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Welcome to Nature News from GYE #6 May 28, 2020

It’s that time of year when it’s sunny and 60 one day and snowing the next day!  Many of my 40+ years in this region we’ve seen snow on Memorial Day and 4th of July and this year was no exception.  It snowed much of Memorial Day weekend.  Weather in the mountains is erratic and the results are dramatic. In Yellowstone Park sits a huge body of water, Yellowstone Lake.

The lake has 140 miles of shoreline at about 7700 feet in elevation, and an average depth of 130 feet (and over 400 feet deep in some parts of the lake). Notice the hot springs on the Shore of Yellowstone Lake.  This is just one example of the volcanic history of the lake.yellowstone lake in winter w west thumb

The surface of the lake freezes by Christmas each year, despite hot vents arising deep from the bottom.  Anticipated each spring is timing of “ice out” (the ice coming off the lake.)  This year it was May 21.  At the same time, snow levels are dropping, more open ground is greening and life is emerging.  Visible are young bison, elk, bear cubs, wolf and coyote pups .  Some nesting birds like the Common Loon, White Pelicans and Osprey are just arriving.Pelican feeding young - Copy


Also at this time, fisheries biologists are putting boats in the water to manage a non-native fish to these waters, Lake Trout.  These trout are native to the Great Lakes, Alaska and Canada, and even in some parts of Montana.  And yes, they are fun to catch and eat, but they don’t belong in Yellowstone Lake.   They were first documented in Yellowstone Lake in the mid-90s and it was recognized they had been illegally introduced.  These large, deep-living trout prey on the more shallow dwelling, native cutthroat trout.  They also compete with the Cutthroat for some of the food sources traditionally eaten by “Cuts” creating a “double edge sword” that has impacted Cutthroat trout populations, which became perilously low.

These native populations are pivotal as they keep the circle of life turning.  Species like cuthroat trout - CopyCutthroat trout that impact the lives of many others, are called Keystone Species.  As their numbers drop, other species have to adapt or disappear.  Examples include River otters, Grizzly bears, Mink, Common Loon, Osprey and dozens of other species that have depended on shallow living Cutthroat trout as a food source.  Lake trout live at great depth and cannot substitute as a food source.     Since the late 1990s almost 3 million Lake trout have been removed from Yellowstone Lake by park suppression methods.  Biologists monitor both species and have seen indications of a decrease in the population of Lake trout and increasing abundance of Cutthroat trout.  It is unlikely Lake trout can ever be completely removed from the lake, but by managing and keeping their numbers low, Cutthroat numbers can continue to rebound and once again, fill that needed niche.

More Grizzly Bear News

Located south of Yellowstone Lake,  Grant Teton National park is the home of a  very “famous” bear who is a “darling of photographers”, Bear 399.  She has become quite well known over time as has had 17 documented cubs, including 3 sets of triplets.  This year, at age 24, she has 4 cubs.399s 4 cubs (Photos are from 399s Facebook page)       Most Grizzly bears don’t make it to that age, let alone emerging from hibernation with cubs of the year.   Well known and respected photographer, Tom Mangelsen has followed her through her lifetime.  “I had a hunch a large litter was in store, because when she lumbered toward her den last fall she was slinging a grizzly gut 2 inches from the ground.  399 and her 4 cubsThis is the third time she has come into view May 18.  Whenever she has cubs of the year, she waits and comes out that day!” one of her triplets, tagged as Bear 610, had twins in 2011.  If you’d like to read more about this well -bear, Tom Mangelsen and Todd Wilkinson together published a book “Grizzlies of Pilgrim Creek, An Intimate Portrait of 399”.

Get outside when you can!   Leslie

You can contact me at!

Photo Credit: Jowayne Curran

News coming from Denise soon!!




GYE Nature News #5 5/15/20

Greetings  everyone,
Dirt is starting to show as the snowline creeps up to higher elevation and the rivers rise and on some days, rivers appear silty with sediment. It’s a neat time of year to witness color and renewal. Some interesting signs are becoming evident showing us what kinds of activity may have occurred while the snow was on the ground. It’s been fun to unravel some of these stories on my recent walks.
Pocket Gophers
Active under the snow, gophers do not hibernate. Their deeper living spaces are where they store food. The more shallow travel tunnels are also foraging corridors. As pocket gophers burrow and excavate the soil, they create the long, worm like casts of dirt that become visible as the snow melts. Sometimes these “tube shaped” gophers are referred to as “Nature’s plowshares”. Their digging is beneficial in the soil as it helps absorb and retain moisture. Grizzly bears enjoy these tasty snacks as well! Pocket gophers are close to ground squirrel size, how very small eyes and ears and large external pockets on the side of their head to carry food to the deeper chambers. Their long claws allow them to dig up to 5 tons of dirt/year!

