Bat Buddies

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BAT BUDDIESIBATS, BATS, BATS SLIDES

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1. (wrinkle-faced bats emerging from cave) This is how most of us have seen bats, but not all bats are like these. Today we are going to see some of the many different kinds of bats that live all over the world. Bats eat lots of different kinds of foods, they come in many colors and sizes, and they live in all kinds of homes.

2. (Lyle's Samoanflyingfox inflight) Bats are in a group called Chriopterans, which means "hand wing." You can see that fmgerbones make up most of the bat's wings. 3. (hand & wing slide) Here we see the comparison of different wing to hand structures: the Pteranodon, bird, bat, human. 4. (flyingfoxface) Bats are the only flying mammals. Who lmows what it means to be a mammal? There are almost 1,000 species or kinds of bats in the world. Rodents, like rats and mice and squirrels, are the only mammals with more species than bats. The fruit bats are also lmown as mega bats, generally having large eyes and long snouts. 5. (lesser mouse-tailed bat in flight) Another group of bats is lmown as micro bats. These bats generally have larger ears and small eyes. They use echolocation to find their food.

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6. (echolocatIon slide) Echolocation is a special ability that bats have to locate their prey. Here we see a drawing of how it works. Who can describe how bats echolocate? 7. (Pallid bat with katydid) This is a very small bat, but it is a meat-eater. It uses echolocation to eat small insects. 8. (fisherman bat) This bat has extra long legs and long claws to catch fish. It listens for sounds made as the fish swims in the water, then it follows those sounds to find the fish. 9. (gothic bat hanging) Bats roost or hang upside down. This helps them build up speed to start flying. Their legs are too weak to get a running start. So a bat hangs upside down then lets go when it is ready to fly. It flaps its wings as it it's falling and that's how its flight starts. 10. (flying fox and bald guy) Bats come in lots of sizes from very big (bigger than the one in this picture even) to ...

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11. (Kitty's hognose batlbumblebee bat), to very tiny. This is the world's smallest bat. It is an endangered species that lives in Thailand. 12. (Hammerhead bat grasping rose apple) Most of the big bats, called megabats, use their eyes and noses to find their food.

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13. (Mexican funnel-eared bat) but most of the small bats, called micro-bats, use their sense of hearing to find food. These bats can see and they use their eyes for far away things, like finding .their way home in the dark. But their hearing is best for close-up stuff, like looking for food and looking out for predators.

14. (Yellow-winged bat) Not all bats are plain brown or black. This is a yellow-winged bat. .. 15. (Greater white bat) and this one is all white ...

16. (Spotted bat) and this one is spotted! Sometimes their colors aren't the only thing that is unusuaL .. 17. (Chapin's free-tailed bat) this bat has a punk hair-do ... 18. (Gambia epauletted fruit bat with figs) ... and some look like they make silly faces. This bat has a mouth full of fruit to eat.

19. (False vampire bat) Who lmows what bats like to eat? This is a large bat (wingspan - 3 ft.) that eats meat. It eats rats, mice and other small animals.

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20. (Lesser long-nosed bat, saguaro cactusjZower) This bat drinks nectar and pollinates flowers, just like bees, butterflies and hummingbirds do. 21. (Fruit bat with mango) This is a fruit bat. Who lmows what kind of fruit it is eating? Do you like mangoes? 22. (Common vampire) this bats only eats blood ... what kind of bat is it? There are NO vampire bats in the United States, and vampires usually bite animals - not people. Do you think animals turn into vampires if they get bitten? Vampire bats are special. Vampire bat moms will take care of orphan vampire bat babies. Most mammals won't do that! 23. (caver) Lots of bats live in caves and people have to be extra careful not to disturb them, especially when the bats are hibernating. 24. (hoary bat in pine) but not all bats live in caves. This hoary bat likes to live by itself in pine trees. 25. (evening bats) These bats live in small family groups - 5 to 10 bats live together. They live in attics, bams, and old buildings.

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26. (Gambian epauletted fruit bat- mother and young) Bat moms usually take very good care of their babies, maybe because they only have a few. Sometimes mom and baby hang out together; either the baby holds onto mom's fur or mom wraps her wing around the baby. 27 . (Mexican free-tailed bat pups) Other babies stay in a nursery while their moms go out to look for food. These babies have pink skin and they haven't got any fur yet. Each pup will drink milk from its mother when she returns. These bat pups are Mexican free-tail bats. What can you tell me about these bats?

