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Posts Tagged ‘Canada lynx’

Edwardian-lynx-c-Bristol-Museum-Art-Gallery-600-px-tiny-April-2013

Ab4458 the Edwardian lynx. Photo (c) Bristol Museum & Art Gallery. From Tetrapod Zoology.  

An errant Canada lynx was killed in the English county of Devon in 1903.

Darren Naish writes in the Tetrapod Zoology blog:

For over 100 years, a potentially significant dead cat has been sat in storage in a British museum. Specifically, the specimen – the lynx Ab4458 – has been at Bristol Museum and Art Gallery ever since it was added to the collections there in February 1903, and what makes it significant is that it was shot dead after living wild in Devon, southern England. As revealed in a new paper published by Aberystwyth University’s Max Blake and a team of colleagues (myself, Greger Larson, Charlotte King, Geoff Nowell, Manabu Sakamoto and Ross Barnett), the specimen represents a historic ‘British big cat’, though with ‘big cat’ being used very much in the vernacular sense, not the technical one (Blake et al. 2013).

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For over 100 years, a potentially significant dead cat has been sat in storage in a British museum. Specifically, the specimen – the lynx Ab4458 – has been at Bristol Museum and Art Gallery ever since it was added to the collections there in February 1903, and what makes it significant is that it was shot dead after living wild in Devon, southern England. As revealed in a new paper published by Aberystwyth University’s Max Blake and a team of colleagues (myself, Greger Larson, Charlotte King, Geoff Nowell, Manabu Sakamoto and Ross Barnett), the specimen represents a historic ‘British big cat’, though with ‘big cat’ being used very much in the vernacular sense, not the technical one (Blake et al. 2013).

A lynx of any species would not technically be a big cat. The term “big cat” in the taxonomic sense applies only to the cats in the genus Panthera (the tiger, the lion, the jaguar, the leopard, and now, the snow leopard) and the two species of clouded leopard. All other cats are technically “small cats,” which means that the cougar, the largest of the small cats, is actually larger than the smallest of the big cats, the mainland clouded leopard.

This particular lynx caused quite a stir before it was it was killed.

Accession documents at the museum describe how it was shot dead by a ‘Mr Heb’ (the handwriting in the accession catalogue is difficult to read and this name might be wrong) after killing two dogs. It was then donated to the museum by a Mr J. Niblet of Newton Abbot, Devon. The geographical origin of the specimen is given as ‘Newton Abbot’. Foreign specimens are clearly marked with a place of origin, so we have to conclude that the cat really did come from Devon.

No one really paid much attention to this cat until 2011, when Max Blake, a student at the University of Bristol, found it while doing volunteer curatorial work at the museum. The animal was quite clearly not a Eurasian lynx, as everyone had initially assumed.

Blake, who was then studying zoology, knew it either had to belong to one of the two New World species of lynx, the bobcat or the Canada lynx.

But the animal appeared to have a mixture of both Canada lynx and bobcat features. The cat had just enough facial markings to suggest that it was a bobcat, and thus, it could have belonged to one of the northern subspecies of bobcat.

When I initially heard of this case back in 2011, I thought it was a northern bobcat, not just for those reasons, but because it is virtually unheard of for a Canada lynx to attack dogs. Bobcats, however, are much more aggressive animals, and in the wild, the larger subspecies are known for hunting mule and white-tailed deer. Canada lynx are rangier than bobcats, but they are actually lighter in weight than the largest subspecies of bobcat. And their diet consists of almost nothing but snowshoe hare. (Canada lynx are about the most bizarre cat species I can think of).

The researchers were unable to extract any DNA from the specimen, but the museum did still have its bones on file. After a careful morphological analysis of its skull, it was determined that the cat was indeed a Canada lynx.

This lynx had very worn out teeth, which suggests that is was of advanced age when it was killed. It also might explain why it was so willing to attack the dogs. It was desperate for some sort of sustenance, and dogs may have been the only suitable prey available.

Analysis of the teeth revealed it likely hadn’t been living on its own for very long:

Examined with all of this in mind, Ab4458 lost its incisors during its lifetime. New bone then overgrew the alveoli*. Thick build-ups of calculus are present on its lower and upper premolars. Based on this data, we conclude that Ab4458 suffered from periodontal disease and – based on all that calculus – lived a life of 10 or 11 (or so) years in captivity during which it fed on soft, non-abrasive foods. In conclusion, we couldn’t find any evidence here that the animal lived for a long time in the wild. Rather, it had been a captive animal for years (Blake et al. 2013).

