Yolo Basin Foundation's bat expert Corky Quirk know a LOT about the "Bats in our Bypass"! And she freely shared her knowledge and fascinating stories about this non-rodent population. Yep. That's right. Bats are NOT rodents! Even though the German word for them (fledermaus) literally means 'flying mouse', they aren't.
Corky says that about half the mammal species in the world are rodent species, and about half of the rest of the mammal are BATS! Lots and lots of species of BATS -- few of which live in or near Davis. Most of the bats living inside the causeway bridge are Mexican Free-tail Bats which are each about the size of my thumb. With their wings folded closely, they roost in the one-inch-wide expansion cracks under the concrete of the road. They cling to the concrete and huddle together like a huge very long puppy-pile. Sleeping in the day, one can see them streaming out just after sunset all along the 3 miles of causeway between Davis and Sacramento as they head out to feed. Lots of bats. Lots and LOTS of bats!! Over 250,000 bats!!!
(Lois' note: I don't think I have enough exclamation points to express my amazement at some of the things I learned today. Instead, I'll just invite you to listen in to this fast-paced fact-filled BATmania episode.)
By the way. Did you know that baby bats are called pups and are left vercroed to the concrete while their mothers go out and eat? Yep. A purely puppy puppy-pile of bat pups.