Beavers: The Original Army Corps of Engineers

Beaver with branch in water
Courtesy US FWS,
Steve Hillebrand, Photographer


Hi, I’m Holly Strand from Stokes Nature Center in beautiful Logan Canyon.

Beavers and beaver dams are a common feature of the Utah landscape. You’ll see the dams on smaller streams and side channels, constructed of branches, downed trees and mud. The still, deep water of the resulting pond creates ideal conditions for a beaver lodge. Beavers can escape and hide from predators by slipping into the pond and disappearing into the lodge. Beavers also use their ponds to cache their favorite
food—aspen and willow.

Because of their tree cutting and dam making skills, humans tend to have two divergent opinions of beavers: 60-pound nuisance or environmental engineer.

Beaver lodge
Courtesy US FWS
Hans Stuart, Photographer

Beavers are considered a nuisance when they gnaw down trees that humans want to keep. Dams can flood roads or stop up irrigation canals. When beaver activity conflicts with human interests, they—the beavers–are likely to be trapped and killed.

However, beaver activity has many positive environmental consequences that we are just beginning to appreciate. Wetlands created by beaver dams help soak up sediments, improving downstream water quality. Because of beaver dams, the winter snowpack isn’t lost in a short spring pulse, This results in a more constant stream flow through the summer –and that’s important as Utah’s climate is predicted to become drier. Finally, beaver dams enhance habitat for many other fish and wildlife species and plants.

Beaver in pond
Courtesy US FWS
Steve Hillebrand, Photographer

According to Dr. Joe Wheaton, a geomorphologist at Utah State University, there’s a lot of untapped potential for employing beaver engineers in stream and floodplain restoration. Say you want to restore a stream by reconnecting it with its floodplain. You need to excavate channels, redirect stream flow, revegetate and nurture the
area for a long period of time. To accomplish this, you often need a
number of highly trained professionals and some large Tonka toys.

Alternatively –under the right conditions– you might transplant a
colony of beavers and let them apply their vigorous work ethic to your
landscape and get quite satisfying results.

Recognizing that nuisance beavers can be rehabilitated into hard
working wetland engineers and stream habitat restorationists, the Utah
Division of Wildlife Resources has rolled out the state’s first beaver
management plan in 2010. This plan encourages live trapping of entire
families of beavers in nuisance areas and moves them to specific sites where their
environmental services can be appreciated and put to use.

Beaver in snow
Courtesy US FWS

Thanks to the USU College of Natural Resources for supporting this Wild about Utah topic.

For Wild About Utah and Stokes Nature Center, I’m Holly Strand.

Credits:
Images: Courtesy US FWS, Photographers: Steve Hillebrand and Hans Stuart, https://images.fws.gov
Text: Holly Strand, Stokes Nature Center

Sources & Additional Reading

Collen, P. and R.J. Gibson. 2001. The general ecology of beavers (Castor spp.), as related to their influence on stream ecosystems and riparian habitats, and the subsequent effects on fish – a review. Reviews in Fish Biology and Fisheries 10: 439–461, 2001. https://web.archive.org/web/20230202160926/https://www.researchgate.net/publication/227028536_The_general_ecology_of_beavers_Castor_spp_as_related_to_their_influence_on_stream_ecosystems_and_riparian_habitats_and_the_subsequent_effects_on_fish_-_A_review [ Accessed May 1, 2010]

Prettyman, B. 2009. Utah wildlife: Leave it to the beavers. Article in Salt Lake Tribune, October 16, 2009. https://www.sltrib.com/ci_13570110 [ Accessed April 29, 2010]

Smithsonian Castor Canadensis Information Page https://www.mnh.si.edu/mna/image_info.cfm?species_id=32 [ Accessed April 29, 2010]

Big Bend Habitat Restoration Project: A Natural Work of Heart, Open Spaces-A Talk on the Wild Side, US FWS, https://www.fws.gov/news/blog/index.cfm/2016/3/25/Big-Bend-Habitat-Restoration-Project-A-Natural-Work-of-Heart [Accessed March 31, 2016]

Beaver Dams Strengthened by Humans Help Fish Rebound
60-Second Science – July 25, 2016 – By Jason G. Goldman02:29 https://www.scientificamerican.com/podcast/episode/beaver-dams-strengthened-by-humans-help-fish-rebound/ Also available through the podcast https://itunes.apple.com/us/podcast/60-second-science/id189330872?mt=2

Restoring Degraded Waters, One Pest at a Time, Utah State Magazine, Utah State University, December 7, 2021, https://utahstatemagazine.usu.edu/environment/restoring-degraded-waters-one-nuisance-at-a-time/

Goldfarb, Ben, Eager: The Surprising, Secret Life of Beavers and Why They Matter, Chelsea Green Publishing, March 8, 2019, https://www.amazon.com/Eager-Surprising-Secret-Beavers-Matter/dp/1603589082/ref=asc_df_1603589082/

American Pronghorn

American Pronghorn Buck
Courtesy US FWS Digital Library
Photographer: James C. Leopold

Hi, I’m Holly Strand from Stokes Nature Center in beautiful Logan Canyon.

