Field Guide/Mammals/Silver-haired Bat

Lasionnycteris Notivagans (Silver-Haired Bat)

Family: bat family Size: • Total length: o 3.6 to 4.5 in (92 to 115mm) • Tail length: o 1.4 to 1.8 in (35 to 45mm) • Weight: o .28 to .39 oz (8.1 to 11g) Description: This particular bat has a distinguishing black coat with silver or white tips. They also have black wings and black ears. Their ears are short, rounded, and have no hair on them. Similar Species: • The most distinguishing feature of these bats is the color of their hair. They are easy to spot because they are the only bats that have that particular silver tipped hair. Range: • This animal can be found throughout North America. • They range from as far north as Alaska and as far south as Mexico. • They range from as far west as California and as far east as Georgia. Habitat: • This species prefers to live in temperate areas in the northern woodlands that has some source of water nearby. • They generally roost in trees such as willows, ash, and maple trees. It is not as common but they have also been known to roost in some buildings. • In the winter they roost inside of trees, buildings, and the cracks of rocks. Diet: • These animals are insectivorous o They eat small, soft bodied insects such as flies, moths, mosquitoes, beetles, and crickets. o They generally look for food in the tree tops but they also search in small clearings and near water. Activity: • These animals are nocturnal. At night they fly generally late compared to other bats starting after other animals have already started eating. • They have 2 periods in the night that they are active. Their first period is typically 2 to 4 hours after sunset and their second occurs 6 to 8 hours after sunset. • They have a generally slow flight speed of 15.7 f/s (4.8 m/s). • Unlike other bats they do not hibernate in the winter they actually migrate south towards Mexico in the autumn and then return north in the spring. Reproduction: • This species in particular species reproduces in a unique way called delayed fertilization. Mating occurs from August to October and then ovulation occurs in April to May when they return north. • The typical female has around 1 to 2 offspring in each attempt. • The gestational period is approximately 50 to 60 days. • Weaning lasts until the offspring is around 3 to 4 weeks old. • Offspring reach sexual maturity typically in the late summer or fall. Lifespan: The life span of this particular bat is generally 12 years of age. Notes: Silver haired bats, along with any other kind of bat should be considered Minnesotan’s best friend as they eat the mosquitoes and other insects that bother us every year. This bat can be distinguished from others because of its black hair with white or silver tips. It is a medium sized bat that has a small wingspan compared to others. It is nocturnal so a night trip will be necessary to see this extraordinary animal. Look for them in the later part of the night as they generally fly much later than other bats. This bat is typically found in woodland areas near water but otherwise all over Minnesota and the rest of the country. They prefer to live in willow, ash, or maple trees. In the winter they do not hibernate as most animals do they migrate south making it impossible to spot them during that time. However, you will not want to get too close to these animals as this particular bat has been known to be common carriers of rabies.

Silver haired bat in captivity