Explore Fall in Grand Teton and Yellowstone National Parks!

Fall along the Moose-Wilson Road of Grand Teton National Park

There is a crispness in the air today Jackson Hole.  Mornings are cold and leaves are starting to change.  It begins with fireweed flowers and smaller shrubs, before peaking with aspens and cottonwoods, our two major deciduous trees species.  The fall has always been a special time to me, with fond memories of still evenings listening for the bugling of elk beneath golden aspen groves.  Right now there is something for everyone in Grand Teton and Yellowstone National Parks, from rutting elk to active black and grizzly bears preparing for hibernation.  


Fall Foliage

Are you a leaf peeper?  If you like gazing at and photographing fall foliage you just might be!  It’s an informal name for folks who travel to observe the changing of fall colors.  Here in Jackson Hole, fall colors astound, beginning first at higher elevations and then coursing downstream, following cottonwood groves along the Snake River.  Grand Teton National Park has countless photography locations to capture the sights.

What is happening in fall anyway?  Plants contain a green colored pigment called chlorophyll which is responsible for photosynthesis, the process which converts sunlight to sugars.  As days shorten plant leaves slow down the production of chlorophyll which allows other pigments, called carotenoids, to become visible.  The stunning reds, oranges, and yellows we see in fall have been present all along!  Read more about the Science of Fall Foliage Here!

Fall at Oxbow Bend

Fall at Oxbow Bend, Grand Teton National Park

Deciduous plants drop their leaves to save energy in winter when they would be otherwise unable to photosynthesize due to freezing temperatures.  With out liquid water the chemical reaction cannot occur.  In stark contrast to aspens and cottonwoods, our pine, spruce, and fir trees are known as evergreens, appearing to never lose leaves.  (they are constantly dropping needles, just not all at once!)   Evergreens produce sturdy needles which can resist winters chill, this allows them to begin photosynthesis as soon as water is once again available in the spring.  Two unique strategies for surviving in the Greater Yellowstone Ecosystem.


Sparring Bull Elk, the Rut!

When aspen leaves begin to yellow, it is a sure sign the rut has, or is about to start.  Sit quietly beneath one of these trees at dawn and you may hear an eerie sound echo across the forest.  It’s a bugle, a loud scream large bull elk make to proclaim their dominance for mating rights.  One of North America’s most spectacular wildlife behaviors, bull elk will call back and forth, issuing challenges.  If you are lucky the next bugle you hear may be close enough to see the performers meet.  They will stand tall, broadside to each other.  Breathing heavily, water vapor will form in the frosty air.  If one does not retreat the two will bow antlers and then lock them together, wrestling back and forth until one gives up and flees.  The victor may often attempt to gore the loser while in pursuit. 

Bull elk in rut, Grand Teton National Park

A bull elk bugles during the Fall Rut, Grand Teton National Park

All of our ungulates, or hoofed mammals, mate in fall so that their offspring will be born in spring.  And elk aren’t the only ones to aggressively establish dominance; moose, deer, pronghorn, and bison will also be in rut this fall, a unique spectacle to experience beneath the shadow of the Tetons.

 Rutting Bull Moose observed on a wildlife tour of Grand Teton National Park.

Rutting Bull Moose observed on a wildlife tour of Grand Teton National Park.

Preparing for Hibernation

Animals use three primary strategies to survive in the Greater Yellowstone Ecosystem, Adapt, Migrate, or Hibernate.  One of our most popular animals to see, bears, are experts at the third.  Throughout the summer bears build up fat reserves, preparing for winter.  As omnivores, they will eat just about everything, grasses, roots, berries, elk calves, carrion, ants, and even moths roosting in high elevation boulder fields!  Towards the end of summer foraging picks up, entering a stage called Hyperphagia or over eating.  Foraging constantly, bears will eat upwards of 20,000 calories a day!  Right now in Grand Teton National Park much of this calorie budget is coming from the berries of the hawthorn, a thorny bush often found near water.  

A grizzly sow and cubs feed on service berries in Grand Teton National Park.

A Grizzly Sow and Cubs feed on serviceberry during a recent Grand Teton Wildlife Safari.


Transitioning to Winter

Fall is a transitional time, with our over 1000 plant species shutting down photosynthesis, in preparation for the long winter.  Many drop their colored leaves or die back to the ground where insulated snow cover protects the living roots.  Our rutting mammals complete the mating season and begin migrations out of high elevations to more protected valley floors,  often concentrating in huge numbers such as elk on the National Elk Refuge.  As two thirds of our bird species leave the valley for warmer climates and bears disappear to hibernate, we welcome new arrivals to winter in Jackson Hole.  Raptors like the Rough Legged Hawk will soon arrive from the Arctic Circle, and mighty bighorn sheep will return from the rugged Gros Ventre Mountains, beginning their late fall rut just outside the town of Jackson.  