28. (Bracken Cave) Central Texas is famous for its colonies of Mexican free-tail bats. About 100 million Mexican free-tail bats come to Central Texas in the spring. This is Bracken Cave. 20 million Mexican free-tail moms and their pups live in this cave between March and November. The guano at the bottom of the cave is used for fertilizer. 29. (Portrait ofMexican free-tail) This is a Mexican free-tail bat up close. What do you think they eat? How do you think they find their food? The Mexican freetail bat is different from other Texas free-tail bats because of its wrinkly lips and because its ears are not connected in the middle.

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30. (Mexicanfree-tail bat infiight) Why do you think they call these bats free-tail? We said that Mexican free-tail bats eat insects. How much do you think they eat? 31. (Bats under Congress Ave. Bridge) These are bats under the Congress Ave. Bridge in Austin. Between 1 mill and 1 Y2 mill Mexican free-tail bats live in Austin from March to Nov. This colony, like the colony at Bracken Cave, is a maternity colony. There is a colony at the McNeil Bridge in Round Rock, which is comprised of about 600,000 male Mexican free-tails. 32. (Bats over Statesman) Have you ever seen the Mexican free-tail emergence at the Congress Ave. Bridge? Our colony is the largest urban bat colony in the U.S. That makes Austin the battiest city in the country! Thousands of tourists come every year to Austin and see our bats. Businesses in our city make about 8 million more dollars each year because of people who come to see our bats. 33. Do you think bats are helpful? How? (pollinating, fertilizing, eating harmful insects, tourism)

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Kelly HarperlKatie LiennannlSherry Winnette (updated Fall '00)

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. 'Bat j-(and6ook for 'Educators ~~ r

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6g CflicKJf Smgtlie 5iustin 9{gture and Science Center --

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1998 •

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Bat Handbook for Educators Introduction A decade ago, I worked at a wildlife hospital in the cold north of Massachusetts. That's where I encountered bats for the first time. Poeple brought in bats that had been injured by their cats. Nobody else would deal with them because of the threat of rabies. We were already very familiar with rabies because of an epidemic in the northeast of raccoonborn rabies. So my colleague and I investigated bats ...in depth. We started reading up on them, calling the world's experts and then caring for orphans that folks brought us ~om a.pesticide laden building. We quickly discovered bats to be fascinating creatures. Before long, we became th~ "experts" on ba~ in the state. Not long afterwards, we started doing school prQgrams with some of our non-releasable bats and once the media got wind of that...well bats become the bulk of our business and our lives. In September of 1992, I had the opportunity to work with Dr. Merlin Tuttle, Founder /Director of Bat Conservation International based in Austin. He invited me to help.him photograph bats in the caves of Tennessee and Kentucky. That's the first time I saw bat emergences and the firsttim~J'd been_!!'t~~ c~y_~ (which is ~ whole other story!). This is where I became totally hooked on. ba~s. -IfIl.)Ust have been when we witnessed mal~s courting females by singing to them, something that excited Dr. Tuttle immensely beca1l:se it had never been observed before. In the intense 9 days I spent in the company of Dr. Tuttle and bats, I experienced a new appreciation for the gentleness and intelligence of these miunderstood· mammals. Dr. Tuttle conviced me that Texas was the place to go if you love bats, since Texas has most of the USA's 42 species. So that's how I ended up in Austin and then decided the Austin Nature Center re~y needed to have a bat program! I hope you find this manual helpful, but better yet, take the opportunities Texas has to offer to observe bats up close and first hand. They are woderful and amazing creatures. And maybe someday ...if you work at it...you will have more bat T-shlrts than I do ...my collection now numbers 21 ... good luck!

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WHY STUDY BATS? > Bats are the only true flying mammals > Bats make up one quarter of all mammals species > Bats playa very essential ecological role > Bats have a very important economic role . > Bats are the number one tourist attraction in Austin > Texas may very well be the "bat State" with Austin, TX.being the $elf-

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proclaimed 'Urban Bat ~apital of the world" One good reason to teach people about bats is that people have so many misconceptions about bats. There are many derogatory statements made about bats for example, I'm sure you've hecu;d of the following: ''Like a Bat out of Hell" "That crazy old Bat" "Blind as a bat" "Gone Batty" "Bats in your belfry"

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You may also have heard have the following bat myths: Bats get tangled in your hair. Bats want to suck your blood. By GARY LARSON Bats will give you rabies. rH; FAR SIDE Bats are vicious. ......--------------, Bats are blind. Bats are dirty. Bats are flying mice. . Bats will ~ttack you.