The American pronghorn has an identity problem. It’s Latin name Antilocapra Americana means “American antelope goat.” But the fleet-footed animal of the American West is neither an antelope nor a goat. It is the sole survivor of a family of hooved animals that flourished in the Miocene, from 7-25 million years ago. More than 13 species of that family have been found in the fossil record, but only one pronghorn survived to modern times. 
 

American Pronghorn DoePhotographer: James C. Leopold Courtesy US FWS Digital Library

Many consider the pronghorn to be the fastest land animal in the world. Certain individuals have been clocked up to 60 miles an hour. It’s true that cheetah can go 70 miles per hour,–but only for several hundred yards. The pronghorn on the other hand, can go for great distances at high speed without breaking a sweat, leaving pursuers such as coyotes and wolves in the dust. Mountain lions occasionally creep up behind them, but that’s tricky in the open grasslands and shrub steppe that pronghorns prefer. Simply put, no land mammal on earth can keep up with the pronghorn over a significant distance.

Pronghorn Herd RunningCourtesy US FWS Digital Library
Photographer: Jack Woody

So why is this animal so implausibly fast? John Byers of the University of Idaho believes that the pronghorn and its relatives evolved traits to enhance speed under the influence of ghost predators. These predators are now extinct but their existence is memorialized through the adapted traits of their prey.

Before the late Pleistocene extinction, a variety of carnivorous megafauna filled grasslands often referred to as the American Serengeti. The giant short-faced bear, the American lion, a jaguar, a form of hyena and the saber-toothed cat were likely ambush predators of the pronghorn. But the most compelling reason for the pronghorn’s improbable speed is the presence of the North American cheetah. This long -limbed cat with powerful heart and lung capacity set off an evolutionary arms race with the pronghorn. Natural selection favored speed since slow cats went hungry and slow pronghorns were devoured.

American Pronghorn BuckCourtesy US FWS Digital Library
Photographer: Harvey Doerksen
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Nowadays, lacking the need for such swift getaways, it’s possible that the pronghorn has slowed down. But if slowing down is 60 miles an hour, imagine what a high speed chase with the powerful prehistoric cheetah must have been like!

For Wild About Utah and Stokes Nature Center, I’m Holly Strand.
Credits:
Images: Courtesy US FWS Digital Library
Text:     Holly Strand, Stokes Nature Center
Sources & Additional Reading:

Adams, Daniel B. 1979, “The Cheetah: Native American” Science 205 (4411): 1155–1158. https://www.sciencemag.org/cgi/content/abstract/205/4411/1155

John A. Byers, American Pronghorn: Social Adaptations and the Ghosts of Predators Past, University of Chicago Press, 1998, https://www.amazon.com/American-Pronghorn-Social-Adaptations-Predators/dp/0226086992

John A. Byers, Built for Speed: A Year in the Life of Pronghorn, Harvard University Press, 2003, https://www.amazon.com/Built-Speed-Year-Life-Pronghorn/dp/0674011422

Pronghorn, ANTILOCAPRA AMERICANA, Utah Conservation Data Center, Utah Division of Wildlife Resources, https://dwrcdc.nr.utah.gov/rsgis2/Search/Display.asp?FlNm=antiamer

Pronghorn, Wildlife Library, National Wildlife Foundation, https://www.nwf.org/Wildlife/Wildlife-Library/Mammals/Pronghorn.aspx

Antilocapra americana, Pronghorn, Animal Diversity Web, University of Michigan Museum of Zoology, https://animaldiversity.org/accounts/Antilocapra_americana/

 

Censuses and Surveys

Wolf with Radio Collar watches biologists FWS Digital Library, Photo by William Campbell
Wolf with Radio Collar
Photographer: William Campbell
US FWS

Hi, I’m Holly Strand from Stokes Nature Center in beautiful Logan Canyon.

This year’s Census is the 23rd national headcount in United States history.

Census results affect the allocation of all kinds of government financial and program resources. The Census also determines the distribution of seats in
the state and federal House of Representatives.

It is also important to know the number and whereabouts of different wildlife species. This information is used for a number of management purposes– for instance, monitoring the status of endangered species or determining hunting or fishing quotas.

Mountain Lion with Radio Collar
Photographer: Claire Dobert
Courtesy US FWS

Counting wildlife isn’t as easy as counting people. You can’t mail
animals a survey with a self-addressed stamped envelope and you don’t necessarily know where to find them at any given point in time.

True censuses of animals are rare for in most cases a complete count is either too expensive or too difficult to undertake. Only animals conveniently and visibly grouped in a particular location can be censused– such as fish in a fish hatchery, or large animals along a certain migration route.

