Distinctly Montana Magazine

w w w. d i s t i n c t ly m o n ta n a . c o m 25 But when the sun finally sets across Big Sky Country, a new cast of characters appears on Montana's backyard stage. e hawks, swallows, and butterflies active during the day are replaced by owls, bats, and moths when night falls. Animals active at night are known as nocturnal and have highly developed senses to help them navigate and find food in the dark. ere are many reasons why some animals prefer going about their business after dark. Amphibians, like the tiger salamander and boreal chorus frog, are most active at night to avoid the drying heat of the sun. Other animals take to the night to avoid compet- ing with each other for food. If swallows specialize on catching flying insects during the day, bats are their nocturnal counterparts. ere are 15 species of bat in Montana including the little brown bat which can consume 1,200 mosquitoes in one hour. By shifting the time of day they are active, bats and swallows can hunt in the same area without interfering with one another. While swallows use their vision for locating and capturing insects during the day, bats use echolocation to find food at night. Echolocation works in a similar way to sonar. Bats emit a stream of high frequency calls as they fly through the air. e calls bounce off nearby objects back to the bat. Bats can tell how far away some- thing is by how long it takes the sounds to return to them. In this way they build up a sonic map of their surroundings. ough bats take to the night sky to avoid competing with swal- lows, other animals, like northern flying squirrels, are nocturnal to avoid predators. Northern flying squirrels are found in coniferous forests throughout western Montana. Flying squirrels don't actu- ally fly. Instead, these arboreal rodents glide from tree to tree using a specialized flap of skin connecting their forelimbs to their hind limbs. is flap of skin, or patagium, forms an air pocket allowing them to glide up to 160 feet. Flying squirrels have large eyes which help them navigate their nocturnal environment. Like all animals, their eyes are lined with cells called rods and cones. Cones are most useful for daytime vision while rods are best for low light conditions. As you might expect, nocturnal animals have many more rods than cones. Cones T he long days of summer have finally arrived and Montanans across the state are exploring the outdoors from the prairies of the northeast to the Absaroka Mountains in the southwest. Like us, many animals take advantage of summer's bounty. Red-tailed hawks hunt for ground squirrels in open fields. Swallows catch insects flying through the air and butterflies visit the numerous flowering plants in search of nectar. Animals active during the day are known as diurnal. by liSa Baril Nightlife NeAL HerBerT/NATiONAL pArk ServiCe

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