So someone in Devon had been keeping a pet lynx for quite some time. It then was either released or got loose when it was about 10 or 11 years old.

My guess is this cat came from Newfoundland. Devon and Dorset were the English home counties for a large number of fishermen who fished off Newfoundland’s Grand Banks.  Newfoundland English is heavily influenced by the dialects from that part of England, where the people sound like stereotypical pirates.

Perhaps a Devon fishermen brought home a lynx kitten for his children as a souvenir from his travels. The cat was probably a beloved pet for a few months. Then maybe it got a bit aggressive, and its owners moved it to the backyard, where it remained for the rest of its life.

Until it escaped or was set free.

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Source.

Canada lynx and bobcats really don’t belong in the pet trade.

They might be somewhat easy to breed and feed, but their needs are usually too much for the average person. Most of the ones available on the pet market descend from ancestors that were bred for the fur trade.

And the fact that they are wild animals that have a lot of power for their size just makes the inappropriate as pets.

Declawing such animals might make sense in this context, but for a species that is known for producing such a copious undercoat, a Canada lynx needs all the grooming equipment at its disposal.

And never mind that declawing is a very painful procedure.

 

 

 

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These TheWildNorth videos are addictive:

Source.

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Canada lynx trapping

Source.

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Attracting a Canada lynx

This is a really good video about someone attracting a Canada lynx to the back of a cabin.

Source.

This is my favorite species of wild cat.

I think they are so beautiful with their gray pelts and tufted ears.

They have a sort of profound elegance one does not see in the bobcat.

It’s a frosty, steely presence that is hard to describe.

It’s the cat of the Great White North.

Gray as the boreal forest in January, it is the slayer of snowshoe hares.

Its wagon is attached to the hare’s wagon, and should the hare population crash, the lynx population soon follows.

But it will scavenge and even eat the flesh of its own kind.

It is only through this way that it’s been able to survive in the subarctic forests, where no other cats live or even dare to tread.

It is not beyond its nature for humans to be able to attract them with bits of meat.

I bet some old trappers and mountain men once dreamed of being able to tame them.

But we never have.

They come for the hand-outs, and then they melt back into the forest– wild phantoms whose world we can never fully understand.

 

 

 

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Lynx dogs

From Harper’s Young People (1880):

The large and powerful dogs which are found in Canada and the northern portions of Michigan, Minnesota, and other border States, where they are used as train dogs to drag the mail sledges over vast wastes of snow during the winter, are natural enemies of the lynx, and pursue it furiously through the snow-bound forests. Their loud barking often warns the hunter before he himself catches sight of the game that the desired prize is treed, and awaits its fate, with arched back and fur bristling, after the manner of an enraged cat.

The dogs depicted treeing this lynx are most likely of the farm shepherd- or farm collie-type.

These were dogs that were used for many different purposes– driving sheep and cattle, guarding the farms and homesteads, and hunting various game species.

It would make sense that someone with sheep would use dogs of this type to hunt a supposed predator of the stock.

I don’t know how often they would have attacked sheep.

My guess is not much. This animal prefers to live on snowshoe hares, and although it will hunt other things, if it has ample snowshoe hare populations, it won’t try to hunt much else.

These animals most likely became rare in the Lower 48 because of unregulated trapping for their fur. Note that I said unregulated trapping, for the Canadians and Alaskans have not made the lynx rare through their regulated trapping regimes.

In some parts of Canada, these animals aren’t just trapped and hunted for their fur. They are also taken for their meat, which is said to be quite good.

I’d like to try it.

It’s basically eating a big gray pussy cat, but it’s said to be a quite nice, lean meat.

But then you’re eating a cat, which some people erroneously think is going extinct. It’s endangered only in the Lower 48, not Alaska or Canada.

But because people just don’t know, you’re evil if you even suggest it.

But many a North Woods trapper or hunter has relied upon lynx meat to sustain him and his family through the long winter.

 

 

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Bobcat (top) and Canada lynx (bottom) from James Ellsworth De Kay's Preliminary List of the Mammals of New York (1842).

