Monthly Archives: October 2018

Denali Diaries Part II: The Wildlife

While Denali is worth visiting on the basis of its scenery alone, it’s the wildlife that will truly shape your experience.  In the summer, Denali is host to some eight species of medium to large sized mammals, including foxes, lynx, wolves, grizzly bears, black bears, caribou, Dall sheep and moose.  Among those, the moose, grizzly bear, caribou, wolf, and Dall sheep make up what’s known as the “Denali Big 5.”

Seeing wildlife in Denali is mostly about luck and timing, but the longer you’re in the park the more chances you have to view wildlife.  As I described in my earlier post, I scheduled and bus hopped my trips in such a way that I stayed in the park most of the day.  This is particularly important for moose, which are generally crepuscular, meaning they are more active in the morning and evening . Everything else is really just a gamble. Sometimes the odds are in your favor and sometimes they’re not. For what it’s worth, though, out of my four all-day trips into the park I got The Big 5 twice, both during the times I stayed primarily on the bus.

While I always left the park having experienced something new, there were definitely trips that were more memorable than others, and the range of experiences really made me appreciate the luxury of being able to go multiple times.  Whatever wildlife you do have the privilege of encountering is sure to fan the flames of your love affair with this park, but I imagine for many people that affair starts first and foremost with the most visible and charismatic of Denali’s wildlife: The grizzly bears.

DSC_0877

I took this photo in late August, just as the colors started to change.

By late July, bears across Alaska are gearing up for hibernation by entering a phase called hyperphagia, where they basically eat constantly and gain somewhere on the order of 400 pounds.  In the park, their diet consists mostly of blueberries, soapberries, and roots, but they will gladly eat whatever mammals they can catch, including small rodents, caribou, moose and even other bears.

A big highlight when bear watching is seeing sows out with spring cubs. Unlike mom, the young are generally a lot darker in color, prompting people to sometimes mistake them as black bears.  Observing cubs playing, foraging, and trying to keep up with mom is definitely the kind of experience that will make you wonder if you were somehow transported, Truman style, to some kind of nature documentary, but in the best kind of way.

DSC_0899-2

While I won’t pretend for a second that seeing bears ever gets old, they honestly weren’t the animal that I was most looking forward to encountering when I arrived in Denali.  Maybe it’s because I’d never seen one before, or because of some deep affection instilled by decades of Christmas marketing, but something about caribou utterly charms me.

DSC_0211

Unlike many of Alaska’s other herds, the Denali caribou do not undertake an immense seasonal migration, opting instead to remain almost exclusively within the bounds of the park year round. Unless you can travel into the interior of the park, however, you’ll have little luck seeing them in the winter.

DSC_0590

Denali used to play host to a herd that ranged in the tens of thousands, but after decades of over hunting followed by a mysterious period of low calf survival and harsh winters, Denali’s herd has dwindled to around 2,000 individuals.  Fortunately, things seem to have stabilized for the time being. I wish I had seen more before the end of the season, but I’ll never forget what it was like watching this small herd move through this painted hillside.

DSC_0591

The ungulates that seemed to most delight my fellow visitors, however, were the moose.  For all of Denali’s hooved animals fall is the rut, which means males have grown out their antlers or horns and are putting them to use in sparring (practice) matches, as they ready themselves for the violent matches to come.  I only saw such behavior between moose once.  They locked antlers for a few seconds and went back to grazing shortly thereafter.  Unfortunately it was too far away to bother with any photos.  I’ll admit, seeing a bull moose, particularly on foot, is a gripping experience.  However big you imagine them to be, they’re bigger in person.  The rack alone can be 40lbs.

DSC_0298

In Denali, the stakes of these fights are high, as the moose here operate in a polygynous system, where the victor will mate with and defend an entire heard of females.  In other places, moose form monogamous pairs for the breeding season.

DSC_0308

It was early morning still when we watched this cow move her two calves across the valley. They seemed pretty wary of our bus, though her biggest real threat is the park’s main carnivorous predator: The gray wolf.

DSC_0408

Even in Yellowstone I don’t get my hopes up about seeing wolves despite there being far more individuals there. Across the Denali’s 6 million acres, there are only 30 known packs comprising about 75 adults. You can imagine my delight then, when, as we were making our way out of the park at dusk on our first trip, we rounded a corner to see this rump trotting up ahead of us. As it happens, I had been walking the road on foot only minutes before. I probably wouldn’t have caught up with it had I not gotten on the bus, but it’s still pretty incredible to imagine that I more or less went hiking with a wolf. We must have followed this adult for about a mile. It stopped a few times, evening giving it’s signature mournful howl a before it disappeared off the side of the road. Honestly, that would have been enough for me, but our second to last trip had something really special in store.

DSC_0054

I had heard whispering about wolf pups back at our housing campus but I never thought much of it. I figured that was deep interior kind of stuff, the kind of trek our field schedule just wouldn’t permit. So while I figured it was something exciting when we arrived at a jam packed road, I just wasn’t picturing this…

Cue total F-ing meltdown on my part.

