In 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!