A deadly fungal disease affecting bat populations has been detected west of the Continental Divide in Colorado for the first time, raising concerns among wildlife officials. The fungus, Pseudogymnoascus destructans (Pd), is responsible for White-Nose Syndrome (WNS), a devastating disease that has led to significant bat population declines across North America.

The fungus was found in bat guano at the Holzwarth Historic Site on the west side of Rocky Mountain National Park, marking its first confirmed presence in Grand County. Wildlife experts warn that this detection indicates the continued spread of the disease throughout Colorado.

White-Nose Syndrome thrives in cold environments, particularly where bats hibernate. The fungus grows on their skin, wings, and face, causing damage that often leads to death before the bats emerge from hibernation in the spring.

Bats play a crucial role in maintaining healthy ecosystems by consuming thousands of insects each night, including mosquitoes, moths, beetles, and crickets, some of which pose significant agricultural threats. Studies estimate that bats provide between $3 billion and $22 billion annually in pest control services to North American farmers.

While WNS has caused massive population collapses on the East Coast—up to 90% in some cases—Colorado has yet to experience such devastation. However, scientists are actively monitoring bat populations to assess the potential impact of the disease.

A small glimmer of hope lies in the hibernation habits of western bat species. Unlike their eastern counterparts, western bats tend to hibernate in dispersed locations, such as rocky outcrops and crevices, rather than in large colonies. This behavior may slow the spread of the fungus, as fewer bats come into direct contact with infected individuals.

Despite this, experts caution that once the fungus arrives, severe disease and population declines often follow within a few years. Researchers are working on potential solutions, including antifungal treatments, environmental sprays, and even vaccines to help bats combat the disease.

Wildlife officials urge the public to avoid handling bats and to report any dead or injured bats to Colorado Parks and Wildlife at 303-291-7771 or via email at Wildlife.Batline@state.co.us.

The Rocky Mountain Dispatch has previously reported on the spread of White-Nose Syndrome in Colorado, noting concerns from conservation groups about its potential impact on bat populations and local ecosystems.

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