Category: Reptiles

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A Rocky Relationship with the Desert

Chuckwalla Lizard Basking
Copyright 2010 Cameron Rognan

On a recent trip to the Red Cliffs Desert Reserve in St. George, I learned about a creature with an amazing sense of place. The chuckwalla is a large member of the lizard family which resides in the desert southwest, an area well known for its temperature extremes. Like many other desert dwelling creatures, the chuckwalla has evolved a unique set of adaptations that enable it to thrive in its environment.

Chuckwallas live almost exclusively in rocky areas, and these rocks are the key to their survival. As cold-blooded creatures, they cannot regulate their own temperature, and instead rely on the environment to warm and cool their bodies. The chuckwalla’s flat body shape allows it to warm rapidly on a cool morning by pressing itself tightly to a rock in the sun. This behavior also allows it to quite literally keep a ‘low profile’ from predators. Another temperature control adaptation involves the chuckwalla’s color. While individuals exhibit regional variations from black to brown to yellow, they also have the ability to adjust their skin color to best absorb or reflect sunlight and therefore help regulate their body temperature. During the day, temperatures often soar higher than a chuckwalla can handle, and the lizards retire to the cool shade of the rocks.

Chuckwalla Lizard in a Crevice
Copyright 2010 Cameron Rognan

Apart from helping chuckwallas maintain their temperature, rocks also play a key role in the lizard’s defense against predators, including coyotes and birds of prey. When threatened, a chuckwalla will retreat to the nearest crack or crevice and take in large gulps of air. These big breaths inflate the chuckwalla’s chest cavity like a balloon, wedging its body tightly to the rocks around it – a brilliant move which makes the lizard nearly impossible to pull out by force. Most predators will soon give up and move on to find an easier meal. This behavior gives a whole new meaning to the chuckwalla’s ability to ‘fit’ its environment.

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

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

Chuckwalla Lizard
Copyright 2010 Cameron Rognan

Credits:

Photos: Courtesy & Copyright Cameron Rognan
Text: Andrea Liberatore, Stokes Nature Center
Additional Reading:

Stebbins, Robert C. 2003. Peterson Field Guides: Western Reptiles and Amphibians, Third Edition. New York: Houghton Mifflin Company., https://www.amazon.com/gp/product/0395982723

Arizona-Sonora Desert Museum, “Reptile and Amphibian Accounts: Chuckwalla” (Sauromalus obesus) https://www.desertmuseum.org/books/nhsd_chuckwalla.php (Accessed Nov 22, 2010)

Cooper, W.J. et al, 2000. Lizard Antipreditory Behaviors Preventing Extraction from Crevices. Herpetologica, 56(3): 394-401

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Species Names

Common Mullein
Courtesy &
Copyright 2010 Holly Strand

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

Common Mullein , Our Lady’s Flannel. Velvet Plant. Clown’s Lungwort. Jupiter’s Staff. Shepherd’s Clubs. Beggar’s Blanket. Hare’s Beard, Bear’s ear, and Nature’s Toilet Paper. These are just a few of the names that apply to a single species that is a widely distributed across Europe and Central Asia and naturalized in North America.

Common names are descriptive and often charming, but they are local names and won’t be understood beyond their particular region or in another language. And sometimes common names are downright misleading. For example a koala bear isn’t a bear. And a red panda isn’t a panda.

To avoid confusion, scientists use a unique two word designation—usually taken from Latin or Greek – to identify a species unambiguously. The first word is the name of the genus to which the organism belongs. The genus comprises a group of closely related animals or plants. The second term is chosen by the person that describes and publishes the species account.

Vampyroteuthis infernalis
“vampire squid from Hell”
Illustration by Carl Chun 1911
Public Domain/expired copyright

It is a huge breach of etiquette to name a species after yourself. But the taxonomist can name the organism after the person who actually found it in the field. An example is Mentzelia shultziorum, a blazingstar named after Utah botanist Leila Schultz who first found the plant in Professor Valley in Grand County. Taxonomists can also name the species after a friendly colleague and then hope that the friendly colleague will name one after them.

Often the name will describe some physical characteristics of the species. Earlier this year, a paleontologist unearthed a new dinosaur here in Utah and named it Jeyawati rugoculus. That’s a combination of Zuni and Latin for “grinding mouth, wrinkle eye.”

Other names are based on location: Penstemon utahensis is a penstemon found in our state. Amblyoproctus boondocksius is a scarab, and was apparently found in the middle of nowhere.

Often the name will represent a subjective reaction toward the organism. Vampyroteuthis infernalis translates into “vampire squid from Hell”, Indeed it is rather scary looking cross between a squid and an octopus.

