Unexpected Threats Endanger Bats

Mysterious fungus affecting east coast bats while disturbance from southwest border wall construction and surveillance affect major colonies. Pesticides harm food sources

Bats in the US are being hit from all directions yet, since very few people really comprehend their importance, efforts to protect them are limited. Probably the single biggest danger to bats is the excessive use of pesticides. Most US bats are insectivores which eat many pest species. Food sources for bats are destroyed when insects are killed with pesticides. And bats may be directly harmed by pesticide spraying schedules.

In the northeast white-nose syndrome has had a significant effect on bat colonies, and the problem is spreading. There is some speculation that, with less food available, the bats are more susceptible to opportunistic infections such as the fungus which is behind white-nose syndrome.

And few people would have predicted that the US Mexico border wall would affect bats. After all, bats can fly, can’t they? But bat colonies are easily disturbed by activity and noise. Startled young bats may lose their grip, fall to the cave floor and be unable to return to their mothers. Some new sections of the wall are being constructed near key bat caves. In addition, border surveillance equipment emits sounds that may interfere with the echolocation that bats depend on for finding their way around and locating food.

The situation bats face is not uncommon. Humans rarely think about the impact their activities may have on other species. We often realize after the fact that we could have done things differently and saved some animals, like bats, in the process. We will need to start doing more proactive assessment of our impacts on other species if we are ever going to slow the extinction landslide we have started.