Archives: Episode

Posted on

The smell of rain

Electron micrograph showing
the filamentous structure of
actinomycetes
Photo Courtesy:
Soil Science Society of America

Spring is my favorite season. I love watching our landscape turn from brown to green, the first butterfly sighting, and the rain. During a recent April shower, I stepped outside and inhaled that magical springtime scent – the smell of rain. Which got me thinking – what is that smell, anyway?

What seems like a simple question, begs a complicated answer. That smell, however, does have a name – petrichor – and there are many things that contribute to its scent. One of the biggest culprits may actually be soil bacteria – mostly from the genus actinomycetes – which grow in unfathomable concentrations in soils all around the world. These bacteria play an important role in decomposition and soil health. Periods of relative dryness trigger their reproductive cycle, causing the production of spores, which are considerably more drought-tolerant. When rain finally does fall, the spores are launched into the air, where they may eventually reach our nose. Scientists have identified the chemical compound responsible for the spore’s odor and have named it geosmin, which literally translates to ‘earth smell.’

Humans noses are particularly sensitive to geosmin, but we’re not the only ones. Camels, too, are sensitive to its smell and some scientists believe this helps them find oases in the desert. Our ability to detect this odor might be a throwback to our nomadic ancestors for whom finding water in a vast landscape was of utmost importance.

But the scent trail doesn’t end with geosmin. The chemical compound ozone may also be a part of petrichor especially after a thunderstorm, as ozone is produced by lightning. Another aroma is provided by chemicals called volatile oils which are produced by all plants, and which collect on the ground during dry periods. With rain, they evaporate into the air, contributing to the musty, earthy odor. Acidic rain has also been shown to create scents by reacting with chemicals on the ground such as spilled gasoline. And further complicating the matter is the fact that rain hitting the earth throws dust and other particles from countless sources into the air.

If all of these smells are around us all the time, why is it that they are distinctly associated with rain? The answer lies in the properties of odors and how they travel. Everything that produces a scent is releasing chemical compounds into the air. The ability to evaporate – or volatility – of these compounds increases with the heat and moisture levels of the air around them. The humid air that produces rain creates ideal conditions for conveying scents to our noses.

In the end, it’s not the rain itself that causes odor, but the interaction of water and a number of chemical and organic compounds. Test this theory at home by throwing a bucket of water on the lawn or a hot driveway to see if you can recreate the smell of rain. Likewise, smell a stick, leaf, or rock when it is dry, then wet it and see how the odor changes. For those seeking answers to the origins of the smell of rain, it’s often best to follow your nose.

Thank you to the Rocky Mountain Power Foundation for supporting the research and development of this topic.

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

Credits:
Images: Photo Courtesy Soil Science Society of America
Text:     Andrea Liberatore, Stokes Nature Center in Logan Canyon.
Special thanks to Joel Martin from the Utah Climate Center
Additional Reading:

National Public Radio (2007) The Sweet Smell of Rain. All Things Considered, August 11 2007. Interview of Dr. Charles Wysocki by Debbie Elliott. Transcript available online at: https://www.npr.org/templates/story/story.php?storyId=12716163

Gerritsen, V.B. (2003) The Earth’s Perfume. Protein Spotlight, Issue 35. Accessible online at: https://web.expasy.org/spotlight/back_issues/035/

Gerber, N.N, and Lechevalier, H. A., (1965) Geosmin, an Earthy-Smelling Substance Isolated from Actinomycetes. Applied Microbiology. 13,6. Accessible online at:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1058374/pdf/applmicro00362-0105.pdf

Live Worldwide Network for Lightning and Thunderstorms in Real Time, Blitzortung, https://en.blitzortung.org/live_lightning_maps.php?map=30

Posted on

Songs of the Western Meadowlark, Poorwill and Canyon Wren

Songs of the Western Meadowlark, Poorwill and Canyon Wren: Western Meadowlark. Courtesy US FWS https://images.fws.gov. John and Karen Hollingsworth, Photographers
Western Meadowlark
Sturnella neglecta
Courtesy US FWS
John & Karen Hollingsworth,
Photographers, images.fws.gov