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convergent evolution. Bats are outnumbered only by the rodents (1700 species out of 4,000 different mammal species total). The ¥e.~b4ts are the OLD WORLD fruit bats, that is'in the continents that all start with an"A", Africa, Asia and Australia (not Antarctica). There are about 175 species of them and they all eat frHtt flowers, nectar and pollen.· As a group, they are Jarger than the Microbats, but sho~ considerable variation, with wingspans approaching six feet. With one exception, Megabats do not echolocate, but rely on vision and smell for night orientation. They generally have large eyes, simple ears and simple, long muzzles. Tail and tail membranes are usually small or non-existent. They usually have short heavy jaws and a large braincase. Many species crush fruit to get at the juice and then spit out the pulp. Nectar and pollen feeders have longer, narrower snouts which with the aide of long tongues, help them to probe deep into flowers. MICROBATS

LWonycteris DII,8olen.sis .

Masked fruit bat, Pteropus persontllUS

Tent-making bat. UrvtMmtI1 bllDbamm

Microbats are a large and diverse group (790 species) found on every 'continent except Antarctica and eat all sorts of thlngs from insects and arthropo<;is to fish, small m~als, frogs, other bats and blood. All orient by echolocation. Ears are often large and complex, many species have nose leaves. Among manuri.al.s, only humans are more widely distributed than bats.

BAT BIOLOGY

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WHAT BATS EAT

The feeding habits of bats are as varied as D;lammals as 'a whole and their varied feeding habits ,are responsible for much of their morphological, physiological and ecological diversity. Bats feed on insects and other arthropods such as scorpions, spiders and crustaceans, both fresh water and marine, mammals, birds, reptiles, carrion and blood, fruit, flowers, nectar, pollen and foliage. Around 70% of all bats are insectivorous: all but a few microbats. The diversity of arthropods was the driving force behind the diversity of microbats. There are only 10 species that are confirmed carnivores. Four species are False Vampires. None of these are small bats. Carnivory probably evolved from insectivory. And most carnivorous bats still take a large number of a.rtJ:ropods. '

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There are two confirmed species of piscivores or fish eaters. These too still ~at arthropods. The most specialized dietary habit may be the sanguivores, or vampires. '

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BAT ANATOMY f'.,

The anatomy of bats clearly shows their classification as mammals, as most of them are well furred (there are a few naked bats). Differences in bats and other mammals are most evident in the skeleton and . cardiovascular system. The skeleton of a bat is do~ated by the wings and the work associated with flight means that their hearts are proportionately larger than the hearts of other mammals. Bat skulls show consider~ble variation in size and shape reflecting differences in life-stYle. The skeleton of a bat shows the distinctive extensions of the arms and fingers that support the wing membrane. The posture of the legs differs greatly from other mammals. When bats are flying their thigh bones stick out to the sides and the lower leg points to the rear. When bats are walking (those that can), their posture is reminiscent of lizards walking.

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Vampire Bat walking

BAT FLIGHT

Bat wings are made of tough leathery membrane that stretches betweel1 four fingers and attachs to the back legs. In some bats, the tail is included in the membrane and acts as a type of rudder. Birds are stonger flyers than bats, but bats have more flexibility than birds because of their unique wing structure which allows them to move the in~vidua1 bones in the wing. The:inner fingers of the bats's wing act as an airfoil to counteract gravity, while the outer fingers provide thrust to propel the bat forward. Bats have powerful chest muscles to drive the wings forward and achieve a variety of maneuvers.

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Since bats fly at mght they cannot take advantage of thermals and glide as some birds do.

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Egyptian fruit bat, Rousettus aegypriacus

u Skeleton of a greater horseshoe bat, Rhinoloph~ ferrumequinum. to show wing structure.

BAT BABIES

Most bats have only one young per year, some may have twins and some may even have quadruplets. Most Microbat moms leave their baby at the roost sight, Megabat moms fly with their babies. When a baby bat is born its feet and thumbs are already adult size so that it can cling to its mom and hang upside down right away. Depending on the type of bat, it is fed milk for a few weeks to several months. The wings of a baby bat are not developed right way, but it soon walks and climbs with its thumbs and explores its roost. When a baby first flies it does not find its own food right away but returns to its mother for a drffil< of milk. Young bats.start to clean themselves when they are still very . small. They sp~nd hours grooming and licking themselves.

