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Grey Wolf - Canis lupus
#46
Some instances of wolf predation I thought were either interesting or impressive :

The surviving wolves of Mollie’s Pack continued to go missing from the Pelican Valley until February of 2005, when we spotted them attacking and eventually killing a bull bison. Remarkably, the kill was made by wolf Number 378 and just one other adult, along with the questionable assistance of four eager, though mostly unskilled pups.

 ...
The Soda Butte Pack made a quick kill a mere half mile from their fenced enclosure, as Number 10, who just a few hundred yards from his pen managed to kill a bull elk weakened by winter and poor nutrition.
- Decade of the Wolf : Returning the wild to Yellowstone

 
One snowy February afternoon, a few lucky visitors watched as O-Six came thundering down off a ridgeline on the north side of the Lamar valley in hot pursuit of a bull elk, her two companions sprinting along behind her. The elk bounded across the road near Buffalo Ranch, heading for the Lamar Valley beyond. O-Six never slowed, but 754 and 755 pulled up when they reached the backtop, unwilling to cross. O-Six eventually took down the bull herself in the river valley below."
From 'The Wolf : A true story of survival and obsession in the west'. 

A few weeks earlier, 104 had single-handedly broken a mother buffalo’s defences and killed her calf. This morning, he was spotted chasing another buffalo calf and several wapiti.
Behaviour article ‘Out of the Woods’ in the September 1998 Issue of BBC Wildlife
 
The chase continued, a female faltered. The wolf was at her hind legs. She tripped and rolled but sprang up. The wolf lunged, this time catching her on the flank. Again she stumbled. This time, she did not rise. As the dust cleared, the wolf’s powerful jaws clamped like a vice grip on her throat. The other elk kept running, but suddenly stopped two hundred yards away. Within moments the wolf had subdued the unlucky cow.

The standoff lasted about twenty seconds. The male bolted forward. Within two minutes, another elk, again an adult female, stumbled. He killed her, also by the throat. This time he only fed for four minutes. I marveled at what I had just seen. A single Teton wolf killed two adult elk 18 minutes apart.

- Joel Berger, The Better to eat you with; fear in the animal world
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#47
The secret lives of fish-eating, beaver-ambushing wolves of Minnesota

In the Great Lakes' boreal forests, gray wolves have evolved surprisingly flexible diets and hunting strategies.

In a serene, spongy wetland in Voyageurs National Park, a remote quilt of forests and lakes that blankets northern Minnesota, Tom Gable is investigating a violent slaying.


The biologist crouches atop peat moss, pondering the evidence left by last night’s struggle. The clues are subtle but grisly: blood-stained leaves, tufts of hair, fragments of bone. A mulchy odor rises from a clump of half-digested plant matter—the victim’s last meal.

The casualty: a North American beaver.
The perpetrator: a 76-pound male gray wolf, perhaps five years old, known to Gable as V074.

“This wolf’s been on a beaver-killing rampage,” Gable says as he inspects a low branch snapped in the struggle. “He’s already killed at least four this spring.”


Gable, a Ph.D. student at the University of Minnesota, has been on V074’s trail for months. He’d captured the wolf last fall and outfitted him with a satellite collar, which alerts Gable every time the predator dawdles in one location for more than 20 minutes—likely an indication that the wolf has made a kill.

Comparing the beaver’s scattered remains with the GPS points transmitted by V074’s collar, Gable reconstructs the attack. The wolf, it appears, had hunkered down in the wetland and waited. As a beaver trundled past during its nightly dam maintenance, the wolf sprung, subdued his prey after a brief battle, and consumed the body in a spruce copse—bones, fur, and all. (Meet the rare swimming wolves that eat seafood.)

Picture Canis lupus on the hunt, and you likely imagine a pack racing across a Yellowstone valley on the heels of an elk, not an individual wolf skulking through a swamp to ambush a rodent. Over the last seven years, however, a research initiative called the Voyageurs Wolf Project has revealed that the region’s wolves have surprisingly eclectic tastes.

Gable and colleagues have detected wolves chowing down on swans, otters, fish—even blueberries. What’s more, rather than exclusively chasing their prey, wolves lean on a diverse repertoire of hunting strategies, some of which hint strongly at advanced cognition and even, perhaps, culture.

“We’ve seen that wolves are far more flexible than most people had realized,” Gable says. “That gives us a new understanding of how they’ve proliferated across the Northern Hemisphere.”

Lone wolves

Wolves are among our planet’s best-studied animals, yet in the boreal forest, the wooded belt that girdles North America and Europe, their habits have remained relatively mysterious—particularly in summer, when dense vegetation makes it difficult to radio-track wolves or observe them from the air.

Within the last decade, however, improving satellite collar technology has permitted researchers to keep tabs on wolves from space.

Since 2012, Voyageurs Wolf Project biologists have trapped and collared 74 wolves from a dozen packs, then investigated thousands of GPS points where their subjects linger. By collecting scat and scrutinizing kill sites like forensic detectives, scientists can tell what—and how—wolves are hunting.

