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

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/

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

Snipes Yipes!

Snipe, Heber, UT
Courtesy of and
Copyright © 2008 Kent R. Keller
As found on UtahBirds.org

The wild goose chase, the nocturnal tipping of cows and the snipe hunt are all good-natured tricks to play on gullible friends. Geese and cows are real, of course, but so is the snipe, a chunky relative of sandpipers. Its name may be the “common snipe”, but during most of the year, snipe encounters in Utah are anything but common. A few times annually, I flush snipe unexpectedly from the margins of a montane beaver pond, a patch of cattails along a suburban creek, or around valley springs and marshes, any wet place that gives the snipe mud that to probe for invertebrates and vegetative cover for camouflage. But come spring, the hunt for snipe is more hopeful, as I can listen for the male’s aerial courtship displays high above wet meadows and marsh margins. You aren’t likely to see him looping about at first, but when he periodically dives, the wind vibrating his outer tail feathers creates this distinctive winnowing sound:

[Audio: Common Snipe courtesy and copyright 2006 Kevin Colver available from “Songbirds of Yellowstone” https://www.wildsanctuary.com/the_wildstore.html and westernsoundcsape.org]

Common/Wilson’s Snipe
Courtesy of and Copyright
© 2004 Milton G. Moody
As found on UtahBirds.org

If you hear that sound near dusk or dawn, scan the skies, for you have found the elusive snipe. Wait a bit and he or his mate may perch atop a nearby wooden fencepost, a comical looking bird with its short legs and long delicate bill. A century ago, the snipe hunt was also real; market hunters devastated snipe numbers. Since then, snipe persist wherever their marshes, wet meadows and bogs have not been drained or filled. When next you are out someplace soggy to admire the spectacular plumage of spring ducks, remember to listen for the aerial display of the common snipe.

This is Linda Kervin for Bridgerland Audubon Society.
Credits:
Pictures: Courtesy and Copyright © 2004 Milton G. Moody and Copyright © 2008 Kent R. Keller, as found on utahbirds.org
Also Courtesy Digital Library, US FWS, Photographer W.F. Kubichek
Bird Recordings: Kevin Colver
Text: Linda Kervin, Bridgerland Audubon Society

Additional Reading:

Common Snipe
Courtesy US FWS Digital Library
W.F. Kubichek, Photographer

Wilson’s snipe, Gallinago delicata, Utah Conservation Data Center, Utah Division of Wildlife Services, https://dwrcdc.nr.utah.gov/rsgis2/Search/Display.asp?FlNm=gallgall

Diet composition of wintering Wilson’s Snipe.(SHORT COMMUNICATIONS)(Repo… An article from: The Wilson Journal of Ornithology by Jon T. McCloskey, Jonathan E. Thompson, and Bart M. Ballard, Digital 2009, https://www.amazon.com/composition-wintering-Wilsons-Snipe-COMMUNICATIONS/dp/B002HMJOUG

Wilon’s Snipe, Utah Bird Profiles, UtahBirds.org, https://www.utahbirds.org/birdsofutah/Profiles/CommonSnipe.htm