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Archive for the ‘wild dogs’ Category

The Nest Raid

gray fox family

The snow fell in April, swirling in the soft spring breezes before coating the greening grass. Winter was breaking. Though the air was chill, the sun’s soft angles spoke of what was to come.

An Angus cow licked her newborn in the hill pasture. Robins sang in the black cherries. Trout anglers moseyed along country lanes to their favorite holes.

No one seemed to be thinking of the great chills of January and the tropical swelter of July.  The banal, sweet time was coming. The dogwoods would be in bloom. The Forsythias were already casting their diminutive yellow plumes, and a few redbuds were showing theirs.

And the meadow fox nursed her new litter. They were whelped a den dug at the base of a fallen oak. Four little gray foxes whined and whimpered over her swollen mammaries. Three were little vixens, and one was stout little dog fox that strongly resembled her father, who had been removed with a night hunter’s bullet on a distant November night.

Her new mate was a young fox, but over the late winter, he had become a maestro at running the country lanes for wily old cottontails. He had knew how to punch hard into the coverts of greenbrier and multiflora rose and force the hard holding rabbit into the open for a winter coursing.

But now that he had a mate and kits to feed, he was forced to try other avenues. He was hunting for five now, and he begun testing out his techniques as an arboreal hunter.

He had learned to climb up high in then canopy and raid fox and gray squirrel dreys.  In late winter, the squirrels would have their young in those dreys, and they were quite tasty and nutritious for a fox family.

He also raided every songbird nest he could find.  But only now,  as the sun began to work its way back to shining high at this latitude that the birds were laying enough eggs to be worth the trouble.

But as his young grew, he needed more eggs and more meat. When they were three weeks and sucking their mother really hard, he began his nightly egg hunt. It was a warm day in late April, and some of the hen turkeys had taken to brooding their nests in the undergrowth.

One old hen laid her speckled eggs along a cottontail lane. She didn’t seem to care that these lanes sometimes filled with predators. She’d fought off her fair share of raccoons, skunks, and opossums.  She knew that they really didn’t want to deal with a mad dinosaur mama with sharp claws and a piercing beak.

Even a fell boar raccoon would back down from her defense, and she knew that she had this power. So she sat smugly upon her eggs, almost daring some beast of the field to molest her brood.

On this warm day in April, the meadow fox’s mate went on an daylight raid. His mate needed food, and his babes needed milk.  He thought of darting along a well-known stand of autumn olive, where the towhees nest, but as he slunk along the trail, his nose caught wind of many eggs, big eggs, and they were lying out on the ground!

He changed his approach and began a jovial saunter towards the egg scent. He smelled a turkey, but his youthful inexperience led him to assume that these were stochastic variables.  He just knew there eggs and they were on the ground and they were going to be good food.

He came within ten feet of the nesting turkey hen.  She clucked a warning from her nest.  The fox thought it odd for a turkey to be clucking from such a thick covert. He cocked his head at the sound, turning his prick ears to catch the source of the sound.

He stood there for 90 seconds or so. Then he began his jovial jaunt towards the egg scent.  He made no more than four or five steps forward before the covert exploded with angry feathers.

The great turkey hen was upon the fox.  Her thick claws tore at his side and her sharp beak hammered him hard.

So surprised was the fox by this development, that he screeched and then ran.  The dinosaur mama held tight on his tail as he raced down the cottontail raid.

Then she turned and strutted back with the cautious calm of an Old West gunslinger. One could almost see her blowing the smoke off her pistol as she strolled out of town.

So that nest raid failed, but all was not doomed for the fox family. That night, many young, quite naive cottontails filled the lanes. The dog fox could catch several of them through the night. This supply of naive young rabbits would go on through the summer. No more would he have to climb trees and raid birds nests for survival. His family’s hunger would be sated on the tenderest of rabbit meat.

And so the young foxes grew up in the soft days of spring. They were weaned on regurgitated rabbit, and they played like kitten-dogs in the sun shine.

These were the rosy days of childhood. All made possible by a enterprising father, who wasn’t afraid to try raiding new sources of prey.

Read more about the saga of these gray foxes’

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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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african wild dog dentition

These are the teeth of an African wild dog or painted wolf that has been tranquilized.

One thing you might notice is all the extra cutting edges around the carnassial teeth.  These extra blades make it easier for them to bite into the meat of their kills and bolt down the food quickly before lions and hyenas show up to rob them.

