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Living with Bats in Colorado

**Wildlife Pests Require a Wildlife Professional & are NOT Considered Pest Control – We are providing this information as a service to our customers and would be happy to refer you to a wildlife control company to further assist you. **

Eighteen known bat species call Colorado home.  A portion of those species remain in the state year-round while other species are migratory and spend only a portion of the year in Colorado raising their young.  Bats are beneficial to the ecosystems in which they live.  Not only do they contribute to the control of insects, they provide pollination for plants and crops.  Bats are found in every habitat in Colorado from the mountains to the plans and rural open spaces to major cities.

For many, the primary concern associated with bats is their ability to transmit diseases.  In Colorado, the 2 main diseases of focus are histoplasmosis and rabies.  Histoplasmosis is caused by fungus that grows in materials contaminated by the bat guano.  Disturbing the infected areas can release spores which are then inhaled causing infection.  Although many humans that are infected with the fungus show little to no signs of their infection, others exhibit pneumonia like symptoms.  Without treatment, the infection is capable of spreading from the lungs to other organs.  Rabies is a virus transmitted by the saliva of an infected animal.  The most common transmission occurs from bite wounds; however, infected saliva that come in contact with mucus membranes (mouth, eyes or nose) and/or open wounds are potential routes of transmission as well.  Bats are one of the primary vectors for rabies in Colorado, even though recent years have shown an increase in non-bat rabies cases.  Rabies is a virus that infects the central nervous system.  As a result of vaccination protocols in pets, rabies cases have significantly decreased to being one of the rarest human diseases in the United   States. Bats suspected or known to have bitten an animal or human, whenever possible should be contained for rabies testing.  Typically, the bats that are seen flying or roosting in a normal manner are not rabid.  Most commonly, people encounter rabid bats in situations that provide a fair amount of warning.  Bats found on the ground or are acting abnormally are likely sick or injured.  In these situations it is often best to contain the bat and contact a professional for assistance.

Excluding bats from roosting inside of the structure of your home is typically best completed in the fall or winter when a majority of bats have migrated as young bats may be unable to fly and exit the home. Wildlife control and conservation agencies frequently provide services and helpful information in excluding bats from your home.  Residents that enjoy the insect control provided by local bat colonies, but do not want the higher risk of diseases due to bat guano may consider building a bat box to mount on the exterior of their home, a pole or nearby tree in order to encourage the bats to nest in a separate location.  When excluding bats from the home, gaps larger than a quarter of an inch should be sealed using caulking or another appropriate material based on the size of the gap.  Chimney caps, attic vent guards and similar products can be installed in order to exclude bats from utilizing those areas for access to potential roosts.  In regards to clean out of a roost, it is highly recommended to leave the work to a professional due to the health risks associated with the removal of guano.