North America has two lynx species– the Canada lynx (Lynx canadensis) and the bobcat (Lynx rufus). Historically they have been regarded as being members of a single species that includes the Eurasian lynx (Lynx lynx), the largest and most widespread member of the genus in the Old World.

Both bobcats and Canada lynx evolved from the Eurasian lynx.  The lineage that led to the modern bobcat is believed to have diverged from the ancestral Eurasian lynx population around 2 million years ago.

The Eurasian lynx is a generalist carnivoran. It hunts a wide variety of prey, including deer and small rodents. It once ranged from the British Isles to the the Russian Far East and is found as far south as the Himalayas.

It widely varies in size from as little as 22 pounds to (officially) as much as 84 pounds.

These traits also exist in the bobcat species, which varies from as little as 9 pounds to as much as 49 pounds.

Note that the scale is much smaller for the bobcat than the Eurasian lynx.

Bobcats are essentially miniature versions of their Old World ancestor. They also hunt a wide variety of prey species ranging from mice to mule deer. The southern subspecies of bobcat are quite a bit smaller than those in the north of their range, which allows them to fill the niche of a small mesopredator. The northern subspecies are quite different, and in some areas, including West Virginia, they eat a lot of deer.

Bobcats evolved their smaller size as a result of the conditions during the last glacial maximum. They have only existed in their current form for about 20,000 years.

The advancing glaciers kept the gene flow from other ancestral Eurasian lynx from entering North America, but eventually, another wave of Eurasian lynx migration happened in the northernmost part of North America. It is not clear exactly when this happened, but the lynx population that colonized this part of North America evolved very differently from the bobcat. These cats likely evolved in the northern part of the continent that was at times free from the ice sheets but were still separated from the bobcats by glaciers that were further to the south.

Whereas the bobcat had retained much of its ancestor’s generalist behavior, these northern North American lynx became specialists. Perhaps the only prey available for lynx living in the far north were snowshoe hares, for these lynx became very much adapted to hunting only that prey.

These lynx became the modern Canada lynx, which is sometimes incorrectly called the “Canadian lynx.”    If a bobcat and a Canada lynx are in Canada, they are both Canadian lynx, just as if you find a Canada goose and a snow goose in Canada, they are both Canadian geese. But the actual species for both the goose and the lynx are “Canada goose” and “Canada lynx.”

Throughout its range, Canada lynx are almost entirely dependent upon snowshoe hares for sustenance. Snowshoe hares are prone to boom and bust cycles of population growth, and the Canada lynx population largely tracks snowshoe hare populations.

Because it hunts almost nothing but snowshoe hares, the Canada lynx is also smaller than the Eurasian lynx, but unlike the Eurasian lynx and bobcat, its size variance is more conservative, generally weighing only between 18 and 24 pounds. It is a longer legged cat than the bobcat, and it generally weighs more than the majority of bobcats. However, the largest bobcats are larger than the typical Canada lynx.

The only place in North America where Canada lynx existed without snowshoe hares was Newfoundland, and here the Canada lynx either re-evolved its generalist habits and somewhat larger size or it is the one subspecies of Canada lynx that has retained the generalist habits and phenotype of its Eurasian ancestor. Whatever the case, the Newfoundland subspecies of Canada lynx is known to attack caribou, but its numbers were always quite low in Newfoundland, leading some to speculate that the Canada lynx was never native to the island.

This all changed when snowshoe hares were introduced to the island between 1864 and 1876.  The hares were introduced as a supplemental food species for colonists on the island, and when the hares arrived, they were without any competition. Arctic hares lived in the north and west of Newfoundland, but they have very different habits from snowshoes.

The snowshoe hares thrived and greatly multiplied, and the Canada lynx population skyrocketed along with the hares. By the early 1900′s, the snow shoe hares had thoroughly colonized the island.

Then, they reached their carrying capacity, and as normally happens on the mainland, the snowshoe hare population began to drop. Leaving behind lots of hungry Canada lynx.

As I noted before, the Newfoundland subspecies of Canada lynx is capable of hunting caribou.

And many of the cats started doing just that.

And then the caribou numbers began to drop.

However, initially no one knew that the Canada lynx was somehow implicated in reducing caribou numbers.

Many caribou were dying as young calves– from bizarre bacterial infections that were almost always accompanied by some weird puncture marks on the neck.

