that were allowed to wander in closed areas—there were no attacks or injuries.
On the University of Calgary campus, we have a peaceful wildlife co-existence program, based on monitoring and investigation, education, enforcement, and mitigation. With the help of supportive staff and faculty, responsive deployment of signage or closures, removal of attractants and the measured use of humane aversive conditioning, our program ensures coyotes and surrounding communities continue to use the campus safely, promoting biodiversity and sustainability in the urban ecosystem.
I have studied coyotes and other wild canids for over 30 years. Co-existence with coyotes is possible. My understanding comes from many places: being a care-giver to orphaned coyote pups, studying the development of coyote play and communication, helping trap and radio-collar them, supervising multiple theses and, most recently, monitoring a multi-generational coyote family for years. I interact with coyotes at very close range, and sparingly use aversive conditioning, which involves using my voice, body, and a held object to establish boundaries.
Distorted risks
I am often asked how citizens can protect themselves against “aggressive coyotes.” In my research, I found that coyotes rarely exhibit aggression, but human fear of coyotes is pervasive and overrides scientific evidence. While sometimes unintended, the use of risk narratives (including misplaced words like bold, aggressive) by scientists or media has the demonstrated effect of tapping into existing fear—this is referred to as the “social amplification of risk.”
People then normalize the idea that coyotes are likely to attack, rather than the more apt narrative: Coyotes are simply trying to survive, preferring to avoid people. When coyotes react, it is to protect themselves, their mates or pups from an actual or perceived threat, like dogs chasing them or coming into a den area, or a person poking at the den with a stick. In the reports that I have reviewed where dogs were attacked, over 90 per cent involved dogs off-leash and at-large.
Coyote reactions stem from context and experience, they are varied and rarely about aggression. Habituation in cities may have led to delayed or less dramatic responses in coyotes, as compared to non-urban coyotes that often desperately flee from humans.
Living in the city
Conflict with coyotes is preventable, but when it occurs, it does so in the context of several human-centred factors. Habituation of coyotes is often the first identified culprit. This means that the coyotes become accustomed to human activities, learn to “tune them out” and direct attention to those things that are more important, like finding food.
In wildlife observational research, scientists often strive for animal habituation so the observer may be in plain sight, yet “invisible,” allowing animals to do what they do. In the absence of immediate threats, coyotes learn to sometimes disregard humans.
Habituation may lead to proximity issues, which can cause conflict if it is coupled with food conditioning—the intentional or unintentional feeding of coyotes. This arises when people fail to keep yards free of food attractants like dog food, bird seed, fallen fruit, or compost. A coyote learns to depend on that food source, which can can increase the risk of the coyote guarding food against people and pets.
What is most catastrophic to co-existence is when people decide to deliberately feed coyotes. That often is a death sentence for the coyote because it can eventually demand food. Coyote demand behaviour may include a coyote latching on to a person’s clothing or limbs in an attempt to get food, and can be mistakenly classified as aggression or attack. Once a coyote has bitten a person, the chances of rehabilitation are low relative to the risk of escalation, and a coyote exhibiting this behaviour would likely be killed.
Several studies about coyote diet in Calgary, conducted in my lab, showed less than two per cent of samples contained pet remains. Coyotes are not fully to blame: the city has a bylaw prohibiting free-ranging pets, which many people disregard, subjecting their pets to possible death by owl, eagle, bobcat, domestic dog, coyotes and vehicles. Coyotes often just scavenge, earning them the label “nature’s clean up crew.”
Dog encounters
Coyote parents are very defensive of their pups, who are born around early April. (Shutterstock)
Coyote pups are usually born around early April, known as denning season, and coyotes shift into pup-guarding mode. As a result, there can be a spike in conflict between dogs and coyotes, almost exclusively due to a perceived intrusion by a domestic dog.
Coyotes may first warn by standing and staring, this will increase to vocalization, a bluff charge, then an attack on the dog if the owner does not withdraw immediately.
Coyotes in non-urban situations might prefer certain den characteristics (for example, south-facing slopes), but in fragmented green spaces that dot cities, coyotes may be forced to be resourceful—and the more disturbed they are by people or dogs, the more prone the coyotes are to move pups somewhere perceived to be safer.
