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Posts Tagged ‘wolves’

isle royale wolf

This year, several wolves were relocated from Minnesota and Ontario’s Michipicoten Island to Isle Royale.  These wolves were brought to the island to restore a moribund wolf population that had dwindled down to two individuals in the autumn 2018. These wolves had been suffering from a severe inbreeding depression, and because ice bridges almost never form in Lake Superior to connect the island to mainland Minnesota, it has become virtually impossible for wolves to walk to the island and add new genes to the population.

Climate change is, of course, to blame for this problem, but it also means that the island’s wolf and moose population dynamics that have been studied for decades are now going to be managed through occasional introductions of wolves that are not related to those living on the island.

Over the next few years, as many as 30 wolves will be released upon the island. This will create diverse founding population from which several packs can form.

But it now means that the biology of Isle Royale’s wolves will be managed by people.  People will be bringing new wolves to the island, not the ice bridges.

And we will be doing it for the rest of time.

This situation leads to certain questions about Isle Royale as a truly natural system. It is not. It is sort of a wildlife reservation in which two relatively rare species in the Upper Midwest are given a sort of illusory freedom to live in a way in which humans will mostly leave them alone.

But it’s not at all a Pre-Columbian ecosystem. Indeed, the main species that inhabited Isle Royale were Canada lynx and woodland caribou, both of which aren’t found there at all.  A population of coyotes also lived there, but the wolves made short work of them when they came over in the middle part of the twentieth century.

I do support the restoration of wolves to Isle Royale, but it is like everything else to do with wolves in this era. Some wolves in Alaska, far northern Canada, and Russia might still have lives that are true wilderness areas. Many of those wolves may never see a person in their entire lives.

But the wolves that live Western and Eastern Europe and Southern Canada and the Lower 48 live is worlds that are still dominated in by humans. Even if humans do leave behind some wild areas, the human footprint upon their lives is not inconsequential.

Humans have changed the climate, which has made ice bridges far less common in the Great Lakes.

Humans have also destroyed woodland caribou populations. Only a single herd of woodland caribou can be found in the Lower 48, and it dwindled down to a single individual, which was captured this winter.

Humans have pushed the Canada lynx into a range that essentially is just Canada and the Northern Rocky Mountain states.

Humans have made it so that wolves do very well in three Great Lakes states, but they don’t really exist anywhere else in the Midwest. They are absent from New England and Appalachians.

But they have Isle Royale and lots of moose to hunt.

We will give them that. It is the least we can do. And we will continue to learn from them in the deepest hopes that we can save some of them and the habitat they need to thrive. And if we can save a bit for them, maybe we can save ourselves, as the planet warms and politicians either do little to nothing or deny the looming threat as a hoax from some malevolent body.

So we will manage the wolf population now. This management will come from addition, while in the Rocky Mountains and the Pacific Northwest, the management will come from subtraction. In a few years, the rest of the wolves in Michigan, Minnesota, and Wisconsin will be managed with the minus sign.

And it will have to do. Because that’s what our civilization will tolerate.

 

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mallards

Common mallard = gray wolf

Domestic mallard (Pekin, Cayuga, Rouen, Khaki Campbell) = domestic dog

Black duck = Eastern wolf

Mottled duck  = red wolf

Mexican duck = coyote

Laysan duck = Ethiopian wolf

Hawaiian duck = African golden wolf

Gadwall= Golden jackal

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Diosbud pack

According the Seattle Times, a pack of wolves has been established west of the Cascade Range:

Western Washington has its first wolf pack in decades, an indication that wolf recovery is on track and a sign that the canines are expanding their range in a healthier ecosystem, wildlife officials say.

The Washington Department of Fish and Wildlife (WDFW) announced Thursday that biologists had documented a pack of the animals living in Skagit County, west of the Cascade crest.

A male wolf, which had been captured in the county and given a radio collar in 2017, was joined this winter by a female wolf, according to according to wildlife officials.

