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Archive for the ‘Carnivorans’ Category

A red fox vixen in the Mid-Atlantic part of the USA. Photo by Kris Diaz.

A red fox vixen in the Mid-Atlantic part of the USA. Photo by Kris Diaz.

Red foxes are currently the most widespread wild canid.

This is the same sort of fox that can be found in Egypt, England, and Virginia, and it has been introduced to Australia, where it has become a virulent invasive species, taking out scores and scores of endemic native wildlife.

For many years there was a debate about how to classify the red fox in North America. Unlike Australia, where there is no real case for calling it native wildlife, North America’s red fox population has been a bit controversial.

When the tobacco colonies along the Chesapeake created America’s first landed gentry, there was a move to import well-bred foxhounds for sporting purposes. At that time and in that part of the continent, there were no native red fox populations, so there were accounts English red foxes being introduced to the Virginia Tidewater and the Maryland plantations for sporting purposes.  Red foxes were found in northern New England at the time, so I’ve often wondered why they didn’t just get their foxes from those colonies.

For a very long time, it was just assumed that red foxes living south of New York State were derived from English foxes that were brought over in the seventeenth and eighteenth centuries.

After all, the Australian red foxes were definitely derived from introduced individuals, so it would make sense that there could be an introduced population in the Eastern US.

However, red foxes are found over much of the continental US and Canada, and there are Pleistocene records of red foxes in Virginia.

So red foxes definitely are native to this continent, but the question is whether those in the Eastern US are derived from native populations or from those English imports.

In the early twentieth century, virtually all red foxes in North America were classified as Vulpes fulva, rather than Vulpes vulpes.

But as time progressed, all North American red foxes became classified as Vulpes vulpes, and the Eastern and Midwestern population of red fox became Vulpes vulpes fulva.

Then two papers came out that examined the DNA of red foxes across the continent and in Europe.

In 2012, Stratham et al.  found that their mtDNA of Southeastern and Mid-Atlantic red foxes was very similar to those in Eastern Canada and the Northeastern US, meaning those populations were indigenous North American foxes. They descended from foxes that came into that part of the continent during in the nineteenth century in much the same way coyotes invaded the East in the twentieth century.

Then, in another Stratham et al (2014) paper, it was revealed the Old World and New World red foxes have been reproductively isolated for 400,000 years. This paper also looked at the y-chromosomes and nuclear DNA of 1,000 red foxes from around the world, and it strongly suggests that there are actually two species of red fox. There was some evidence of Eurasian red foxes entering into the Alaskan red fox population 50,000 years ago, but other than that, these two animals might as well be separate species.

Now, I’m a little hesitant to consider that red foxes should be split in two in this fashion, but keep in mind, that in North America, there are two species of Urocyon fox, the mainland gray fox and the island fox. But analysis of mtDNA from both types of Urocyon revealed that the island population only split from the mainland species somewhere between 7,100 and 9,200 years ago.

The lower estimate of that split is at least half the time that dogs and wolves have been split.

And it’s nowhere near the time in which New World and Old World red foxes have diverged.

If we are so willing to have two species of Urocyon, then there is way that we can have just one species of red fox.

The case that these two types of red fox are different species is just so much stronger than the island fox’s taxonomic distinctiveness.

Of course, I actually do question the taxonomic validity of the island foxes. Some of these island fox populations are so inbred that they could stand to have mainland gray foxes introduced for genetic rescue purposes, but because they are a species in the eyes of the Fish and Wildlife Service, no one seriously considers the possibility.

But when it comes to red foxes, two things are clear:

They are native to this continent and are not English imports.

And they haven’t exchanged genes with the Old World red foxes in a very long time.

So there really is a strong case that our red foxes are Vulpes fulva and not Vulpes vulpes.

But there aren’t wide morphological differences between the two populations. Red foxes in Europe pretty much look like the red foxes of the Eastern US. In fact, North American and northern Eurasian red foxes look much more similar to each than either looks like the Middle Eastern and North African subspecies of red fox.

Red foxes in Eurasia and North America pretty much share the same niche as generalist mesopredators. Both types have successfully colonized suburban and even urban environments.

Those are the traits we see.