Some scientists get sentimental at naming time. They’ll name species after their loved ones. Or their favorite artists. Thus we have 2 trilobites in the Avalanchurus genus named lennoni and starri. McCartney and Harrison are honored in a neighboring genus.

I’m proud to say that a Utah biologist named a parasitic louse, Strigiphilus garylarsoni. The Far Side cartoonist should not take offense. In a letter to Larson, Dr. Dale Clayton praised him for “the enormous contribution that my colleagues and I feel you have made to biology through your cartoons.”

For sources and archives of past programs see www. Wild About Utah.org

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

Credits:
Photo: Mullein-Courtesy & Copyright 2010 Holly Strand
Squid Illustration Carl Chun 1911 (Public Domain Courtesy Wikimedia.org)
Text: Stokes Nature Center: Holly Strand

Sources & Additional Reading

Gotch, A.F. 1996. Latin Names Explained: A Guide to the Scientific Classification of Reptiles, Birds & Mammals. NY: Facts on File, Inc.

Isaak, Mark. Curiosities of Biological Nomenclature website. https://www.curioustaxonomy.net/rules.html [Accessed September 15, 2010]

O’Donoghue, Amy Joi. 2010. ‘Grinding mouth, wrinkle eye’ is name of newly discovered species dinosaur. Deseret News, May 27, 2010.

Prigge, Barry A. 1986. New Species of mentzelia (Loasaceae) from Grand County, UT. Great Basin Naturalist Vol. 46, No. 2 pp. 361-365

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Rattlesnakes

Great Basin Rattlesnake
Courtesy & Copyright 2009
Holly Strand
Hi, I’m Holly Strand from Stokes Nature Center in beautiful Logan Canyon.

Its rattlesnake season in Utah, for the warm weather draws them out of their dens. We have 5 species plus 2 subspecies of rattlesnake in the state. The Great basin rattlesnake is the most widespread, living all across Western Utah at elevations up to 9000 feet. This is the fellow you see around Logan. Another subspecies of western rattler–the midget faded rattlesnake –is dominant in the eastern part of the state. The Hopi rattlesnake and the greenish colored prairie rattlesnake are found in southwestern Utah. And the Mojave rattlesnake, speckled rattlesnake, and sidewinder are found only in the extreme southwest corner of Utah.

The rattle itself is a unique biological feature. It’s a loose, but interlocking series of nested segments—actually modified scales– at the end of the tail. When vibrated, the rattle produces a hissing sound. Kevin Colver– an expert in natural sound recordings –provided this clip of a Mojave rattlesnake. Sound from Westernsoundscape.org Hmm. wouldn’t that make a great ringtone?

Aggression and venom in rattlesnakes vary by both species type and by individual. The western diamondback rattlesnake is the archetypal large, aggressive and very dangerous species, responsible for the majority of human fatalities. But its northern range limit is south of the Utah border. However, the Mojave rattler found in southeastern Utah is extremely toxic and excitable. Its venom attacks both the nervous system and circulatory system.

Luckily, rattlesnakes aren’t out to get us—mainly they just want to be left alone. You’ll be fine if you stay aware of what might be lurking in or around rocks. And don’t walk barefoot or in open-toed shoes in their habitat. Also, use a flashlight after dark –most rattlesnakes are active at night too!

Thanks to the Marie Eccles Caine Foundation—the Russell family for supporting Stokes Nature Center programs. And to Kevin Colver for the sound of the rattlesnake. Additional nature sound recordings can be found at 7loons.com and westernsoundscape.org

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

Credits:

Theme: Courtesy & Copyright Don Anderson Leaping Lulu
Audio:     Courtesy & Copyright 2006 Kevin Colver, https://wildstore.wildsanctuary.com/collections/special-collections & Jeff Rice, Stokes Nature Center
Text:     Holly Strand, Stokes Nature Center
Voice: Holly Strand, Stokes Nature Center

Sources & Additional Reading:

Klauber, Laurence M. 1982. Rattlesnakes. Their Habits, Life Histories, and Influence on Mankind. Berkeley: University of California Press, https://www.amazon.com/Rattlesnakes-Habits-Histories-Influence-Mankind/dp/0520210565 (1997 Version)

Vipers, Species, Utah Division of Wildlife Resources, Utah Division of Natural Resources, https://fieldguide.wildlife.utah.gov/?family=viperidae [Updated January 2024]

Tips to stay safe around rattlesnakes, Utah Division of Wildlife Resources, Utah Department of Natural Resources, https://wildlife.utah.gov/news/utah-wildlife-news/943-rattlesnakes-safety-tips.html [Updated January 2024]

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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