Bighorn Sheep Butt Heads on the National Elk Refuge near Jackson, WY.

Bighorn Sheep Butt Heads in early December on the National Elk Refuge near Jackson, WY.

Rough Legged Hawks Migrate through the Jackson Hole Valley in Winter from the Arctic Circle!

Rough Legged Hawks Migrate through the Jackson Hole Valley in Winter from the Arctic Circle!

The magic of fall in the west is something I was introduced to as a young child growing up near Rocky Mountain National Park.  Let the experienced guides at Jackson Hole Ecotour Adventures share this story when you visit Grand Teton and Yellowstone National Parks this fall.  Join us on a half day, full day, or multi day trip through fall (check out this multi day trip report!) in the Greater Yellowstone Ecosystem, it’s one you wont soon forget.  Trips from now until October 15th are 10% off using the code ETAFALL2017!  Visit our website and click the Book Now! Button or give us a call at (307) 690-9533 to book.  We hope to see you soon!

Guide Josh Metten has spent his entire life exploring and living in the Rocky Mountains of Colorado and Wyoming. He is an Ecotour Adventures Naturalist, photographer, conservationist, and outdoor enthusiast. Josh lives in Jackson, WY.

A bull elk herds a group of cows during the rut, or mating season in the Jackson Hole Valley, Grand Teton National Park


It’s Autumn in Grand Teton and Yellowstone National Parks.  Now is the time to experience one of North Americas most spectacular wildlife displays.

Arrive early, before dawn lights up the mountains.  Open meadows near forested areas are ideal.  Listen.  From the still morning air a loud bugle may echo through the forest.  It’s a master bull elk, calling to his harem of female, or cow elk.  He’s also challenging other males.  This is elk mating season, also known as rut, and the scenery of golden aspen trees beneath jagged peaks provide the perfect backdrop. 

A Bull elk bugles in Grand Teton National Park during a Grand Teton Wildlife Safari.


What is the Rut

With our long harsh winters, animals in the Greater Yellowstone Ecosystem must time reproduction exactly to make the most of the summer bounty.  Large herbivores like elk, deer, moose, bison, pronghorn antelope and bighorn sheep all mate in fall, during the rut.  Starting in August, antlers, concealed beneath fuzzy velvet begin to harden.  Blood supply to the developing bone gradually cuts off and by September elk have begun rubbing off the velvet.  Young conifer trees can be stripped of branches and bark from top to bottom due to this behavior which stains the antlers dark brown. 

Now polished smooth, dominant bull elk begin locating herds of females, bugling to attract them.  Females are both attracted to and fearful of bull elk.  Throughout the year bulls act very aggressive, even chasing females away from desirable forage.  However, during the rut, as cows are approaching estrus, the attraction towards bull elk ends up overpowering any apprehension they may have.  Bull elk also attract females through scent marking.  They thrash young aspen trees while urinating, spreading their scent in the process. 

The biggest bulls do most of the mating, their antler size a direct result of how well they foraged during the summer months.  Energy expenditures from growing antlers as well as the rut are massive, and dominant bulls rarely maintain their status for more than a few years.  Paradoxically, bulls are far more likely to die in winter due to losing up to 10% of their body weight during the rut!  Wolf predation is one factor and scientists with Grand Teton National Park have found bull elk comprise the majority of animals killed in winter.

Due to the high energy expenditure required, master bulls rarely maintain their dominance over other bulls for many years. Photo Taylor Phillips


Winter Survival

When the rut is completed and snow begins piling up elk begin spectacular migrations, descending into valleys where snow cover is manageable.  At 8,000 feet, the Yellowstone Plateau, is no place for an elk in winter.  Exiting the park in all directions, some end up close to 80 miles south of Yellowstone, in the National Elk Refuge.  In one of the largest gatherings of elk in the world, upwards of 9,000 will winter here, just steps from downtown Jackson, WY. 

Elk have always used low elevation valleys like Jackson Hole in winter, but in the late 1800’s encountered a new competitor for food.  Homesteaders brought cattle to the valley, occupying valuable winter range.  The Jackson Hole Herd began starving  in large numbers, alarming conservationists like Stephen Leek.  Leek photographed the plight of elk in the valley, leading to the establishment of the Elk Refuge in 1912.  With a winter range now set aside from livestock, elk have a place to spend the winter.  Refuge staff continue to provide supplemental feed, a practice started to keep elk off of private property.  Elk aren’t the only ones on the refuge in winter however.  They are joined by hundreds of bison, bighorn sheep, a small herd of pronghorn antelope, eagles, hawks, coyotes and even wolves. 

