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A New Winter Coat

Snowshoe Hare Summer Coat
Lepus americanus
Photo Courtesy US NPS


Snowshoe Hare Winter Coat
Photo Courtesy USDA Forest Service

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

November is the time of year in Utah when the weather takes a quick turn from autumn to winter. As the line of snow from occasional October storms creeps further down the mountains, I’m inspired to bring wool sweaters and down jackets out of storage. It’s easy for us to simply wear extra layers, but what about the animals that live high in the mountains, where winter set in weeks ago?

While some mammals are cued by their internal clocks to begin sleeping the winter away, many brave creatures prepare to spend the winter searching for food. Being active in the cold requires a warmer coat, just like it does for us. The reduced amount of daylight in autumn triggers hormones that cue many mammals to grow a thicker and warmer fur coat.

Some mammals, such as weasels and hares, counter the onset of winter by ‘changing’ the color of their fur from brown to white. For instance, snowshoe hares grow long, white guard hairs that cover their brown fur in winter. The snowshoe hare benefits from this thicker, white fur not only by retaining heat, but also by using camouflage to hide from its many predators.

Surprisingly, white fur also helps insulate. It might make more sense for brown fur to be warmer since it is darker in color. But, white hairs, which lack the pigment melanin, have more air spaces that result in greater insulation.

While weasels are predators, there are other animals, including birds of prey, that feed upon them. The winter coat of the ermine, also referred to as the short-tailed weasel, is entirely white, except for the black tip of its tail. When an ermine runs, the tip of its tail swings wildly, drawing the attention of a predator away from its body to its expendable tail.

The timing of change from brown to white fur in autumn is critical to survival. An early snow can create a white backdrop for a snowshoe hare that is still brown, likely increasing the chance of predation. Conversely, a lack of snow late in autumn can make a snowshoe hare that has already turned white stand out like a sore thumb.

The number of days with snow on the ground has been decreasing in mountainous areas, and predation of snowshoe hares has been highest in spring and autumn. In some areas of the country, such as the Cascades and Olympic Mountains, snowshoe hares are mottled white and brown year round, or never turn white in winter. Comparing these populations to others across the West will help us better understand how animals, such as the snowshoe hare, are able to adapt to our changing climate.

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

Credits:

Images: Courtesy US NPS & USDA Forest Service
Text:     Mark Larese-Casanova, Utah Master Naturalist Program at Utah State University Extension.
Additional Reading:

University of Montana (2009, February 24). Climate Change Hurting Hares: White Snowshoe Hares Can’t Hide On Brown Earth. ScienceDaily. Retrieved November 22, 2011, from https://www.sciencedaily.com/releases/2009/02/090224220347.htm

Rust, C.C., R. M. Shackelford, and R.K. Meyer (1965). Control of Pelage Cycles in the Mink. Journal of Mammalogy, Vol. 46, No. 4 (Nov., 1965), pp. 549-565, https://www.ncbi.nlm.nih.gov/pubmed/5838224

Fraley, J. (2006). Snowshoe Hare: Lepus americanus. Montana Outdoors Portrait. Montana Fish, Wildlife, and Parks, https://fwp.mt.gov/mtoutdoors/HTML/articles/portraits/snowshoe.htm

 

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Why Do Birds Stand on One Leg?

Black-Necked Stilt
Himantopus mexicanus
Copyright © 2011 Holly Strand

Hi I’m Holly Strand.

On a recent Saturday my family and I visited Tracy Aviary in Salt Lake City. Walking through the wetland exhibit we saw a couple of black-necked stilts—a common Utah shorebird–snoozing near the boardwalk. They stood at the exhibit shoreline, each one balancing on a single, long, skinny, leg—the other leg drawn into the plumage underneath their bodies. Rotated almost 180 degrees, their heads and bills were tucked snugly under folded wings.

Why do birds choose to stand on just one leg? Wouldn’t it be more comfortable to distribute one’s weight on two? I’ve tried standing on one foot during yoga practice. It doesn’t feel like a good position for rest or sleep.

Over the years, several theories have emerged about this behavior in birds. One is that standing on one leg will reduce fatigue in the other leg. Then, if threatened, the bird could escape more quickly by using the rested leg to initiate motion.

Another theory is camouflage. Two parallel legs may look suspicious to ground level or aquatic prey. In contrast, one leg might resemble a reed or branch.

Perhaps the most common speculation is that birds are conserving heat via one-leggedness.