BAT MYTHS

Red Bat with babies

As creatures of the night, bats are often seen as symbolic of the

darker side of life. In European paintings, angels are often depicted with bird-like fe~thered wings while devils and dragons bore leather bat-like wings. Bats were also used in magic potions to improve. watchfulness, wakefuln~ss, seeing in the d~k, cures for blindness and as a hair remover. Bats have been included in many coats of arms of families, towns and even regjments. The Mayas of Cental America showed a bat-like god on their -sculptures with bat-like wings and a nose leaf. He was believed to rule caverns and the realm of darkness. Navajo Indians in the South west desert of the USA believed bats to be a link between gods and people, offering·humans helpful ~dance. Creatio!1myths abound in Native American ~d African storytelling explaining how the bat got its wings and became nocturnal.

BATS IN DANGER Bats have few natural predators. Hawks, owls, snakes get a few, but these have little impact on bat numbers. Humans are really the biggest threat to bats.

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People have misunderstood and mistreated bats for centuries. They have hunted them for food and for sport, but the worst harm to bats has . been in the last 50 years,. with h'lIffi to their environment... loss of woodland and forest habitat as well as caves. Tourism in caves, mining and vandalism of caves has destryed many millions of bats. Bats have a reduced food supply due to the spraying of pesticides on crops. In some places, bats have become a delicacy for tourists to eat.

Organizations That Help Bats Bat Conservation International P.O.Box 162603 Austin, TX 78716-2603 512-327-9721

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BATS (The Beneficial Animal Teaching Society) c/o Amanda Lollar 217N. Oak, Mineral Wells, TX 76067 American Bat Conservation Society THIS ORGANIZATION NO LONGER EXISTS Wild Again, Inc. (bat rehab and education) 25 Tami Court Bridgewater, MA 02324. 508-279-1444

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ECHOLOCATION To better understand echolocation, it may be helpful to understand some measurable qualities of sound, such as pitch or frequency, which affects wavelength as well as intensity and loudness. . The pitch or frequency is normally measured in kiloHertz, abbreviated as kHz. one kHz is 1,000 cycles per second or 1000 Her~. Sounds above 20 kHz are called "ultrasonic" because they are beyond the range of "normal" human hearing. The echolocation calls of most bats are ultrasonic and not audible to most people. Higher frequency sOlll1ds have shorter wavelengths than lower frequency sounds. This means that to an echolocating bat, higher frequency sounds can provide more detailed information about a target. However, higher frequency sounds are more rapidly absorbed by the atmosphere. The strength of a sound can be expressed as loudness or intensity. Loudness is a perceptual measure reflecting how a signal sounds to a listener. Intensity is a physical measure of the energy or power of a sound. It is usually measured in decibels, abbreviated as dB. An echolocating bat learns to measure the time it takes for the echo to return from the target and thereby can gauge the distance. The returning echo is not as strong as the initial pulse so the bat can differentiate between the two. .

In 1790, an Italian scienatist names Lazarro Spallanzani proposed that bats could see with their ears. He based this on experiments he conducted flying bats mtotally dark rooms. The next major breakthrough was in late 1930;s when Donald Griffith at Harvard University proveq. that bats actually produced high frequency sound and then naVigated by listening to their echos. Fruit bats with the exception of Egytian Fruit bats do not echolocate. The latter uses tongue clicks and echolocate to find their way in cave roosts, not to find. food. Most bats echolocate by vocalizing with the open ·mouth and so fly ·with their mouth open. Some bats however(most of the ones w / ornately decorated noseleafs) emit sounds through their nostrils. These bats fly with their mouths closed. The outgoing echolocation signal is so intense it would be like having someone scream in your ear. Bats avoid being deaf~ed by their own

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sounds by "turning off" the pathway to the brain that processes the sound for the few milliseconds that the signal is sent. The sounds produced by a bat are so intense, that to produce them, their vocal cords are made of bone, not cartilage. As a bat closes in on its prey, it typically increases the rate of echolocation pulses. This is often called a "feeding buzz". There are a few ~advantages to echolocation, that'is anyone with the "right equipment" can listen in. Some moths can do this and can avoid being eaten by bats by droppmg to the ground. Carnivorous bats that eat bats locate bats that are echolocating to dine on.

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. Foraging strategy in relation to echolocation calls and auditory characteristics. Foraging height is plotted against the best frequency of audition. Bats are loosely divided into gleaners (ground and foliage), above canopy hawkers, low level open-air hawkers, and hawkers in cluttered habitats, and the characteristic sonograms of each group shown (adapted from Neuweiler, 1990).

