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Bats and Echolocation

Bats and Echolocation: Little Brown Bats, Courtesy U.S. Fish and Wildlife Service, Photographer: W.D. Fritzwater
Little Brown Bats
Photographer: W.D. Fritzwater
Courtesy US FWS

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

There are approximately 4600 mammal species in the world. A fifth—yes, 20%– of these species are bats. They are found everywhere except Antarctica. In Utah they are found at every elevation and in every ecosystem.

Bats are the only mammal that flies. “You forgot about humans,” my very precise husband points out. Well, OK bats are the only mammal that flies without a license and an airplane.

The majority of bats have smallish eyes perhaps leading to the expression “blind as a bat.” But bats are not at all blind. All of them can see and some rely solely on vision for both navigation and foraging. But most bats also have a sixth sense—called echolocation–to navigate and detect prey.

Mariana Fruit Bat
From the
Northern Mariana Islands
Photographer: Ann Hudgins
Courtesy US FWS

Echolocation refers to the process of sending out pulses of sound and listening to
the echoes to locate or avoid objects. Bats emit pulses of high frequency sound from their larynx or voicebox. These sounds are ultrasonic which means that they occur at frequencies beyond the range that humans can hear. The sounds are emitted through the mouth in some bats and through the nose in others.

The sounds bounce off external objects and echoes are returned to the bat’s ear. The size and shape of the bat’s ears help amplify the returning sound. The sound travels through the ear and is converted to vibrations in the inner ear fluid and then on to the brain via the auditory nerve.

Bat brains have unique structures that compare the features of the original sound pulse against the characteristics of the returning echoes. By assembling and assessing the return data, bats can know the direction of and distance of an object. Some bat species have evolved echolocation to such a degree that they can even distinguish shape among individual species of insects.

Townsend’s Big-eared Bat
Courtesy National Park Service

Because of echolocation bats are phenomenal hunters in low light conditions. A single little brown bat can catch 300 to 3,000 insects per night, and a nursing mother little brown bat eats more than her body weight each night — up to 4,500 insects. Hmm. That’s a lot of mosquitoes. I think I’ll invite some bats to my backyard this summer.

Thanks to the Marie Eccles Foundation –the Russell Family for supporting Stokes Nature Center programs.

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

Credits:
Images: Courtesy US FWS and USDA Forest Service
Text: Stokes Nature Center: Holly Strand

Sources & Additional Reading

Bat Conservation International. 1997. Bat Chat: An Introduction to Echolocation
https://www.batcon.org/, https://www.batcon.org/resources/media-education/learning/bat-squad/bat-squad-ep-4-bat-chat-join-the-bat-squad

Wilson, Don E. 1997 Bats in Question: The Smithsonian Answer Book. Smithsonian Institution Press, Washington, DC https://www.amazon.com/Bats-Question-Smithsonian-Answer-Book/dp/1560987391

Bats Live, Prince William County Public Schools, Manassas, VA, https://batslive.pwnet.org/

Bat Week 2015
Sometimes misunderstood, bats are important and fascinating animals. Watch this video to learn some bat facts, find out what challenges are facing bats today and what you can do to help #savethebats.
Bat Week Video

13 Facts About Bats, US Department of the Interior, Blog, 10/24/2016, https://www.doi.gov/blog/13-facts-about-bats

White-nose syndrome: a disease of bats, Wildlife Blog, Utah Division of Wildlife Resources, https://wildlife.utah.gov/news/wildlife-blog/724-white-nose-syndrome-a-disease-of-bats.html

Building nurseries for big-eared bats, Wildlife Blog, Utah Division of Wildlife Resources, https://wildlife.utah.gov/news/wildlife-blog/707-building-nurseries-for-big-eared-bats.html

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Dyer’s Woad

Dyer’s Woad in blossom
Courtesy of and
Copyright © 2009 Brad Kropp
As found on bugwood.org

In early May, pale yellow carpets some hillsides of Northern Utah. The plants are a non-native known as Dyer’s Woad. This Asian member of the cabbage family has been cultivated as a dye and medicinal plant in Europe and Asia for 2000 years. Dyer’s Woad produces a glorious blue dye, but the process is tricky. No synthetic dye equals the color and characteristics of woad dyes.

Woad had arrived in Utah by 1932 as a seed contaminant. Now it is a noxious weed. Woad has a number of unique abilities that contribute to its vigor. Being a biennial plant, it spends the first year of life as a rosette of leaves, building reserves. In its second year, those reserves allow a woad plant to send forth a tall, lanky stem covered with pale yellow flowers that ultimately yield up to 10,000 seeds per plant.