This pup was born sometime mid-may to the single male and female that comprise the Riley Creek West pack.  By around four months the pups start venturing away from their den site.  Lucky for us, for a few day stretch the area they were exploring was right near the road by Toklat.  After a few days, they moved away from the road, which was no doubt for the best.

The last animal I have the great pleasure to highlight is the most iconic of Denali’s wildlife.  In fact, it was this animal for whom the park was dedicated.  The endemic Dall sheep.

DSC_0579

In 1906, hunter and conservationist Charles Sheldon noticed a worrying decline in the Dall sheep favored by hunters.  He feared that without protection, they would be hunted to extinction. Now this is an all too familiar concept, but coming off the heels of the “era of abundance” this was actually a revolutionary way of thinking in western culture.  Until 1900, colonists/settlers in the United Stated hunted without regulation and, seemingly, without much thought or worry as to the integrity of ecosystems. As a frame of reference, the field of wildlife management wouldn’t come onto the scene for another two decades.

Sheldon, however, had the foresight to recognize that something must be done and set out to establish Denali as a national park.  It took 11 years, but in 1917 Woodrow Wilson signed the bill into law. Since that time Dall sheep populations rebounded and are currently considered healthy.

Despite their robust numbers, however, most of my experiences of seeing Dall sheep in the park were “technical”.  As in, “technically those white specks on the mountain side are Dall sheep”. So on our last day as we traveled out of the park, I couldn’t believe my eyes when a ewe and her lamb were jogging down a hillside close enough that you could judge their forms as Dall sheep even with your naked eye. For the minute or so that we were able to watch them, I felt myself overcome with equal parts joy and despair.  I was profoundly grateful for the gift of such beauty and yet so sad that once again its integrity is under such threat.

DSC_0587

Driving home one night, my fellow passengers and I shared our backgrounds and motivations for visiting the park.  Some came to experience mammals the size of which dwarfs anything in their native country, some were fulfilling missions to visit all the National Parks, while others had arrived with a spirit of adventure and little else.  Together, we marveled at the unforgettable things we had seen and shared our anxieties that future generations may not be so lucky.  We discussed our anger and disappointment (or among some of the foreign tourists utter bafflement) at the US government’s unwillingness to act more effectively on climate change.

One hundred years ago someone looked at this land, recognized that change must be implemented, and fought for over a decade to convince congress that in fact wild spaces and wildlife mattered enough to act.  As a result, my fellow passengers and I got to see and experience things that will bring us joy the rest of our lives.  The question now is whether we will wage our own fight for the future, or if we will watch from the sidelines as it turns to ash in our warming world.

***

DSC_0632

For information about climate change in the arctic please visit the following resources

NASA’s Arctic-Boreal Vulnerability Experiment

The National Snow and Ice Data Center

Chasing Ice

And remember…
~PLEASE VOTE ON NOV 6TH~

 

 

9 Comments

Filed under Climate change, Conservation, Denali Diaries, Ecosystem, Photography, Wildlife

You need to know more about jay spit

Look, I’m a reasonable person.  I know what you’re thinking.

“Literally never has it occurred to me I might know too little about jay spit.”

But here’s the thing: it’s actually super interesting and you really can’t understand Canada jays without knowing about their saliva.  It would be like trying to understand the internet without cat videos-you just can’t do it.  So trust me when I tell you this is the information you didn’t know you needed.

DSC_0164

In the early 1960’s Walter Brock was examining Canada jay corpses when he discovered that they have massive salivary glands on par with the ones found in woodpeckers.1 Such generously sized glands are found in no other songbird.  Furthermore, like the woodpeckers, it’s not just that Canada jays make a lot of saliva, but they make a lot of sticky saliva.  At the time this discovery was made, it was already known that the enlarged glands of woodpeckers served to allow for a foraging tactic called “tongue probing” where, like anteaters, the birds use their long sticky tongues to extract food from narrow crevices.  Although Canada jays don’t have especially long tongues, the ability to tongue probe seemed the most parsimonious explanation for this strange adaptation, and Brock suggested that this strategy may actually be the key to the jays’ winter survival.  A study a few years later examining their foraging behavior revealed that they don’t feed in this manner, however.  They feed more or less the same way the other corvids do.2  It seems instead, that it’s what they do with the food after that’s different.

DSC_0440

Rather than using their copious amounts of weird, sticky spit for acquiring food, it’s used for depositing it.  If you watch a jay closely after it’s got a bit of food you’ll notice it seems to have missed Emily Post’s memo about chewing with your mouth closed. Over the course of a few seconds you’ll see the food peek out from the bill as the bird moves it around inside its mouth.

DSC_0366

This jay picked up this bit of food about 60sec before this photo was taken.  Now it’s working it around with its tongue, coating it in sticky saliva.