Biologists named the pair the Diobsud Creek Pack. The two have been spending their time near Diobsud Creek, in an area south of Baker Lake and north of Highway 20 near the town of Marblemount.

These wolves are moving into what most Easterners think of as classic Washington State with big wet forests and rumors of sasquatch behind every bush.

The article points to a real political and cultural divide in Washington. The eastern part of the state is very much ranching country, and wolves filling in from Idaho and British Columbia are not celebrated where livelihoods are dependent upon cattle prices and elk outfitting fees. This is the “Red Washington.”

Now, the wolves are inching closer to the “Blue Washington,” where they will likely cause some conflicts, and there will be less romanticism about living wolves.

However, the wolves certainly do deserve to be there, and as they become established in the forests near the Pacific Coast, there will be growing pains.

But it is a chance to see what wolves will do in these ecosystems. As they move towards the coast, will they begin to take up a littoral lifestyle as those in coastal British Columbia have?

Wolf “self-reintroduction” is going to be an interesting story in next couple of decades. Politically, it is impossible for us to go all the way back to wolf eradication as a federal policy, but there are forces that would like to get as near to that policy as possible. However, no state wants to the wolf to go back on the Endangered Species List, simply because the state loses virtually all control over the species once that happens.

So humans and wolves are still working it out, and the wolves keep spreading back into their former range.

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jan fyt wolf

The Revierjäger’s daughter wore a red hood when she went flower-picking in the forest. It kept the sun and rain off her freckled face.

And every day, she’d ask her father if she could walk to see Oma.

But Revierjäger knew there was danger about the forest. Two years ago, there had been a big peasant rising in the land, and when the king’s men crushed the rebellion, renegades hid out in the forest. They poached the deer and wild boar. Even after the rebels were starved out of their sylvan retreats, the game remained scarce.

The wolves of the forest found themselves without much to eat, so they slipped among the villages, lifting suckling pigs from the sows and running amok among the flocks.

The Revierjäger spent much of his time hunting down predatory wolves. He knew as well as anyone that wolves could hold back the recovery of the red stags that once roared in the rut in the green oak wood. But he also knew that wolves were a constant menace of the peasants, and their killings could spark another rising. Wolves take meat that could be sold or butchered, and bare peasant larders and coffers are the makings of revolution.

But what was worse was that a few wolves had taken to hunting people. No peasant legally owned a gun. Guns were instruments of the state only. Armed peasants could easily turn rebellious, and guns would be the perfect tools of poacher-fed revolt. They could off the margaves and the militiamen, then go deep in the beeches and drop a hind for a bit of supper.

So the wolves learned that peasants, especially young children and women, were easy prey. Every month or so, a story would spread through the villages about some child who disappeared while tending sheep or swine. Bandits or Roma were often branded as the culprits, but virtually every time, the child would disappear along a trail heavily marked by wolf tracks.

So the Revierjäger could not let his daughter go alone to see her Oma, but every sunny morning, the girl would ask her father. And every time, he turned her down. He could not risk his beautiful child’s life in a forest where wolves hunted people. Her mother had died at the hands of rebels, and their daughter was the only family he had left in this world.

Yet his guilt burned within him. Every other Sunday, he would take her to see Oma, and they would eat a fine feast of roast pork. They would visit a bit, but as the afternoon shadows grew longer, Revierjäger would summon the muster to tell the little girl that it was time to go, and they would cut back through the forest to his home cottage. Most times, she would cry piteously about the decision to leave. Great gushing tears would rush down her cheeks, which would flush as red as her hood from her anguish.

Every other Sunday was a great joy followed by a great sorrow, but he knew he had to let his daughter see her mother’s mother. She was the last remnant of his late wife’s side of the family, and he knew he must keep the family ties connected, even if he had to see his little girl cry.

So after one Sunday afternoon visit came to an end, the Revierjäger realized that he could no longer refuse his daughter her requests. As they rode home through the green wood, he knew that if the little girl asked him in the morning, he would grant her that wish to go see Oma.

He knew that there was risk involved, but he could no longer stand to see the little girl cry so much. He had to put her at risk just so that she could be happy.