Last year at one study site, I observed hundreds of people a week, many with dogs, walked right past a father or mother coyote with four pups less than 30 metres away. The parent coyotes were measured, careful and avoided conflict routinely. Over the course of thousands of possible interactions that summer, there were six reports of “aggressive” or “bold” coyote interactions. In these rare cases, a parent coyote either escorted, bluff charged or vocalized to repel dogs that were allowed to wander in closed areas—there were no attacks or injuries.
On the University of Calgary campus, we have a peaceful wildlife co-existence program, based on monitoring and investigation, education, enforcement, and mitigation. With the help of supportive staff and faculty, responsive deployment of signage or closures, removal of attractants and the measured use of humane aversive conditioning, our program ensures coyotes and surrounding communities continue to use the campus safely, promoting biodiversity and sustainability in the urban ecosystem.
Look, it’s a black-capped chickadee! No, wait, it’s a boreal chickadee. Every Canadian can recognize the former, and its calls. But the lesser-known boreal chickadee has the same tiny body, big head, and round belly. (Adorbs.) Look carefully, though, and you’ll note the differences between the two species. The boreal chickadee has a brown cap, and darker, cinnamon-coloured sides. (Why isn’t it called the brown-capped chickadee? Good question.)
Where does the boreal chickadee live?
In North America, this songbird sticks almost exclusively to spruce and fir forests in Canada, and a few neighbouring states, such as Alaska. You can find these chickadees in almost every province, and, like black-caps, they don’t migrate (though they’ll move slightly south in the winter if there are food shortages). They prefer to feed off older trees. They’ll cling to tree cones, and poke around with their beaks to get at seeds or bugs. Their short bills are also tough enough to loosen tree bark and uncover insect eggs and larvae.
What does the boreal chickadee sound like?
The species produces a call that’s similar to its black-capped cousin’s, but it’s a little rougher and harsher, less sweet and melodic: tschick-a-dee-dee. Like other birds, boreals have all kinds of vocalizations, for alarm, warning, courtship, and aggression—everything from a low gargle to a twitter to a series of short chirps and squeals. Still, it’s a lot less chatty than the black-capped chickadee—one reason why some birders consider the boreal reclusive. And unlike our other chickadee species, the boreal chickadee doesn’t vocalize to announce its breeding territory. (For such a wee bird this can be a large chunk of real estate: up to 13 acres.) Instead, to scare off intruders, males will use a chin-up motion, or a “ruffle display”: they puff up their feathers and wings. Oh, stop frontin’, chickadee. Just kidding. We know that you’re tough.
Are they endangered?
Because boreal chickadees have a more remote and northern range than many other bird species, it’s hard for experts to monitor their numbers. Still, one survey estimated that population increased by 38 per cent between 1970 and 2017, and according to the North American Breeding Bird Survey, their numbers appear stable. So even though a lot of avian species are struggling, the future looks bright for this bird.
Zoom in and explore the northern boreal forests of western Canada on Google Earth and you’ll see long straight lines making their way through the forest. These lines are cleared trails through the forest to extract resources, creating roads for forestry and seismic lines searching for underground oil and gas deposits.
Now picture yourself faced with the task of moving across this landscape: Will you push your way through dense trees and underbrush, or will you choose to walk on the trails?
Like humans, wolves often choose the path of least resistance, moving faster and farther on human-created trails through the forest. Increased wolf movement is believed to play an important role in the decline of the threatened boreal woodland caribou—an iconic species in Canada (just look at the quarter in your pocket).
We tracked 142 wolves using GPS collars across British Columbia, Alberta and Saskatchewan—spanning over 500,000 square kilometres. The tracked wolves spanned areas with low to high prey density (measured using a metric of habitat productivity, or how much vegetation there is for species like moose), and had varying access to human-created trails.
Wolves living in areas with high densities of human-created trails took up an area roughly 20 times smaller than wolves without trails, but only when they lived in areas with low habitat productivity. Comparatively, trails didn’t change the area needed for wolves when they lived in areas with high habitat productivity.
Think about picking berries. If the berries are hard to find, you have to go looking far and wide to get enough to fill up your basket. But if something makes it easier for you to find the berries, then you don’t have to look around as much. You can just grab all the ones that you see close to you. The advantage of being able to easily find berries would be less important if there are a lot because you can skip over a few without noticing. But it becomes more important when there are few to begin with, and every last berry counts.
