Utah’s Bats

Townsend's big-eared bat
Courtesy US National Park Service
Townsend’s big-eared bat
Courtesy US National Park Service
The secret service takes to the sky as we paddle our canoe into a full moonlit Bear River. Our magic sonagram device collects hidden sounds of myriad bats, as they devour tens of thousands of insects. We’re floating through Wuda Ogwa, the Bear River Massacre site now owned by the NW band of the Shoshone Nation, the original owners, who lost it to Euromerican western expansion. A grant funded project being conducted by USU faculty and students, we recorded a remarkable number of species, perhaps influenced by the hot springs cave, that served as wintering grounds for the Shoshone people. There were marked differences in bat species associated with types of riverside vegetation, part of which was the invasive Russian olive.

Utah is home to eighteen species of bats found throughout the state which roost in a variety of habitats including caves, mines, hollow trees, leafy plants, rock cliffs, and buildings. The big free-tailed is the largest in Utah with a wingspan of 17 inches weighing less than an oz. The smallest bat, the western pipistrelle, is the size of a hummingbird and weighs 1/10 oz.

Most Utah bat species are year-round residents hibernating during the winter. Some species migrate south and remain active all year while migrating species breed in the spring. Hibernating bats usually breed in the fall. In the late spring, female bats gather in large nursery colonies where their young, called pups, are born in May or June.

Bats have “slow” life history and are constrained by tight energy budgets. Energetics has emerged as a driver of extinction risk among North American bats. Some of the most wide-ranging species are now on an accelerated trajectory toward extinction as a result of disease and wind energy production. Climate change is also likely to impact many bat species with broad ranges. Urbanization and other kinds of habitat-fragmenting land use changes are also thought to be altering species distribution patterns.

Bats offer many ecosystem benefits. Some subtropic species pollinate plants, many serve as prey to other animals, and cave communities benefit from bat guano which provides nutrients.

Bats benefit humans by eating up to 100 percent of their body weight in insects each night (1000 insects/hour), providing over $3.7 billion worth of pest control each year in the U.S. and reducing the need for pesticides. Their membrane wings and echolocation have inspired technological advances in engineering. The wingsuits used by basejumpers take more than a few cues from bats’ aerodynamic bodies. Utah law protects all bat species. Additional federal protection is extended to species on the Endangered Species List.

Given many gifts bats provide for humans numerous ecosystem services, we can reciprocate by reducing outdoor lighting which disrupts their natural behaviors, avoid disturbing them, especially if they are hibernating, building a bat house, and participating in Bat Week which occurs the last week of October. It’s a time to celebrate and learn about our Utah bats!

Jack Greene for Bridgerland Audubon Society and I’m Wild About Utah bats!

Credits:

Images: Courtesy US FWS, USDA Forest Service and US NPS. All photographers acknowledged with images
Featured Audio: Courtesy & © Friend Weller, https://upr.org/
Text:     Jack Greene, Bridgerland Audubon, https://bridgerlandaudubon.org/
Additional Reading Links: Jack Greene & Lyle Bingham, https://bridgerlandaudubon.org/

Additional Reading:

Wild About Utah Pieces by Jack Greene, https://wildaboututah.org/author/jack/

Strand, Holly, Bats and Echolocation, Wild About Utah, May 13, 2010, https://wildaboututah.org/bats-and-echolocation/

Bunkley, Jessie, Bat Netting at Antelope Island State Park, Wild About Utah, July 11, 2016, https://wildaboututah.org/bat-netting-at-antelope-island-state-park/

Bats, Wild Aware Utah, https://www.wildawareutah.org/wildlife/bats/

Thomas J. Rodhouse, Thomas E. Philippi, William B. Monahan, Kevin T. Castle, A macroecological perspective on strategic bat conservation in the U.S. National Park Service, Ecosphere, ESA, https://esajournals.onlinelibrary.wiley.com/doi/full/10.1002/ecs2.1576

Animal Fact Sheet: Western pipistrelle bat, Arizona-Sonora Desert Museum, https://www.desertmuseum.org/kids/bats/western_pipistrelle.php

Discover the Secret Lives of Bats, National Park Service, https://www.nps.gov/subjects/bats/index.htm

Bat Species in Parks, National Park Service, https://www.nps.gov/subjects/bats/bat-species-in-parks.htm

16 Incredible Pictures Show the Beauty of Bats, National Geographic, https://www.nationalgeographic.com/animals/article/incredible-photos-bat-appreciation-day

Utah’s 18 Bats, Utah Species, Fieldguide.Wildlife.Utah.gov, Utah Division of Wildlife Resources, https://fieldguide.wildlife.utah.gov/?order=chiroptera

  1. Big Free-tailed Bat – Nyctinomops macrotis, https://fieldguide.wildlife.utah.gov/?species=nyctinomops%20macrotis
  2. Brazilian Free-tailed Bat – Tadarida brasiliensis, https://fieldguide.wildlife.utah.gov/?species=tadarida%20brasiliensis
  3. Allen’s Big-eared Bat – Idionycteris phyllotis, https://fieldguide.wildlife.utah.gov/?species=idionycteris%20phyllotis
  4. Big Brown Bat – Eptesicus fuscus, https://fieldguide.wildlife.utah.gov/?species=eptesicus%20fuscus
  5. California Myotis – Myotis californicus, https://fieldguide.wildlife.utah.gov/?species=myotis%20californicus
  6. Canyon Bat – Parastrellus hesperus, https://fieldguide.wildlife.utah.gov/?species=parastrellus%20hesperus
  7. Fringed Myotis – Myotis thysanodes, https://fieldguide.wildlife.utah.gov/?species=myotis%20thysanodes
  8. Hoary Bat – Lasiurus cinereus, https://fieldguide.wildlife.utah.gov/?species=lasiurus%20cinereus
  9. Little Brown Myotis a.k.a. Little Brown Bat – Myotis lucifugus, https://fieldguide.wildlife.utah.gov/?species=myotis%20lucifugus
  10. Long-eared Myotis – Myotis evotis, https://fieldguide.wildlife.utah.gov/?species=myotis%20evotis
  11. Long-legged Myotis – Myotis volans, https://fieldguide.wildlife.utah.gov/?species=myotis%20volans
  12. Pallid Bat – Antrozous pallidus, https://fieldguide.wildlife.utah.gov/?species=antrozous%20pallidus
  13. Silver-haired Bat – Lasionycteris noctivagans, https://fieldguide.wildlife.utah.gov/?species=lasionycteris%20noctivagans
  14. Spotted Bat – Euderma maculatum, https://fieldguide.wildlife.utah.gov/?species=euderma%20maculatum
  15. Townsend’s Big-eared Bat – Corynorhinus townsendii, https://fieldguide.wildlife.utah.gov/?species=corynorhinus%20townsendii
  16. Western Red Bat – Lasiurus blossevillii, https://fieldguide.wildlife.utah.gov/?species=lasiurus%20blossevillii
  17. Western Small-footed Myotis – Myotis ciliolabrum, https://fieldguide.wildlife.utah.gov/?species=myotis%20ciliolabrum
  18. Yuma Myotis – Myotis yumanensis, https://fieldguide.wildlife.utah.gov/?species=myotis%20yumanensis

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