A cow and calf elk follow receeding snows out of the National Elk Refuge to Grand Teton National Park. Photo: Taylor Phillips


Spring Reproduction

In spring, when melting snow awakens plants dormant from winter, elk begin following this greening up of the landscape, reversing the great migrations of fall.  Wary of predators, female herds choose sheltered terrain over habitat with good forage, to better increase the chances of their calves surviving.  Since the cows all mated at approximately the same time, calves are born in a flush of life.  With wobbly legs they spend much of their first few weeks of life bedded down, hoping to avoid predators.  As they grow, calves become more active and will excitedly jump and run around herds of adult cows throughout the summer.  Fall bugling is not the only sound elk make, and herds are often quite audible as the cows and calves call back and forth to each other. 

We observed this spotted elk calf playing with its food on full day tour of Yellowstone National Park. 


Into Summer

During this time, adult bulls have moved a different direction, seeking out high quality forage to start regrowing antlers for the next rut.  Their previous ones are now lying on the forest floor.  If discovered outside of the National Parks after April 30th, they may be harvested by those who are willing to look.  Left on the ground, small mammals and even elk themselves will chew on the ends obtaining valuable calcium. 

Compare the velvet covered antlers of this spike bull to the adult bull in the background.  He has stripped off velvet and is pursuing female herds as part of the fall rut.


Antler growth peaks in early summer, as the flush of high nutrient vegetation is abundant.   At nearly an inch per day they are the fastest growing bones in the animal kingdom.  Male elk first grow antlers during their second summer.  Called 'spikes' due to the lack of forks in the antlers, these young bulls will remain with their mothers until being chased off by aggressive males in fall.  In just a few years they to may be big enough to challenge other bulls with a bugle that pierces the stillness of cold mornings in the Greater Yellowstone Ecosystem.

Now is your chance to experience this amazing spectacle in Grand Teton and Yellowstone National Parks!  From now until October 15th Wildlife Safaris are 10% off when you use the code ETAFALL2017 while booking!  To join a safari with Jackson Hole Ecotour Adventures visit our website and click the Book Now! Button or give us a call at (307) 690-9533.  We hope to see you soon!

Josh Metten has spent his entire life exploring and living in the Rocky Mountains of Colorado and Wyoming. He is an Ecotour Adventures naturalist, photographer, conservationist, and outdoor enthusiast. Josh lives in Jackson, WY.

Golden aspen trees light up the landscape at Oxbow Bend in Grand Teton National Park.

Fall is coming to Jackson Hole.  Aspen groves in northern Grand Teton National Park are already beginning their seasonal color change.  Soon a ribbon of bright orange, yellow, and even red will flow down the cottonwood forests of the Snake River as the trees prepare for their winter slumber.

The annual progression of fall colors marks the end of a seasonal growth cycle of our deciduous (plants which shed all of their leaves at the same time) trees and shrubs.  Leaf peepers are flocking to Jackson Hole to observe this seasonal spectacle as well as enjoy our abundant wildlife.  It's one of our favorite times of year to explore Grand Teton and Yellowstone National Parks.  Want to learn more about the science of changing leaf color?  Read on.

Horses beneath the Teton Range in Fall.

Our favorite view of the wild west.  Horses grazing beneath the Tetons in northern Jackson Hole

Right now, shorter days and longer nights are beginning to have a profound impact on plants.  At the base of each leaf, cells are rapidly dividing, forming a layer of loose cells known as the Abscission Layer. 

Throughout the summer this junction was a transportation superhighway.  The roots sent minerals and water up to the leaf, key components in the manufacture and use of the green pigment chlorophyll.  Along with several other pigments we will talk about in a moment, chlorophyll harnessed the energy of the sun to photosynthesize, creating carbohydrates, which were in turn shipped down to the roots to fuel later growth.


Here Come the Colors!

As longer nights continue to increase cell division in the abscission layer, we are already seeing chlorophyll production slow on wildlife safaris of Grand Teton and Yellowstone National Parks.  As the green color of chlorophyll disappears, other pigments, formerly hidden, are beginning to appear. 


The beautiful golden yellow color we see in the cottonwoods along the Snake River, and the aspen groves of the Teton Mountain Range are caused by pigments known as Xanthophylls.  These pigments, like chlorophyll, also harvest energy from the sun, but are also found in egg yolks and even human blood plasma!

Fall sunrise at Schwabacher Landing, Grand Teton National Park.