Common Poorwill. Courtesy Dominic Sherony, Photographer, Licensed under CCA-Noncommercial 3.0 Unported Common Poorwill
Phalaenoptilus nuttallii
Dominic Sherony, Photographer
formerly linked to: https://www.birdphotos.com/photos/index.php?q=gallery&g2_itemId=85245
Licensed under
CCA-Noncommercial 3.0 Unported

Canyon Wren, Catherpes mexicanus, Courtesy & Copyright © 2007,Lou Giddings, Photographer Canyon Wren
Catherpes mexicanus
Courtesy & Copyright © 2007,
Lou Giddings, Photographer
UtahBirds.org

Everyone recognizes bird-watchers by their binoculars. Bird-listening, on the other hand, takes nothing more than your ears, and attention to Nature’s sounds. Listening for bird songs may require your concentration at first, but soon it becomes second nature. Some common birds of Utah are more easily found and known by their song than their appearance.

The Canyon Wren is one of my favorites. This tiny cinnamon-brown bird weighs little more than a marshmallow, but it belts out a cascading song big enough to reverberate off the rocky cliffs and slopes that are its home.

[Kevin Colver recording: Birds of the South West Canyon Country, https://wildstore.wildsanctuary.com/collections/special-collections]

You may not see the canyon wren, but try conversing with it by whistling its song in reply. Listen year-round for its song throughout Utah and our neighboring states, particularly in canyons with rocky walls.

Nocturnal birds are seldom seen but commonly heard. Owls are an obvious example, but so is the

Common Poorwill, a migrant whose call is diagnostic throughout Utah.

[Kevin Colver recording: Birds of the Rocky Mountain Foothills, https://wildstore.wildsanctuary.com/collections/special-collections]

Poorwills are camouflaged ground-nesters. On summer evenings, though, you may occasionally see them settled on pavement, their eyes reflecting headlight beams, looking like glowing coals.

Bird song can help distinguish between related bird species too. On the eastern Great Plains, both Eastern and Western Meadowlarks co-occur. The plumage of these two starling-sized species is nearly identical, but their songs differ dramatically. The eastern species sings but a few clear notes, but our western meadowlark sings a beautiful musical warble.

[Kevin Colver recording: Birds of the South West Canyon Country, https://wildstore.wildsanctuary.com/collections/special-collections]

Meadowlarks reside here year-round, typically in grassy areas, pastures and foothills. Their backs are brown, but the male’s chest is a brilliant lemon yellow. Males are frequently seen singing their cheerful song atop a fence post. And that is another reason for listening to birds, for the sheer pleasure of their song.

This is Linda Kervin for Bridgerland Audubon Society.

Credits:

Graphics: Courtesy US FWS images.fws.gov
Recordings: Kevin Colver, https://wildstore.wildsanctuary.com/collections/special-collections
Text: Jim Cane, Bridgerland Audubon Society
Voice: Linda Kervin, Bridgerland Audubon Society

Additional Reading:

Western Meadowlark, UtahBirds.org, Utah County Birders, http://www.utahbirds.org/birdsofutah/ProfilesS-Z/WesternMeadowlark.htm

Common Poorwill, UtahBirds.org, Utah County Birders, http://www.utahbirds.org/birdsofutah/Profiles/CommonPoorwill.htm

Canyon Wren, UtahBirds.org, Utah County Birders, http://www.utahbirds.org/birdsofutah/Profiles/CanyonWren.htm

Western Meadowlark, All About Birds, Cornell Lab of Ornithology, https://www.allaboutbirds.org/guide/Western_Meadowlark

Common Poorwill, All About Birds, Cornell Lab of Ornithology, https://www.allaboutbirds.org/guide/Common_Poorwill/overview

Canyon Wren, All About Birds, Cornell Lab of Ornithology, https://www.allaboutbirds.org/guide/Canyon_Wren

Posted on

The History of Our National Forests

Civilian Conservation Corps
enrollees clearing the land
for soil conservation
Photo Courtesy National Archive
Franklin D. Roosevelt Library (NLFDR)

Terraces near Mount Nebo trailhead
Payson Canyon
Photo Courtesy & Copyright © 2011
Lyle W. Bingham, Photographer

Albert Potter
Photo Courtesy USDA Forest Service
The Greatest Good
A Forest Service Centennial Film

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

Warm springtime weather brings clear trails up in the mountains, and hiking through the shade of Douglas-fir on a warm weekend day had me wondering about Utah’s National Forests and how they came to be.

