Vertebrates Archives - Page 102 of 122

October 20, 2011July 18, 2020

Desert Animals-Extreme Survivors

Click to view larger image of Kangaroo Rat, Photo Courtesy US FWS, George Harrison, Photographer — Collared lizard
Photo Courtesy US FWS
Lawrence Gamble, Photographer

Kangaroo Rat
Photo Courtesy US FWS
George Harrison, Photographer

Gila Monster
Photo Courtesy & © Daniel D. Beck
Central Washington University

Couch’s Spadefoot Toad
Photo Courtesy US FWS
Gary M. Stolz, Photographer

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

The three main deserts of Utah- the Great Basin to the west, the Colorado Plateau to the east, and the Mojave Desert in the southwest corner of the state- are each inhabited by animals that have unique adaptations for surviving the extreme heat, dryness, and sometimes cold temperatures of the desert.

Many animals survive in Utah’s deserts through behavioral adaptations. During the heat of the day, most animals can be found underground in burrows, or simply sitting in the shade of a shrub or tree. Reptiles, such as the desert tortoise and gila monster, spend almost all of their time in a burrow or under a rock. Many birds and mammals are most active near dawn and dusk when temperatures are coolest, yet there is enough light to see. Many bats, snakes, and rodents are nocturnal, and are only active at night!

Morphological adaptations, related to the shape or color of an animal’s body, are also important for living in the desert. The collared lizard has long legs and toes that keep its body away from the hot ground, reducing heat absorption. White-tailed antelope ground squirrels will use their bushy tails as a shade umbrella, and the long ears of the jackrabbit aid in dispersing body heat.

The kangaroo rat has perhaps the most amazing combination of adaptations for desert survival. Not only does it live in a burrow and is nocturnal, but it recaptures it’s own body moisture by storing food within its burrow. Dry seeds absorb moisture from the kangaroo rat’s breath, which condenses more readily in the cooler underground temperatures.

Physiological adaptations relate to a change in body function to aid survival in the desert. The kangaroo rat has such complex kidneys that it is able to retain as much water as possible. It also has specialized tissues in its nasal passages that help it retain much of the moisture that is normally lost through breathing. If the desert gets too hot, many animals will aestivate, which is similar to hibernating, but is usually in response to a lack of water rather than a lack of food. The spadefoot toad spends 10-11 months out of the year buried in the soil, only to emerge to breed and feed during summer rainstorms.

So, while at first glance, it may look like there isn’t much life in the desert, keep in mind that the vast array of adaptations help ensure the survival of a high diversity of plants and animals in such a harsh ecosystem.

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

Credits:
Images: Courtesy US FWS images.fws.gov
Courtesy & Copyright Daniel D. Beck, Central Washington University
Text: Mark Larese-Casanova, Utah Master Naturalist Program at Utah State University Extension.

Additional Reading:

Utah’s Desert Dwellers: Living in a Land of Climate Extremes. Wildlife Review. Utah Division of Wildlife Resources
wildlife.utah.gov/wr/0706desert/0706desert.pdf

Deserts. James MacMahon. The Audubon Society Nature guides. 1985. https://www.amazon.com/Deserts-National-Audubon-Society-Nature/dp/0394731395

Natural History of the Colorado Plateau and Great Basin, Harper, St. Clair, Thorne, and Hess (Eds.), 1994. https://www.amazon.com/Natural-History-Colorado-Plateau-Great/dp/0870815113

The Biology of Deserts, David Ward, Oxford University Press, 2009. https://www.amazon.com/Biology-Deserts-Habitats/dp/0199211477

September 29, 2011March 4, 2026

Migratory Birds and Coffee

Western Tanager, click to view larger image, Photo Courtesy and Copyright © 2010 Michael Fish — Western Tanager
Courtesy & Copyright © 2010
Michael Fish

For many of us, the day has not truly begun until we hold a warm mug of richly flavored coffee in our hands. But how often have you considered where that coffee comes from and how its culture impacts wild Utah?

We tend to think of migratory birds as our residents who take a winter vacation to the south every year. But it is more truly the other way around. They are representatives from groups of tropical birds who venture north to take advantage of less crowded nesting and a seasonal abundance of food for their young. For instance, of the 49 species of true tanagers, only 4 summer in the United States. Much of our coffee originates in Central and South America and its production directly affects birds who fly north to nest in Utah.

Traditionally, coffee bushes are grown under a diverse canopy. Some of the trees in the overstory yield timber, others fix nitrogen and still others like papaya provide food. This multi-tiered habitat supports a wide variety of birds that is only exceeded by undisturbed tropical forest itself.

About twenty years ago, coffee production changed radically with the development of varieties that tolerate full sun. This has allowed huge areas of land to be cleared of forest and planted exclusively to row after row of coffee bushes that demand intensive management. More fertilizer and pesticides are needed leading to toxic runoff. Soil erosion increases. Much lovely bird habitat has been destroyed for this barren coffee monoculture. Many migratory bird populations are in trouble due to the loss of their forested winter habitats.