I wanted to test this last theory by standing barefoot in last weekend’s snow. First on one leg–and then on two for comparison. But I had a bad cold. I asked my biologist husband to do it for me, thinking he would be happy to support rational scientific thinking in the household. Alas, he rolled his eyes and made a noise that I’ve learned to translate as “You’ve got to be kidding me.”

Giving up on him, I dug deeper into the scientific literature.

At last I found a recent study conducted by Matthew Anderson and Sarah Williams of St. Joseph’s University. By observing Carribbean flamingoes these researchers showed that more birds stand on one foot at lower temperatures than at higher temperatures. Further, we know that loss of body heat to water is significantly greater than to air. So it would make sense to see more birds standing on one foot in the water than on land. And indeed this was the case. 80% of birds in water stood on one leg. On land, significantly less did so. Thus it does seem that temperature regulation is at least one reason for standing around on one leg.

In Utah look for one legged roosting among stilts, American avocets, night herons, double-breasted cormorants, and storks. Ducks, magpies and pigeons also stand on one foot for several minutes at a time
–it’s just harder to notice it in them because of their short legs.

For Wild About Utah, I’m Holly Strand.

Credits:

Table: Courtesy & Copyright © 2011 Holly Strand
Text: Holly Strand

Sources & Additional Reading:

Anderson, Mathew and Sarah A. Williams. 2010. Why do flamingos stand on one leg? Zoo Biology. Volume 29, Issue 3, pages 365–374, May/June 2010

Clark Jr., GA. 1973. Unipedal postures in birds. Bird-Banding, 44:22–26.

Tracy Aviary in Salt Lake City https://www.tracyaviary.org/

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Nature’s Recyclers

Fungi Decomposing Fall
Leaves Outside the
Stokes Nature Center
Courtesy & © 2011 Andrea Liberatore
Stokes Nature Center


Redworms Eisenia fetida
from Stokes Nature Center’s
vermicomposting system
Courtesy & © 2011 Andrea Liberatore
Stokes Nature Center

On Tuesday, November 15th, our nation celebrates America Recycles Day. While the day itself tends to focus on human recycling activity, I thought we should also give a nod to nature’s recyclers. Worms, maggots, fungi, beetles, and bacteria – it sounds like a list of leftover Halloween horrors. But in reality, we should be more afraid of what our world would look like without these creepy-crawlies, for these are nature’s recyclers. Scientists call these organisms saprophytes, and as important as their role in life is, they are more likely to evoke a shudder than any feeling of gratitude.

What decomposers actually do is break dead things down into smaller and smaller pieces, until all that is left are the basic molecular components that make up all living things such as nitrogen, phosphorous, carbon, and potassium. Once broken down, this material is then free to be taken up again by plants and animals that use them to live and grow. This cycle of nutrients is vital to life on Earth, and our saprophytic friends make it all possible.

While decomposition would occur even without the help of the decomposers, it would take much, much longer. In some landfills, newspapers have been unearthed that are more than 20 years old, and still quite readable. This is because landfills often create anaerobic environments, where oxygen-loving insects, fungi, and bacteria cannot live and therefore cannot aid decomposition. If without decomposers, a newspaper can last 20 years, what would happen to much larger and hardier items such as tree trunks and roadkill? I shudder to think about it.

Did you know that the U.S. throws more than 33 million tons of food waste into landfills each year? This organic material goes to waste there – taking up valuable space and taking longer than normal break down. So this year, celebrate America Recycles Day by employing some of nature’s recyclers in your yard. Consider starting a compost pile where your fall leaves and food scraps can get broken down into nutrient-rich all-natural fertilizer for next year’s garden.

If you’re in Cache Valley and are looking for a way to mark America Recycles Day, please join the Stokes Nature Center for a tour of the Logan landfill to find out what happens to your garbage and how recycling programs ensure there is less of it. This free tour will be held at 4:30pm on Tuesday, November 15th. For details, visit the Stokes Nature Center website at www.logannature.org.

For composting tips and more information about nature’s recyclers, visit Wild About Utah online at www.wildaboututah.org. Thank you to the Rocky Mountain Power Foundation for the research and development of this Wild About Utah topic. For the Stokes Nature Center and Wild About Utah, this is Andrea Liberatore.

