Caturday felid: the missing lynx

An email from a reader, complete with new pictures of cute wild cats, prompted me to throw this week’s spotlight on the Canada lynx.

There are four species in the genus Lynx, two of which (the Canada lynx, L. canadensis, and the bobcat, L. rufus) occur in North America. The bobcat—once lumped with the Canada lynx in a single species—is far more common in the U.S.  Most Canada lynx live farther north, where they prey on snowshoe hares and other mammals. (The tandem and regular oscillations of lynx and hare abundance, with a cycle of about ten years, is a famous story in ecology, which, as far as I know, is still unexplained.)  Like most wild cats, they’re shy and solitary, so their biology is not terribly well understood.

Both American lynxes are medium-sized cats (20-30 lb) with tufted ears, very short tails (hence the name “bobcat”), huge paws (which, as you’ll see in the video below, act as snowshoes in winter), and a bushy mane around the jowls that gives them a regal and leonine appearance:

Peter Vickery, a biologist and president of The Center for Ecological Research, kindly agreed to share his story (and the three following photos) about surveying the Canada lynx in his state:

I was invited by the Maine Dept. of Inland Fisheries and Wildlife and USFWS researchers to join them looking for Canada Lynx dens in northern Maine.  The Lynx Team (MDIFW and USFWS) has been studying lynx in northern Maine for 11 years, documenting breeding and productivity, survivorship, and habitat use.

To determine productivity, the Team has put radio collars on a number of females. If the females are denning, their movements become very limited in May and early June.  When the general area of a potential den is identified, several members of the Team try and locate the female using receivers.  One member then goes in slowly to search for the den.  This often requires a game of approach and departure.  Once the team member gets reasonably close, the female lynx often moves off.  The researcher then moves off and the lynx returns.  By doing this several times and carefully following the female’s movements, the researcher can get a pretty good idea of the search area and then the slow process of working through dense regenerating clearcuts begins.

My impression and conversations with Team members indicate that dens are nearly always in regenerating clearcuts or heavy brushy blowdowns.  Lynx clearly use clearcuts as denning habitat, presumably because the hare densities are high and nearby, and the dense cover provides excellent shelter for a den.  The industrial forest in northern Maine appears to provide plenty of early successional habitat for hare and lynx.

On the day I joined the Team in mid-June, we failed to find a den in the morning because that particular female moved about in an irregular fashion and it was impossible to pinpoint a potential den site.  We tried a careful sweep and found old den sites but it may have been that the female had moved the kits, as they often do once the kits are old enough to move.

The second den search was successful, as you can see.  The Team uses medical gloves as they take a variety of measurements before the kits are returned to the den.  The Team then monitors the female’s movements to make sure she returns to the den.  The Team has never had a case of den abandonment.  Sometimes the females are close enough, within 4 meters, to observe the Team handling the litter but they are usually some 30 – 50 meters from the den while the Team is present.  I’m guessing the female does a huge amount of licking once she returns!  Despite efforts to minimize human contact, there must be some foreign smell that a diligent mother would want to remove.

It appears that 2010 is a pretty good year for lynx productivity in Maine.  Litters this year are in the 2 – 3 kit range where a few years previously some females didn’t have any offspring.  Litter sizes were larger earlier in the study.  Not surprisingly, the number of kits is very closely linked to hare densities.  I can attest to reasonable hare numbers this year as I saw well over 150 animals on a 60 mile evening drive along the wood roads the night I left the Lynx Team.

The Lynx Team follows the family in the winter once there is snow on the ground.  Because the adult female has a collar, the Team can find where they cross a wood road and then back track to determine how many young are still with the female.  I was impressed that this was an effective way to monitor kit survivorship through the first winter.  The Team always back tracks so they don’t interfere with the animals.  Females separate from the young lynx as the new breeding season approaches in early spring.

Regrettably, this is the last year of the study.  It’s clear they have gathered an enormous amount of important information relating to productivity and habitat use.

I was very grateful to accompany the Maine Lynx Team and was enormously impressed with their skill, perseverance, and care for the rare animals they were studying.  This was a very dedicated and caring group of field biologists!  It was a privilege to join them.

