Episode Archive - Page 181 of 220

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

August 11, 2011January 24, 2021

Fitting the bill

Few among us would choose to eat a steak with a spoon or soup with a fork. And in the world of birds, it’s the same story – you need the right tool for the right job – and you can tell a lot about a bird by paying attention to its beak.Fitting the bill

Physiologically, beaks are a specialized extension of the skull and are coated in keratin – the same material that makes up our fingernails. And like our fingernails, the cutting edges of the beak can be re-grown as they are worn down by use.

Birds use beaks for a multitude of tasks including preening, weaving nests, and defending territories. However it is the task of eating that seems to dictate beak shape and size. Envision the hummingbird, for instance. Its long, thin beak – and corresponding tongue – is designed to reach deep into flowers to collect the nectar within. A hummingbird beak would not work for a woodpecker or a great horned owl. Likewise an eagle’s beak needs to be sharp and strong for tearing flesh, and wouldn’t suit the lifestyle of an ibis or a sparrow.

One Utah native, the aptly-named red crossbill, has one of the most unique beaks around. When closed, its curved top and bottom bills overlap crossways in what looks like an awkward and uncomfortable pose.

French naturalist Count Buffon, first laid eyes on a crossbill in the mid-1700’s. The bird was collected in the Americas, then shipped abroad for examination. Without observing the crossbill in its natural habitat, Buffon labeled its beak “an error and defect of nature, and a useless deformity.” More than 50 years later, Scottish-American naturalist Alexander Wilson observed a crossbill in the wild and determined that its beak ‘deformity’ was in reality a magnificently adapted tool. The crossbill’s diet consists mainly of the seeds of conifer trees, and it turns out that the bird’s curiously crossed beak is perfectly adapted to prying apart the scales of pinecones to get at the seeds within.

Members of the finch family, these birds are often seen in flocks and occasionally visit backyard feeders. They are easily identified by their unique beaks, which serve as a reminder that the right tool for the right job can sometimes seem a bit unconventional.

For more information and photographs of crossbills, visit our website at www.wildaboututah.org. 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.
Fitting the Bill-Credits:
Fitting the Bill
Photos: Courtesy & Copyright Paul Higgins(phiggins)www.pbase.com/phiggins
Text: Andrea Liberatore, Stokes Nature Center, logannature.org

Fitting the Bill-Additional Reading:

Benkman, Craig W. 1987. Crossbill Foraging Behavior, Bill Structure, and Patterns of Food Profitability. The Wilson Bulletin 99(3) p. 351-368 https://www.uwyo.edu/benkman/pdfs%20of%20papers/benkman_1987_wilsonbull.pdf

Conniff, Richard. 2011. The Species Seekers: Heroes, Fools and the Mad Pursuit of Life on Earth. W.W. Norton & Company: NY https://www.amazon.com/Species-Seekers-Heroes-Fools-Pursuit/dp/0393341321

Pearson, T. Gilbert (ed.). 1936. Birds of America. Garden City Publishing Company, Inc. Garden City, NY https://www.amazon.com/T-Gilbert-Pearson/dp/1331531268/ref=pd_lpo_14_t_0/144-1525643-4789824

Fitting the bill
Fitting the bill
Fitting the bill

August 4, 2011January 31, 2026

Medusahead Rye

Weedy plants of old world origin threaten natural areas throughout the United States. An invading plant colonizing a completely new area often lacks the insects, diseases and herbivores that kept it in check back in its native homeland. If the introduced plant grows and spreads vigorously, it can spell disaster for the native inhabitants of its new home. With no natural controls in place, it may outcompete native plants and greatly diminish biodiversity. Disturbed or degraded habitats are most susceptible to invasion by Eurasian weeds.

Utah hosts many invasive weeds causing problems throughout the state. One Eurasian grass threatening sagebrush habitat and rangeland is medusahead rye. Medusahead rye probably came to the United States as a seed contaminant in the 1880’s. The seed head is heavy, so on its own, cannot spread far. But the seeds do have a ticket for dispersal: tufted hairs which cling and readily attach to livestock and vehicles. Once on site, medusahead grows vigorously, crowding out other plants.

Medusahead tissue contains abundant silica which slows its decomposition. The accumulation of dead material forms a dense thatch that smothers other plants. This dry thatch layer can also fuel wildfires. In addition, the gritty silica makes medusahead unpalatable, so both domestic and wild grazing animals avoid eating it. Infested ranches can lose 3/4 of their grazing capacity.