This is exactly what we are seeing with wolves: Instead of choosing to travel far and wide, wolves with access to lots of trails stay close to home and get by with what they have.
The space animals use to carry out their lives is called a home range, or if defended from conspecifics like in the case of wolves, a territory. If animals have smaller home ranges, that means more animals can crowd into a given space, increasing the density of that species. It is well documented that animals need less space when there is an abundance of food around—and now we know that easier access to that food can also decrease home range size. We found that increasing a wolf’s access to their prey, through things like cleared trails through the forest, can decrease their home range size, likely increasing the regional density of wolves.
Habitat restoration
But why do we care about how big wolf home ranges are? One of the biggest conservation challenges in Canada is that of woodland caribou. Caribou live across large areas, overlapping places where the energy and forestry sectors are actively extracting natural resources like oil, gas and timber.
A remote camera capture of caribou in the boreal forest. Changes in wolf-hunting patterns are threatening the already endangered caribou. (Melanie Dickie/Caribou Monitoring Unit), Author provided
Habitat restoration is imminently needed, but is expensive and time consuming. Prioritizing habitat restoration in areas where it will be most beneficial to caribou as soon as possible is necessary for effective caribou management.
Habitat restoration has two main goals: to reduce wolf hunting efficiency by limiting their use of trails and slow their movement when on them and to return the forest to caribou habitat. But now we have reason to believe that slowing wolves down can also reduce wolf density on the landscape — forcing individual wolves to take up more space and push others out—especially in low-productivity peatlands, where the effect on home ranges is stronger.
Effective habitat restoration is going to be important for moving away from other management actions like wolf management in the long term. But, we have a lot of work ahead of us. There are hundreds of thousands of kilometres of these cleared trails that need to be restored. Our study points us towards prioritizing low-productivity areas to see the biggest effects sooner.
Zoom in and explore the northern boreal forests of western Canada on Google Earth and you’ll see long straight lines making their way through the forest. These lines are cleared trails through the forest to extract resources, creating roads for forestry and seismic lines searching for underground oil and gas deposits.
Now picture yourself faced with the task of moving across this landscape: Will you push your way through dense trees and underbrush, or will you choose to walk on the trails?
Like humans, wolves often choose the path of least resistance, moving faster and farther on human-created trails through the forest. Increased wolf movement is believed to play an important role in the decline of the threatened boreal woodland caribou—an iconic species in Canada (just look at the quarter in your pocket).
We tracked 142 wolves using GPS collars across British Columbia, Alberta and Saskatchewan—spanning over 500,000 square kilometres. The tracked wolves spanned areas with low to high prey density (measured using a metric of habitat productivity, or how much vegetation there is for species like moose), and had varying access to human-created trails.
Wolves living in areas with high densities of human-created trails took up an area roughly 20 times smaller than wolves without trails, but only when they lived in areas with low habitat productivity. Comparatively, trails didn’t change the area needed for wolves when they lived in areas with high habitat productivity.
Think about picking berries. If the berries are hard to find, you have to go looking far and wide to get enough to fill up your basket. But if something makes it easier for you to find the berries, then you don’t have to look around as much. You can just grab all the ones that you see close to you. The advantage of being able to easily find berries would be less important if there are a lot because you can skip over a few without noticing. But it becomes more important when there are few to begin with, and every last berry counts.
This is exactly what we are seeing with wolves: Instead of choosing to travel far and wide, wolves with access to lots of trails stay close to home and get by with what they have.
The space animals use to carry out their lives is called a home range, or if defended from conspecifics like in the case of wolves, a territory. If animals have smaller home ranges, that means more animals can crowd into a given space, increasing the density of that species. It is well documented that animals need less space when there is an abundance of food around—and now we know that easier access to that food can also decrease home range size. We found that increasing a wolf’s access to their prey, through things like cleared trails through the forest, can decrease their home range size, likely increasing the regional density of wolves.
Habitat restoration
But why do we care about how big wolf home ranges are? One of the biggest conservation challenges in Canada is that of woodland caribou. Caribou live across large areas, overlapping places where the energy and forestry sectors are actively extracting natural resources like oil, gas and timber.
A remote camera capture of caribou in the boreal forest. Changes in wolf-hunting patterns are threatening the already endangered caribou. (Melanie Dickie/Caribou Monitoring Unit), Author provided
Habitat restoration is imminently needed, but is expensive and time consuming. Prioritizing habitat restoration in areas where it will be most beneficial to caribou as soon as possible is necessary for effective caribou management.
