Episode Archive - Page 176 of 221

February 16, 2012March 4, 2026

Snowy Owl Invasion

Click for a larger view of the tethered Snowy Owl, Bubo scandiacus, Image courtesy US FWS. Ronald Laubenstein, Photographer — Tethered Snowy Owl in Alaska
*Bubo scandiacus*
Courtesy US FWS
Ronald Laubenstein, Photographer
Snowy Owl in Alaska
*Bubo scandiacus*
Courtesy Wikimedia
Floyd Davidson, Photographer
Licensed under the
Creative Commons: GNU Free Documentation License
Snowy Owl with Chick
*Bubo scandiacus*
Courtesy Wikimedia
Tony Hisgett, Photographer
Licensed under the
Creative Commons: Attribution 2.0 Generic License
Snowy Owl in Flight
*Bubo scandiacus*
Courtesy Wikimedia
Bert de Tilly, Photographer
Licensed under the
Creative Commons: Attribution-Share Alike 3.0 Unported License

Click for a larger view of Snowy Owl in Alaska, Bubo scandiacus, Photo taken in Alaska by Floyd Davidson, Photographer, Courtesy Wikimedia and licensed through GNU Free Documentation License 1.2 — Tethered Snowy Owl in Alaska
*Bubo scandiacus*
Courtesy US FWS
Ronald Laubenstein, Photographer
Snowy Owl in Alaska
*Bubo scandiacus*
Courtesy Wikimedia
Floyd Davidson, Photographer
Licensed under the
Creative Commons: GNU Free Documentation License
Snowy Owl with Chick
*Bubo scandiacus*
Courtesy Wikimedia
Tony Hisgett, Photographer
Licensed under the
Creative Commons: Attribution 2.0 Generic License
Snowy Owl in Flight
*Bubo scandiacus*
Courtesy Wikimedia
Bert de Tilly, Photographer
Licensed under the
Creative Commons: Attribution-Share Alike 3.0 Unported License

Hi, I’m Holly Strand.

Maybe you’ve seen some headlines or blog titles this winter: Snowy owls invading the US or Scientists bewildered by mass migration of snowy owls from the Arctic.

What’s going on? The thought of bewildered scientists makes me uneasy. Should we be concerned or should we be delighted at the prospect of maybe seeing one of these ethereal birds?

A dramatic increase of a single species outside its usual habitat is called an irruption—that’s irruption with an “i” not an “e.” Snowy owl irruptions are usually attributed to periodic spikes in the population of their favorite snack—the lemming. In an a year with plentiful food resources, an owl can lay up to 10 or 11 eggs! Having lots of baby snowy owls in the nest forces the parents to hunt more. Eventually, the lemming supply crashes and by winter you have a large, hungry population of owls, some of which must disperse far and wide to search for food.

A rise and fall of lemming numbers likely did occur in 2011, causing a lot more snowy owls to move south. But is this year really as amazing as it seems? Consider: The number of people birding in 2001 grew 232 percent above the number involved in birding in 1983. And the total has grown still more over the last decade. More bird counters = more sightings. In fact, a single bird might be sighted and counted many times by these rapidly multiplying bird counters.

Furthermore, the counters–and even people who don’t count—are recording and storing all their personal bird sightings online. The most popular storage tank is a checklist program called eBird. Personal and group records in eBird are amassed together into a giant global database. Ebird uses this database to create figures, summaries and maps which are available to anyone. It’s eBird’s map of snowy owls that is being cited in blogs and newspaper articles. The map clearly shows a remarkable number of snowies decending upon the lower 48 especially in the Great Plains region. Everyone can agree that it’s a great year but still, you can’t help but question if the much higher counts are partly due to the spiraling rates of human counting and reporting.

Here in Utah there have been two recorded sightings this winter—one in the Bear Lake Valley and one on the causeway to Antelope Island. Not what I’d call an invasion, but these two sightings do represent the first ever records of snowy owls on Ebird. However, if you snoop around enough you’ll find there have been sporadic sightings in Utah dating back to 1908.