Here’s Peter with one of the babies:

I’ll close with one of the most impressive wildlife pictures I’ve ever seen:  a lynx catching a snowshoe hare, photographed by Robert Walch for the Time-Life book The World’s Wild Places: The American North Woods (1972).  Look at the size of those paws!

And two lynx videos.  The first is the classic duel between lynx and snowshoe hare:

And here’s a seriously peeved lynx. The book Wild Cats of the World reports that these beasts make a variety of sounds, some of them completely unexpected.  This one (which may be a bobcat) seems to be growling and bleating at the same time.

h/t: Peter Vickery, Scott Hedges

25 Comments

  1. Jonn Mero
    Posted July 31, 2010 at 5:40 am | Permalink

    Just out of curiosity, would a lynx kill and eat a house cat?

    • Posted July 31, 2010 at 7:09 am | Permalink

      I’m sure they would. But here in Vermont’s Northeast Kingdom (marginal lynx habitat) outdoor cats are far more likely to fall prey to fishers and coyotes.

  2. Posted July 31, 2010 at 5:49 am | Permalink

    I’m now perilously suspicious of my two Maine coons.

  3. Hempenstein
    Posted July 31, 2010 at 6:56 am | Permalink

    Are the ear tufts sexually dimorphic?

    • whyevolutionistrue
      Posted July 31, 2010 at 7:26 am | Permalink

      I don’t think so, which raises the question of why they’re there.

      • Posted July 31, 2010 at 8:40 am | Permalink

        I read somewhere that, because its tail is too short for the purpose, a lynx indicates its mood with its ear tufts.

    • Hempenstein
      Posted July 31, 2010 at 8:43 am | Permalink

      They kinda look like antennae. I wonder if there’s any possibility that they might in some way actually help pick up vibrations indicating incoming prey?

      • Hempenstein
        Posted July 31, 2010 at 8:49 am | Permalink

        Hmm, this one suggests their ears serve no function:

        • Jonn Mero
          Posted July 31, 2010 at 8:56 am | Permalink

          Or that lynxes, like real ladies, don’t appreciate being whistled at, or that some inconsiderate non-prey are making a racket?

      • Posted July 31, 2010 at 8:51 am | Permalink

        That’s possible but unlikely, because the hairs of the tuft are apparently not connected to any specialized sensory cells.

  4. Posted July 31, 2010 at 7:08 am | Permalink

    Wonderful photography and commentary. I have twice seen a lynx here in northern Vermont within the past year or so. Saw another bounding across the Rt. 73 in the Vermont National Forest two summers ago. Like the moose, they’re less rare hereabouts than they once were. The feet, long hind legs, and ear tufts are good indicators.

  5. Bill
    Posted July 31, 2010 at 8:30 am | Permalink

    Good grief! is that a ‘tame’ lynx or one that wandered into a house? I’ve seen ‘tame’ caracals in South Africa – beautiful but tetchy and with a prediliction for pissing on sleeping bags – even if they are occupied.

    • Hempenstein
      Posted July 31, 2010 at 8:55 am | Permalink

      That one may well be the model for Bucky Katt in Get Fuzzy. “You bring me some crap in a metal bowl?? I want a RABBIT!!!”

    • Tulse
      Posted July 31, 2010 at 10:59 am | Permalink

      I would think keeping a 30-lb “pet” with that kind of attitude would be very risky.

    • Posted August 1, 2010 at 9:16 am | Permalink

      I met someone with a pet bobcat once while walking on the Oregon coast. It was pretty tame and would let strangers pet it. The owner said it got really aggressive around other animals, though.

      It was declawed, which IMO is rather cruel for any cat — but in this case, it was probably necessary to protect its humans from serious injury. But then, it’s probably better not to keep exotic animals as pets unless one is geared up to care for them properly.

  6. Posted July 31, 2010 at 8:41 am | Permalink

    I’ve seen exactly one US bobcat in the wild, while hunting as a teenager. I never realised that they were considered the same species as the Canadian lynx.

    • Posted July 31, 2010 at 8:54 am | Permalink

      They aren’t considered the same species any longer.