But their DNA says we’re looking at two quite distinct populations.

It’s counter-intuitive.

But it is strangely fascinating.

 

 

 

 

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Bobcat poo turns chalky white when it gets old. There is a lot of calcium carbonate in the feces, which means they turn chalky when left exposed for a few days.

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Too cute fox!

Look at that face!

Source.

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This week we had several visitors on the trail cameras. Keep in mind that one of these cameras has a messed up clock, so the time stamp reads that the video was taken in 2068. These cameras are pretty good technology, but they aren’t that good!

Let’s start small.  Here’s a white-footed mouse or a deer mouse:

Source.

I can’t tell whether it is a white-footed mouse or a deer mouse, which is hard enough to do in the broad daylight. These animals are in the genus Peromyscus, and although we call them mice, they aren’t closely related to the mice that originated in Old World.  New World rats and mice are more closely related to voles, hamsters, and lemmings than to house mice and Norway rats.

Then we got a light-colored opossum:

Source.

A good close-up of a melanistic gray squirrel:

Source.

And a large raccoon:

Source.

Because of the size of the raccoon, I am assuming that this one was a male. He was coming to inspect a pile of sticks and logs that I have anointed with weasel lure.

 

 

 

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Source.

The uploader of the video describes the fox as a “silver fox.”  This isn’t correct at all. This is a gray fox, genus Urocyon, which is not a true fox at all.  It is actually the most genetically distinct species of dog still existence today. It last shared a common ancestor with the rest of the dog family 9 to 10 million years ago.  Gray foxes are known for their tree-climbing behavior, which is one of their hallmarks. Indeed, another name for this fox is the “tree-climbing fox” or “tree fox.”

Silver foxes are actually a phase of red fox. When I first watched the video, I was expecting to see a silver phase red fox, but the shrieks very quickly told me that this uploader had misidentified the species. This is pretty common. Silver and normal phase red foxes do interbreed, but you might as well try to cross a red fox with a hamster than try to cross red and gray foxes.

A fisher is a large North American marten. North American martens are not closely related to Eurasian martens, but they look similar to them. In fact, both North American marten species are more closely related to wolverines than to pine and beech martens which they superficially resemble. The term “fisher” comes from a mistranslation of the French word for polecat, which is fichet. French trappers sold fisher pelts as polecat pelts, and the name just sort of got stuck with them. They don’t fish at all. They hunt porcupines and squirrels and have been known to take white-tailed deer fawns on occasion.

The fisher’s range is currently expanding. They are now becoming more and more common in the Eastern US, and in my state, where they were extirpated, they are now making a strong comeback.

They live in pretty much the same habitat as gray foxes and hunt a lot of the same prey, so I have actually been thinking how these two species would interact. My guess is they would be hot competitors, and this video suggests that I might be right. I don’t know if there are any studies on fisher and gray fox interactions, but as fishers expand their range deeper in the gray fox’s core range, there will be lots of interactions like this one.

The “lesser” carnivora don’t get much attention as the big ones do, but their behavior and ecology are every bit as fascinating.

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Bounding weasel

Weasels bound, so they make tracks that look like two little feet. But what really happens is they put their front feet down and then move their back feet into the same place where their front feet were as they bound forward.

My guess is this was a least weasel, because it was awfully small.

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This weasel likely came through just before it started to snow yesterday, because its tracks are nearly filled in. There was a whole line of tracks just like these going from one side of the access road to the other.

 

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In late October 1999, my grandpa, also named Scottie Westfall, was out squirrel hunting. While staking out one of his favorite stands of hickory,  he heard brush cracking and a rabbit screaming.  Suddenly, a cottontail rabbit came running down a game trail. The rabbit stopped at little copse of brush, just a couple of yards from where my grandpa was staking out the squirrel trees.

Usually when one sees a rabbit running down a trail, something is pursuing it.

In this forest, the rabbits get pushed hard by the red and gray foxes, and the coyotes do take more than a few.

So my grandpa waited with his eyes trained on the trail from whence the rabbit came.

Just a few minutes later, something small and white came jumping along. It followed the rabbit’s trail perfectly and then went into the brush where the rabbit was.