Habitat restoration has two main goals: to reduce wolf hunting efficiency by limiting their use of trails and slow their movement when on them and to return the forest to caribou habitat. But now we have reason to believe that slowing wolves down can also reduce wolf density on the landscape — forcing individual wolves to take up more space and push others out—especially in low-productivity peatlands, where the effect on home ranges is stronger.
Effective habitat restoration is going to be important for moving away from other management actions like wolf management in the long term. But, we have a lot of work ahead of us. There are hundreds of thousands of kilometres of these cleared trails that need to be restored. Our study points us towards prioritizing low-productivity areas to see the biggest effects sooner.
Every year as the temperature drops, hibernating animals, fattened from a summer spent gorging on food, prepare to hunker down for the winter. When they wake up in the spring, they’re healthy and strong despite months of inactivity. So how do they do it?
This was the question that Matthew Regan, an assistant professor of biology at the University of Montreal, and his colleagues set out to answer in a new study recently published in Science. Hibernation has long intrigued scientists, he explains. There was speculation that something in the gut helped some hibernators preserve muscle. Regan and his colleagues tested this hypothesis on 13-lined ground squirrels in Wisconsin and found that bacteria play a key role in helping them stay strong while they hibernate.
These ground squirrels are an “extreme example of hibernation,” Regan says. They are inactive for six months, during which time their metabolism is reduced by 99 per cent. When they wake up in mid-April, the squirrels “start eating furiously” and double their weight by the fall, he says.
Like humans, ground squirrels have many different kinds of bacteria in their gut, and one group of microbes is doing them an important service. While the squirrels hibernate, urea, the main component in urine, is transported to their intestines where microbes break it down, releasing nitrogen, Regan explains. Nitrogen is essential for making protein, and this process allows the squirrels to preserve and build muscle through the winter.
There is already interest in how this process could help humans prevent muscle-wasting—whether they’re patients on bed rest or astronauts in zero-gravity environments. Regan has received funding from the Canadian Space Agency to study the possible applications for space travel. However, the human gut microbiome is complex and delicate, and disruptions could have negative impacts, he says. So, careful research must be done before applying this mechanism in space.
For now, this process is best left to the squirrels. While it may be tempting to leave food out to help the little hibernators fatten up, Regan says it’s safer to “let them do what they’re evolved to do.”
The muskox is one modern-day mammal that looks a little like it just stepped out of a prehistoric museum diorama. Its shaggy fur could rival a woolly mammoth’s! This is of course because muskoxen live most of their lives in Ice Age-like conditions on the Arctic tundra. So, -40°C temperatures, wind, and blowing snow? Not a problem.
Clothing made from muskox wool is really, really warm
A muskox’s coat is made up of two layers: a woolly layer, close to the skin, and an outer hairy layer. Muskoxen wool is eight times warmer than sheep’s wool but finer than cashmere. The outer layer of hair, meanwhile, is longer than any other North American mammal’s. It’s coarse, and protects the insulating wool layer. A muskox doesn’t keep all this fur year-round; in midsummer, it sheds the insulating undercoat.
A muskox is not an ox
Despite the name, these mammals are not oxen. And even though they look like a hairier version of a bison—humped shoulders, short legs—they’re actually most closely related to goats and sheep. Both male and female muskoxen grow horns. Their horns are very similar; a bull’s are thick, and almost fuse together in a solid mass on the forehead. Females have a patch of fur that separates each (skinnier) horn. But either way, the horns are razor sharp. Muskoxen use them in defence, and, along with their giant heads, to smash through crusty snow cover. Snowplow? What’s a snowplow?
What do they eat?
During winter, muskoxen roam about in mixed herds. In the high Arctic, temperatures stay below -18°C for about eight months of the year, and it’s mostly dark between November and February. But muskox don’t care! The only conditions these beasts consider disruptive are massive blizzards. In this situation, a muskox will lie down with its back to the wind, and wait it out. Muskoxen head into winter with generous fat stores to help sustain them through the cold. Beyond that, they’ll target low-lying valleys—the snow is usually less deep there—and dig down to get at willows, sedges, and grasses. They have an excellent sense of smell, powerful enough to sniff out the buried vegetation.
What’s their population in Canada?