Back in the days of the early pioneers, Utah’s mountains were recognized as resources for survival, providing clean water for drinking and irrigation and lumber for building homes. The high mountain pastures were also valuable summer forage for livestock. In the late 1840’s, Parley Pratt declared, “The supply of pasture for grazing animals is without limit in every direction. Millions of people could live in these countries and raise cattle and sheep to any amount.” Many settlers shared this view, and unmanaged grazing resulted in deteriorated rangelands in just 20 to 30 years. By 1860, some Utah towns were experiencing regular flooding and heavy erosion due to insufficient vegetation to stabilize the soil. Unregulated wholesale timber harvesting during the same period also contributed to these conditions.

In 1881, the US Department of Agriculture’s Division of Forestry (later renamed the Forest Service) was established, and its first job was to gather information about the condition of the nation’s forests. In 1902, Albert F. Potter, who was the inspector of grazing for the General Land Office, conducted a survey of potential Forest Reserves in Utah. Potter stated that “the ranges of the State have suffered from a serious drought for several years past, and this, in addition to the very large number of livestock, especially of sheep, has caused the summer range to be left in a very barren…condition.”

The demand for lumber and wool during the First World War again led to increased timber harvesting and grazing on our forests. During the Great Depression of the 1930’s, Franklin D. Roosevelt established the Civilian Conservation Corps (CCC) to help implement conservation projects across the country. The CCC was fundamental in re-foresting much of the Wasatch and Uinta Mountain ranges, planting over three million trees in nine years.

Utah’s Forest Reserves were created in the years soon after Albert Potter’s surveys, and were gradually combined into Utah’s seven National Forests that now cover approximately 10,500,000 acres, or about 20%, of the state. Grazing and timber harvesting still occur on much of Utah’s National Forests, but our practices are supported by scientific research and over a century of experience, ensuring more sustainable multiple use and management of our forests today.

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

Credits:
Images: Courtesy National Archives, Franklin D. Roosevelt Presidential Library
              and Courtesy and Copyright © 2011 Lyle W. Bingham
Text:     Mark Larese-Casanova, Utah Master Naturalist Program at Utah State University Extension.


Additional Reading:

Baldridge, K.W. The Civilian Conservation Corps in Utah. Utah History To Go.
https://historytogo.utah.gov/utah_chapters/from_war_to_war/thecivilianconservationcorps.html

Prevedel, D.A., and C.M. Johnson. 2005. Beginnings of Range Management: Albert F. Potter, First Chief of Grazing, U.S. Forest Service, and a Photographic Comparison of his 1902 Forest Reserve Survey in Utah with Conditions 100 Years Later. United States Department of Agriculture, US Forest Service. R4-VM 2005-01. https://www.fs.fed.us/rm/pubs_other/r4_vm20005_01.pdf

Posted on

Who’s Afraid of the Big Bad Wolf?

Who’s Afraid of the Big Bad Wolf: Yellowstone Gray Wolf, Photo Courtesy US FWS. Tracy Brooks, Photographer
Yellowstone Gray Wolf(Canis lupus)
Photo Courtesy US FWS
Tracy Brooks, Photographer

Who’s Afraid of the Big Bad Wolf: Yellowstone Gray Wolf with Radio Collar, Photo Courtesy US FWS, William Campbell, PhotographerYellowstone Gray Wolf(Canis lupus)
With Radio Collar
Photo Courtesy US FWS
William Campbell, Photographer

Hi, I’m Holly Strand.

In January, a movie called “the Grey” briefly flashed across theater screens. The plot pits man against nature: after a plane crash in the Alaskan wilderness, 7 men struggle to return civilization. In the process, the group is whittled down one by one, victims of ferocious and hungry wolves.