Beaver dams in a side channel of the Snake River at Schwabacher Landing act as spectacular reflecting pools, especially as the cottonwood trees turn yellow.


Carotenoids also work with the yellow Xanthophylls and green Chlorophylls to harvest light energy throughout the summer.  Look for them on aspen and cottonwood trees, as well as willows and other smaller shrubs growing in Jackson Hole.

Cow Moose, Grand Teton National Park

A cow moose strips the orange carotenoid laden leaves off of a bush in Grand Teton National Park.

Red and Purple

Red and purple pigments, known as Anthocyanins, are less common than yellow and orange but will also make an appearance in the fall.  Remember the abscission layer?  As it cuts off the movement of molecules, sugars become trapped in the leaf, much of which becomes the pigment anthocyanin.  East coast maple trees are particularly prized for their red colors in fall but we have numerous shrubs which will turn red including the much smaller Rocky Mountain Maple.  Look for it near water, especially in the Snake River Canyon south of Jackson Hole.

Hawthorn Trees along the Moose-Wilson Road, Grand Teton National Park

Hawthorn Trees along the Moose-Wilson Road turn red from Anthocyanins.  Hawthorns also produce an edible berry favored by both black and grizzly bears!

As autumn progresses, the cells in the abscission layer become more dry and “corky”.  Connections between cells weaken and the leaves eventually break off, blanketing the ground with color.  This carpet of yellow, orange, and red won’t last long however, as light and freezing temperatures cause the pigments to break down.  A final group of pigments emerges, the tannins.

Throughout the life of a leaf, tannins aid it in resisting decay and become visible only after other pigments have degraded.  Elk and other hooved mammals may dig up these leaves from beneath the snow in winter, or they will gradually decompose back into the soil completing the life cycle.  


Factors influencing the quality of fall foliage

Though the start of our fall foliage season is relatively fixed to day length, temperature, sunlight, and soil moisture all greatly influence the quality of fall foliage display.  Want more anthocyanins (Reds and Purples)?  Hope for abundant sunshine, which speeds up the decay of green chlorophyll, combined with cool temperatures.  However, if the temperature drops too much, to below freezing, the creation of red and purple colors will also be impeded.

Worst of all is an early frost, which can prematurely end the foliage season.

Finally, drought conditions during the growing season can cause the abscission layer to form early, leading to leaves dropping before development of fall coloration!  Fortunately our wet winter has precluded major drought in the Greater Yellowstone Ecosystem this year so we are unlikely to have this issue.

One of our favorite aspen groves in Grand Teton National Park displaying all four pigments at once!  


Recipe for a perfect Fall Foliage Season

We are on track for some great leaf peeping this fall and have fingers crossed for dry, sunny, and warm autumn days with cool but frostless nights.  A lack of wind and rain will prolong the displays throughout September and October. 

Regardless of the weather, fall is always one of our favorite times to explore Grand Teton and Yellowstone National Parks.  Bull elk are bugling, bears are bingeing on all the food they can gather, and the great migrations of birds and mammals across the Greater Yellowstone Ecosystem are, or will soon be in motion. 

Listening to the sound of bull elk bugling beneath golden fall foliage is one of our favorite experiences in Grand Teton National Park!

From now until October 15th Wildlife Safaris are 10% off when you book with the code ETAFALL2017!  Find out how you can experience this spectacular time of year with a half day, full day, or multi-day safari with Jackson Hole Ecotour Adventures by visiting our website .  To join a tour click the Book Now! Button or give us a call at (307) 690-9533.  We hope to see you soon!

Photos and blog by Naturalist Josh Metten

Guide Mark Byall also contributed to this post.

1999 Total Solar Eclipse Photo by: Luc Viatour

In less than three weeks a once in a lifetime event will occur across Jackson Hole and Grand Teton National Park, a total Solar Eclipse.  At approximately 10:16am on Monday August 21st, the eclipse will begin, as the moon begins to block the sun’s rays.  In just over an hour, the moon will completely obscure the sun and at around 11:35am Totality will be reached.  For over two minutes the Jackson Hole Valley will be cast into darkness.

The 2017 Eclipse is the first to cross the entire continent since 1918, and will be visible in twelve states, from Oregon to South Carolina.  With stunning mountain vistas, Grand Teton National Park and the valley of Jackson Hole are popular locations for viewing the eclipse, which is predicted to be the valley’s largest event in history.  Planning on viewing the eclipse in Jackson Hole?  Here’s what you need to know.


This map shows the route and line of totality of the 2017 Solar Eclipse. 