For pictures, sources and links go to WWW.Wildaboututah.org

For Wild About Utah, I’m Holly Strand.

Credits:

Images: Courtesy US FWS, Ronald Laubenstein, Photographer; and
Courtesy Wikimedia, Photographers: Floyd Davidson, Tony Hisgett, Bert de Tilly.
Text/Voice: Holly Strand

Sources & Additional Reading:

eBird [Accessed February 16, 2012]. Distribution and frequency map machine. https://ebird.org/ebird/map/snoowl1?&eyr=2012 and The Winter of the Snowy Owl (February 2, 2012) https://ebird.org/content/ebird/news/the-winter-of-the-snowy-owl

Kerlinger, P. and M. Ross Lein. 1988. Population Ecology of Snowy Owls during Winter on the Great Plains of North America in The Condor, Vol. 90, No. 4 pp. 866-874. URL: https://www.jstor.org/stable/1368844 [Accessed February 15, 2012]

Parmelee, David F. 1992. Snowy Owl (Bubo scandiacus), The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America Online: formerly: https://bna.birds.cornell.edu/bna/species/010 [Accessed February 16, 2012]

Snowy Owl, Birds of the World, The Cornell Lab of Ornithology, Cornell University, https://birdsoftheworld.org/bow/species/snoowl1/cur/introduction

Utah Birds Rare Bird sightings in Utah https://www.utahbirds.org/RecCom/RareBirds3.htm#SnowyOwl[Accessed February 16, 2012]

Link to Youtube video “Snowy Owl Invasion” produced by the Cornell Lab of Ornithology: https://www.youtube.com/LabofOrnithology [Accessed February 16, 2012]

Alternate URL: https://www.youtube.com/watch?v=Ufkcx-UqljM&list=PLA20B4F3F9F421EC9

Webmaster picks:

Laura Erickson, The Owls of Harry Potter, https://lauraerickson.com/bird/Species/Owls/HarryPotter/HarryPotter.html

Snowy Owls swoop down from the arctic, Kristen Dahlgren, MSNBC, https://video.msnbc.msn.com/nightly-news/46228248#46228719

Photographer waited ‘long time’ for snowy owl to come back, MSNBC, https://video.msnbc.msn.com/nightly-news/46228248#46228248

Reaction to Snowy Owl “Wow”, MSNBC, https://video.msnbc.msn.com/nightly-news/46228248#46226508

February 9, 2012March 4, 2026

Wilderness, Much Closer Than You Think

The word conjures up romantic images of wide open landscapes teeming with birds, beasts, and plants. I imagine places untouched by human influence – truly wild and free. Places that are exotic and far away.

But wilderness exists much closer than you may think.

The United States Congress adopted the Wilderness Act with a nearly unanimous vote in 1964. Ours was the first country in the world to define and designate wilderness areas – lands valued enough to be set aside for the purpose of protection.

Currently, the Wilderness Act protects 757 individual wilderness areas across the United States – totaling more than 109 million acres. Thirty-three wilderness areas are found in Utah, and they protect a variety of unique landscapes from the red rock desert found in Red Butte Wilderness to the alpine forests of the High Uintas Wilderness. While the landscapes may look incredibly different from one wilderness area to the next, these lands share a number of qualities which can be described by adjectives such as peaceful, quiet, untouched, and pristine.

These areas protect some of the most unique and incredible landscapes that Utah has to offer, but that doesn’t mean they’re off limits. Our wilderness areas are just that – ours. They are public lands, accessible to anyone who wants to visit – so long as you tread lightly.

Areas that fall under its protection are described in the Wilderness Act as “lands designated for preservation and protection in their natural condition…” which “…shall be devoted to the public purposes of recreation, scenic, scientific, educational, conservation and historic use.” These amazing lands were set aside in 1964 with an eye to the future and because of it, should still be around for your grandchildren’s grandchildren to enjoy.