In any given year, somewhere between 30 and 50 wolves inhabit the Voyageurs ecosystem. The animals are currently protected throughout the Midwest by the U.S. Endangered Species Act, although that could change under a new federal proposal. (Read more about wolves and their endangered status.)
“The Greater Voyageurs Ecosystem is one of the only places in the United States where wolves were never extirpated,” says Steve Windels, a biologist with the National Park Service, which oversees the project. “That makes it a perfect place to understand how all its components evolved with each other.”
As it turns out, Voyageurs’ wolves rely on a rotating buffet, switching between food sources with an almost ursine flexibility.
In winter, they congregate in packs and deploy coordinated hunting strategies to chase adult white-tailed deer. In spring, though, the pack disperses, its members largely going their separate ways to seek smaller prey.

“You have this animal that’s a famous social predator, but it’s also a solitary predator,” says Gable. “They spend half their lives by themselves.”


As wolves become more independent, their palates shift, too. In May, when juvenile beavers leave their lodges, wolves gobble up the vulnerable rodents. In June, wolves sniff out deer fawns in their grassy hideouts, seizing the newborns in powerful jaws.
Although July and August are plentiful times for most animals, they’re lean months for wolves: Beavers have settled down, and fawns have become too swift to kill. With prey scarce, wolves turn omnivorous.
In 2015, Gable tracked one pack to a ridgeline, where he found scats so packed with blueberries he initially thought they’d been deposited by a black bear. Instead, wolves, North America’s most iconic carnivores, had developed a taste for fruit. (Learn about “the most famous wolf in the world.”)
In the summers since, Gable has learned that some packs turn to berries for 80 percent of their late July diets. “They grab the whole stem and pull, leaves and all,” Gable says. “You’ll see these ridgelines that have just been stripped.”
Versatile diets
Later in the season, Voyageurs’ wolves exploit an even stranger cache of calories.
In Minnesota, hunters are permitted to “bait” black bears, enticing the bruins with nuts, seeds, and candy to make them easier targets. Beyond park boundaries, wolves gobble up the junk food: In a 2018 study, Gable found that bear bait supplied 12 percent of one pack’s early autumn food. Wolves also devour the discarded guts of hunted bears, and may even kill bears wounded by bullets.

Other forms of lupine resourcefulness are more natural.
In April 2017, Gable followed one yearling male to a stream, where he found the banks glittering with the scales and gill plates of mutilated northern pike. That spring, two wolves spent around half their time feasting on suckers migrating upstream to spawn—the first time scientists had observed wolves preying on freshwater fish.
The lesson: After decades of research, wolves still confound our expectations. (See unique pictures of wolves taken in Yellowstone.)
“As soon as you feel like you understand what’s going on, something new happens,” Gable says. “We become more aware of our ignorance as time goes on.”

Ambushed

To be sure, biologists have long known that wolves will eat just about anything they can catch—including beavers, which have rebounded spectacularly throughout North America after human fur traders pursued them to within a whisker of extinction. One study set in Alberta, for instance, found that beavers comprised nearly a third of wolves’ summer diets.
Despite their prodigious appetites, Voyageurs’ wolves don’t appear to dent the park’s immense beaver population. Elsewhere, the story may be different. Between 2010 and 2018, the number of beaver colonies on Michigan's Isle Royale National Park spiked five-fold, says Sarah Hoy, a wildlife ecologist at Michigan Technological University. That explosion roughly coincided with the decline of the park’s wolves.
According to Hoy, the Voyageurs research is exciting not merely for its documentation of wolf diets, but for the extraordinary window it’s opened onto how wolves kill their prey.
“In our system, we’ve known that wolves prey upon beavers, but we haven’t known whether they just do it opportunistically,” she says. “The Voyageurs work has very nicely documented the ambush approach.” (See 12 of our favorite wolf pictures.)
Since 2015, Voyageurs biologists have identified more than 400 wolf-on-beaver ambush sites—spots where the canids bedded down along the foraging trails that beavers carve between pond and forest. Wolves tend to spring their attacks from downwind, so beavers can’t sniff out the threat, and far from the water, to prevent their victims from making aquatic getaways.
Such premeditation, wrote Gable in one paper, suggests that wolves employ “higher-order mental abilities along with information learned from prior interactions.” In other words, they learn and plan.

Cultured predators?

To Joseph Bump, a University of Minnesota ecologist and Gable’s co-advisor, that hints at the potency of wolf cognition—and even, perhaps, something resembling culture, behavior shared by a group and transmitted through social learning.

Might wolves improve at ambushing prey over their lifetimes, their tactics honed by years of practice? Do older wolves teach younger ones, transmitting knowledge across generations? (Read how whales may have culture.)

“Wolves may develop expertise in ways we don’t yet understand,” Bump says. “Tracking dietary changes makes it possible to ask some really big questions about carnivore cultures.”
The likelihood that beaver-hunting is a learned skill, rather than an innate one, is corroborated by the fact that not all wolves are equally adroit ambushers. Some wolves nab only one beaver in a season. Others are prolific: One breeding male in Voyageurs dispatched a whopping 28 beavers in 2016 alone.