Author Barry Lopez says the wolf as human predator is a theme that runs deep into the human psyche. Thus, this movie is just the latest in a long line of wolf eats man stories. Little Red Riding Hood maybe the most famous example. Aesop’s fables are full of wolves with questionable intentions. The tale that chills me the most is a flashback within Willa Cather’s My Ántonia. Riding sleds in a snowstorm, an entire wedding party is attacked and then devoured by a pack of hungry wolves, the bride screaming in terror until she is taken down and finished off….. Ugh.

On the other hand we have legends and accounts that praise the wolf as noble and even familial. Many native American groups revered the wolf for its strength and survival skills.

The founders of Rome, Romulus and Remus were supposedly raised by wolves, as was Mowgli in Rudyard Kipling’s Jungle Book. In 1963 Farley Mowat published Never Cry Wolf, which led many people to see wolves in a more sympathetic light.

So how do wolves regard humans? Are we a creature to be avoided or are we dinner entrees?

Not long ago, a team of researchers examined the data on wolf attacks from a handful of European countries plus North America. From these records they drew the following conclusions:

  1. The majority of attacks on humans involve wolves with rabies.
  2. Among non-rabid attacks, most victims were children, and to a lesser extent, adult women.
  3. When wolves lose their fear of humans, attacks increase dramatically.
  4. Wolf–dog hybrids are innately less fearful of humans, making them extremely dangerous.
  5. And lastly—and not surprisingly—provoking a wolf is likely to incite an attack. Cornering a wolf or entering a den with pups is not a good idea.


The study also confirmed that the number of attacks on humans has dropped dramatically in the last century. This is not just because there are fewer wolves. It’s that the situations leading to attacks are not common anymore:

For instance, the incidence of rabies has dropped dramatically in North America and Europe.

And we no longer send our children out alone to tend sheep or other livestock, an invitation for a wolf attack.

Another factor is that legislation has curtailed the breeding of wolf-dog hybrids. Now 40 U.S. states effectively forbid the ownership, breeding and importation of wolf-dogs, while others impose some form of regulation upon ownership.

In summary, the consensus of wolf specialists is that under normal circumstances people aren’t on the wolf’s menu. Bears, cougars, tigers and other large carnivores are more likely to attack humans.

For Wild About Utah, I’m Holly Strand.


Credits:

Images: Courtesy US FWS https://images.fws.gov
Text: Holly Strand

Sources & Additional Reading:


Carnahan, Joe. Director. 2012. The Grey https://www.imdb.com/title/tt1601913/

Linnell, J.D.C., R. Andersen, Z. Andersone, L. Balciauskas, J.C. Blanco, L. Biotani, S. Brainerd, U. Breitenmoser, I. Kojola, O. Liberg, J. Loe, H. Okarma, H. Pedersen, C. Promberger, H. Sand, E. Solberg, H. Valdmann, P. Wabakken. 2002. The fear of wolves: A review of wolfs attacks on humans. NINA Oppdragsmelding: 731:1-65. https://www.lcie.org/docs/damage%20prevention/linnell%20nina%20op%20731%20fear%20of%20wolves%20eng.pdf

Löe J. and E. Röskaft. 2004. Large Carnivores and Human Safety: A Review. AMBIO: A Journal of the Human Environment Aug 2004 : Vol. 33, Issue 6, pg(s) 283-288

Lopez, Barry. 2004. Of Wolves and Men. Twenty-fifth anniversary edition, Scribner.

Mech, L. David. 1991. The way of the wolf. Voyageur Press, Stillwater, MN

Palamar, Colette. A History of Attitudes Toward Wolves. University of Idaho.

https://www.class.uidaho.edu/kpgeorge/issues/wolves_history/history_symbol.htm [accessed April 18, 2012]

Silver, Marc. 2012. Would Real Wolves Act Like the Wolves of ‘The Grey’? National Geographic interview of Daniel MacNulty, Utah State University. [accessed April 18, 2012]