There is an ongoing effort to educate Americans about the immense value of preserving wilderness areas. For without education, they may one day be selfishly reclaimed and lost. One of these educational opportunities is coming to Logan on April 13th and 14th. The Arthur Carhart National Wilderness Training Center will be hosting a teacher training workshop in conjunction with the Stokes Nature Center and the Utah Society for Environmental Education. The workshop is aimed at teachers in grades 5-8, though anyone is welcome to attend. For more information, please contact the Stokes Nature Center at www.logannature.org

Not a teacher? The best way to learn about wilderness areas is to go visit one! Information, and photos of Utah Wilderness Areas, can be found at www.wildaboututah.org

For the Stokes Nature Center and Wild About Utah, this is Andrea Liberatore.

Credits:

Photos: Courtesy Wilderness.net, Steve Archibald, (Individual Copyrights noted)
Text: Andrea Liberatore, Stokes Nature Center, logannature.org

Additional Reading:
The Arthur Carhart National Wilderness Training Center:
wilderness.net

Wilderness Investigations teacher training workshop:
logannature.org/wi_workshop

Public Law 88-577 a.k.a. Wilderness Act, Sept 3, 1964, U.S. Government Publishing Office: https://www.govinfo.gov/content/pkg/STATUTE-78/pdf/STATUTE-78-Pg890.pdf

February 2, 2012March 10, 2025

Snow Pack Dynamics

Click for more information on Snow Layers. Graphic Courtesy Forest Service Avalanche Center www.fsavalanche.org — Snow Layers
Courtesy:
Forest Service Avalanche Center
Jim Conway, Graphic Artist
Formerly fsavalanche.org
See: https://avalanche.org/avalanche-encyclopedia/#snow-layer

Depth Hoar
Click to watch archived animation
Courtesy:
Forest Service Avalanche Center
Jim Conway, Graphic Artist
Formerly fsavalanche.org
See: https://avalanche.org/avalanche-encyclopedia/#depth-hoar-basal-facets

See Archived Avalanche Encyclopedia https://web.archive.org/web/20100312232112/http://www.avalanche.org/~uac/encyclopedia/

Click for more information on Depth Hoar. Graphic Courtesy Forest Service Avalanche Center www.fsavalanche.org — Snow Layers
Courtesy:
Forest Service Avalanche Center
Jim Conway, Graphic Artist
Formerly fsavalanche.org
See: https://avalanche.org/avalanche-encyclopedia/#snow-layer

Depth Hoar
Click to watch archived animation
Courtesy:
Forest Service Avalanche Center
Jim Conway, Graphic Artist
Formerly fsavalanche.org
See: https://avalanche.org/avalanche-encyclopedia/#depth-hoar-basal-facets

See Archived Avalanche Encyclopedia https://web.archive.org/web/20100312232112/http://www.avalanche.org/~uac/encyclopedia/

Water is our planet’s magical molecule, changing states faster than a presidential candidate. Snowpacks vaporize, ice melts and re-freezes, lakes evaporate, and cooled water vapor condenses back as clouds, snowflakes and hoarfrost. The muffled silence of the winter snowpack belies its dramatic pace of transformation.

In his book entitled “Life in the Cold”, author Peter Marchand explains the dynamic nature of the snowpack. Within a few hours after a snow storm, destructive metamorphism sets to work on the newly fallen snow. The delicate crystalline structure of each snowflake is quickly degraded. The intricate flakes transform to amorphous icy grains. Wind, warmth and compression accelerate destructive metamorphism, leaving a firmer, denser snowpack. At the surface, not only does snow strongly reflect the weak warmth of winter sunlight, but on a clear night, it radiates energy, greatly cooling the surface.