BAT HANGOUTS

Places where bats go to rest or hibernate are called roosts. Where bats choose to roost depends on the species, the sex, the time of day,the season and what part of the world they live in. Nearly all Megabats roost in the open in trees, but most other bats tuck themselves away in nooks and crannies or hang up under cover in the daytime, or at night in between feedings to digest. Bats pick special roosts for hibernation. Differen~ species have different requirements for air temperC).ture and humidity and so will pick certain caves and particular locations in the cave.

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There are special maternity roosts for certain species, such as Bracken Cave in Texas which is a maternity roost for 20 million Mexican free-tailed bats, or Congress Avenue Bridge in Austin which is a maternity roost for about one and a half million Mexican free-tailed bats.

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Game Station: Bats, bats, bats: see hand out Bat Buddies: Bat, Moth, Moth Have everyone gather in a circle and spread out arms length apart. Select one bat, blindfold them. Then select 3-5 moths. The rest are trees. Explain that with echolocation they see with sound. The bat will say "bat bat bat" and the moth will say "moth moth moth". The trees only say ''tree'' when the bat or moth get to close and are about to hit them. The bat tries to catch the moths.

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Bats, Bats, Bats Game station 1. Split the kids into 5 groups. 2. Give each group a picture of an Austin bat and tell them to look on the back for information that will be important in playing the game. 3. Give each group a dry-erase board. Tell them one member from their group will write the answers to questions down on the board. 4. Tell them that there are cards on the other side of the room/sand pit that they will need to pick up. They range from food to water to habitat. S. If they get a question correct, one person from the group has 5· seconds to pick up one of the cards. Remind them.to make sure they pick up the correct habitat, food, and water for their colony to survive. . 6. Ask each group the same question' and tell them to discuss it within their group and write it down on the board. . 7. Go over the answers to see who has it correct. 8. If they are correct they send over a person to pick a "good" card. 9. If they get it wrong, they pick a card from the "Dangers to bats" can. 10. Ask questions (7-10 min). 11. When done, give them sheets that tell them what the pictures mean. 12. Discuss whether or not their bat colony was good, threatened, endangered, or extinct and why. You may have··to help the kids with their pictures. They may need to have status adjusted depending on cards picked. For example: if they have no water picture, they should be lowered to a threatened listing.

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Mother Bat and Pups In this activity, children wil1leam some facts about bat behavior and have some fun imitating bats.

What You Need • A large space for children to move around in • Materials: plastic·spiders in ziplock, plastic flowers in ziplock

What to Do 1. Ask children to di~cuss what they !mow about bats. You might prompt the discussion by asking questions, such as: Where do bats live? (caves, under bridges, trees, in buildings) What are baby bats called? (pups) What do bats like to eat? (mosquitoes, other insects, nectar andfruit) How do bats move? (they fly) List children's responses on wipe board.

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2. Tell children that they are going to pretend to be bats. Then explain that like many animals, bats learn from their mothers. Have the instructor be the "mother bat." The children will be the "pups." As the mother bat, choose a behavior to teach to your pups. Some suggestions are: • • • • • •

catching insects using their feet flying climbing up obj ects using their thumbs sleeping bat drinking nectar grooming with thumbs

3. Explain that the mother bat must not use words to teach her pups. When the pups have demonstrated that they have learned one behavior, choose another behavior to teach the pups.

TEXAS BAT SPECIES

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LOCATION

Leaf-chinned bat

southern Texas

Me.c-ncan 19n9-tongued bat

big Bend

. Little brown bat

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Southeastern bat

northeast Texas

Yuma bat

southwest desert

Cave bat

central and western Texas

Fringed bat

T.rans-Pecos

Long-legged bat

'Irans-Pecos .

California bat

1i"ans-Pecos

Masked bat

T.rans-Pecos

Sliver-haired bat

. rare - Lubbock

Georgia bat

central, south, and east

Western canyon bat

w.est/northwest Texas

Big brown pat Hoazybat

northern east/west Texas (not 'Travis) rare Texas migrant

Red bat

all of Texas

Seminole bat

deep east Texas

Greater yellow bat

rare, southern coastal and southeast central (Travis) southeastern Texas' (Cameron county)

Lesser yellow bat

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rare - one specimen

BATS and RABIES Rabies is a deadly disease. It is a virus carried through the saliva of mammals. contracted, it is 100% fatal.