pocket gopher tunnel
Pocket gopher casting

More bear sign It’s becoming a pattern to include some info about bears! Sign of bears seems to jump out at me. Recently, a friend texted me to let me know she had found remnants of a fox on a morning run and sent me the location. I walked up that way and found the skull and vertebral column, but I also started to find more evidence of a bigger story. Above the fox, hidden in the trees, was a down log that had clearly been excavated, likely by a bear. This is common behavior as they look for insects in the decomposing wood. Another clue was close by; evidence of the age old question if bears poop in the woods! Below the excavated log, chunks of wood and had been dislodged and had rolled down the hill next to this skeleton. We concluded it was a fox for a few reasons. It was clearly a canine by the shape of the skull and teeth. The teeth are much smaller and pointed than a coyote and the back of the skull is more rounded than a coyote. It was also smaller than an adult coyote would have been. My guess is that this fox was not killed by the bear but had died that and been unearthed by the bears rooting behavior. Perhaps the bear had even been attracted by an odor which would have been undetectable to us! My final act before I left was find a new and hidden resting place for this fox.

guess whos rooting around in the woods
Bear excavation


guess who pooped in the woods! - Copy
Bear poop
Fox skull and vertibrate
Fox Skull

More excavation…….This time however, it’s not bears, but squirrels or sometimes even birds. In the photos below are 2 examples of how squirrels will stash cones later in the summer as a food source for the winter months. cone stash 2The cones are cut from the trees when the seeds have developed and then cached in storage piles called middens. Typically these middens are built in small depressions that become covered with the bracts of the cones as the seeds are harvested and eaten in the winter months.





They are stored in the same place year after year and some of these middens can cover large areas, typically under a tree.


Red squirrels can harvest up to 20,000 cones a year! Of course, these squirrels are very territorial as they are protecting their midden. The midden will typically be found in the center of one squirrel’s territory. The size of a territory can be 1-3.5 acres. Below is a red squirrel. Above you’ll see cones in a depression of a midden.


Red Squirrel

Lastly, I wanted to share some of the beautiful blossoms we are starting to see pop! Below is a photo of some of the earliest bloomers, Pasque Flowers (sometimes called Prairie crocus) (Anemone patens, or Pulsatilla patens)

pasque flowers.jpgsmall

Flowers and the Green Wave
Spring is here in the GYE! Seeing wildflowers blooming on the edges of snow patches and coming up through dried grass offers bright color dotting the hillsides and signaling that longer days of spring are here. Many flowers, such as the Pasque flower pictured above, get a jump start on their life cycle and seed production by flowering before grasses and other plants start growing tall. These early bloomers found in sage grassland habitats grow only tall enough to get the maximum sunshine. They have a stem approximately 1-3 inches tall producing what seems to be an oversized flower nodding toward the sunshine. Pasque flowers grow in clusters like a spring bouquet. Their niche of early growth allows flower, pollination, to seed production cycle to finish before other plants out compete them for space and sun. Other early blooming flowers are buttercups (Ranunculus jovis), Glaicer lilies (Erythronium grandiforum), and spring beauty (Claytonia virginica).










Glacier Lily
Glacier lilies (Erythronium grandiforum)


These wildflowers are small bursts of color seen when walking through meadows and mountain sides.

The color that really stands out when scanning the landscape is the green of growing grasses. The “greening up” of meadows starts in lower elevations and on south facing hillsides.

Claytonia_virginica Spring Beauty
Spring Beauty


As the days get longer, air and soil temperatures warm, growing plants and grasses begin growing in higher elevations. We call this progression of growth, the green wave. Many animals like to eat the new grass growth and need this food source in its most nutritious stage including bears and pocket gophers.

Bison Calf
Bison calf, Jim Peaco NPS

Migrating animals such as bison and elk follow this gentle wave of greening grasses along river corridors and valleys and eventually up into higher elevations for the summer. Females with newborn calves need lush and nutritious grasses to produce nutritious milk and start building fat layers depleted after the deep winter snows. Look for newborn bison calves dotting the landscape in May and June in Yellowstone.
The green wave of grass and plant growth fuels spring wildlife migration. The season timing and patterns revolving around this growth are starting to change. More on this next time.

Happy trails, Denise!