Plus, no one had seen even a wolf track along that forest road to Oma’s house. It wasn’t that much of a risk, the Revierjäger reasoned to himself.

And so he made his decision. He slept little that night, but when his daughter asked that glorious Monday morning, he gave the answer that he knew he had to give. But he had some regulations:

2″You shall stay on the forest road. You must not wander from it. You will walk to Oma’s house and nowhere else. You will not speak to /strangers. And above all, if a wolf shows up, make yourself look big and tall. Lift up your red hood to make you look like a giant and shout at it. Do not run. The wolf will be on you in seconds if you do.”

The little girl stared up with her father. He expected fear to rise across her face, but instead, he saw hard resolve.

“Yes, father, I will stay on the road. I will not speak to strangers. I will go right to Oma’s house, and I will make myself look big if I see a wolf. I will be safe.”

“You must wear your hood. I feel a hint of rain in the air.”

He handed her a basket full of bread to carry on her way.

“If you get hungry, eat some this bread, but keep most of it for Oma. She will be thrilled to see you arrive with such a nice bit of food.”

In the basket, the Revierjäger placed a note to Oma. It was a note expressing his permission for the little girl to make such a journey and instructions on what to do with that bread in the basket.

And so the little girl headed down that forest road on the way Oma’s house. The Revierjäger fretted the whole time, and he was sorely tempted to follow the girl down the road. But something made him stand still, something that he could not explain.

But when he made the decision to follow her, a local blacksmith came rushing up to the cottage. The blacksmith said he’d found a poacher’s camp in the far end of the forest. and any Revierjäger worth his salt knew he had to check it out. And so the Revierjäger rode off in the opposite direction to inspect the poacher’s camp.

The daughter made her way down the road until she got to the point where the trees grow thick along both sides of the road. They shaded this whole bit of land, making the whole scene dark as if it were dusk even in the sunny days of July.

A raven croaked in the canopy of the trees. The wind was still, but the air was dank even for summer.

The little girl drew her hood in more tightly to keep out the chill, and as she proceeded down the road, the sounds of the forest seemed to dissipate. It was an eerie silence that now befell the forest road

She walked on and on. Her face showing strong resolve as she marched along the forest road.

But at that point, the leaves on the right side of the road began to rustle. She stopped and stared into the forest, but the growth was so thick she could see nothing. She told herself it was nothing and continued down the road.

At various points along the trail, shadows would move in the gloom, but she could not make out their shape. She told herself it was just her imagination.

She continued on and on until she came to where a massive boulder had rolled down to the edge of the road. As she came upon the boulder, a wolf leaped upon the boulder then bounded off it, landed in the middle of the forest road, and loped toward the girl. 

The wolf’s left ear was hanging down, an old injury from an errant boar tusk, and his face was all scarred from the fighting he did with his pack-mates over the last scraps of meat they could scavenge from forest.He.

He was a ghastly, demonic sort of wolf. And his amber eyes were fixed upon the girl. She was now his prey, and an easy kill at that.

But as the wolf approached with such menace in his eyes, the girl remembered her father’s words, and she lifted up the red hood off her shoulders. She made herself look tall and powerful, and she shouted at the wolf. She marched toward him with the swagger of a sailor, and the wolf was taken aback by such a display. He tucked his tail between his legs and scurried back into the thick brush.

The girl knew she had done something powerful. She had made the wolf back down. She now marched down the forest road, confident that she had stood up to such a terrible beast.

She continued down the path to Oma’s house, but what she could not know is that the night before, a pair of wolves slipped into Oma’s bedroom. They were skilled man-eaters, and they made short work of her corpse. 

The two wolves were resting in the front room of Oma’s cottage. They growled when they heard the approaching footsteps, but their bellies were too full of meat to get them that excited. 

