Understanding Central Oregon Bats – Natural History and Coexistence Solutions

Understanding Central Oregon Bats: Bat Natural History and Coexistence Solutions

Little brown myotis bat
Little brown myotis bat (Dr. William J Weber)

October is Bat Appreciation Month, but at Think Wild, we appreciate bats all year! As we celebrate these fascinating creatures, let’s begin by exploring their natural history.

Bats, the only flying mammals in Oregon, are often seen as mysterious, creepy creatures, but are not to be feared! These small nocturnal animals are typically found either solitary or in small colonies throughout Oregon. Contrary to common perception, the largest bat species in Oregon, the Hoary Bat, weighs only 1 ounce!

Physiologically, bats are highly specialized for flight. Their wing structure consists of elongated finger bones covered by a thin membrane of skin, creating the wing’s framework. This adaptation allows for powered flight and exceptional maneuverability. Interestingly, bats have a lower metabolic rate compared to most mammals of their size, which helps conserve energy during extended flights. They also exhibit torpor, a state of reduced metabolic activity, during periods of cold weather or food scarcity to conserve energy.

A little brown bat with white-nose syndrome
A little brown bat with white-nose syndrome (Marvin Moriarty/USFWS)

Beyond their unique physiology, bats play a crucial role in our ecosystem. In North America, bats are primarily insectivores, with a few exceptions that feed on fruit or nectar. They are predominantly nocturnal, with highest activity just after dusk and right before dawn. Using echolocation, bats emit high-frequency sounds that bounce off objects, allowing them to navigate and locate prey. This biological sonar system not only aids in hunting but also helps them avoid obstacles during flight. The foraging behavior of North American bats plays a vital role in controlling insect populations, making them essential allies in pest control for agriculture and forestry. However, bats face a multitude of threats. Pesticide use, habitat loss, domestic cat predation, and the fungal White-nose syndrome have pushed many bat species to the brink of extinction.


Bats and Human Habitats

A Silver-Haired Bat next to nickel for size comparison
A silver-haired bat next to a nickel for size comparison (Andy Bronson / The Herald)

As human development continues to encroach upon natural environments, bats have adapted to our changing world. Human structures, with their nooks and crannies, often serve as convenient bat roosts. In particular, bats use these spaces for nurturing their young, creating maternity colonies in unexpected places. Young bats, unable to fly or fend for themselves during their early weeks of life, rely entirely on their mother’s milk. This reliance can sometimes lead to juveniles ending up in unwelcome locations. 

The relationship between bats and humans goes back thousands of years, possibly to the days when early humans began constructing buildings and shelters. Over the ages, bats have been observed using buildings for various purposes, including roosting, foraging, temporary shelter, reproduction, and hibernation.

This lifestyle offers bats several advantages. They thrive in the warmth of human-made structures, which can lead to quicker gestation and faster development of their young. Additionally, urban environments often provide protection from natural predators, giving bats a safer haven. This adaptability allows bats to utilize buildings as stepping stones, helping them explore habitats that lack natural roosting structures and potentially expanding their geographic ranges.

However, coexisting with humans in buildings also comes with its share of risks for bats. These risks include exposure to chemical pollutants, especially those used in preservation or pest control measures. Bats may also face direct persecution or accidental harm when trapped within buildings. Therefore, it’s crucial to approach the eviction of bats from buildings with a well-considered strategy that takes their natural history into account.


Coexisting with Bats

Think Wild staff perform a bat exclusion on a home
Think Wild staff perform a bat exclusion on a home (Sue Dougherty)

If you’ve found bats taking up residence in your home, it’s essential to address the situation with care and respect for these creatures. The best way to prevent bats from entering your house is to “bat-proof” your home, finding and blocking spaces through which bats are entering. Identifying every potential entry point can be a challenge, as most bats can slip through openings as narrow as a nickel. Timing is also critical: bat eviction and exclusion must occur outside the breeding, birthing and nursing season (Spring-Summer) to avoid trapping juvenile bats inside. Think Wild can perform evictions and exclusions of bats through our Humane Wildlife Services Program.

Another proactive step is to consider installing a bat nest box. These structures offer bats an alternative to roosting in your roof and can be placed in a variety of locations including in a tree or directly on the side of your home. Think Wild sells bat boxes and offers installation services to help situate your bat house in an optimal location.

bat nest box on a tree
Bat nest box on a tree

Bat-proofing your home and providing alternative roosting sites can support Central Oregon’s bat populations, helping decrease conflicts with these insect eaters while still enjoying the benefits of their presence. Bats, with their unique natural history and remarkable adaptations, are integral to our ecosystem. By understanding bats’ needs and challenges, and by adopting coexistence strategies that prioritize their well-being, we can ensure that bats have safe habitats for roosting, hibernating, and reproducing. So, as we appreciate bats during Bat Appreciation Month, let’s also strive for year-round coexistence with these essential members of our ecosystem.