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The world's only flying mammals are right here in Boulder. They appear at dusk over ponds and waterways to drink and forage. Most people are entirely unaware of their presence, much less their benefits to the ecosystem. The rich ecosystems of OSMP are a great place to be a bat! The rock formations of the famous Flatirons create nooks and crannies that provide just the right combination of warmth and air flow into which the bats comfortably wedge themselves. Roughly 40 species of bats inhabit the United States, and 18 of those species live in Colorado.

Boulder County is home to 11 different species of bats, one-quarter of all the bat species present in the U.S. Along the foothills of the Rockies, we find the western edge of the range of eastern U.S. species of bats like the Red Bat. We also find the northern-most record in Colorado of the Brazilian Free-Tailed Bat. Although the Hoary Bat typically breeds farther north than Colorado, pregnant females have been observed. The diversity and richness of species here is magnificent and offers alert visitors a chance to observe bats around dusk as they flutter through the plains and canyons.

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So, why are bats important?

  • They are significant predators of night-flying insects. A single little brown bat can catch 600 mosquitoes in just one hour. A colony of 150 big brown bats can protect local farmers from up to 18 million or more rootworms each summer. The 20 million Mexican free-tails from Bracken Cave, Texas eat 250 tons of insects nightly. A decline in bat populations increases the demand for chemical pesticides.

  • Our desert ecosystems would fail without bats. The bats pollinate the saguaro, organ pipe cactus and the agave. Many other plants and animals rely on these plants for food and shelter. If they were to die out, the entire desert ecosystem as we know it would collapse. Next time you slice a banana for your cereal or enjoy a mango, thank a bat. The wild stocks of these fruits are dependent upon bats for their pollination and seed dispersal. Dates, breadfruits, cashews and figs are also dependent on bats.

  • Bat guano is used as fertilizer and supports a bacteria that is used in detoxifying wastes, improving detergents, and producing gasohol, and antibiotics.

  • The vampire bat produces an anticoagulant that is more effective than any medical research has developed, and for this reason is being studied. Anticoagulants are important during operations and in the treatment of heart patients.

  • Bats' echolocation is a thousand times more sophisticated than any human produced sonar and is studied in the hopes of improving our technology.

Townsend's Big Eared Bat, which occurs in the Boulder area, is a sensitive species in need of immediate protection. Only eleven breeding colonies are known in Colorado; two of them are on OSMP.

Seasonal wildlife closures protect this and other species. 

Much More to Learn

We have been given a small glimpse into the habits and status of the bats that reside here. Much is yet to be accomplished. Little is known about the day and night roosting site usage, patterns of reproduction, location of maternity sites, overall distribution and hibernation. Nearly 40 percent of American bat species are in decline or listed as endangered. Bats are especially vulnerable to extinction, in part due to their low reproductive rate — the slowest reproducing mammals on earth for their size.