But there is hope for coffee lovers because many farmers still grow coffee in the traditional way. These grower-owned farms tend to be smaller and provide a more reliable income for the farmer due to the diversity of crops. Soil quality is maintained while providing critical habitat for tropical frogs, insects, plants and birds. When purchasing coffee, look for bird friendly or shade grown or certification by Rainforest Alliance or Smithsonian. Our warblers, tanagers and thrushes will thank you.

This is Linda Kervin for Bridgerland Audubon Society.

Credits:

Images: Courtesy & Copyright Michael Fish
Text: Linda Kervin, Bridgerland Audubon Society

Additional Reading:

Shade-Grown Coffee, National Audubon Website, https://web4.audubon.org/bird/at_home/coffee/

Song Bird Coffee, American Birding Association, https://www.aba.org/shadecoffee/songbird.html

Some Coffee-related Resources, American Birding Association, https://www.aba.org/shadecoffee/whattodo.html#Coffee-related%20Resources

Why Migratory Birds are Crazy for Coffee, Migrants and Coffee: What’s the Connection?, National Zoo, Smithsonian Institution, https://nationalzoo.si.edu/scbi/MigratoryBirds/Fact_Sheets/default.cfm?fxsht=1

Why Migratory Birds Are Crazy for Coffee, Atlanta Audubon Society, formerly: https://atlantaaudubon.org/aaswww/sgc/sgcfacts.htm

Smithsonian-Certified Shade Grown & Bird Friendly Coffee, Caffe Ibis, https://caffeibis.com/

September 15, 2011February 12, 2026

Crow vs. Raven

Image of the American Crow, Corvus brachythynchosby, Courtesy and Copyright 2011 Wayne Whaley — Common Raven (Corvus corax)
Bryce Canyon National Park
Courtesy US National Park Service
And found on Wikipedia

American Crow Juvenile & Parent
*(Corvus brachythynchosby)*
Copyright © 2011 Wayne Whaley

American Crow, Orem, UT
*(Corvus brachythynchosby)*
Copyright © 2011 Wayne Whaley

American Crow Pair, Orem, UT
*(Corvus brachythynchosby)*
Copyright © 2011 Wayne Whaley

Hi I’m Holly Strand.

As you might have guessed, the American crow and the common raven are birds of a feather—two closely related species of the same genus Corvus. Both of them are residents of Utah. Together with family members magpies and jays, crows and ravens are among the brainiest animals on the planet.

Many times I’ve heard someone ask “Is that a crow or a raven?” or “What’s the difference between them?”

Perhaps the easiest way to tell these two apart is by size. If you are thinking to yourself “Wow! That’s a huge crow!” You are probably looking at a raven. Ravens can weigh over 2.5 pounds while crows typically weigh less than 1. The Raven’s wingspan can clear 4.5 feet while that of crows is less than 3. Proportional to their bodies, the bill on a Raven is larger and thicker.
The crow has a thinner, more pointed bill.

Take a look at the tail in flight: a crow tail is fan shaped with a straight tail edge. A raven tail has a rounded wedge shape.

In the air, ravens usually soar, while crows will flap a lot more. It’s not always apparent why, but some ravens will perform acrobatic rolls during flight—usually half rolls, but sometimes full rolls and even double rolls!

Common ravens are abundant throughout Utah, They can be found in almost all habitats and in all seasons. They are more wilderness-oriented than crows who prefer forest edges, savannas, agricultural fields and urbanized areas. In cities and towns humans provide lots of easy food in the form of garbage. The crows’ intelligence allows them to take advantage of novel food items– like pizza and Cheetos–that don’t really resemble food in the wild.

Finally, listen to the difference in sound: Here are two crows calling—an adult and a juvenile https://xeno-canto.org/72977 . Now listen to the throatier sound of the raven https://xeno-canto.org/12581 [Updated February 11, 2026]
Crows will also scream, rattle, whine and coo, but most of the time they just caw. Ravens have a richer, more complex vocabulary. They’ll scream, trill, knock, croak, cackle, warble, yell, and kaw. Young birds reared in isolation have even been taught to say “Nevermore.”

Thanks to Ryan O’Donnell and Andrew Spencer for their recordings available on the web at www.xeno-canto.org

For Wild About Utah, I’m Holly Strand.