Denise w orange pack



Contact Denise at and these Nature updates of GYE can also be found on Big Sky Adventures & Tours website



Sending everyone wishes for good health and time to get outside and appreciate this time of time of year that brings new life and hope. You can contact me at     Leslie

Photo Credit: Jowayne Curran


Nature News from Greater Yellowstone Ecosystem (GYE) #4

Nature Update on the Greater Yellowstone Ecosystem (GYE) #4

Leslie Stoltz and Denise Wade  Yellowstone Naturalists



Photo Credit: Tom Nicholls

Denise w orange pack


Greetings from Yellowstone where we still have a full complement of species that exist here before settlement!  The species diversity and ecological health thriving here is found few places on earth in the 21st century. The Greater Yellowstone is a huge area that land managers call the Greater Yellowstone (functioning) Ecosystem.  It is referred to as a Bioregion: one of the largest intact bioregions in the temperate zones of the world.  As I was writing this I looked at the definition of bioregion:

”Bioregion is a land and water territory whose limits are defined not by political boundaries, but by the geographical limits of human communities and ecological systems. Such an area must be large enough to maintain the integrity of the region’s biological communities, habitats, and ecosystems; to support important ecological processes, such as nutrient and waste cycling, migration, and steam flow; to meet the habitat requirements of keystone and indicator species; and to include the human communities involved in the management, use, and understanding of biological resources. It must be small enough for local residents to consider it home.” 

In our part of the world some of the local residents are Bears. Both Black bear (Ursus americanus) and Grizzly Bears( Ursus arctos) live in Greater Yellowstone.  One big reason Grizzlies can exist here is they have big spaces to roam.  This is ratre on our planet now.

Bear claws
Check out the claws! Leslie Stoltz

Bears have been slowly emerging from winter denning right now and recently, I had the good fortune to observe a Grizzly as he slowly ambled on his way to find some nourishment.  Within the last couple of weeks bear tracks have been seen in the snow.

Bear Tracks for newsletter #4
grizz tracks in snow Leslie Stoltz

This is the first sign of emerging from their dens.  The first to emerge will be the males.  This can be as early as mid-March, depending on weather conditions and food availability.  The last to emerge are the females with cubs, usually later in April.  Cubs are born in the den mid-January.  Mom has not eaten or had any water, nor has she urinated or defecated.  (In fact, a bears waste is reabsorbed and metabolically recycled to form proteins keeping muscle mass from deteriorating!  Another miraculous adaptation for hibernation.) These cubs will be born a pound or less, eyes closed and suckle mom the entire winter….in that little den space! When the young of the year emerge, they will be 5-7 pounds.  Spring is the season when these little “furballs” really start to move around and grow.


399 and cubs (2)
Grizzly #399 Tom Mangelsen

Mom will nurse throughout the spring and summer, but eventually teach them how to find their own food and other survival techniques.  The following winter, the surviving cubs are maybe 30-40 lbs. by that time and they typically den with mom again.


Grizz Den newsletter
grizzly den on north facing slope

Most often they will be in their own dens by the third winter.  Grizzly bears will most often dig a new den every year. They are typically on a north facing slope to be sure enough snow accumulates insulating the den keeping it warm enough with an even temperature throughout the winter.  Often as snow is melting, and the bears have long before emerged, the dens collapse.

Black bears, which evolved to live in more densely forested areas than grizzlies, will often den in spaces under trees or logs or perhaps even in a cave like opening.  BBDen Newsletter

black bear den in cavity under tree

The Black bear has shorter and very curved claws which allow them to readily climb trees.  Grizzly bears have very long claws that help make them “pro-diggers”.    ( See photo above)    Other wild creatures will be emerging as well.  We start to see red squirrels and chipmunks zooming around looking for food.

Notes from Denise

Evidence of the coming spring in the Greater Yellowstone Ecosystem (GYE) can be seen with bear tracks in the snow and mud, and the arrival of migratory birds.


Grizzly and coyote track in snow Denise Wade

Three of my favorites, and some of the first arrivals to the GYE: Red Tail hawks, Sandhill Cranes, and Mountain Bluebirds.  All of these species are short to medium range migrants, spending the winter in the southwestern United States and Mexico, and out of the snow.  However, their early arrival is when the landscape is still blanketed with snow. This timing allows them to take advantage of establishing nesting sites without competition from other species. The common saying “the early bird gets the worm”, really means the best nesting site here in the GYE.