Viewing Locations

Eclipse viewers will want to find a location within the path of totality (see above map). Jackson hole is a spectacular viewing area, but, due to the limited road access out of the area could be problematic if weather prevents viewing of the eclipse.  Should this occur, expect gridlock of roads leaving the valley the morning of the eclipse.  For those interested in playing the odds of seeing the eclipse occur over the Tetons in Jackson Hole (they are good, about 78% chance of clear skies), numerous options exist.  

The Jackson Hole Valley and Grand Teton National Park lies directly in the path of the 2017 Total Solar Eclipse are you ready?

Grand Teton National Park expects the eclipse to be the largest event in the history of the Park and has set up 5 different designated viewing areas in prime locations throughout the park; along the road to Kelly, the Gros Ventre Campground, the Craig Thomas Discovery and Visitor Center in Moose, Colter Bay and Jackson Lake Lodge.  Each area will have additional bathroom facilities and staff on hand to help out. The Gros Ventre Road, located in the center of the path of totality, will be a popular viewing area and will be managed for one way traffic heading north.   See the below map for the other viewing areas. 

Grand Teton National Park provided this map which outlines the 5 major eclipse viewing locations in the Park, all of which fall within the path of Totality. 

Parking outside of the designated viewing areas will be restricted to existing pullouts which will fill up very early in the morning and along the shoulder of the Teton Park Road, which runs north from the Craig Thomas Discovery Center at Moose Junction along the base of the Tetons.  To provide access for emergency personnel, no shoulder parking will be allowed along US HWY 26/89/191 or on the Moose/Wilson Road.  Additionally, park fees will be suspended on eclipse day to ease traffic entering the park. 

Great eclipse viewing options exist outside of Grand Teton National Park, right in the town of Jackson and at Teton Village.  Wyoming Stargazing is offering a free public eclipse viewing event at the base of Snow King Mountain.  An eclipse viewing area is available at Teton Village and a limited number of tickets are being sold for those who want to ride the Sweetwater Gondola up Jackson Hole Mountain Resort.

Hiking opens up numerous possibilities for great eclipse viewing locations.  The majority of the Teton Range falls within the path of totality and a hike to any of the summits should provide for great viewing.  The Gros Ventre Mountains east of Jackson Hole, Palisades Wilderness Study Area to the South, and Snow King Mountain, located just south of town will also provide great viewing locations. 

Regardless of location be sure to find a view looking south and east to watch the eclipse.  If you want to see the moon’s shadow racing across the earth at about 1 kilometer per second get a view looking to the west.


Traffic Considerations

With the 2017 Jackson Solar Eclipse expected to be the biggest day in history, traffic will be a major issue, expect significant delays both before and after the eclipse.  Many eclipse viewers will use bicycles and the extensive Pathway System to avoid traffic delays.  Those using vehicles are encouraged to carpool or use the START bus route which will be free on eclipse day. 

Plan on Getting Stuck!  It is likely that roads may become impassable before and after the eclipse so plan accordingly.  Ecotour Adventures trips will be leaving early to arrive at our viewing locations and plan on staying there well after the end of the eclipse.  Bring sufficient food, drink, and emergency supplies for the day and plan on limited or unavailable cellular or internet service due to the increased amount of visitors.  Please protect our public lands by packing out anything you pack in!

Traffic delays caused by bear jams like this one we viewed earlier in the summer may pale in comparison to the 2017 Teton Eclipse.

Once you have arrived at your eclipse location sit back and enjoy the show.  Solar glasses or some other approved solar filter is a must for viewing the eclipse until the exact moment of totality at around 11:35 am, when it will be safe to view without them for around 2 minutes.  We will be handing out free solar glasses on all Grand Teton and Yellowstone Safari Tours the week before the eclipse, find out how to join us here.



Other things to do in Jackson Before and After the Eclipse

The week before and after the 2017 Jackson Eclipse will be full of fun activities both eclipse and non eclipse related.  On Saturday August 19th Wyoming Stargazing is offering a Pre Eclipse Party featuring Nasa Astronaut Scott Altman and Astrobiologist Dr. David Grinspoon. Visit their website for more information.

On Tuesday, August 22nd The Town, County, and Grand Teton National Park are hosting post eclipse cleanups, find out how you can join by emailing volunteer@tetoneclipse.com

Though our trips the day of the 2017 Teton Eclipse are fully booked, August is a great time for wildlife viewing in both Grand Teton and National Parks and EcoTour Adventures will be out leading half, full day and multi day trips of the parks.  Learn more about how to join us here!


Additional Resources:

Science of Eclipses



Header Background Photo: Solar Eclipse by Luc Viatour, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=132886

Photos and blog by Naturalist Josh Metten