Mexican Free-Tailed Bat – Tadarida brasiliensis

Mexican Free-Tailed BatIn honor of Bat Week beginning on October 24th, this Species of the Week will be Oklahoma’s most abundant bat species – the Mexican Free-tailed Bat (Tadarida brasiliensis).  This bat was named the official “Oklahoma State Flying Mammal” in 2006! 

Mexican Free-tailed Bats are migratory, and by now they have left for their winter location in Mexico.  In the spring they come north to spend the summers across the southwestern U.S.  Several large maternity colonies have been found in western Oklahoma gypsum caves where tens of thousands of bats congregate and raise their pups.  

These bats are important pest control agents across the agricultural lands of western Oklahoma; eating moths, wasps, leaf beetles, and other insect pests.  Each night, these bats can eat up to 2/3 of their body weight in insects – especially when females are feeding their young!

Back in 2012, I helped with a research project that was testing a new method to count bats as they emerged from their cave.  Here is a video I took during that summer of the bats emerging from a cave on private property in southwestern Oklahoma.  This “river of bats” flowed for over 30 minutes!

You can read all about the project, which I wrote about in our Registry News Spring 2013  issue.

You can watch Mexican Free-Tailed Bats emerge from a cave too!  The Oklahoma Department of Wildlife Conservation hosts bat nights in late summer so that visitors can watch the 1000s of bat emerge from Selman Bat Cave at nightfall.