We have about 85,000 muskoxen. Not bad, given that they were once nearly extinct. They’ve been under government protection since 1917. (Even though they only have one predator—the wolf—human hunting didn’t do the population any favours.) And they’re certainly worth preserving: they’ve been around for a long time. Experts believe the muskox crossed over via the Bering Strait about 90,000 years ago.
The muskox is one modern-day mammal that looks a little like it just stepped out of a prehistoric museum diorama. Its shaggy fur could rival a woolly mammoth’s! This is of course because muskoxen live most of their lives in Ice Age-like conditions on the Arctic tundra. So, -40°C temperatures, wind, and blowing snow? Not a problem.
Clothing made from muskox wool is really, really warm
A muskox’s coat is made up of two layers: a woolly layer, close to the skin, and an outer hairy layer. Muskoxen wool is eight times warmer than sheep’s wool but finer than cashmere. The outer layer of hair, meanwhile, is longer than any other North American mammal’s. It’s coarse, and protects the insulating wool layer. A muskox doesn’t keep all this fur year-round; in midsummer, it sheds the insulating undercoat.
A muskox is not an ox
Despite the name, these mammals are not oxen. And even though they look like a hairier version of a bison—humped shoulders, short legs—they’re actually most closely related to goats and sheep. Both male and female muskoxen grow horns. Their horns are very similar; a bull’s are thick, and almost fuse together in a solid mass on the forehead. Females have a patch of fur that separates each (skinnier) horn. But either way, the horns are razor sharp. Muskoxen use them in defence, and, along with their giant heads, to smash through crusty snow cover. Snowplow? What’s a snowplow?
What do they eat?
During winter, muskoxen roam about in mixed herds. In the high Arctic, temperatures stay below -18°C for about eight months of the year, and it’s mostly dark between November and February. But muskox don’t care! The only conditions these beasts consider disruptive are massive blizzards. In this situation, a muskox will lie down with its back to the wind, and wait it out. Muskoxen head into winter with generous fat stores to help sustain them through the cold. Beyond that, they’ll target low-lying valleys—the snow is usually less deep there—and dig down to get at willows, sedges, and grasses. They have an excellent sense of smell, powerful enough to sniff out the buried vegetation.
What’s their population in Canada?
We have about 85,000 muskoxen. Not bad, given that they were once nearly extinct. They’ve been under government protection since 1917. (Even though they only have one predator—the wolf—human hunting didn’t do the population any favours.) And they’re certainly worth preserving: they’ve been around for a long time. Experts believe the muskox crossed over via the Bering Strait about 90,000 years ago.
The crossbill is a shining example of a bird with a bill that’s especially adapted to how the species lives and feeds. The tips of a crossbill’s beak literally cross, in a bizarre and dramatic overbite. Quick, get this bird some braces! No: the misalignment allows these avians to expertly snip cones from trees and, holding them in one claw, lever the scales open to expose the seeds. They then use their tongues to pull out the seeds.
What’s up with the bills?
Although plenty of birds have evolved bills to help them feed—the brown creeper, with its tweezers; the hummingbird, with its nectar-sucking syringe—a crossbill’s mouthpiece is particularly useful. A lot of bird food sources run low in the winter, but not for Mr. Crisscross. Conifer trees have plenty of cones all season long—no matter how frigid or snowy the weather. And since most birds don’t have the beaks (or the skills) to feed off cones…well, all the more for the red crossbill!
What do they look like?
Only the male red crossbill is actually red; females are yellow. They tend to forage in flocks, moving from one tree to another in a flurry of colour and noise. Crossbills can be as small as black-capped chickadees or as large as brown-headed cowbirds. There’s so much variation because North America has roughly ten different “types” of the species. (Experts, for the most part, don’t consider them subspecies.) Their beaks all vary slightly depending on the specific cones that they eat. Eastern Canada’s most common crossbill, for example, prefers pine and white spruce.
Why are crossbills noisy?
A red crossbill pair breeds in late summer, but, if the cone supply is plentiful, Mom and Dad will produce another two broods—even nesting and incubating eggs in the winter. Red crossbills will happily nest close to one another in areas thick with cones. As a species, they’re very social and generally good at sharing; ornithologists suspect that they call to one another while foraging to convey info about the quality of cones and seeds that they’re finding. This allows the flock to forage more efficiently—and that’s good for the species in general.