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

Credits:

Photos: Courtesy & © 2011 Andrea Liberatore, https://logannature.org/
Text:    Andrea Liberatore, Stokes Nature Center, logannature.org

Composting Tips & Information:

Farrell-Poe, K. and Koenig, R. (2010) Backyard Composting in Utah. Utah State University Cooperative Extension. https://extension.usu.edu/files/publications/factsheet/HG-Compost-01.pdf

U.S. Environmental Protection Agency: Composting. https://www.epa.gov/epawaste/conserve/rrr/composting/index.htm

Additional Reading:

Fogel, R. (2002) Waste Not, Want Not: Fungi as Decomposers. Utah State University Herbarium. https://utahpests.usu.edu/ipm/ornamental-pest-guide/diseases/wood-decay-fungi

Hoff, M. (2009) Young Naturalists: Nature’s Recyclers. Minnesota Conservation Volunteer Newsletter. July-August 2009. https://files.dnr.state.mn.us/publications/volunteer/young_naturalists/natures_recyclers/natures_recyclers.pdf

U.S. Environmental Protection Agency (2011) Basic Information About Food Waste. https://www.epa.gov/osw/conserve/materials/organics/food/fd-basic.htm

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Lewis and Clark’s Taxonomic Legacy

Clark’s Nutcracker
Courtesy US FWS
Dave Menke, Photographer
Lewis’s Woodpecker
Courtesy US FWS
Dave Menke, Photographer

Thomas Jefferson will forever be remembered as our third president and author of the Declaration of Independence. Jefferson oversaw the acquisition of the vast Louisiana Purchase and soon thereafter initiated planning for an expedition that would be named the “Corps of Discovery”. That bold adventure was led by Meriwether Lewis and William Clark. These two frontiersmen are immortalized by the plants and animals that taxonomists named in their honor.

The arduous 3-year expedition route passed far north of what would become Utah, ascending the tributaries of the Missouri River and later following down the Columbia River to the Pacific Ocean. Jefferson, being an avid naturalist, instructed the explorers to observe and make record of the geography, plants and animals that they encountered and to return with those specimens which they could carry. Hopes for discovery of a navigable inland passage to the Pacific were not realized, but in all other ways, the expedition was a singular success.

Lewis and Clark made collections of pressed plants along the way. These eventually went to Frederick Pursh, a German botanist in Philadelphia. One new genus of plant he named Lewisia. These are the bitteroots, one of which is the spectacular state flower of Montana. Another genus new to science he named Clarkia . Many species names of plants immortalize the men too, such as the blue-flowered flax, Linum lewisii, commonly used today for seeding following wildfire.

Bird names honoring the discoveries of Lewis and Clark include Clark’s nutcracker and Lewis’ woodpecker. Clark’s nutcracker is a big black and gray relative of crows. [https://wildstore.wildsanctuary.com/collections/special-collections, https://wildstore.wildsanctuary.com/collections/special-collections] This noisy resident of Utah’s mountains is notable for its habit of caching seeds of pine trees to be remembered and found months later.

The age of the pioneer naturalist in North America closed more than a century ago, but the names of men like Meriwether Lewis and William Clark live on with the plants and animals that bear their names.

This is Linda Kervin for Bridgerland Audubon Society.

Credits:

Images: Courtesy US FWS images.fws.gov
Audio: Courtesy & Copyright https://wildstore.wildsanctuary.com/collections/special-collections, https://wildstore.wildsanctuary.com/collections/special-collections
Text: Jim Cane, Bridgerland Audubon Society

Additional Reading:

The Lewis and Clark Herbarium, Images of the Plants Collected by Meriwether Lewis and William Clark, 1804-1806, Presented by the University of Maryland and The Academy of Natural Sciences in Philadelphia in cooperation with Cornell University, https://www.plantsystematics.org/reveal/pbio/LnC/LnCpublic.html

Evans, Howard Ensign. 1993. Pioneer naturalists: the discovery and naming of North American plants and animals. Henry Holt & Company, New York. Illustrated by Michael G. Kippenhan. ISBN: 0-8050-2337-2, https://www.amazon.com/Pioneer-Naturalists-Discovery-American-Animals/dp/0805023372

And for a thorough treatment of Clark’s nutcracker:

https://en.wikipedia.org/wiki/Clark%27s_Nutcracker

All About Birds, The Cornell Lab of Ornithology:

https://www.allaboutbirds.org/guide/lewiss_woodpecker/id

https://www.allaboutbirds.org/guide/Clarks_Nutcracker/id