When the girl walked up to the house, the wolves stood and stared at her. She was shocked to see them standing there. She noticed that their muzzles were covered in blood, and they stared at her so hard and intently, that fear took over and she ran. Her decision to run was not wise, for it stimulated the wolves’ predatory instinct. They chased after her, and after only short run, they were on her. They easily tore the girl apart, but because they weren’t particularly hungry, they just rolled around a bit and moved into the shade of an oak tree that lay just beyond Oma’s cottage. 

As the pair of wolves rested beneath the oak,  a man’s form appeared along the edge of the wood.  It was Revierjäger. He had tried to track down the poachers’ camp, but he then began to worry about the fate of his daughter, he decided to walk over to make sure everything was okay. 

He saw wolf tracks in the dirt in the road. So he loaded his musket.  His years of forest experience had honed his instincts. He seemed to know that fresh wolf tracks could mean something bad had happened. He was ready for the worst.

As he came upon Oma’s cottage, he saw the mutilated form of his daughter in the lawn.  Tears shot down his face. He dropped to his knees and wept, but as he wept he saw movement below the oak at the far edge of the lawn.  There were two wolves. 

Feeling horrific rage, the Revierjäger fired his gun. One wolf fell, but the other ran before he could load again. 

The wolf fell dead and hard on the ground.  The Revierjäger had the last of his family to bury.  

But in a few days, every villager within miles would be out with every barking dog, beating the forest for wolves.

Revierjägers from all around would fill the wood with firing guns. The wolves fell hard on the ground.  Wolves were trapped with iron footholds and with pit traps.  Dogs tore them apart.

And after four months of revenge, scarcely a wolf existed in that wood.  The peasants could graze their sheep and allow their swine pannage once again.

But the Revierjäger had a life to put together again. And everyone knew about the horrors of wolves in the deep forest. They would tell their children, who would tell their children, and so the fear was known long after the last wolf howl rose from the oak wood in that region.

Some of their descendants would come to North America, and they would kill every wolf and coyote they saw, simply because they knew what happened when wolves were allowed to live upon the land. They never saw a wolf attack anyone, but they knew that they would, simply because that is what they were told. 

 

 

 

 

 

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black coyote

For most of my life, scientists believed that the present era was still the Holocene.  Glaciers retreated with a global warming trend around 11, 650. Man went from being the apex predator over much of the world and became the apex consumer. Agriculture allowed our populations to expand, and we started to give up our wandering ways and became “civilized.”

It was generally believed that the past few centuries are but a continuation of this age, but now a growing number of scientists believe we have left the Holocene and entered into the Anthropocene. Several scholars have issues with this new distinction, but I think it is quite useful. In this era, human activity is the main factor affecting climate and ecology, which is why the age is named for the Greek word for human (anthropos).

The best argument I’ve seen for when this era began is 1610.  In this scenario, the era is dated to when European disease and conquest killed off enough Native Americans and enslaved and enough African had been enslaved to allow forests to grow back in former agrarian fields.  This process started in 1492, but by 1610, enough of those trees had grown to remove enough carbon dioxide from the atmosphere to push the planet into the Little Ice Age.

Darcy Morey and Rujana Jeger have a great model for understanding dog domestication as a change in trophic strategies.  In the Pleistocene ecosystems, most wolves were mesopredators, playing second fiddle to an ecosystem full of cave lions, machairodonts, large bears, and cave hyenas. When these wolves hooked up with people, though, they hitched their wagon to the species that often behaved as the apex predators in the ecosystems.  When humans switched to agrarian lifestyles during the Holocene, humans became apex consumers, and dogs joined us as beneficiaries of being allied to that apex consumer species.  During the Holocene, many wolves became apex predators, as the cave lions and other large predators became extinct.

I’ve always liked the framework that Morey and Jeger derived in this paper, but now that we’re entering into a new geological age, maybe we need to look at the change in trophic strategies of wolves in this new age.

Morey and Jeger don’t have a good framework for what happened to wolves in the Anthropocene, but across Eurasia and North America, wolves were gone from many human-dominated landscapes by the first decades of the twentieth century.  They existed only in isolated areas in Western Europe, and in the  lower 48 states of the US, they lived only in Minnesota and in an isolated region in East Texas and Louisiana, where the taxonomically controversially red wolves were located.