“I don’t think that’s solely due to opportunism—there are wolves that know how to hunt beavers, and those that don’t,” Gable says. “They’re able to piece it together to survive in a wild and harsh world.”

https://www.nationalgeographic.com/anima...onal-park/

Interesting popular article on wolf dietary flexibility and intelligence. Also note a healthy 5yo male being 76 lbs, which is actually the average for the Minnesota region too. This is believed to be due to ecological reasons but also past coyote hybridisation.
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#48
Gene transcripts from ancient wolf analyzed after 14,000 years in permafrost

by Public Library of Science

RNA—the short-lived transcripts of genes—from the "Tumat puppy", a wolf of the Pleistocene era has been isolated, and its sequence analyzed in a new study by Oliver Smith of the University of Copenhagen and colleagues publishing on July 30 in the open-access journal PLOS Biology. The results establish the possibility of examining a range of RNA transcripts from ancient organisms, a possibility previously thought to be extremely unlikely because of the short lifespan of RNA.

DNA, which encodes the "hard copy" of genes, is known to survive for thousands of years under favourable conditions. But RNA—the short-lived working copy of a gene, which is transcribed from DNA in the cell and forms the instructions for making proteins—is rapidly broken down in living tissue by a suite of recycling enzymes. That instability typically continues after death, and because of that, researchers have generally assumed that the likelihood of finding intact an ancient cell's complement of RNA—its transcriptome—was vanishingly small. But there have been a few exceptions, mostly in plants, which led the authors to ask whether there might be ancient animal transcriptomes well-preserved enough to be sequenced.

They isolated and analyzed RNA from liver tissue of a 14,300-year-old canid, possibly a wolf or partially domesticated wolf-like creature, that had been preserved in Siberian permafrost until its discovery, as well as tissue from two 19th- and 20th-century wolves for comparison. Using a variety of transcriptomic techniques and quality control measures, the team showed that the RNA sequenced from the Pleistocene-era canid was truly representative of the animal's RNA, with many liver-specific transcripts that matched more modern samples from both wolves and dogs.

The Siberian canid's transcriptome is the oldest RNA sequenced by far, surpassing the next oldest transcriptome by at least 13,000 years. The authors note that unlike paleo-genomics, paleo-transcriptomics is unlikely to become routine, because even in the best conditions, RNA is not as well preserved as DNA.

Nonetheless, there are likely to be a large number of other naturally frozen specimens for which deciphering the transcriptome is possible, opening up for researchers not just the genes of ancient organisms, but the flux of cellular activity encoded by the transcriptome.

"Ancient DNA researchers have previously been reluctant to attempt to sequence ancient RNA because it is generally more unstable than DNA, and more prone to enzymatic degradation," said Dr. Smith. "However, following our recent successes in sequencing ancient RNA from plant material, we speculated that a well-preserved animal specimen, frozen in the permafrost, just might retain enough material to sequence. To our delight, we found that not only did we find RNA from various tissues, but in some case the signal was so strong that we could distinguish between tissues in a way that makes biological sense.

"Knowing that RNA acts as an intermediary between DNA and proteins, both of which are more stable, it might be tempting to ask, 'so what?'. But we think the future of ancient RNA has great potential. For example, many of the most clinically relevant viruses around today have RNA genomes, and the RNA stage is often crucial to understanding the intricacies and complexities of gene regulation. This might have repercussions when discussing the environmental stresses and strains that drive evolution."

https://phys.org/news/2019-07-gene-trans...years.html



Journal Reference:
Oliver Smith et al, Ancient RNA from Late Pleistocene permafrost and historical canids shows tissue-specific transcriptome survival, PLOS Biology (2019). DOI: 10.1371/journal.pbio.3000166

Abstract
While sequencing ancient DNA (aDNA) from archaeological material is now commonplace, very few attempts to sequence ancient transcriptomes have been made, even from typically stable deposition environments such as permafrost. This is presumably due to assumptions that RNA completely degrades relatively quickly, particularly when dealing with autolytic, nuclease-rich mammalian tissues. However, given the recent successes in sequencing ancient RNA (aRNA) from various sources including plants and animals, we suspect that these assumptions may be incorrect or exaggerated. To challenge the underlying dogma, we generated shotgun RNA data from sources that might normally be dismissed for such study. Here, we present aRNA data generated from two historical wolf skins, and permafrost-preserved liver tissue of a 14,300-year-old Pleistocene canid. Not only is the latter the oldest RNA ever to be sequenced, but it also shows evidence of biologically relevant tissue specificity and close similarity to equivalent data derived from modern-day control tissue. Other hallmarks of RNA sequencing (RNA-seq) data such as exon-exon junction presence and high endogenous ribosomal RNA (rRNA) content confirms our data’s authenticity. By performing independent technical library replicates using two high-throughput sequencing platforms, we show not only that aRNA can survive for extended periods in mammalian tissues but also that it has potential for tissue identification. aRNA also has possible further potential, such as identifying in vivo genome activity and adaptation, when sequenced using this technology.

https://journals.plos.org/plosbiology/ar...io.3000166
[Image: wildcat10-CougarHuntingDeer.jpg]
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