Dholes, the closest living relative of the African wild dog, also have similar carnassials, as does the bush dog. This feature evolved in parallel in bush dogs,  but for a while, they were often classified with the dhole and African wild dog.

We now know that the bush dog is within the “South American clade” of wild dogs. Its closest relative is the maned wolf.

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painted wolves

I’ve been watching Dynasties on BBC America, and I have been waiting until the series got to the African wild dog episode. African wild dogs, which the series calls “painted wolves” in light of a direct translation of their scientific name,  Lycaon pictus,  are critically endangered canids.  Only 6,600 of them exist in the wild, and the series hooked up with Painted Dog Conservation to follow the high drama of two packs living at the Mana Pools National Park in Zimbabwe.

The story starts with a pack led by Tait. Tait is a ten-year-old breeding female, and she has over 200 descendants. One of these is Blacktip, the breeding female of growing pack, that now needs more territory to feed itself. Tait’s pack is in a pretty bad state.  Their numbers are small, and because the African wild dog range in the park is surrounded on two sides by lion and spotted hyenas, Blacktip’s pack drives Tait’s pack from its territory.

Tait’s family escapes to lion country, where they are forced to hunt impalas, choke down some bits of meat, and then run like hell when the lions eventually show up.  Blacktip’s pack lives very nicely, but they are forced to remain stationary while Blacktip nurses her pups.  When they get old enough to move, Blacktip leads her pack against her mother in lion country,  a campaign that will prove disastrous.

Spotted hyenas kill at least one pup, and lions almost off the rest of the litter. However, they are saved when a foolish African buffalo comes charging onto the scene.  The buffalo was unexpected,  but the lions hate buffalo more than they hate African wild dogs– and certainly prefer their meat.  So the lions kill the buffalo, and the pups are spared.

The campaign ends when a Nile crocodile catches one of Blacktip’s pups and drags it into the Zambezi. It is the most graphic scene in the whole episode. I could not help but feel for the poor wild dog as it died in the crocodile’s jaws. This is a horrible way to die.

After that campaign, Blacktip retreats to her old territory, and Tait’s pack is able to return to its old haunts. Just before we hear that they have returned, Sir David Attenborough narrates that Tait died at the hands of lions. She was too old to keep running.  Her mate refused to leave her side, and he dies at the hands of the lions. Surely, this scene had to have been witnessed, but it was probably too horrific to be shown as part of this documentary.

The film ends with Tait’s family hooking with some errant males. Their booming cries are hauntingly beautiful as the new males join up.  A new mated pair is being crowned, and Tait’s daughter Tammy becomes the new lead female. And Tait’s dynasty continues on.

This film shows many amazing hunting scenes. I’ve never before seen any footage of African wild dogs hunting baboons, a pretty dangerous undertaking.  Baboons are smart and strong and have massive canine teeth. But the dogs are able to cause such chaos in a baboon troop that some young ones do get left unattended in the melee.

In another hunt, Tait’s pack runs an impala into the Zambezi, where the crocodiles instantly devour it.  You almost feel the dogs’ pain as that impala leaps into the water. That good meat, now lost to the archosaurs.

In another scene, we see Tait’s tiny litter of only two pups that are almost instantly threatened by honey badgers.  One of Tait’s daughters flies into action and begins harrying the ratels to drive them off.

This film was such wonderful high drama. It was like the story of Exodus from the Old Testament, complete with its own Moses figure who never makes to the Promised Land, that mixes in with the story of Ernest Thompson’s Seton’s story about Old Lobo, the marauding wolf of the New Mexico ranges that dies because he will not abandon his mate.

And this story is fully true and documented before the rolling cameras.

Every time I watched those dogs run on their hunts, I thought how much they reminded me of sighthounds.  Their svelte frames seemed to glide across the plains, running hard and fast after the game. Dan Belkin famously compared the saluki’s running style to this species, and in watching their endurance runs, I have to agree.

I particularly have enjoyed the way this series has made a conservation message part of the documentaries. In this one, the final part has Sir David Attenborough and the wild dog trackers standing and sitting among the packs. They tell us of the real problems facing these dogs. They need big territories to hunt their game, but most of the painted wolves don’t live in national parks. Livestock ranchers and pastoralists shoot and poison the dogs, even if they have legal protections. Zimbabwe has set up corridors for wildlife that allow travel between parks, but most African countries that have these dogs have not. So they must constantly run a gauntlet of often hostile humanity as they try to survive at the edge of lion and hyena territories.