Meanwhile, the soil beneath the snowpack is typically warmer than the overlying snow, which is why springs can run all winter long. Three feet underground, soil temperature is within a few degrees of that location’s average annual air temperature. Sandwiched between the warm soil and the cold air, the blanket of snow is a great thermal insulator; fresh snow is the equal of fiberglass insulation. As a result, soil warmth transforms snow deep under the snowpack into water vapor. This moisture spreads through air spaces in the snowpack, following the thermal gradient to the chilly snow surface. As the moisture vacates the lower layers, a brittle porous layer develops in the snowpack. Termed “depth hoar”, it is weak, icy and prone to collapse. When the heavy overlying snowpack shifts, the crumbly depth hoar can release an avalanche, a powerful reminder of snowpack transformations for any backcountry traveler.

Come spring, every particle of Utah’s snowpack undertakes its final transformation. Some sublimates to waft away on warm springtime winds. Most of it melts away to feed the groundwater, springs and streams that give us cool relief on a hot summer day and provide the precious water that every Utahn depends on.

This is Linda Kervin for Bridgerland Audubon Society.

Credits:

Graphics: Courtesy Forest Service Avalanche Center, https://www.fsavalanche.org/
Text: Jim Cane, Bridgerland Audubon Society

Additional Reading:

Life in the Cold by Peter Marchand:https://www.upne.com/9619460.html

Forest Service National Avalanche Center, Avalanche Awareness Website: https://www.fsavalanche.org/

Depth Hoar: https://www.fsavalanche.org/encyclopedia/depth_hoar.htm

Utah Avalanche Center: https://utahavalanchecenter.org/

January 26, 2012April 8, 2021

The Shape of Wildlife in Winter

Hi, this is Mark Larese-Casanova from the Utah Master Naturalist Program at Utah State University Extension.

Now that snow is finally accumulating in Utah’s mountains, weekend hiking trips have come to an end. But, that means it’s time to dust off the snowshoes and skis and get back outside. We humans are lucky in that we have countless types of gear to help us adapt to almost all winter conditions.

While a fur coat might help keep mammals warm or camouflaged in winter, there are many other adaptations that also aid in winter survival. Decreased mobility in deep snow can often prevent animals from finding food, possibly causing starvation in winter.

Some animals have feet that are particularly large for their body size, which helps them travel on top of deep snow. One of the best examples of this adaptation can be found in snowshoe hares. Snowshoe hare prints are easy to spot among the spruce and fir trees- the large teardrop-shaped hind feet leave prints that look like the hare was wearing miniature snowshoes, which is how it got its name.

While some animals are adapted to walk on top of deep snow, others do their best to simply walk though it. The long, slender legs of moose help keep the majority of their bodies above the snow, minimizing the energy required to travel in winter.

Instead of walking on top of or through the snow, small mammals such as mice and voles travel under the snow. As snow accumulates, mice and voles create vast networks of tunnels on top of the ground, but under the snow. This subnivean environment is typically warmer than air temperature above the snow, and still provides access to food, such as grasses, seeds, and bark.

Short-tailed weasels, also known in winter as ermine, have a long, slender body shape that allows them to invade subnivean tunnels to prey upon smaller mammals. As long as its head can fit into a tunnel, its narrower body can follow. This adaptation comes with a price, though. Slender bodies lose heat quickly, so weasels must consume around one-third of their body weight in food each day in order to produce enough heat to survive.

So while deep powder might seem like a winter wonderland to those of us who can adapt with the right gear, other mammals continually struggle to stay warm and find food. Some, however, choose to give up the fight and sleep the winter away.

For Wild About Utah, I’m Mark Larese-Casanova.

Credits:

Images: Pending rights approval
Text: Mark Larese-Casanova, Utah Master Naturalist Program at Utah State University Extension.
Additional Reading:

Ellsworth, E. Surviving the winter: The importance of snowshoe hare foraging behavior. BEHAVE: Stories of Applied Animal Behavior. University of Idaho. Available at: https://www.cnr.uidaho.edu/range556/appl_behave/projects/hare_forage.html

Gellhorn, J. (2002). Song of the alpine: The Rocky Mountain tundra through the seasons. Johnson Books.

Lieberg, A. (2009). Charismatic minifauna. Northwest Connections. Available at: https://www.northwestconnections.org/documents/news/EOE_09feb26_Lieberg.pdf