It took a while to figure out that these bacterial infections were coming from failed predation attempts by Canada lynx. The puncture marks on the necks were those of the lynx’s teeth, which, for whatever reason, didn’t often produce a killing bite.

When it was discovered that Canada lynx were reducing caribou numbers, lynx trapping and hunting limits were liberalized, and there was an increase in the endemic Newfoundland caribou herds.

(You can read more about the Canada lynx, hare, and caribou dynamic on this post. It took only the introduction of snowshoe hares to disrupt the whole predator-prey dynamic in Newfoundland.)

But with the exception of Newfoundland, Canada lynx are not implicated as being any kind of major predator to large ungulates.

The larger subspecies of bobcat, however, do take deer on a relatively regular basis.

These larger bobcats are actually much more aggressive than Canada lynx, and where their ranges overlap, the bobcats generally dominate the lynx.

The range overlaps over most of the Canada lynx’s range in the United States and in the southern tier of Canada.

And not only do bobcats dominate Canada lynx, there is also evidence of introgression of bobcat genes into the Canada lynx population. As of 2008, seven Canada lynx/bobcat hybrids were documented in the states of Maine and Minnesota and the province of New Brunswick. Non-overlapping allele frequency analysis revealed that these cats all had some bobcat ancestry, and mtDNA evidence revealed that they all had a Canada lynx as a mother. One queen had three kittens, which shows that hybrids are able to reproduce in the wild, and another queen had placental scars in her reproductive tract.

The male-female combination in the hybrids is pretty similar to what we know about the the behavior of the two cats.  Bobcats are  just much more aggressive than Canada lynx. Because the female bobcat is quite aggressive, it would be very hard for a male Canada lynx to mate with her, but the male bobcat is aggressive enough to drive male Canada lynx away from their mates.

Of course, there is some suggestion that bobcats are starting to thrive in lynx habitat because of climate change, and that very well may be. But Canada lynx once were found very deep into bobcat range. In the Eastern US, they ranged as far south as West Virginia, which does have a population of snowshoe  hares. Perhaps during the Little Ice Age, snowshoe hares were much more widely distributed in West Virginia than they are now, which allowed the Canada lynx to colonize this far south. There is also some possibility that there were very large Canada lynx type cats in the Alleghenies, as this historical record suggests. Perhaps these large gray lynx were an offshoot of a Canada lynx population that moved south and evolved to hunt deer– or maybe they were a primitive Canada lynx that still possessed their ancestral Eurasian lynx size.  (Or it could have been a damn tall tale. Never discount that possibility!)

If Canada lynx ranged this far south, then there likely would have been a gene flow between bobcats and lynx.   It is possible that there could have always been some hybridization between the species once the glaciers separating the two were gone.

We honestly don’t know how much hybridization has happened between bobcats and Canada lynx. Currently, the suggestion is that hybridization isn’t common, but the genetic studies on bobcats and Canada lynx are somewhat limited– especially when compare them to wolves and coyotes, which recently were recently examined in the most in depth genomic assay ever performed on wild animals.

Something similar to the genome-wide study on coyotes and wolves needs to be performed on Canada lynx and bobcats. If one were peformed, I bet we’d find that those two animals have exchanged genes quite a bit in the past and continue to do so now. Perhaps they even have a species complex.

Roughly two million years of evolution separates the bobcat from the Canada lynx, which is more closely related to the Eurasian lynx than the bobcat.

But two million years may not be enough separation for the two cats to regard each other as separate species.

The little generalist lynx of North America meets its gray, hare hunting cousin.

The exact taxonomy of the two species has remained contentious for decades.

Initially they were regarded as different subspecies of lynx– and were conspecific with the Eurasian lynx.  Later, they Canada lynx was made a subspecies of Eurasian lynx, and the bobcat was moved into the house cat genus– Lynx rufus became Felis rufus.

Currently, we recognize that bobcats and Canada lynx are close relatives. Both derive from the ancestral Eurasian lynx, but both of these North American derivatives has gone its own way.

At least in the aggregate.

They have gone their own way.

But they have also converged.

How much they have converged is anyone’s guess– more studies need to be peformed.

But the genus Lynx has had a remarkable evolutionary history in North America.

And it may have a remarkable evolutionary future.