Sage grouse are already in trouble due to habitat loss, and medusahead has invaded more than 10 million acres of the sage brush that sage grouse call home. Once invaded by medusahead, sagebrush habitat is very difficult to restore. The best hope is to prevent or at least hinder its spread through management using controlled burns, herbicides and careful grazing. Non-native, invasive plants are among the most serious threats to our natural world and the habitats and species we know and love.

This is Linda Kervin for Bridgerland Audubon Society.

Credits:

Images: Courtesy Steve Dewey & www.invasive.org
Center for Invasive Species and Ecosystem Health, University of Georgia
Text: Linda Kervin, Bridgerland Audubon Society

Additional Reading:

The United States National Arboretum. https://www.usna.usda.gov/ [Formerly ~~https://www.usna.usda.gov/Gardens/invasives.html~~]

Species Profile: Medusahead, National Invasive Species Information Center. https://www.invasivespeciesinfo.gov/terrestrial/plants/medusahead [Updated January 31, 2026]

Forest Service Employees for Environmental Ethics. [Formerly found at ~~https://www.fseee.org/component/content/article/1002329~~

Utah State University Cooperative Extension. https://extension.usu.edu/rangeplants/grasses-and-grasslikes/medusahead [Updated January 31, 2026]

July 28, 2011March 1, 2018

Utah’s Glacial History

Click to view larger image of Moraine with erratics, Photo Courtesy and Copyright Mark Larese-Casanova, Photographer — Moraine with erratics
Photo Courtesy & Copyright
Mark Larese-Casanova, Photographer

Little Cottonwood Canyon
Photo Courtesy & Copyright
Mark Larese-Casanova, Photographer

Click to view larger image of Little Cottonwood Canyon, Photo Courtesy and Copyright Mark Larese-Casanova, Photographer — Moraine with erratics
Photo Courtesy & Copyright
Mark Larese-Casanova, Photographer

Little Cottonwood Canyon
Photo Courtesy & Copyright
Mark Larese-Casanova, Photographer

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

It is amazing to see just how much of an impact the large amount of snowfall from last winter still has on the annual cycle of nature. Of recent note, wildflower blooms in the mountains seem to be at least 2-3 weeks behind normal schedule. Hiking through snow in late July had me thinking about colder times when Utah’s mountains were covered with ice that flowed as glaciers.

The most recent period of glaciation in Utah occurred between 30,000 and 15,000 years ago when Utah’s climate was, on average, up to 30?F cooler. At times during this period, much of the western half of Utah was covered by Lake Bonneville, which contributed tremendous amounts of moisture as snow throughout Utah’s mountain ranges. As the snow accumulated at high elevations, its sheer weight caused it to recrystallize into ice. Once the masses of ice became heavy enough, gravity pulled them down slope, carving out characteristic U-shaped valleys.

At the top of the valleys, where the glaciers formed, we can often find large, bowl-shaped cirques. In the Wasatch Range, the Little Cottonwood Canyon glacier formed at the top, creating Albion Basin, and reached the mouth of the canyon where calved icebergs into Lake Bonneville. The Uinta Mountains contained such large glaciers that even many of the mountain peaks are rounded.

As temperatures warmed during the end of the last ice age, glaciers receded and left behind large piles of soil and rocks, known as moraines. Terminal moraines at the end of a glacier’s path, can act as natural dams to create lakes. Enormous boulders, known as glacial erratics, can often be found discarded along canyons.

While glaciers don’t currently exist in Utah, there are several permanent snowfields in shaded high mountain areas. So, if you’re feeling a little nostalgic and missing that extra long winter we had this year, you still a chance to hike up above 9,000 feet and cool your toes in the snow.

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

Credits:

Images: Courtesy & Copyright Mark Larese-Casanova
Text: Mark Larese-Casanova, Utah Master Naturalist Program at Utah State University Extension.

Additional Reading:

Utah Geological Survey https://geology.utah.gov/surveynotes/gladasked/gladglaciers.htm

Parry, William T. 2005. A Hiking Guide to the Geology of the Wasatch and Uinta Mountains. University of Utah Press.

Stokes, William Lee. 1986. Geology of Utah. Utah Museum of Natural History.