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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[/caption]

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/

 

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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

 

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Blue Orchard Bee

Blue Orchard Bee
Copyright Jim Cane

It’s early spring, the time of fruit tree bloom. Apricots, apples, plums, cherries, and pears will all need bees to pollinate their flowers. Traditionally, we’ve used the European honey bee, but now we know how to pollinate our fruit trees using one of our native bees, the blue orchard bee (Osmia lignaria). These bees fly nationwide.

In Utah they occupy many foothill and lower montane habitats. They aren’t social; every female is fertile and tends to her own tiny nest. Adults are active and nesting for only 3-4 weeks in the spring. These bees naturally nest in the tunnels chewed by large wood-boring beetles in tree trunks. Each female partitions the tunnel into a series of little bee-sized rooms. Each room is stocked with a bee-sized provision of pollen moistened with nectar, followed by a single egg. Nest cells are partitioned, and ultimately capped, with mud, a trait shared with other so-called “mason bees”.

Drill Log with 5/16 holes
5 to 6 inches deep
Copyright Jim Cane

You can have your own backyard population of blue orchard bees. One easy way to start is with a short fat log that is seasoned and dry. Take a 5/16 bit and drill 20 or more holes 5 to 6 inches deep. Stand the log on end, facing the holes towards the southeast.

On cold mornings, females bask in the sun before taking flight. If your log is colonized, then you’ll see steely blue bees busily coming and going all day long during fruit tree bloom. They tote their loads of dry yellow pollen in a brush of hair beneath the abdomen. Unloading that pollen at the nest necessitates some charming acrobatics, part of their undeniable entertainment value. Successive generations will nest for you every spring, but you’ll want to switch to better nesting materials to practice good bee hygiene.

A Colonized log
Copyright Jim Cane

Details and links can be found at our Wild About Utah website.

This is Linda Kervin for Bridgerland Audubon Society.

Credits:
Pictures: Courtesy and Copyright Jim Cane
Text: Jim Cane, Bridgerland Audubon Society

Additional Reading:

https://www.sare.org/publications/bob.htm

https://www.ars.usda.gov/Research/docs.htm?docid=18333

https://www.pollinatorparadise.com/Binderboards
/Hornfaced_Bees.htm

Blue Orchard Bee eggs
on pollen provision mass
in nest
Copyright Jim Cane
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Spring’s Earliest Butterflies

Mourning cloak butterfly courtesy and copyright 2010 Don Rolfs
Mourning cloak butterfly (pinned)
Photo by Don Rolfs 2010

Utah’s earliest solar collectors are smaller than a credit card; their carbon footprints are likewise tiny. They convert the sun’s energy to heat, not electricity, and they self multiply. I am referring to butterflies, particularly those that can be found flying on sunny days of late winter while our snow still lingers.

Our earliest butterflies transformed to adults last fall and have spent the winter wedged in nooks and crannies, such as cracks in deadwood or under flaps of bark. The butterflies’ names are generally more colorful than their appearance: red admirals, painted ladies, mourning cloaks, tortoise shells, commas and question marks. Their wing edges are scalloped and irregular, the topsides patterned or banded in tawny browns and muted oranges sometimes edged with yellow or red. Beneath, they tend to be camouflaged with patterns in shades of brown like a moldering leaf.

Satyr Anglewing butterfly
Photo © Jim Cane 2010

Being insects, butterflies generate little metabolic heat, so for warmth they quite literally turn to the sun on chilly spring days. Watch where they land and you will see them with their wings folded over their backs, their stance and tilt perfectly aligning their wings perpendicular to the sun’s rays. The sunshine that they intercept warms their bodies and enables them to fly even when the air is cold. Butterflies of early spring often fuel their flights with the sugars of tree sap where it leaks from a bark injury.

The mourning cloak butterfly is particularly recognizable, it’s rich brown wings edged with gold like gilt paint.

Red Admiral Butterfly
Thomas G. Barnes
US FWS Digital Library

If you see a mourning cloak flying among willows, watch carefully, for the females will be laying their tiny eggs singly on the tips of young emerging willow leaves. Like our migratory birds, the appearance of these early butterflies are living harbingers of the spring to come, a welcome sight indeed.

This is Linda Kervin for Bridgerland Audubon Society.

Credits:

Pictures: Don Rolfs
Jim Cane, Bridgerland Audubon Society

Painted Lady Butterfly
Thomas G. Barnes
US FWS Digital Library

Thomas G. Barnes, US FWS
Text: Jim Cane, Bridgerland Audubon Society

Additional Reading:

The National Audubon Society Field Guide to North American Butterflies, Robert Michael Pyle, National Audubon Society, https://www.amazon.com/National-Audubon-Society-American-Butterflies/dp/0394519140

Peterson First Guide to Butterflies and Moths, Paul A. Opler, Roger Tory Peterson, and Amy Bartlett Wright, Houghton Mifflin Harcourt, https://www.amazon.com/Peterson-First-Guide-Butterflies-Moths/dp/0395906652

Butterflies on Utah Bug Club web site, Utah Lepidopterists’ Society, https://www.utahbugclub.org/finding-utah-butterflies.php

Butterflies of Utah, Butterflies and Moths of North America, https://www.butterfliesandmoths.org/map?ds=45&_dcs=1

Question Mark Butterfly
Thomas G. Barnes
US FWS Digital Library

Painted Lady

Red Admiral

Mourning Cloak

Grey Comma

Milbert’s Tortoiseshell