Although Dyer’s Woad is not toxic, few animals relish it either. The seeds have chemicals that inhibit germination and root elongation in other plants, giving woad a competitive edge. Woad causes millions of dollars in losses each year, so control is a major issue. Herbicides and mechanical removal are best used against the rosettes, but nature has provided a native fungus that views woad as dinner. This rust fungus is very effective at eliminating or severely reducing seed production. Plants infected with the rust fungus are misshapen, wrinkly, and covered in dark spots. Those spots brim with rust spores. Therefore, when removing woad, leave the sickly plants to infect yet more woads.

Dyer’s Woad with rust
Courtesy of and
Copyright © 2009 Brad Kropp
As found on bugwood.org

This is Linda Kervin for Bridgerland Audubon Society.
Credits:
Photos: Brad Krupp, Utah State University, Bugwood.org
Text: Michael Piep, Utah Native Plant Society

Additional Reading:

Resources:
Intermountain Herbarium: https://herbarium.usu.edu/

Washington Weed Board: https://www.nwcb.wa.gov/weed_info/Written_findings

/Isatis_tinctoria.html

References:
Edmonds, J. 2006. The History of Woad and the Medieval Woad Vat. https://www.lulu.com/product/paperback/the-history-of-woad-and-the-medieval-woad-vat/4928037

Shaw, R.J. 1989. Vascular Plants of Northern Utah. Utah State University Press, Logan, Utah. https://www.usu.edu/usupress/books/index.cfm?isbn=1417

Welsh, S.L., N D. Atwood, S Goodrich & L.C. Higgins. 2008. A Utah Flora, 4th Ed. Brigham Young University, Provo, Utah. https://www.amazon.com/Utah-Flora-Stanley-L-Welsh/dp/0842525564

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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/

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Pinyon Jays

Click for larger picture, Pinyon Jay courtesy and copyright 2005 Marlene Foard - as found on www.utahbirds.org
Pinyon Jay, Tabiona, Utah
Courtesy and Copyright © 2005 Marlene Foard
As found on UtahBirds.org

Click for larger picture, Pinyon Jay Courtesy US FWS, Dave Menke, Photographer Pinyon Jay
Gymnorhinus cyanocephalus
Courtesy US FWS
Dave Menke, Photographer

Few birds have such a strong association with one plant that the plants name becomes part of the birds name. Sage grouse is one, Acorn Woodpecker another, but the Pinyon Jay is our topic today. Pinyon Jays are usually found in close association with pinyon-juniper forests throughout the Great Basin and the nutritious nuts of the pinyon pine are their preferred food. The blue and grey birds collect and cache pinyon nuts in summer and fall for later consumption. They have an uncanny recovery accuracy and excellent spatial memory, which allows them to rediscover these scattered caches and eat pinyon nuts all year. They do not recover all the stored seeds, however, and therefore aid in the dispersal of pinyon pines.

Pinyon Jays have a complex social organization and are highly gregarious. [https://wildstore.wildsanctuary.com/collections/special-collections]

They spend their lives in large flocks of up to 150 or more individuals. Nesting is communal, although rarely are there more than 2 or 3 nests per tree. Breeding season is in late winter. Many birds spend their entire lives in the flock into which they were born.

Pinyon Jays are not migratory, but they tend to be nomadic; traveling to wherever there is a good crop of pinyon nuts. They will also eat a wide variety of seeds, insects and berries to supplement their diet and can be found in adjoining sagebrush, ponderosa pine forest and riparian habitats. The conservation status of Pinyon Jays is considered vulnerable. Destruction of pinyon-juniper forests for grazing and changes in fire regimes have resulted in loss of habitat. And what is a Pinyon Jay to do without its pinyon nuts?

Thank-you to Kevin Colver for the use of his bird recordings.

This is Linda Kervin for Bridgerland Audubon Society.

Credits:
Pictures: Courtesy and Copyright © 2005 Marlene Foard, as found on utahbirds.org
Also Courtesy US FWS, David Menke, Photographer
Bird Recordings: Kevin Colver https://wildstore.wildsanctuary.com/collections/special-collections
Text: Linda Kervin, Bridgerland Audubon Society

Additional Reading:

Gymnorhinus cyanocephalus (Pinyon Jay), Fire Effects Information, USDA Forest Service, https://www.fs.fed.us/database/feis/animals/bird/gycy/all.html

Avian Cognition Laboratory, Northern Arizona University, https://www4.nau.edu/acl/index.htm

Pinyon Jays, Utah Bird Profiles, UtahBirds.org, https://utahbirds.org/birdsofutah/BirdsL-R/PinyonJay.htm