Large pack-hunting wolves were really in quite a bit of trouble.  In the United States, the coyote population began to expand out of its Western core range into the Great Lakes States. They eventually made to New England and the Maritimes of Canada, and they hybridized with relict wolves and the expanding population of domestic dogs.  Coyotes eventually colonized all the Eastern states, and as they did so, they largely became the apex predators in many parts of their range.

But in the 1960s, attitudes about wolves began to change. Many nations protected wolves, and there were often introduction plans in the works.  By the early decades of the twenty-first century, wolves were making significant comebacks in Germany and Italy. The wolves in Italy were often living very much like stray domestic dogs, living large at garbage dumps. Wolves live near large cities in Germany, and how these wolves are going to adapt to living in such human dominated environments is going to be a major question for researchers.

And in throughout Eurasia, we began to see that domestic dogs were mating with wolves.  Indeed, it is now estimated that a majority of wolves in Eurasia have relatively recent dog ancestry. 

Similarly, as coyotes expanded in North America, their genes began to work their way into the wolf population.  Yes, coyotes in a large part of the US have wolf ancestry, but we also have discovered that wolves across North America have coyote ancestry. Indeed, one interesting thing about these genome comparisons is that coyotes and wolves are much more closely related than we initially gleaned form mitochondrial DNA analysis. The calculation is that the gray wolf and the coyote last shared a common ancestor around 50,000 years ago.  This recent common ancestry has a taxonomic implication, which is that coyotes are themselves a divergent form of gray wolf in much the same way domestic dogs are.

In the Anthropocene, the wolves that have done the best have been the domestic dog and the coyote. The domestic dog’s ability to ingratiate itself into human society or live very nicely as an opportunistic scavenger/hunter on the periphery of humanity is a great gift.  The coyote can live as an opportunistic scavenger/hunter as well, and it also can live very nicely as a mousing fox or pack up and hunt deer.

Gene flow among wolves, coyotes, and dogs has made these entities much more fuzzy than we once thought they were. Dog genes are working their way into both the coyote and wolf population.  Strange pelt colors are popping up in the wild animals. The black coloration in domestic dogs was conferred onto the North American wolf population during the Holocene, but this same mutation for melanism has entered the coyote and Italian wolf population in very recent years. Dogs have introduced dewclaws on the hindlegs to some wolf populations, and I have seen photos of Eastern coyotes that have those hind dewclaws as well, which likely were introduced through breeding with domestic dogs.

Coyotes in the East are evolving larger size to become better predators of deer, but becoming larger and more effective ungulate hunters will have a trade-off. As carnivorous mammals grow larger, they become more and more dependent upon large prey to survive.  Very large wolf-like coyotes will lose their ability to live well on small prey and garbage.

So in the Anthropocene, dogs remain allied to the apex consumers. Some coyotes operate as apex predators, and some wolves live as opportunistic scavengers.

And as these creatures adjust their trophic strategies in a much more predator tolerant world, the pseudo species barriers that exist among wolves, coyotes, and dogs can break down. Hybridization among these creatures is likely to be a major feature of their continued evolution, a definite feature and not a bug.

These canids  thus make the leap with us into this human dominated age, an age that is experiencing a mass extinction of amphibians and great retrenchment of large sharks and big cats.

Yet they are still there. Evolving as the winds change. Winds that we ourselves are changing and are only now starting to understand.

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Charles Darwin was an early proponent of humans belonging to a single species. The concept was not popular in Darwin’s imperialist nation, where many of the best and brightest were dead certain that “lesser peoples” of the empire were entirely different species. Monogenists versus the polygenists this was the debate by even those who accepted Darwin’s controversial thesis that species evolved through natural selection and that humans evolved from African great apes.

We know now that the monogenists won out. Only the basest racist frauds believe that humans represent multiple species deriving from distinct evolutionary lineages. The only exceptions are that we do have evidence that humans have trace amounts of other extinct humans in their DNA, such as Neanderthals and the Denisovan hominin.