Once sufficiently spit coated, the bird will deposit the food blob (called a bolus) onto the foliage or trunk of a tree.  No matter the material or angle, once the spit dries the food is safely secured come hell or high-water.  Because these caches are pretty small there’s little fear that many will be found.  More importantly, by stashing food high in the trees instead of burying them into the ground like many other cache-dependent corvids do, Canada jays can thrive in areas that receive much heavier snowfall, allowing them the title of the most northern residing jay in North America.

Here’s where it all really comes together though.  If you’ve seen me write about Canada jays before you’ll have noticed that it’s almost inevitable that I’ll use the phrase “Cute little faces” at some point to describe them.  But have you ever wondered why? Why do they have such cute little faces?  While jays do feed more or less in the same way as other corvids the one exception is that they don’t hammer at objects.  If you’re ever given a crow or a Steller’s an unshelled peanut you’ll know exactly the motion I mean. Without the need the hammer objects, or dig holes for burying food, Canada jays don’t need the heavy bills their cousins do.2  Instead they have the blunt little bill that helps give them their characteristic baby-faced look.  So not only is their spit responsible for their ability to tough it out in some of the harshest winter environments this continent offers, but it also means they get to look super cute while doing it.

So like I said, you don’t really know Canada jays until you know a thing or two about their spit.

DSC_1042

Literature cited

  1.  Brock WJ. (1961). Salivary glands in the gray jay (Perisoreus). The Auk 78: 355-365
  2. Dow DD. (1965). The role of saliva i food storage by the gray jay.  The Auk 82: 139-154

13 Comments

Filed under Birding, Canada jays, Corvid trivia, Diet, Field work, Jay behavior, Science

Denali field notes: A hare of another color

Up until the last few weeks, spotting snowshoe hares before they darted out from the adjacent vegetation was something I considered myself fairly lucky to do.  After all, it’s literally a matter of life and death for them to remain as undetected as possible.  As September came to a close, however, I found myself spotting them more often and from further away than I had previously, and not just from weeks of practice.  Their concealment was being betrayed by the very mechanisms designed to keep them safe.

DSC_1168.jpg

There aren’t a lot of animals that call Denali home all year long, but those that do need effective strategies for staying alive during the essentially 8 months long winter.  For Denali’s snowshoe hares, one of these strategies is to adapt in an entirely new winter outfit, something only 20 other animals in the northern hemisphere do.1 While in the summer they are a mottled reddish brown, starting around late September the hares grow in their nearly all white coats. The ears are typically the first to change, with the rest of the body following suit shortly thereafter.

This transformation is mediated by changes in the photoperiod that affect melanin production.  Although the full explanation is quite complex, the core mechanism is that the shorter day length increases the hormone melatonin, which suppress the melanin producing hormone prolactin.1

While this strategy is good one for long winters blanketed in snow, changes in snow regimes are making this transition more precarious.  Camouflage mismatch–which is generally considered when more than 60% of the coat is different from the surrounding environment–can result either from winter coats that have come in too early, before the snow arrives, or because the snow pack lingers inconsistently.  This year, the lower elevations of the park have yet to see so much as a flake of snow, though you wouldn’t know that by looking at the hares.  As I have already experienced, such mismatch makes hares considerably easier to detect, a big problem for basically everyone’s favorite winter meal.2

DSCN1302

Although hares can adjust the timing of their molts to a small extent, it’s won’t be enough to keep them in sync with the more dramatic shifts climate change has in store for the future.  This is especially problematic because hares don’t seem to be very aware of their mismatch and attempt to compensate behaviorally by say, hiding behind vegetation or choosing resting spots that more closely match their color.3 Other animals, particularly birds, seem better at this.  Rock ptarmigan for example will actually dirty themselves to more closely match patchy snow.4

DSC_1160

Given the immense selection pressure on these animals to match their environment and the high variation in the traits responsible for such color changes, it’s possible that hares will be able to keep pace with an already changing arctic landscape, but we don’t know for sure.  The alternative will be to add hares to the growing list of once common animals that now require invasive management strategies to stay afloat in the anthroproscene.

 

Literature cited

1. Zimova M, Hackländer K, Good JM, Melo-Ferreira J, Alves PC, Mills SL. (2018). Function and underlying mechanisms of seasonal colour moulting in mammals and birds: what keeps them changing in a warming world? Biol. Rev. 93: 1478 – 1498.1478 doi: 10.1111/brv.12405

2. Pedersen S, Odden M, Pedersen HC. (2017). Climate change induced molting mismatch? Mountain hare abundance reduced by duration of snow cover and predator abundance. Ecosphere 8: 01722

3. Zimova M, Mills SL, Lukacs PM, Mitchell MS. (2014). Snowshoe hares display limited phenotypic plasticity to mismatch in seasonal camouflage. Proc. R. Soc. B DOI:

4. Montgomerie R, Lyon B, Holder K. (2001) Dirty ptarmigan: behavioral modification of conspicuous male plumage, Behavioral Ecology 12: 429–438.

5 Comments

Filed under Uncategorized