The painted wolf, the painted dog, the African wild dog, or the Cape hunting dog are all names that we use for this animal. I prefer “painted wolf,” but I realize that no one knows what I’m talking about when I use that term. I hope that this film popularizes that name a bit more. The name “African wild dog” connotes something feral, something that we can just kill off and not consider more deeply.

Lycaon pictus, the painted wolf, has a far more noble connotation. No, they aren’t as magnificent as lions, but in their intense social behavior, we surely must see ourselves. Like us, they evolved in Africa as a distant running predators, and we probably were intense competitors for he same sorts of antelope.  Our kind wound up taking over the whole world. Theirs remained in Africa, and now our kind has come quite close to wiping them off the face of the earth.

Films like this episode of Dynasties fully reveal the plight of these amazing creatures. They are pack-hunting wolves evolved in parallel on the great continent of Africa, and we are only now realizing their marvelous ways.

 

 

 

 

 

 

 

 

 

 

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smithsonian wolf

The Smithsonian Magazine has an interesting article with the very simple title “Should the Himalayan Wolf  Be Classified as a New Species?”

The article details the work of scientists who have gone around Nepal collecting DNA samples from wolf scat.  This is a difficult project, for wolves in this region have experienced quite a bit of persecution from man. Further, where they live is quite inaccessible.

The researchers have found that these wolves have some uniqueness in their mitochondrial DNA, and they have also found that they share some genetic markers with the African golden wolf.

This is all interesting stuff, but I would caution going out on a limb and creating a new species called Canis himalayensis.

The big reason is the studies that have  attempted to figure out where these wolves fit have base part of their calculations on an assumption that gray wolves and coyotes last shared a common ancestor about a million years ago. We know that from full genome comparisons that this assumption is faulty, and the most divergence between gray wolves and coyotes happened about 50,000 years ago.  The DNA studies have shown that the Himalayan wolf is closer to Holarctic wolf, as is the African golden wolf, which means that Himalayan wolves aren’t as divergent from Holarctic gray wolves as coyotes are.

I have argued many times on this blog that the best way to think of coyotes in light of the evidence of this recent divergence between gray wolves is to think of coyotes as a form of gray wolf, and I think the name for coyotes should be Canis lupus latrans.  It makes at least as much sense as Canis lupus familiaris for pugs and Yorkshire terriers.

Because of the coyote’s position in light of full-genome comparisons, I think that we really shouldn’t think of the Himalayan wolf as a distinct species. I have no problem with Canis lupus himalayensis.

I am quite open to the African golden wolf being recognized as a subspecies of Canis lupus. In light of the work performed on Himalayan wolves and the recent discovery that African golden wolves are almost entirely gray wolf in ancestry, I think this might be correct.

And if you use this species model for gray wolves, you wind up with amazingly phenotypically and behaviorally diverse species, which is reflected in both wild and domestic forms.

I find this a lot easier to deal with than this model that has all these different species described that wind up exchanging genes all the time, and then, because we have declared one form endangered, we get into culling all the hybrids.

We need full genome comparisons between African golden wolves, coyotes, Holarctic gray wolves, and Himalayan wolves to suss out fully what these exact relationships are, but it seems that all of these animals are much more closely related to each other than we initially assumed. We also need more comparisons of ancient wolf DNA, including DNA from the remains of the ancestral Mosbach wolves (Canis mosbachensis).

So there might be a new species of wolf in the Himalayas, but I don’t think the evidence is all there yet. And there are lots of reasons to be skeptical.

But I do think that a unique high altitude subspecies of wolf does exist in the Himalayas. It is very likely that African golden wolves and Himalayan wolves are genetic relics of what was once a more genetically diverse Canis lupus. These lineages have since been lost in the main Holarctic wolf populations, just as we have lost the lineage that led directly to the domestic dog in these wolf populations.

After going through the red and Eastern wolf taxonomic mess, we should be careful in assigning new species status for unique wolf populations, particularly when we are using only very limited DNA assays.

 

 

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Just a fox on a leash

Clive out for a snowy stroll.

clive on a leash

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snuggly clive

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