Redtail Hawk Photo YNPRed Tail Hawk

Red Tail hawks (Buteo jamaicensis) are one of the largest in the Accipitridae family, and their favorite foods are small mammals such as mice, voles, ground squirrels, rabbits, and others. They often return to the same nest as the previous year and will spend 4-7 days sprucing it up with bark strips, dried vegetation, and fresh foliage in the center of the 3’ diameter nest.  A tall, sturdy tree with a good view of sagebrush grassland habitat and their prey, dictates the perfect place to nest. Early arrival helps insure a successful nesting season.

Sandhill Crane Photo YNP Jim PeacoSandhill Crane

Sandhill Cranes (Antigone canadensis) known for the elaborate dancing during mating, and often leaving their dance steps visible in the snow for us to see.  Sandhill cranes stand 47” tall with long legs, a long neck, and a large (78”) wingspan.  They nest in marshy areas on the ground and as omnivores, eat seeds, tubers, invertebrates, and small vertebrates. I often hear their loud, warbling, trumpeting call announcing their return to GYE, and the return of spring.

The flash of brilliant blue darting through the air, or perched on a fence post, signals the Mountain Bluebird’s (Sialia currucoides) arrival. They are primarily insect eaters but will also feed on berries such as currants and juniper. Mountain bluebirds nest in tree holes, or cavities, that have been hollowed out previously by woodpeckers or flickers and are referred to as secondary cavity nesters. Their early arrival allows them to establish a prime nesting cavity before other species who might want that same hole, such as tree swallows.  Bluebirds also enjoy nesting in man made boxes on fence posts throughout the GYE

Mountain Bluebird near cavity in Pain Posts
Male mountain Bluebird  Diane Renkin

Check out The Cornell Lab for more info on these birds and many others.


Happy Spring!  Denise      Denise newsletter

Contact Denise at and these Nature updates of GYE can also be found on Big Sky Adventures & Tours website


This has been a very fun project and so nice to be collaborating with Denise. You have the opportunity to read how both of us are experiencing the patterns of seasonal changes. Here’s to these wild places!.   Leslie     

You can contact me at


Nature News from the Greater Yellowstone Ecosystem (GYE) #3


Denise newsletter
LeslieYNPNaturalist Photo Credit: Tom Nicholls

This project is becoming even more fun as friend, colleague and business owner of Big Sky Adventure and Tours will collaborate and share some of her stories!  Together with her business partner they offer educational trips in Yellowstone.  We have worked together for years and experienced many magical events in the outdoors together.

From my window this morning I see a landscape still draped in snow.  A few dry ridgelines show through, but winter is holding on this year. Warmer days create wet and more granular snow, but very cold temps at night causes the snow to harden into a hard, icy layer called crust. Out in the morning the crust reveals the story of the previous day in a frosted crystaline glass gallery.

It’s very fun to put the story together of what happened the day before by following the tracks. Below is another photo you may want to guess what could have happened.

raven wings in snowYou probably guessed this was a bird, a Raven,that landed, perhaps to pick up a mouse.  My guess is Raven because of the distinct flight feathers and size. If it were an owl, which would have downy fuzz on the feathers for silent flight, the feathers would look less clear. If you want to see a photo of the Raven, just look at top photo and you’ll see one of these tricksters on my head!

From Denise

The story of tracks in the snow can be a Shakespearian tragedy where “fair is foul, and foul is  fair”. Cross country skiing a few days ago, we came upon such a drama.Wolf Tracks and my hand April 14 2020.jpg 2
In the delicate and light snow crystals on top of a firm crust were fresh canine tracks-some large ones next to a much smaller single set. They both have 4 toes with claw marks visible. We continued up the trail, crossing the tracks many times. Sometimes the tracks were separate, sometimes all together. This was clearly two wolves following a coyote.
Wolves are loyal defenders of their territory, especially from other canines, and around their denning site. The firm crust made it easy for the much larger wolves to easily travel on top and quickly follow the coyote.

A scuffle in the snow appeared in several spots with the heavier wolves slightly breaking through, and the lighter coyote staying on top. Revealed in the snow were patterns of the coyote getting pinned, and then running away. The chase continued down the creek gully. Later we came upon the coyote’s final battle.

dead coyote 4.17.20 (1)

Sometimes the drama is not about dominance but is an illustration of Maslow’s hieragrizz skier tracks 3rchy of needs: food, shelter, water. A grizzly bear just coming out from his long winter deep sleep state, is looking for high calorie food. With feet of snow still on the ground, meals can be challenging to find. A grizzly’s nose and nasal mucosa is 100 times greater than ours, and 7 times more sensitive than a bloodhound. Notice two different tracks in this photo. One looks like “Bigfoot” but actually is the bear’s hind foot. The other track is the front foot with his front pad and 5 toes and claws showing in the snow. The bear’s front foot heel is not visible in this track. The grizzly walks with his front feet turned in slightly, and the back foot steps in the front foot track, or just in front as shown here.