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The key word is contract it". The virus has to make its way from the bite site to the nervous system. This is a slower process than one might think. Usually a victim has 24-48 hours to get an injectio~ of the anti-rabies serum so as to prevent rabies. II

(Pre-rabies exposure vaccines that are given to those who work with high risk animal populations still require that one get post-exposure shots if they know they were bitten by a rabid animal. The prophylactic shot just buys you more time.) There have only been 10 people in the U.S. and Canada who have died from rabies·in the past 50 years (more people die of bee stings and from unidentified falling objects falling on.their heads). That is because most people get a shot if they suspect the animal had rabies AND ... the animal must have broken the skin.... AND the rabies virus is not always present in the infected animals saliva, and the concentration may vary. (much like the venom of a viper). Data shows that only about 150/0 of people bitten by a rabid animal would develop symptoms if left untreated.

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Most mammals shed the virus days before showing symptom, bats however are known to be carriers" that is they may harbor the virus while showing symptoms, or may not ever show symptoms. Skunks may harbor the virus for 6 months, cats 1-2 months. Foxes rarely sprread the disease as they die very quickly from it. II

The virus only lives 12-16 hours on d~ad animals or outside the body. Bats don't get aggressive when they have rabies. They show what is referred to as "passive" rabies. Not all sick bats have rabies, but why take a chance? The likelihood of a bat on the gro~d haVing rabies is greater than a bat who is just han~g or flying around. Under normal condition, aboue1 % of all wild mammal populations have rabies. Occasionally epidemics occurr in certain populations (such as coyotes and raccoons). Bats DO NOT HAVE these outbreaks. In Mexican free-tailed bats, the rabies frequency is .5% of the population. That means there could be 7500 rabid bats at the Congress Avenue Bridge. That seems like a lot, but that's because bats do hang out in large groups. When was the last time you saw 20 million coyotes or skunks hanging out together?!

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Data on bats tested at Health Cen.ter labs show that a high percentage of them do test poitive for rabies. But remember this is not a rando~ sample of healthy bats. These are bats that people found on the ground and so are more likely to be sick!

Teaching Resources about Bats

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Bat Conservation International P.O.Box 162603 Austin,' TX 78716-2603 512-327-9721 has many educator's activity books, videos, slide sets, posters Speleobooks Schohaire, NY 518-295-7981 call for catalogue has all kinds of bat and cave related stuff Bats Incredible . AIMS Education Foundation Fresno, California activities for grades 2-4

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Project Underground Richmond, Virgina call for info 804-288-4226 has a project book with Project WILD type activities Ke~pers

of the Night by Michael j. Caduto and Joseph Bruchac, Fulcrum PublishIDg, 1994. has Native American stories and nocturnal activities Discover Nature at Sundown by Eliza1:;>eth Lawlor, Stackpole Books, 1995. Facts and activities local places that usually have "bat stuff" Toadhall Childr~'s Book Store, Austin Bookpeople, Austin .

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BAT CLASSIFICATION and Evolution Bats are not well represented in the fossil record. The oldest bat fossil fOW1d is about SO million years old. It looks like a microbat does today. Scientists have not found any transitional forms. The delicate bodies do not preserve well. Palaeochiropteryx tupaiodon, an Eocene fossil found in Germany

At the same time bats were evolving, so were flowers. This means insects were evolving too. Bats had a lot of niches open to them as nectar feeders, fruit and insect eaters. Bats became a very diverse group. Due to competition from other groups, bats became tree-dwelling and nocturnal. . CHIROPTERA Bats are classified :in the ORDER - ........ -" . ... . .. .... - which is Greek for _ _ ,.._... - """_._a "hand-wing" . -'.~..

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There are two sub-orders; the Micrqchiroptera and the Megachiroptera, commonly referred to as Microbats and Megabats. Most bat biologists do not believe that these two groups are even related however, and so the classification of bats is somewhat artificial. The closest . relative to the Megabats may be the Flying Lemurs or Colugos which ar "not really Lemurs bUfanother group called Dermopterans and they do not fly but glide. The Microbats probably evolved from a small shrew-like mammal. There is a lot of evidence that suggests that flight evolvd twice in mammals and Micro and Mega bats represent a good example of

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Bat Conservation International P.o. Box 162603, Austin, TX 78716 (512) 327-9721 www.batcon.org

Fly!

FREQUENTLY ASKED QUESTIONS ABOUT BATS ARE BATS RELATED TO BIRDS?

Bats and birds both can fly, yet they developed this ability independendy. They belong to different animal classes; birds are in a class called Aves while bats are in the class Mammalia. Bats are mammals, just like humans, which means that all bats are warm-blooded, have hair, bear live young, and feed their babies milk.