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The following description is of a giant gray lynx that was killed in Pennsylvania in 1874. It comes from Henry Wharton Shoemaker’s Extinct Pennsylvania Animals (1919) :

John G. Davis, old-time woodsman of McElhattan, Clinton County, gives the best description of a mammoth Canada Lynx killed by John Pluff at Hyner, in that county, in 1874. Pluff, who was a noted hunter in his day, died in January, 1914, in his 74th year. One evening, when Pluff was at supper, he heard a commotion in his barnyard. Taking down his rifle, he hurried out, only to notice a shaggy animal moving about among the feet of his young cattle. Courageously driving the steers into the barn, he came face to face with a gigantic Canada Lynx, or, as was called in Northern Pennsylvania, a “Big Grey Wild Cat,” or catamount, to distinguish it from the smaller and ruddier Bay Lynx [bobcat].

Taking aim at the monster’s jugular, Pluff fired, killing the big cat with a single ball. The shot attracted the neighbors, among them Davis, and they gazed with amazement at the giant carcass, the biggest cat killed in those parts since Sam Snyder slew his 10-foot panther on Young Woman’s Creek in 1858. The Canada Lynx measured 4 feet, 10 inches from tip of nose to root of tail—(the tail measured 4 inches)—and weighed 75 pounds.

The next day being Thanksgiving, it was supplemented to the turkey feast, and all enjoyed the deliriously flavored white meat more than the conventional “Thanksgiving bird.” This lynx was probably a straggler from the Northern Tier, as none of its kind have been about Hyner since. At the same time, the Canada Lynx has been killed in many parts of Pennsylvania, as far south as the Seven Mountains and Somerset County, some claim, but never frequently. It hangs close to the main chain of the Allegheny Mountains, if it can make a living there (pg. 183-184).

Now, this story should be taken with a grain of salt.

Exaggerated sizes for large predators are almost de rigueur for frontier stories.

But I don’t dismiss it out of hand.

The typical Canada lynx is big at about 40 inches in length, and it weighs only 18 to 24 pounds.  They are rangier than bobcats, but they will weigh less than the biggest bobcat.

This 75- pound  “lynx” in Pennsylvania doesn’t sound like a Canada lynx to me at all.

The truth is we really don’t have a good handle on the native mammals of North America that lived before the modern conservation movement.

I think it is very possible that there were very large lynx in the United States. This animal could have been a very large gray bobcat, for bobcats are well-known to vary greatly in size. Canada lynx actually don’t. Throughout their range, they are essentially the same size– 18-24 pounds.

This particular cat– if it did weigh 75 pounds– probably wasn’t built like the rangy Canada lynx we know today. It would have had to have been a particularly robust creature.

Or it could have been a unique species of lynx that we never were able to document before it became extinct.

There is the persistent story of the Ozark howler, a giant black bobcat that lived in the mountains of Arkansas and Missouri, and I think it might be possible for European man to have made it impossible for large lynx and bobcats to survive.

After all, a farmer is much more likely to tolerate a 25-pound bobcat than a 75-pound bobcat or lynx.

Eurasian lynx to reach this size, and they are very effective predators of deer.

And it is well-known that bobcats and Canada lynx evolved from the Eurasian lynx.

Traditional accounts say that the bobcat became diminutive to avoid competition with already extant large predators in North America, and the Canada lynx invaded the continent in a later wave, where it became established in the Northern part of the continent as a snowshoe hare specialist.

But could there have been large lynx-type cats in North America in modern times?

I don’t know how good the evidence is, but we do have these tantalizing historical accounts that make us wonder.

Maybe there were large bobcats and/or undocumented lynx species in North America during an earlier time, and these animals were wiped out because of the potential threat they posed toward livestock.

Again, I am very skeptical that this cat was a Canada lynx. Canada lynx are actually quite poor at preying upon livestock and deer. Bobcats are actually much better at it.

The size of this animal could be a mere exaggeration, but we do have Eurasian lynx that are that size.

So it’s possible.

But what it exactly was is still a unanswered and unanswerable question.

It’s fun to speculate, eh?

I can’t decide whether it’s a mere exaggeration or if there actually was a lynx or bobcat of that size.

It’s up in the air for me!

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I had never actually looked at the historic range for the Canada lynx, and I was more than a little shocked to find this map from the National Geographic Society.

