The big free-tailed bat (Nyctinomops macrotis) is a bat species found in South, North and Central America. This species can be found within Iron County near rocky areas or in canyons roosting in caves and crevices. They have a wingspan of 435 mm and an average length of 140 mm. This species migrates southward during winter. Big free-tailed bats have large, forward facing ears with ridges on the inside. Their noses are upturned and they also have tails that extend past their wings.