The monophyly of a species is a concept that should be axiomatic. Much of the “rewriting” of taxonomy and systematics comes from us discovering that a clade is either paraphyletic or polyphyletic, but what does sometimes happen is we do run into situations where we have thought species were really distinct but now we think of them as being subspecies. Black-tailed and mule deer come to mind, as do Cape and African forest buffalo. We have to combine them in a single species to retain its monophyly.

I think something now must be done with gray wolves and their closest kin. In recent years, it has become difficult to retain that domestic dogs and dingoes remain distinct species from the Holarctic gray wolf, especially if we wish to keep the species monophyletic. But I think now a good case can be made that coyotes belong to the same species as Canis lupus. They diverged from a common ancestor only recently, around 50,000 years ago, and the much debated Eastern and red wolf “species,” which appear to be hybrids between coyotes and gray wolves can also similarly be folded into Canis lupus. Whether there was a coyote sister population in the Eastern forest that gave rise to red and Eastern wolves is a moot point. That “forest coyote” population is no more distinct from gray wolves than those of the West are.

Further, we do have evidence of continued gene flow between gray wolves and coyotes. Eastern coyotes have wolf ancestry, and many also have wolf ancestry that comes from domestic dogs.

This new way of describing Canis lupus forms has some benefits. One is that we can come up with a strong legal foundation for the protection of red and Eastern wolves without them being distinct species. Their hybrid status is no longer problematic. We no longer must strain credibility talking about them being ancient North American wolves. Instead, we just go the Endangered Species Act’s statute language which defines an “endangered species” as being a “subspecies” that requires conservation action. We currently protect the Florida panther as an endangered species using this definition, and what is more, the Florida panther was given genetic rescue when Texas cougars were released into its range. The Florida panther exists as a hybrid that holds onto alleles of a population that no longer exists in its pure form, and in the case of red and Eastern wolves, one can very easily make this case.

The problem with going this route is that coyotes themselves do not experience many protections in the United States or Canada. Most states have a very open hunting season on them year-round, and some places have bounties on them. Eastern coyotes are hard to tell apart from what are called Eastern wolves and are even harder to tell apart from red wolves. There is an overlap in phenotype that comes from both forms having similar hybrid origins.

Further, because red wolves living in the North Carolina recovery range are all derived from 19 individuals, and wild wolf-like canids have inbreeding avoidance behavior, it is quite common for red wolves to pair up with Eastern coyotes. Much energy has been devoted to killing off and removing coyotes in red wolf recovery zones, including the euthanasia of crossbred puppies, but it seems that this won’t work long-term.

Recently, researchers at Princeton discovered that the coyotes of Galveston Island are quite closely related to the red wolves in the recovery program. The authors think that many southeastern coyotes might hold the alleles of these red wolves, but I think a better explanation is that we simply under-estimated what the coyote’s range was in the United States at the time of contact. John Smith described the “wolues” of Jamestown as not being much larger than English foxes, and I initially thought he was talking about gray foxes. But then I read original text, and the gray fox is described in complete detail, including the fact that it lacks the red fox’s odor. Henry Wharton Shoemaker, the naturalist and folklorist who chronicled much of the lore of Pennsylvania’s wildlife, wrote about a “small brown wolf” that lived along the Susquehanna River, which made a yipping howl that resembled that of the prairie wolf or coyote. Shoemaker postulated that these small brown wolves were the same species as the coyote, but very few scholars have taken his speculations seriously.

Perhaps, there were coyotes living in the forest alongside Eastern wolves and a endemic Southeastern form of wolf that was very often melanistic. All three exchanged genes, and all three were killed off for their furs and for bounties without any regard to what they were. It was only when settlers in Indiana noticed that some of the wolves in their area were quite small that they began to wonder if they were a distinct species. Later explorers into the West began to call them prairie wolves, which was their name until Americans adopted the Nahuatl-derived name for them.