How DO BATS MOVE AROUND IN THE DARK? All bats can see, but some use a special sonar system called echolocation. These bats make high frequency calls either out of their mouths or noses and then listen for echos to bounce from the objects in front of them. They are able to form pictures in their brains by listening to reflected sounds just like we form pictures in our brains by interpreting reflected light with our eyes. In this way, bats are able to comfortably move around at night, avoiding predators, maneuvering around obstacles, locating their food, and capturing insects in total darkness. WHY DO BATS HANG UPSIDE DOWN?

Unlike the bodies of other animals, a bat's body is best adapted for hanging upside down. Its hind limbs have rotated 180 degrees so that its knees face backwards. This rotation aids in the bat's ability to navigate in flight and to hang by its feet. Bats actually have specialized tendons that hold their toes in place so that they are able to cling to their roosts umthout expending any energy. In fact, bats must flex their muscles in order to let go of the roosting surface. These adaptations are quite helpful for a flying mammal since bats only need to let go of the roost in order to drop into flight. Hanging upside down also provides bats with roosting space away from predators in safe places on the ceilings of caves. in trees, and buildings that few other animals can use. because they have not evolved to hang upside down by their feet. WHAT DO BATS EAT? There ate nearly 1,000 different

species of bats in the world, living on every continent except Antarctica. Each one has developed special adaptations for how it lives and what it eats. For example, 700/0 of all the bats in the world eat insects and many of them use echolocation in order to fmd food and move around in the dark. Many small insectivorous bats .can eat up to 2,000 mosquito-sized insect in one night. These bats are able to eat so much because they have high metabolisms and expend lots of energy in flight. Frugivorous bats living in tropical climates have very good eyesight and sense of smell for finding ripe fruit to eat. In the desert, there are nectar-feeding bats which have long noses and tongues for harvesting nectar from flowers, as well as special enzymes for digesting the high-protein pollen that accumulates on their faces. Carnivorous bats have sharp claws and teeth for catching small vertebrates such as fish, frogs, birds, or rodents. A few Latin American bats, the vampires, eat only blood.

How DO VAMPIRE BATS SUCK BLOOD? Vampite bats do not actually suck blood. They lap it up like a dog drinking water from a bowl. To begin feeding, the bat first must prick the animal with its two large front teeth, often in the foot or leg of a sleeping mammal or bird. An anticoagulant in the vampire's saliva cause~ the blood to flow without clotting, allowing the bat to lick up its nutritious, protein-fil1ed diet. Vampires take only 2 tablespoons of blood while the host animal continues to sleep. There are just three species of vampire bats in the world and they all live in Latin America. They are very gende ,- ...,features and will adopt orphans and regurgitate and share food for a member of the colony who could not find a meal Vthe night before. The anticoagulant from these bats' saliva has been synthesized and is now used in medication for human heart patients, showing that even vampire bats can be helpful to humans. However, when these bats feed on livestock, they can spread diseases and must be controlled.

How DO SCIENTISTS STUDY BATS? Just like scientists who put radio collars on wolves and dolphins, bat biologists also radio-tag bats using exceptionally small transmitters specially designed to be carried by bats. Once the bat has been tagged, researchers are able to follow it while it forages and returns to its roost. Scientists also use sophisticated night-vision equipment, similar to that usn, by the military, in order to spy on night-flying bats without disturbing them. Researchers can eavesdrop on bat . ,echolocation calls by using "bat detectors" which pick-up their high-frequency sounds and let the scientist know if bats are just flying through an area or if they are actually catching insects.

How LONG DO BATS UVE? The oldest bat caught in the wild was a banded little brown bat (Myotis lucifugus) which was 34 years old at the time of recapture. To put this in perspective, a bat living longer than 30 years is equivalent to a human living longer than 100 years. Bats, for their size, are the world's longest-lived mammals. Yet unlike other mammals of their size, bats have very low reproductive rates, females of most species producing just one pup per year. WHERE DO BATS LIVE?

