'Batnadoes' Can Protect California’s Crops.

For anyone driving the Yolo Causeway, the sight can come as a shock. As the summer sun sets behind the marshy floodplain of the Yolo Bypass, a swirling stream of bats soars out from beneath the elevated thoroughfare. To the delight of bat-lovers and a local rice farmer, roughly a quarter-million bats have made the underside of the tall, 3.2-mile causeway their summer home.