Setting a waterfowl capture net
Courtesy US FWS

Instead, biologists define an area of interest, then sample at random locations within that area. Samples usually consist of a number of transects or randomly selected quadrants. Counts from these samples are then extrapolated to an entire habitat or study area.

Along with selecting a sampling method, you have to figure out how you are going to effectively count an individual occurrence. This can be extremely tricky. Especially if your animal is reclusive or nocturnal. According to Dr. Eric Gese, a specialist in predator ecology at Utah State University, biologists use tracks, scats, scratches, burrows, hair samples –even roadkill counts as proxies for individual animals.

FWS Biologist Tracking a Black Bear
Photo by John & Karen Hollingsworth,
Courtesy US FWS

Capturing, marking and recapturing animals is one of the most reliable–albeit expensive– ways to do a direct count of animals. Captured animals are marked with ear tags, radio collars, dyes or even radioactive isotopes. In a future program I’ll describe an example of how one scientist tracks and counts large and elusive predators in the wild.

Thanks to Utah State University’s College of Natural Resources for supporting the development of this Wild About Utah topic.

For Wild About Utah and Stokes Nature Center, I’m Holly Strand.
Credits:
Images: Courtesy US FWS Digital Library
Text:     Holly Strand, Stokes Nature Center
Sources & Additional Reading:

Gese, E. M. 2001. Monitoring of terrestrial carnivore populations. Pages 372–396 in J. L. Gittleman, S. M. Funk, D. Macdonald, and R. K. Wayne, editors., Carnivore conservation. Cambridge University, Cambridge, United Kingdom.

Video: Biologists track hibernating bears for research, KSL Broadcasting Salt Lake City UT, 27 March 2010, https://www.ksl.com/index.php?nid=647&sid=10166167

American Black Bear, Utah Division of Wildlife Resources, wildlife.utah.gov/publications/pdf/bearnew.pdf

(tracking) Black-footed Ferrets, Wildlife Review Utah Division of Wildlife Resources, wildlife.utah.gov/wr/0804ferrets/0804ferrets.pdf

 

Mountain Lion

Mountain Lion
Courtesy USDA

Hi, I’m Holly Strand from Stokes Nature Center in beautiful Logan Canyon.

One cold dawn in January I glanced out the kitchen window at the snow-covered yard. Something moved and my eyes focused on a large dog-sized animal half hidden and crouched behind some rabbit brush. Funny I thought. I’ve never seen a large dog like that in this neighborhood. I continued to watch the backyard visitor but it was very still and hard to see. I raced upstairs to get a better view from the second floor window. As I reached the window I got a brief glimpse of the animal as it melted away into a large ravine. It was definitely not a dog. Dogs don’t “melt” as a method of locomotion.

Courtesy US FWS Digital Library

Given the size, the color, the time of day, and the way it moved, I’m pretty sure that I saw a mountain lion. In winter our yard is a mountain lion pantry, plentifully stocked with live mule deer steaks browsing on our trees. Undoubtedly that’s what attracted my morning visitor.

The mountain lion, or cougar as it is often called, was once the most widely distributed mammal in the Americas. Nowadays, In the United States, it is now mainly restricted to remote areas in the western part of the country including in Utah. According to the Division of Wildlife Resources, the only place in Utah they’re not found is in the salt flats west of the Great Salt Lake.

Photographer: Larry Moats
Courtesy US FWS Digital Library

Although they are found everywhere in the state, the animals are rarely seen. They are extremely secretive and largely nocturnal. They usually know where you are before you know where they are, so they can easily avoid human contact .

Mountain lion attacks are extremely rare and there have been no deaths from them in Utah. Nevertheless, they can kill people and with wildlife-human confrontations on the increase it’s good to know what to do if you meet one of these big kitties. First of all, don’t run from or turn your back to a mountain lion. Its instinct is to chase running animals. Make yourself look as big as possible by raising your arms up high. Speak loudly and fight back if attacked. If you live near mountains or rocky cliff areas keep a close eye on children and pets especially at dusk and dawn.

Photographer: Claire Dobert
Courtesy US FWS Digital Library

Thanks to the Rocky Mountain Power Foundation for supporting the development of this Wild About Utah program.

For Wild About Utah and Stokes Nature Center, I’m Holly Strand.
Credits:

Images: Courtesy USDA and US FWS Digital Library

Text:     Holly Strand, Stokes Nature Center

Sources & Additional Reading:

Mountain Lion, Wildlife Notebook, Utah Division of Wildlife Resources, https://wildlife.utah.gov/publications/pdf/newlion.pdf

Starving Cougar Attacks Vernal Man, Hans Moran, Deseret News Nov. 12, 1997, https://www.deseretnews.com/article/594408/Starving-cougar-attacks-Vernal-man.html

Mountain Lion, National Geographic, https://animals.nationalgeographic.com/animals/mammals/mountain-lion.html