ast bats: an introduction

An Introduction to Bats

What do YOU know about bats????

•Creepy, blind, blood-sucking RODENTS of the night…

• Bats are flying rats• Bats will attack you for no

reason• Bats will fly into your hair• Bats are blind

Actually…..•Those are all just BAT MYTHS•Bats won’t fly into your hair or attack you•They aren’t blind at all•And they aren’t even rodents……

Nobody likes me….

What are Bats?

Kingdom: AnimaliaPhylum: ChordataClass: MammaliaOrder: Chiroptera (hand-wing)Family: Flying Foxes Micro-batsSpecies: 166 759

Of 4200 mammal species, ~1000 are bats!

Bats are the only mammals capable of TRUE powered flight.Bats actually fly with their hands, not their arms!

Illustration from BCI Educator’s Activity Book

Where are the bats?•

Big Brown BatEptesicus fuscus

• One of the most common bats in urban areas and bat houses

• Often roost in buildings- prefers snags in natural habitat

• Often return to maternity roost where they were born

• Forage in a variety of habitats

Photo From BCI: www.batcon.org

Eastern Red BatLasiurus borealis

• Solitary, tree-roosting bat

• Hangs by one foot• Will also hibernate in

leaf litter on forest floor• About 3 young

Photo From BCI: www.batcon.org

Hoary BatLasiurus cinereus

• Solitary, roost among foliage on forest edges

• Can fly 35 km in one night while foraging

• Territorial over foraging sites

• Often migrate with bird flocks

• One of the most widespread bats in North America

Photo From BCI: www.batcon.org

Eastern PipistrellePipistrellus subflavus

• Common in forest edges and near agricultural areas

• One of first bats to emerge in evening

• Forage high in canopy

• Will hibernate in caves and in culverts

Photo From BCI: www.batcon.org

Northen Yellow BatLasiurus intermedius

• Roosts year-round in Spanish moss and palm fronds

• Abundant on the coast

• Will forage over sand dunes and beaches

• Typically have 3 pups

Photo From BCI: www.batcon.org

Bat Facts• Long lived (some up to 30 years)

• Possibly due to reduced metabolic activity during torpor.

• Low birthrate• Temperate zone bats usually have

~1 young/year.• Long period of infant dependency

• 2 month gestation and 1 month of infant dependency

• High survivorship• 50-80% chance of surviving each year

once adulthood is reached.• Common predators of bats are owls,

snakes, hawks and feral cats

What do Bats Eat?• Fruit- frugivore• Flower nectar - nectarivore• Reptiles, amphibians –carnivore• Fish- piscivore • Blood- sangrivore• Mosquitoes/Flies – insectivore

Why Are Bats Important?

• Bats pollinate many plant species.• Bats control insect populations.• They eat up from 50%-100% of their mass in insects (mosquitoes, black flies

moths) every night.

Bat Food Web• Plants are producers because they

get their energy from the sun;• A primary consumer eats producers;• Bats could be considered – Primary consumers if they eat plants– Secondary consumers if they eat

insects that eat plants– Tertiary consumers if they eat the bugs

that eat the bugs that eat the plants.

Food Web = inter-related food chains

What is Echo-location?• Bats chirp and then listen to the echoesechoes

that return from various objects.• Only micro-bats emit high frequency

chirps to use echo-location echo-location for navigation and prey capture.

• Most echolocation calls range from 9 to 200+ kHz (We hear up to 20 kHz).

Animation from www.batcon.org.

Bats and Rabies• Bats can be carriers of rabies.• Rabies is caused by a virus that attacks

the central nervous system.• Rabies can be transmitted through

saliva and can be fatal.• If you are exposed, you will need post-

exposure vaccinations ASAP.

Histoplasmosis• It is a respiratory disease that is

most often associated with droppings from birds, bats and rodents;

• Histoplasmosis is caused by a fungus that grows on the droppings.

• It causes serious flu-like symptoms depending on the exposure/number of spores inhaled and can be fatal.

Threats to Bat Populations• Habitat destruction • Loss of historical roost sites• Disturbance of roost sites, esp. caves• White Nose DiseaseWhite Nose Disease• Ignorance:– General public: negative attitudes– Scientific: Little is known about the

distribution, numbers and requirements of most bats

General Practices that Benefit Bats

• Protection of known or potential roosts, including: hollow trees, abandoned buildings, caves, bridges

• Creating artificial roosts• Maintaining water quality • Wise use of insecticides• Keep cats indoors!• Leave known bat populations

undisturbed

Common Methods For Studying Bat Populations

• Population Surveys: Counts– Roost/Nest– Nightly Dispersal– Ultrasonic Bat Detectors

• Population Surveys: Captures– Mist Nets– Harp Traps– Trip Lines (over water sources)

Basic Habitat Requirements for Bats• ROOST SITES:– Including maternity, bachelor and

hibernation roosts– Caves, hollow trees, stumps, live trees,

abandoned buildings, bridges, culverts, etc.

• FORAGING HABITAT:– Waterways, roads, pipelines, forests,

edges, clearings, beaches, etc.• WATER SOURCES:– Lakes, rivers, streams, bays, stock

tanks, swimming pools, etc.

Bat House DesignBat houses should have the following specs:– AT LEAST 2 ft. tall and 14

in. wide- bigger is better!– Have a 3-6 inch landing

strip covered with plastic hardware cloth below entrances

– Inner partitions (1-4+) should be ½ to 1 in. apart and covered with plastic hardware cloth or roughened manually

– Ventilation slot 6 in. from bottom of house

Photo From BCI: www.batcon.org

Bat House Placement• Full all day sun is

best- minimum is 6 hours of sun exposure a day

• Place near water if possible

• Mount house 15-20 ft. high

• Make sure entrance is unobstructed

Photo From BCI: www.batcon.org

Photo From BCI: www.batcon.org

Hot Topics in Bat Research• Phylogeny and evolution• Functional morphology• Echo-location study• Conservation Biology• North American Bat

Conservation Partnership (NABCP) Strategic Plan