The most important bit of text I’ve read in any of these North American wolf taxonomy papers is one in a response paper to another one that still argues for multiple species of wolf in North America. The authors write that “[the] genetic differentiation between red wolves and other North American [wolf-like] canids is comparable to the amount of genetic differentiation found between different continental human groups, which of course are not considered to be distinct evolutionary lineages.”

And at that moment, we are back to Mr. Darwin’s debate with the polygenists. He was right to oppose their claims back then, and maybe when it comes to North American and Eurasians wolves, dogs, dingoes, and coyotes, one should be a monogenists.

That’s where I am planting my flag. I think that is where it will all end up once we’ve sorted it all out.

I find the idea of gray wolves representing a phenotypically and behaviorally diverse species awfully intriguing. This diversity is greatly exaggerated in the domestic form, but this diversity is also reflected in the wild, where we have 15-pound coyotes and wolves that weigh 130 pounds.

It may even be that the African golden wolf, which is derived from the ancestor of the gray wolf and coyote mating with the ancestor of the Ethiopian wolf, may be close enough to extant gray wolves that we might also regard it as part of this very diverse species. It would be a coyote-evolved in parallel out of the gray wolf lineage, for the coyote likely evolved in its smaller and more generalist form from the ancestral Eurasian gray wolf because it could not compete as a pack hunter in a North America dominated by dire wolves. African wild dogs once ranged over almost the whole continent of Africa, and they could have provided competition for that niche that would force these ancestral gray wolves to evolve in something like an African coyote.

The recalibration of the evolution of Canis needs to be done with light of the knowledge that gray wolves and coyotes aren’t so genetically distinct from each other. We need new papers that look at he full genomes of golden and Himalayan wolves to get an idea of when they may have split from the rest of the gray wolf swarm. It may be very well be that they all belong to this wide-ranging phenotypically diverse species that over parts of four continents

Yes, this is controversial, but I think it is parsimonious. So many scientists now have no problem thinking that pugs and Yorkshire terriers are Canis lupus familiaris, so why is it so difficult to think of coyotes as being Canis lupus latrans?

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We don’t really think of antlers as being practical weapons. No species of deer that has them has them year round, and in only one species, caribou/reindeer, do both sexes have antlers.

We tend to think of antlers as being used to attract the opposite sex and for ritualized combat between conspecifics, usually just competing males during the rut in all species but caribou/reindeer. In that species, the females retain antlers well into the winter, which they use fight for preferential feeding areas, a great asset in feeding the calves they carry through the long northern winters.

But we don’t normally think of them as weapons to be used against predators. After all, predators are a problem that plagues deer all year, not just during the rut, and if they were widely used in fighting off predators, one would think they would evolve to hold onto them permanently or at least for longer periods of the year.

Well, a recent paper in the journal Nature examined how these factors work with regard to elk living in Yellowstone, where wolf predation is a significant factor in elk survival.

The authors found that bull elk that lose their antlers relatively early tend to be in better physical condition than those that retain them, and those that lose their antlers early tend to grow larger antlers than those that retain them, simply because they have more time to grow their new antlers in the coming year.

The authors found that there is a massive trade-off for how long elk hold onto their antlers. Those bull elk that lose their antlers are preferentially targeted by wolves. Yes, even though they are in better physical condition than those that retain them, the wolves go for elk that lack antlers as weapons.

Predation from wolves could be driving elk in Yellowstone to hold onto their antlers longer, and it could explain why elk in general hold onto their antlers long after their breeding season.

This study has some interesting implications, because wolves could indirectly be selecting for smaller antler size in elk, simply because the elk that lose their antlers sooner tend to have bigger racks in the following year. Further, because the elk hold onto their antlers longer when they are in poorer physical condition, the wolves could be selecting for weaker elk that are much poorer foragers than they might otherwise be.

These questions were not addressed in the paper, but I’m sure the questions did arise as the researchers looked at their data. More work is going to have to be done, but it is clear that wolf predation is a lot more complex in how it selects for fitness in the elk population than we might have assumed.

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