Credits:

Theme: Courtesy & Copyright Don Anderson as performed by Leaping Lulu
Photos: Courtesy US National Park Service &
Courtesy & Copyright © 2011 Wayne Whaley
Text & Voice: Holly Strand

Sources & Additional Reading:

Boarman, William I. and Bernd Heinrich. v1.9 March 4, 2020. Common Raven (Corvus corax), The Birds of the World. Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of the World: https://birdsoftheworld.org/bow/species/comrav/cur/introduction [Updated February 11, 2026]

Kilham, Lawrence. 1989. The American crow and the common raven. W. L. Moody Jr. Natural History Series. College Station: Texas A&M University Press. https://www.amazon.com/American-Common-Raven-Natural-History/dp/0890964661/ [Updated February 11, 2026]

Marzluff, John M. 2005. In the company of crows and ravens. Yale University Press. https://www.amazon.com/Company-Crows-Ravens-John-Marzluff/dp/0300122551/ [Updated February 11, 2026]

Savage, Candace Sherk , 1997. Bird brains: the intelligence of crows, ravens, magpies, and jays. Sierra Club Books. https://www.amazon.com/Bird-Brains-Intelligence-Ravens-Magpies/dp/1771644257/ [Updated February 11, 2026]

Verbeek, N. A. and C. Caffrey. v1.5, December 24, 2025. American Crow (Corvus brachyrhynchos), The Birds of the World Online. Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of the World Online: https://birdsoftheworld.org/bow/species/amecro/cur/introduction [Updated February 11, 2026]

August 18, 2011February 22, 2018

Stromatolites

Hi I’m Holly Strand.

Shark Bay in Northwest Australia is on my “places to see before I die” list. In a section of the bay called Hamelin Pond, colonies of microbes form hard, dome-shaped, deposits. Called stromatolites, these structures embody one of the oldest forms of life on earth. The fossil record of microbes in older stromatolites date back 3.5 billion years. Their antiquity, abundance, and persistence to modern times make stromatolites a fascinating subject for scientific inquiry.

Basically, stromatolites are layered structures formed primarily by cyanobacteria. This photosynthesizing bacteria changes the pH of the water causing calcium carbonate to precipitate over a mat of bacterial filaments. The minerals, along with grains of sediment in the water, are trapped in a layer of goo that surrounds the bacterial colonies. Then the lower layer bacteria grows upward and penetrates the most recent mineral and sediment layer. When this process is repeated over and over, a stromatolite is formed.

For over 2 billion years stromatolites dominated the shallow seas and formed extensive reef tracts rivaling those of modern coral reefs. However, today, stromatolites are relatively rare. You will usually find them growing in extreme environments, such as hypersaline water or thermal springs.

While Shark Bay boasts a stunning example of a modern stromatolite colony, you don’t have to go all the way to Australia. When lake levels are low, you can easily see them in the Great Salt Lake. They span hundreds of square kilometers in shallow shoreline waters. Some say that the Great Salt Lake contains some of the most extensive areal coverage of living stromatolites in the world.

One of the best places to view them is from the shore near Buffalo Point on Antelope Island. When conditions are clear, you can see them underwater at the mouth of the Great Salt Lake Marina.

More than just memorials to ancient life, the stromatolites also play a vital role in Great Salt Lake ecology. They are the principal habitat for the brine fly larvae and pupae. In turn, brine flies are a critical diet for goldeneye ducks, American avocets and many other water birds.

Thanks to Wayne Wurtsbaugh, from Utah State University’s College of Natural Resources for his support in developing this Wild About Utah episode.

For Wild About Utah, I’m Holly Strand.

Credits:

Photos: Courtesy Utah Division of Wildlife Resources, Wayne A. Wurtsbaugh and Linda L’Ai
Text: Holly Strand

Sources & Additional Reading:

National Park Service. Stomatolite Fossils. https://www.nps.gov/care/naturescience/stromatolite.htm [Accessed August 16, 2011]

Schopf, J.William. Anatoliy B Kudryavtsev; Andrew D Czaja; Abhishek B Tripathi. 2007. Evidence of Archean life: Stromatolites and microfossils. Precambian Research, 158. No. 3-4 pp. 141-155.

UNESCO Shark Bay Western Australia https://whc.unesco.org/en/list/578 [Accessed August 16, 2011]

University of California Museum of Paleontology. Cyanobacteria: Fossil Record https://www.ucmp.berkeley.edu/bacteria/cyanofr.html [Accessed August 16, 2011]

Walter, M R. 1983. Archean stromatolites – Evidence of the earth’s earliest benthos
Earth’s earliest biosphere: Its origin and evolution. Princeton, NJ, Princeton University Press.

Wurtsbaugh, W.A. 2009. Biostromes, brine flies, birds and the bioaccumulation of selenium in Great Salt Lake, Utah. Pp. 1-15 In: A. Oren, D. Naftz, P. Palacios & W.A. Wurtsbaugh (eds). Saline Lakes Around the World:Unique Systems with Unique Values. Natural Resources and Environmental Issues, volume XV. S.J. and Jessie Quinney Natural Resources Research Library, Logan , Utah. URL: https://www.cnr.usu.edu/quinney/files/uploads/NREI2009online.pdf