The rabbit bolted before the creature could come near, and after white beast sniffed out the little copse of brush, it began to sniff around to see if it could pick up the rabbit’s trail again.  It soon did and started hunting again, and as it came along it happened to raise its head above a log.

Which created the perfect shot opportunity.

My grandpa shot the animal and realized it was some kind of weasel. However, it was quite a bit larger than the common least weasel that he knew so well, and what’s more, the weasel was almost entirely white.

My grandpa thought he knew all the animals of these woods pretty well. Weasels were the bane of the chicken coops when he was a boy, and he told me about trapping a few of them for their fur.

He also told me of how he illegally ferreted with an albino ferret, using him in groundhog dens and abandoned pipe to drive out cottontail rabbits that sought refuge from extreme cold or barking dogs.

But he’d never seen a white weasel before.

I vaguely knew that there were white weasels in the United States. I had read all about ermines and something called “Bonaparte’s weasel” that turned white in winter.

But teenage me just decided it was an ermine, and we left it at that.

He did a informal survey of all his hunting buddies, and none of them had ever heard of an ermine or a white weasel.

It’s been in the freezer ever since. I knew there was something odd about it.

I’ve written about it on the blog before.

I’ve come to the conclusion that it was a long-tailed weasel.

I don’t want to make this confusing, but in the Eastern US, there are two weasels that turn white in the winter. The ermine or short-tailed weasel is the one that Old World readers might know as a stoat. Most stoats from the British Isles don’t turn white in winter. This species is found throughout Eurasia and North America, but it has never been recorded in West Virginia. It comes only as far south as Pennsylvania. An old name for this weasel is Bonaparte’s weasel.

The long-tailed weasel is found in North and South America.  It does turn white in winter, but not all of them do. The Maryland/Pennsylvania border seems to be the geographical separation between weasels that turn white in winter and those that don’t. And in Pennsylvania and Ohio, not all weasels turn white.

Last week, I was contacted by a researcher from North Carolina State University, who is working on a study of snowshoe hares in the High Alleghenies. One of their research questions involved West Virginia’s long-tailed weasel population and their perennial brown pelage.

If you look up white weasels in West Virginia on Google, you wind up at my blog.

So I met with this researcher in Elkins, and it turns out that this weasel is a real weird one.

If you look at the logic of the two potential winter white weasel species I suggested, there are two main possibilities about what this animal could be.

It’s either an errant long-tailed weasel that doesn’t realize that just happens to have the genetics to turn white or it’s the first documented ermine in West Virginia.

I think the former is more likely.

But that’s not where it gets really bizarre. This weasel was not killed in the Allegheny Highlands, where the snow cover lasts the longest every year. It is certainly true that some of the higher elevation places in West Virginia are more like Maine or Eastern Canada, and one would think those places would be full of weasels that turn white in winter.

This weasel was killed in the Allegheny Plateau, and in the late 90’s, the winters were so mild that there was virtually no snow cover at all in this part of the state.

So why would a weasel turn white?

These woods where this weasel roamed are full of barred owls and red-tailed hawks that would love nothing more than have weasel to eat. A white weasel on the forest floor would just be advertising itself to the winged predators.

So this weasel raises many questions.

Soon, I’ll be setting out weasel gland lure with my trail camera to see if there are other weasels like this one in the area. Maybe there is an anomalous population of weasels in this part of West Virginia.

Or maybe this one was just a fluke.

Whatever it was, this weasel is a mystery. Some may give my late grandfather hell for shooting this weasel, but if he hadn’t shot it, we wouldn’t have this specimen, which might be the first record of a weasel molting to white in a population south of Pennsylvania.

Charles Darwin got into natural history as a recreational shooter. He traveled around the world on the Beagle killing unusual animals left and right.  He killed the South American fox species that bears his name with geological hammer.

If Hornaday had not killed the “big old ‘gator of Arch Creek,”  we wouldn’t have known that crocodiles lived in Florida.

My grandfather was pretty well-versed in natural history, and I think that if he were alive today, he would be impressed that this animal he killed while squirrel hunting would raise so many questions– and be such an anomaly.

 

 

 

 

 

 

 

 

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