Another myth about bats is that all bats carry
rabies.
Bats do carry rabies; it's about 2% of the
bat population, but you can see from these
graphs, that 2% of the bat population is similar
to the occurrence of rabies with skunks, raccoons,
and other kinds of carnivores.
So, there are some bats that carry rabies,
but not all of them.
The important thing to remember with rabies
is that rabies is basically a fatal disease.
There are two people documented in the literature
who have had a rabies infection, they’ve
been put in a coma for several years, and
they've been able to bring them back slowly,
but basically this is a viral infection that
takes a little while to get to your central
nervous system, but once it gets to your central
nervous system, it's probably going to be
fatal.
Bats don't get the crazy “Cujo” kind of
rabies where they chase after you and try
and attack you.
When they are rabid, they get very calm and
sleepy.
And so, if you see a bat sitting on the side
of a house or a wall, it's two or three feet
up, and it just sitting there not moving around,
that's not a healthy bat.
It should be scared, it should be skittish,
it should be flying away.
If it's just sitting there, not doing anything,
that's potentially a rabid bat.
Now, what's scary is that your cat or dog
could get that, a child could pick it up,
because it's just sitting there and then you
could get accidentally get bit.
So the bottom line with rabies is, if you
encounter a bat, especially on the ground
or during the day, assume it's rabid and do
not touch it.
If it’s somewhere where you need to get
it out of a house or a school, make sure you
use a towel, folded over several layers, so
that you will not come in direct contact with
the organism.
Now I handle bats all the time, and I run
this risk, so what I have is my rabies vaccination.
Just like your dog and cat are vaccinated
for rabies, I've been given a dead form of
the rabies [virus] so that my immune system
is ready to handle that.
I still make sure I don't get bit though,
because getting bit is not that fun!
If exposure to saliva is a possibility, a
bite occurred or a bite could've unknowingly
occurred, then you need to capture the bat
for testing (if that's possible) AND presume
that you got exposed and get post-exposure
rabies shots.
So if you get bit by an organism with rabies,
you can go get post-exposure shots, and that
will give you immunity for a couple weeks,
and that absolutely works.
It won't work if you wait three or four weeks,
but if you go and get those shots right away,
you'll be fine.
It's not 22 shots in the stomach.
There's a lot of sort of horrible stories
about rabies shots - it is an immunoglobulin
shot, so it's a big needle, but it's better
than getting a fatal disease.
I do want to note that you can't get rabies
from a bat flying over you.
You can't get rabies from a bat flying through
your house; the only time you can get rabies
is if you get the virus in your bloodstream,
and it has to come from the bat saliva.
So, I just want to show you some pictures
of some of the bats from Northern California.
We have about 17 species, and the most common
are the little brown bats.
We have six different ones; the big brown
bat, the pallid bat, and the Mexican free-tailed
bat.
We also have some cliff roosting bats: the
pipistrelle, spotted bat, and mastiff bat.
We have cave roosting bats - the Townsend's
big eared bat - and then some tree roosting
bats - Western red, hoary, and silver haired.
I should say the Western pipistrelle, the
cliff roosting bat, its name has been updated
to parastrellus.
So here's one of these little bats.
You can see his little whiskers and his thumbs.
Here, we’re taking some measurements, and
if you look at the piece of paper behind,
that's a key.
A key is a series of questions that help you
look at the organism and determine exactly
which species it is.
Here we’re trying to figure out which of
the different six Myotis sp. this particular
one was.
This is a big brown bat looking a little frazzled.
Here's a pallid bat.
This is the bat that I did my work on.
Here's a pallid bat we finished working with,
we’re ready to let her go, and she turned
around and chattered at us for a while, so
she wasn't quite warm enough, ready to take
off for the evening.
Here's one of the little parastrellus; this
the smallest bat we have in our area.
It’s got this cute little black mask.