      “There are four species in the genus Lynx, two of which (the Canada lynx, L. canadensis, and the bobcat, L. rufus) occur in North America. The bobcat—once lumped with the Canada lynx in a single species—is far more common in the U.S.” [from above]

      • Jonn Mero
        Posted July 31, 2010 at 9:00 am | Permalink

        Hm. Didn’t realise that our lynx (Lynx lynx) is bigger and weighs a fair bit more than their North American rellies.

      • Posted July 31, 2010 at 9:05 am | Permalink

        Sorry, I should have said “at one time were considered the same species”. I had always thought of them as different species.

  7. Posted July 31, 2010 at 12:56 pm | Permalink

    My online popgen simulator (for classrooms) is called Red Lynx because I completed the first version while doing field work on NC bobcats (Lynx rufus).

  8. Posted July 31, 2010 at 6:49 pm | Permalink

    As much as I am a fan of Caturday postings, I have to point out that the first/single image of the lynx and the Marty Stouffer Wild America YouTube video are very likely examples of not only nature fakery, but also animal cruelty and slavery of the worst degree.
    For the paid purpose of getting these images, wild animals are captured and kept in circus conditions; let out only for the photo shoots.

    http://www.audubonmagazine.org/incite/incite1003.html

    Publications like Audubon and Nat. Geographic have become increasingly aware of this and now have policy in place to check on the authenticity of art to not only not reward photographers, but also eliminate these practices. No so much some other publishers of nature images and textbooks.

    • Torbjörn Larsson, OM
      Posted July 31, 2010 at 8:03 pm | Permalink

      While I applaud your empathy, I note that not all share it.

      In most species, and still in humans, morality applies preferentially on own species (or family). That you describe is not slavery, either morally or legally; it is at most husbandry.

      Further, if it helps biology, empathy and species preservation, it may be good ROI. (Again, in absence of universal morality, ROI is our usual guide.)

      Finally, we lack references to cruelty. I only browsed the long reference and couldn’t see any statistics or even anecdote on that.

      • Diane G.
        Posted July 31, 2010 at 9:47 pm | Permalink

        Yet another gray area for me. I certainly agree that some captivity is necessary for biological, etc., advances in understanding; and that not all instances of captivity are necessarily cruel or akin to slavery. I don’t agree that all of the incentives to photographers/videographers for getting good footage are morally worthwhile. Wonder how many hares it took to get that first vid (which I, too, thought was obviously staged)?

        • Torbjörn Larsson, OM
          Posted July 31, 2010 at 10:43 pm | Permalink

          Agreed, gray area. I empath with cats, and hares too.

          I’m merely human. (>_<)

  9. Anne H
    Posted August 1, 2010 at 12:53 am | Permalink

    I’ve been fortunate enough to see lynx and bobcats at Maine Wildlife Park.
    http://www.state.me.us/ifw/education/wildlifepark/index.htm
    “Many of the animals at the Maine Wildlife Park were brought here because they were injured or orphaned, or because they were human dependent – raised, sometimes illegally, in captivity. The Park serves as a permanent home for wildlife that cannot survive in the Wild. All kinds of animals are here for their protection and healing. And they’re here for you to enjoy and learn more about.”


2 Trackbacks/Pingbacks

  1. […] Posted on July 31, 2010 by Michael Hawkins I was reading about the Canada lynx on Why Evolution is True and that got me thinking about all the weird pets people […]

  2. […] If you follow the trail far back enough into time you hit the name John Carter.  Remember him?  Ring any bells?  In 1996 he championed the Ban Clearcutting Referendum, and in 2000 the ‘Forest for the Future’ campaign.  What does this have to do with anything?  He scared the paper companies for one. The vote was close, after all who thinks images of clearcuts are pretty and picturesque?  So, in reaction to the upcoming vote the paper companies did some clearcutting…lots of it.  Now it’s been a while since I studied Forestry and Park Management in college but my belief is that in the 11-13 years it’s been since that happened, the opportunistic aspen, birch, and maple that have sprung up are now large enough to create rabbit habitat in all these old clearcuts.hence a large enough population of rabbits enough to support the addition of Lynx.  In researching this I came across an interesting blog post here […]

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