Reader Joe Dickinson sent some photos of a big passel of bats (what’s the correct term?) living under a road that I drove on often when I lived in Davis, California. I had no idea there were bats there! Joe’s notes are indented:
We recently attended a Bat Talk and Walk at the Yolo Bypass Wildlife Area between Davis and Sacramento, CA. The I-80 freeway crosses a wetland (and rice fields) on an elevated causeway, and about a quarter of a million Mexican free-tailed bats (Tadarida brasiliensis) roost under it during the summer. [JAC: This is the same species that roosts under the Congress Avenue Bridge in Austin and goes out en masse every night as hundreds of tourists and locals watch.] There is a very entertaining and informative talk, using rescued animals and videos to show details of anatomy and behavior. Then, an opportunity to watch the mass emergence of foraging bats right about sunset.
Here is the setting:
Bats start to emerge.
Soon, there is a continuous stream.
Then the sky is filled with bats making fantastical, constantly shifting patterns.
Meanwhile, groups of Canada geese (Branta canadensis) are moving into an adjacent field, creating their own shifting patterns of silhouettes. Altogether a great experience.
Here are two pictures of this lovely creature from the Web; you can see why they call it “free-tailed”:
A cloud of bats.
A mobile of bats?
Cool! We still haven’t confirmed any bats in the bathouse on our home. 🙁
The bats locally have been having a really hard time with Whitenose Syndrome.
Like the birds with West Nile Virus, we are hoping they’ll come back soon.
Quite a few haven’t come back my way – crows especially.
I used to enjoy watching the local bats but white-nose disease has apparently wiped them out.
We still see a few at night in the Minneapolis area; but there are far fewer of them.
Nice work
I saw bats in our yard – NY – for the first time in a long while. I hope the population is recovering.
I hear them overhead in my backyard if I’m out there at night. Good bug eaters! It’s Little Brown Bats here.
I love bats, but they do make for rather frustrating subjects to observe, they being fast flyers and nocturnal, and I without a mist net (or permits). Still, watching their silhouetted forms flying past the deck overlooking the Lake of the Ozarks at my family’s home is lovely and relaxing. Thankfully, Missouri hasn’t see a huge population crash since the introduction of white-nose, at least not in the species I routinely see. I know it primarily harms the ones that congregate in large numbers, rather than those that roost/hibernate singly or in small numbers, which may explain my lack of noticing any measurable impact thus far. Here’s hoping a speedy mutation event that tempers the syndrome…
Lovely pics, all.
A mercurial murmuration?
Beautiful pics. I’d love to see a swarm like that some time. I’ve only ever seen bats singly or in small groups.
A group of bats is called a “colony”. Bat facts!
While roosting it certainly is a colony. It seems a large number in flight deserves another, more evocative term. I like the “cloud” suggestion.
The Princeton Encyclopedia of Mammals uses ‘colony’, and says:
Though that may be meant to be more scientific than poetic, as many collective nouns are.
Wikipedia claims ‘colony’ as the collective noun, referencing an old USGS site. However, that just gives ‘band’ for gorillas, instead of the much funnier ‘whoop’ or ‘flange’ – which is my standard for whether a list of collective nouns has really kept up with the times:
Totally cool! But as Tom Lehrer sings in his song about Santa and his reindeer sleigh:
‘Don’t stand underneath when they fly by’.
I love bats. When I was in Cairns, I loved going and watching the Flying Foxes in the trees eating fruit.
I love bats too, but I’ve never seen one in real life. This post has given me a bucket list activity!
Hmmmm… No bats in NZ? Seems unlikely.
Oh, wait…*googling*…”Bats are New Zealand’s only native land mammals. There are three species: the long-tailed bat, the lesser short-tailed bat, and greater short-tailed bat. … The endangered lesser short-tailed bat is an ancient species unique to New Zealand and is found only in a few locations.”
Keep looking.
There are bats here, I’ve just never seen them. Our only native mammal is a bat. I love the idea of seeing all those bats flying around like starlings, which is why it makes it to the bucket lost.
The NZ lesser short-tailed bat is basically terrestrial and forages on the forest floor. Intriguing, evolving to be a terrestrial mammal? (Btw. I note too that kiwis are the most mammal-like of birds).
Sadly their terrestriality makes them vulnerable to predation by introduced aliens. IIRC their status is ‘threatened’.
I don’t know much about the bats.
There are five species of kiwi. I don’t know the details of all of them, but they’re all endangered to some degree, and the rarest is critically endangered. There are, naturally, conservation programmes for them all.
In NZ,birds Film the mammal niche. Introduced species are a blight on them though, as you point out.
I’ve never seen bats in NZ either. I wonder how they got here, since we’re 1200 miles from Australia. Seems an awful long way to fly.
cr
They took the bat mobile. Ba dum dah! tish!
🙂
Norfolk Island is a possible waypoint on a flight from AU or the islands to the north.
Gould’s wattled bat (Chalinolobus gouldii) is indigenous to Norfolk Island. Depending on air currents, I suspect it’s possible for them to fly that far.
600 miles? Are bats that efficient flyers? I did think of Norfolk Island but it’s a very small target to hit after 600 miles.
But then, obviously, the bats got here *somehow*.
cr
Another means of transportation is a ride on flotsam and jetsam at the ocean surface. A free ride where the currents swirl. However, no other mammals seem to have made the trip, so probably flight is the answer.
What you have to do is stand outside at night, raise your hand up above your head with the back of your hand pointing toward the sky, then call, “here batty batty batty bat!” 😀
I think that’s right. Except the “here batty batty batty bat!” might be a little provocative. I usually just wiggle my little finger. They pick it up on sonar. 😎
Bats are critically important to our planet!
LOVE A BAT!
Sadly, I see no bats in my yard this evening. In past years, I’ve watched a bunch every evening over the house (central New York) feasting on flying insects. I want to see them again before I die, or Trump is elected whichever comes first.
Great photos of a beautiful scene.
I put out a bat-box at our new house. I don’t think any are living there (yet). But even if they do, I don’t think I’d be able to tell. Maybe some night vision goggles would help, but I don’t own any.
You could put up a motion sensitive infrared camera, pointed at the bat-box.
That’s some good thinking…thanks!
Apart from being as great post I’ve learned that some bats don’t necessarily fly in a straight line.. local rules apply? some bat up front sneezed?
My previous “up close and personal” experience with bats occurred when I was making a modest addition to a cabin we had in the mountains of Utah. I put up a temporary covering of cheap tar paper when winter was about to catch me with the project unfinished. The next summer, I pulled that off to install a more permanent covering. Well, several bats had wedged up under the loose lower edges of the tar paper to roost. They flew out as removed it. A bat in your face when you are 20 feet up an extension ladder is a memorable encounter.
The birds are impressive!