This bear found dinner digging out a beaver lodge as seen below.

Grizz beaver lodge
Photo Credits: Denise Wade

The snow falling today will cover the stage making for new illustrations of drama tomorrow.

Denise on skis

Photo Credit: Jowayne Curran

This has been a very fun project and so nice to be collaborating with Denise. You have the opportunity to read how both of us are experiencing the patterns of seasonal changes. Here’s to
these wild places! Leslie

You can contact me at

You can find Denise’s travel company      

Nature News from the Greater Yellowstone Ecosystem (GYE) #2

Last night the temperature dropped to -10 degrees F. That came as a surprise to us (sort of) but maybe not for all the creatures with whom we share this place.  This kind of event is not unusual in the Greater Yellowstone area. Even prior to changing climates it was typical for us to experience what seemed like the arrival of spring with melting snow and warmer temperatures, only to have a few winter storms and cold fronts come through.  Over the last days we’ve had a tremendous number of Gray Jays  Perisorius canadensis, Steller’s Jays Cyanocitta stelleri , Clark’s Nutcrackers Nucifraga columbiana , Mountain Chickadees Parus gambeli, Red Breasted Nuthatches Cita canadensis and recently Dark-eyed Juncos Junco hyemalis feverishly gathering seed  I threw outside (no feeders as bears are emerging from their dens) and stuffing their crops.

Mountain Chickadee

Fat birds have a better chance of surviving cold weather and can sense a change in air pressure indicating a weather change. Another adaptation which helps these flying creatures is (you guessed it) feathers!  Fluffy down feathers and expanding space between quill feathers help trap body heat and keep the cold temps away from their skin. Some of these species will roost together in a very sheltered conifer tree, crevices in the bark or anywhere that will keep them protected from the coldest of temperatures and wind.

These late severe temperature changes can be disastrous for some individuals.  Nesting has begun for a few of these species and fluctuations like this can stop an early nesting attempt.  If there has been any early molting, it can cause an inability to create warm airspaces as they fluff up their feathers.  This may prevent them from keeping body temperatures high enough to survive a cold night.  With a spring freeze it can become very difficult to find open water. All life forms need this for survival. The crust of ice that forms on the surface of the snow can make it impossible for birds to get to their caches they have stored for winter food sources. Steller’s Jays, Gray Jays, Clarks Nutcrackers, Mountain Chickadees and Red Breasted Nuthatches are all known to cache food.  If food is not available, birds may move to an area where it is more abundant.  So if later that year, you don’t see as many of your favorite species, don’t fear.  It may not be they didn’t survive the spring freeze; it could be they have moved on to greener pastures.


Gray Jay with a full beak

Corvids (not Covid, as in19, just a play on words for these times….) are a family of birds, including some I mentioned above.  Jays, Nutcrackers, Ravens, Crows and Magpies are all members of this family. This family of birds is considered a considered a highly intelligent bunch.  Stories of ravens, jays, magpies and other Corvidae go back through time and point to birds that are adaptable, can learn, analyze situations, problem solve, care for their injured or sick and grieve the deaths of fellow individuals.  Neurologist, Stanely Cobb, researched a part of this avian brain called the “hyperstriatum”.  Mammals lack this. The larger this part of their brain, the higher they perform on tasks indicating intelligence. Corvids are at the high end of these tests and are tops among birds for brain size!

Stellar’s Jay

Candace Savage (Author of “Bird Brains; the intelligence of Crows, Magpies, Ravens and Jays” is the source of so much Corvid information) says “very smart animals tend to be social”. She uses humans, dolphins, whales, parrots and corvids as examples of this.  Watch a group of any of these species and you will observe some of the most interesting, humorous and often playful behavior.
Steller’s Jay and Blue Jay are the Corvids with crests.  Both have large vocabularies and the ability to mimic. Sometimes out in the woods thinking I hear a Red Tailed Hawk I look up to realize I’ve been tricked by a Steller’s Jay once more!

Photo Credit: Jowayne Curran

Thanks so much for reading this newsletter. It can be found as a blog on the website In this time of “self-isolation”, I find great joy in immersing myself and writing a bit about the world around me. I encourage you to look there for peace and solace. A friend wrote me today…

It’s interesting to think about how the human world has been turned upside down, but that the rest of nature just marches forward undaunted.”

Please pass this on to friends who might enjoy.   Leslie

You can contact me at