They often come out well before dusk; so if
you see very, very small bats flitting around
45 minutes, half an hour before sunset, it's
probably the little parastrellus.
Here's another one of the little Myotis bats
in our area.
Here's a larger bat; this is the hoary bat,
and we’re measuring, with calipers, the
forearm length, which will tell us whether
it's an adult or juvenile.
Notice, for this one, the ears don't stick
out nearly as much.
This is a tree roosting bat.
You can lose too much heat if you have your
ears really exposed and you live out in a
tree.
So here you can see the ears and eyes a little
bit up close.
They have this white tipped fur; it turns
out that that blends in with ponderosa pine
trees perfectly.
Here we can see how much bigger this bat looks
when you actually stretch its legs out; he's
not very happy with us here, and you can see
those very sharp carnivore-like teeth.
This is a red bat; this is another tree roosting
bat that you'll find in cottonwoods and willows
along rivers, so this is a bat that you would
find along the Sacramento or American River.
This is me in a cave down in Rocklin.
This is a Townsend's big eared bat.
This was a very exciting day of my career
when we found six Townsend's big ared bats
in a cave.
They hadn't been documented in the Rocklin
area since 1906, so this was a pretty exciting
find.
This was the best sort of ghostly picture
that we could get, but you can see the big
ears sort of sticking out of the top of the
head.
For this particular site, what we ended up
doing is having a bat gate put in.
This is a mine that's fairly dangerous, and
you don't want kids and people get into trouble
inside of it, but we wanted the bats to still
have their habitat.
So you build a series of horizontal metal
slats that are just far apart enough that
a bat could fly out, but too close together
for a kid to get their head through.
And so now the habitat is protected and it's
also safe for people in the area.
So when we’re capturing bats, we use nets
and generally what we do is we put the nets
out over water near where we think the bats
are roosting.
And so it's kind of a guess where that should
be.
When, they wake up at dusk, they're thirsty,
they're going to go get a drink of water,
and they’re going to get a drink of water
close by, and so we’re trying to catch them
at a place that they’re used to going all
the time.
Now bats can echolocate and absolutely tell
that there's a net, and so most of the night
you watch bats fly over the net, under the
net, and around the net, but every once in
awhile, you catch a couple bats.
If I were to set up a net across your driveway,
in the morning when you're leaving for school,
I would probably catch some of you, even though
you should notice that there was a net there
- you're kind of groggy, you pull out every
morning, and so why look for a net?
Same thing with bats - once you catch a bat
in the net, you will probably never catch
it again.
Some ecological sampling methods that require
that you recapture, and they just don't work
with bats because, once they've gone through
the experience, they will never get caught
again.
So here we've got a bat in a net and we’re
sort of carefully pulling them back out, so
that we can take some measurements.
Here I've got a bat in my hand, taking some
measurements for a class at Sac State.
When we have a bat in hand, we’re going
to try and get as much data as we can.
It can be a traumatic experience for the bats,
so we want to get their age, everything we
can about them, reproductive status, so we
can add that to the growing database of what
we know about the local bats.
Several years ago, I got the opportunity to
go to Belize and see some bats there.
So here's one of the bats that we caught when
we were in Belize.
Here's another bat we saw in these fantastic
limestone caves.
This was another bat we actually found after
a long night of netting (we got skunked, we
didn't get a single bat) and then this one
was roosting in the closet next to one of
our rooms.
This is a sac-wing bat.
Notice there's this little packet right here.
And this sac is full of pheromones.
This is a male bat and he has a harem - a
group of females that he protects - and he
uses the pheromones here to rub on his group
of females to claim them.
Here we have lined wing bat.
These guys were out roosting again over the
river that we were staying near.
I hope you've enjoyed this talk about bats.
Please don't hesitate to email me or ask me
in class if you have any more questions.
I think they’re amazing creatures and we’re
just at the tip of the iceberg of what we’re
learning about their biology and their ecology.