Not all bats spend their days roosting in caves. Some roost in trees, abandoned mines, buildings, bridges....the list goes on and on. Actually, the variety of bat roosts reflects the amazing diversity of bat species. Bats are highly opportunistic and have adapted to their environments in creative ways in order to take advantage of the many shelters available to them. Southern yellow bats (Lasiurus ega) roost in the hanging dead fronds of palm trees. Other bats, ,', such as Honduran white bats (Ectopbylla alba), chew the midribs of heliconia leaves in order to collapse them into waterproof tents far above the grasp of their predators. Evening bats (Nycticeius humeralis) raise their young under the bark of trees. Some bats even take shelter in the abandoned homes of other animals. For example, the big brown bat (Eptesicus fuscus) occasionally lives inside woodpecker holes in giant cacti. In southeast Asia, tiny club-footed bats (Tylonycteris sp.) roost inside the hollow joints of bamboo stems once occupied by beetles. In Africa, small wooly bats (Kerivoula sp.) use spider webs as roosts. Each species has its own special requirements. Many bat populations are threatened due to loss of their specific roosting habitats. Scientists have studied the roosting requirements of a number of bat species in order to provide appropriate artificial homes for bats. These homes are called bat houses and have 0.. proven to be very successful for some species, if placed in appropriate locations.

How LARGE ARE BATS? The largest bat living in the United States is the western mastiff bat (Eumops perotis), weighing approximately 2 ounces. It has a wing span of nearly 2 feet. However, other bats in the world can be much larger; one fruit-eating flying fox (Pteropus vampyrus) has a wingspan of six feed The smallest bat lives in Thailand and is called the . bumblebee bat (Craseonycteris thonglongyaz). This insectivorous bat has a wingspan of only 6 inches and weighs less than a penny. WHAT ARE FLYING FOXES?

The common name IIflying fox" refers to a group of bats living in the Old World tropics of Australia, Africa, Asia, and the South Pacific Islands. These bats received their common name because their faces resemble those of little foxes. They have large eyes because they do not use echolocation. Instead, they depend on vision and their keen sense of smell to find ripe fruit. Flying foxes help the ecosystems in which they live by pollinating many flowers and spreading see~ to new locations, especially aiding in rain forest regeneration. Do BATS MAKE GOOD PETS?

It is important for people to remember that bats are wild animals and should be allowed to live in th~ natural environments. In fact, it is illegal in many countries to have a bat as a pet. Bats that can be caught are most likely sick and they should not be handled. WHAT IS GUANO?

Guano is the collective term used for bat or bird droppings or feces. For many years, people all over the world have been using guano to fertilize their crops. Today, scientists also are able to extract enzymes from bacteria which live only in guano in order to make laundry detergents and other valuable products. ,-i;"

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The Bats of Texas

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Family Molossidae Eumops perotis - western mastiff bat Nyctinomops [emorasaccus - pocketed free-tailed bat Nyctinomops macrotis - big free-tailed bat V:: Tadarida brasiliensis - Mexican free-tailed bat

Family Mormoopidae Mormoops megalophylla - Peter's ghost-faced bat

Family Phyllostomidae Choeronycteris mexicana - Mexican long-tongued bat Leptonycteris nivalis -long-nosed bat

Family Vespertilionidae

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Antrozous pallidus - pallid bat Corynorhinus rafinesquii - Rafinesque's big-eared bat Corynorhinus townsendii - Townsend's big-eared bat Eptesicus fuscus - big brown bat Euderma maculatum - spotted bat ~ Lasionycteris noctivagans - silver-haired bat LasiuTUS blossevillii - desert red bat -ULasiUTUS borealis - red bat *Lasiurus cinereus - hoary bat Lasiurus ega - southern yellow bat LasiuTUS intermedius - nonhern yellow bat LasiUTttS xanthinzts - western yellow bat Lasiurus seminolus - seminole bat Myotis austroriparius - southeastern myotis Myotis cali/omicus - California myotis Myotis ciliolabrum - western small-footed myotis Myotis lucifigus -little brown bat Myotis tbysanodes - fringed myotis Myotis velifer - cave myotis Myotis volans - long-legged myotis Myotis yumanensis - Yuma myotis ¥ Nycticeius humeralis - evening bat Pipistrellus hesperus - western pipistrelle ~ Pipistrellus subflavus - eastern pipistrelle

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For more information on the bats o/Texas, consult these resouTces: Cockrum, E.L. and Y. Petryszyn. 1992. Mammals of the SOllthwestern United States and Northwestern Mexico. Treasure Chest Publications, Tucson, 192 pp. Davis, W.B. and D.J. Schmidly. 1995. The Mammals of Texas. Texas Parks and Wildlife Press, Austin, 338 pp. Schmidly, D.J. 1991. The Bats otTexas. Texas A&M University Press, College Station, 188 pp. Tuttle, MD. 1997. AmericaJs Neighborhood Bats. University of Texas Press, Austin, 98 pp. Whitaker, J.O., Jr. 1996. National Audtlbon Society Field Guide to North American Mammals. (Rev. Ed.) Alfred A. Knopf, Inc., New York, 942 pp.