Bats In Los Angeles

Bats



Dance of a butterfly.

Bite of a fox.

Flutter of leathery wings.



Airborne wolves,

Stalking moth and mosquito,

Skimming through marmalade skies.

Mysterious, malicious, misunderstood. Why is it that Western culture thinks so poorly of bats? These hunters and pollinators of the night are vital for controlling populations of insects, especially mosquitos, and instrumental in pollenating fruit crops like banana, mango and avocado. Mother bats are devoted to their offspring and some species will provide food to injured individuals even if they are unrelated, a trait all too infrequent among humans.

Two out of every 10 species of mammals are bats–only rodents are represented by more species. I’ve seen bats at twilight in Istanbul, skimming over a lake in northern Canada, and a friend saw one from the top of the Eiffel Tower in Paris. Bats are found globally except at the poles.

As a child in Los Angeles, I watched them slip in and out of pools of lamplight in the park snatching insects on the fly. Now when I walk at dusk, I see only one or two bats patrolling our neighborhood streets. As mosquito-born diseases, like West Nile virus and malaria, become growing threats you would think people would embrace mosquito predators like bats. Instead, the shortsighted solution is to spray toxins that effect the food web and have short-term effects on the mosquitos.

Bats can live ten to twenty years, with a documented longevity of thirty-two years for a wild little brown bat, while mosquitos typically live 10-100 days. Kill off a generation of bats and mosquitos at the same time and the mosquitos will be back in swarms before the bats can attempt to recover. The resilience of insects to toxins makes this situation even worse. Even the U.S. Center for Disease Control states “There are over 125 mosquito species with documented resistance to one or more insecticides.”

Are there any mosquitos with resistance to bats? No.

A few years ago a mixed colony of big brown bats, little brown bats and Brazilian free-tailed bats were discovered at the Los Angeles Zoo and Botanical Gardens. Here, in the heart of Los Angeles, 100 - 150 bats set out on their summer-evening foray into Griffith Park and along the Los Angeles River to hunt insects.


It isn’t the spectacle of Carlsbad Caverns or Congress Avenue Bridge in Austin, Texas, but watching the small colony emerge in the twilight is exciting. This was the second year Zoo Docents have hosted a Bird & Bat Walk for Zoo members.

Each of the three nights unfolded with similar magic:

As twilight approaches a few bats drop from their daytime roost. An electronic “bat detector” lowers the frequency of the bats' ultrasonic vocalizations to clicks so we can hear them. A few scattered clicks alert us to the emerging “scouts.” They take a look around and then signal to the colony. If the air space is safe, if the barn owl or great horned owl isn’t perched nearby waiting, the clicks will become constant and over the next 10 minutes the majority of the bats will embark on their night of hunting.

Bat Walk slide show - see and hear the bats.

Watching bats is something I could do every night. So we have put up a bat box in hopes of attracting our mosquito-eating neighbors. We’ll keep you posted.