They were here!

I then came across some analysis  that claims that Virginia was within the cats’ historic range, but this may be slightly in error.

When the lynx where here, this region was within the Commonwealth of Virginia, which became the union state of West Virginia in 1863.  Virginia, in case you didn’t know, was busy trying to be part of another country in 1863.

One must keep in mind that the distinctions between Canada lynx and bobcats were not as clearly defined as they are now. I have come across sources that talk about a lynx in Texas, which most obviously was the bobcat.

The two cats are actually quite closely related and can interbreed and produce fertile offspring. They very rarely do so in the wild, because bobcats are much more aggressive with each other than Canada lynx are.

Contrary to what you may have read, Canada lynx are not necessarily larger than bobcats either. The bobcat varies much more in size, and many bobcats, especially in the subtropical parts of the South, are quite small animals, only weighing around 10 to 15 pounds. However, the biggest bobcat on record was much larger than this. It was shot in Marinette County, Wisconsin, and it weighed over 48 pounds. The Canada lynx is usually in the 18-25 pound range.  The northernmost bobcats are  generally larger than Canada lynx.  The reason why people think they are much larger is that Canada lynx have much longer legs than a bobcat.  Longer legs and thicker fur give the illusion that the Canada lynx is the same size as a mid-sized dog.

Besides human depredations and habitat loss, there are several reasons why the Canada lynx isn’t found in much of the United states anymore. Bobcats are much more adept at killing large prey than Canada lynx, which is a snowshoe hare specialist. Snowshoe hares aren’t as widespread in the East and Midwest as they once were. In West Virginia, there are fears that snowshoe hares could become very rare in the near future, and if lynx and bobcat were to ever compete, the lynx would be much more tightly regulated by snowshoe hare numbers. Bobcats, being the generalists of all generalists, would be able to take other prey.

But even at that, I can tell you that my grandpa actually saw a Canada lynx while turkey hunting.

He told me it was the size and color of Norwegian elkhound. He initially mistook it for a dog of that belonged to someone he knew in that area. The cat probably didn’t weigh as much as an elkhound, but they are about the same height at the shoulder. If the lynx had been thickly furred, it would have contributed to its elkhoundish appearance.  Elkhounds are not cats with short tails, and they lack the very large tufts on the ears, which also would suggest that this animal was not a bobcat.

My grandpa was always very clear that it wasn’t a bobcat. Bobcats are relatively common in this part of the world, and the main color phase of the bobcat here are very thickly speckled. At at distance, Canada lynx appear almost pure gray in color.

What was it doing in West Virginia?

It could have been from a relict population, but this is unlikely. There are no snowshoe hares in the part of the state where he encountered it, and if one were to ever find native lynx in West Virginia, it would almost have to be found in prime snowshoe hare territory.

These cats do disperse a long way from their mother’s territories– especially young toms. It is possible that one from Canada or the Great Lakes states could have wandered down.

But I think it is much more likely it was one that had originally been kept as a pet and then released into the wild.

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From Science Daily:

As wolf populations grow in parts of the West, most of the focus has been on their value in aiding broader ecosystem recovery — but a new study from Oregon State University also points out that they could play an important role in helping to save other threatened species.

In research published in Wildlife Society Bulletin, scientists suggest that a key factor in the Canada lynx being listed as threatened under the Endangered Species Act is the major decline of snowshoe hares. The loss of hares, the primary food of the lynx, in turn may be caused by coyote populations that have surged in the absence of wolves. Scientists call this a “trophic cascade” of impacts.

The increase in these secondary “mesopredators” has caused significant ecosystem disruption and, in this case, possibly contributed to the decline of a threatened species, the scientists say.

“The increase in mesopredators such as coyotes is a serious issue; their populations are now much higher than they used to be when wolves were common in most areas of the United States,” said William Ripple, a professor in the Department of Forest Ecosystems and Society at OSU.

“Before they were largely extirpated, wolves used to kill coyotes and also disrupt their behavior through what we call the ‘ecology of fear,’” Ripple said. “Coyotes have a flexible, wide-ranging diet, but they really prefer rabbits and hares, and they may also be killing lynx directly.”

Between the decline of their central food supply and a possible increase in attacks from coyotes, the Canada lynx has been in serious decline for decades and in 2000 was listed as a threatened species. It also faces pressure from habitat alteration, the scientists said, and perhaps climate change as lower snow packs further reduce the areas in which this mountain species can find refuge.

In numerous studies in recent years, researchers have documented how the presence of wolves and other large predators helps control populations of grazing ungulates including deer and elk, and also changes their behavior. Where wolves have become established, this is allowing the recovery of forest and stream ecosystems, to the benefit of multiple plant and animal species.

Lacking the presence of wolves or other main predators in both terrestrial and marine environments, populations of smaller predators have greatly increased. Other studies have documented mesopredator impacts on everything from birds to lizards, rodents, marsupials, rabbits, scallops and insects. This includes much higher levels of attacks by coyotes on some ranch animals such as sheep, and efforts attempting to control that problem have cost hundreds of millions of dollars.

Scientists have concluded that exploding mesopredator populations can be found in oceans, rivers, forests and grasslands around the world.

“In the absence of wolves, coyote densities and distributions generally expanded in the U.S., into the Midwest, to the northeast as far as Newfoundland, and as far northwest as Alaska,” the researchers wrote in their report.

Where wolves recovered, as in Yellowstone National Park, coyote populations were initially reduced by 50 percent, Ripple said. Although more sampling will be required, early evidence indicates that a snowshoe hare recovery may be taking place.

As these issues are factored into decisions about how to manage wolves, the researchers said, it’s also important to maintain what they call “ecologically effective” wolf populations, the researchers wrote in their study. The full value of these top predators, and the numbers of them it takes to achieve a wide range of ecological goals, should be more thoroughly researched and better understood, they said.

The issue of “mesopredator release” has been studied rather extensively in recent years.

My favorite study on mesopredator release happened in suburban Southern California.  Michael Soule found that in areas where suburban coyotes frequented, there were more songbirds. Why?   The coyotes in this environment where not the mesopredators. They were the apex predators, and they served the songbirds well. Domestic cats, both owned and feral, are known to be major predators of native birds, but in North America, their kryptonite is the coyote. Coyotes eat lots of cats in suburban environments. And the cats, not being fools, know to avoid areas where they might meet a coyote. It is in those areas of suburban Southern California where songbirds nest.  Coyotes really don’t care about bird nests, especially if they are up in trees, but they do care about cats.

In addition to the possible assistance that wolves could provide Canada lynx, it also been established that wolves have helped pronghorns fully establish themselves in Yellowstone.  When wolves were extirpated from the Yellowstone region, the coyote population shot up, and the coyotes began to take advantage of many different predation opportunities. When the female pronghorns dropped their fawns, the coyotes would swarm in and catch them. This predation prevented pronghorns from ever establishing the large numbers that had been expected for the species at Yellowstone.

When wolves were reintroduced, the coyote population was halved, and the coyotes tended to stay out of the open areas around the Lamar Valley, where the pronghorns gave birth to their offspring every year.

If wolves succeed in reducing the Canada lynx’s problems from coyotes, it will be a good thing for this species. It is not very common in the United States anymore, but it once ranged rather extensively through the northern tier and down the Rockies.

These lynx do exist in Canada at fairly large numbers, where there are also plenty of wolves. Wolves and Canada lynx really are not competitors. Canada lynx are almost entirely snowshoe hare specialists, and they tend to inhabit much more densely wooded places than wolves do.

However, coyotes do frequent these very densely wooded areas, and they are not above killing a lynx’s kittens.  An adult Canada lynx could kill a coyote on its own, but if confronted with a family group of coyotes, my guess is the lynx wouldn’t stand and fight.

The real problem with Canada lynx and coyotes is the same that existed between dingoes and thylacines. Canada lynx are too specialized to one species of prey, while coyotes are generalists, taking not only the lynx’s specialist prey but also other species, which allows their numbers to exploded. In Australia, the thylacines were specialized in hunting small macropods and other smaller prey, but when the dingo or proto-dingo arrived in Australia, they were able to hunt both large and small prey. They were able to take most of the thylacine’s prey from it and augment their diet with large macropods.

Specialization has proven to be the death of so many species, and it would be a shame if the generalist coyote would push the Canada lynx over in this fashion.

So maybe if the wolves do keep the coyotes down, the great northern cat can once again be on the increase.

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