- ED LEBRUN: Sweeping up dead ants every day.
Millions of ants inside their house.
Ants getting into the electrical equipment
and then the electric circuit shorts out--
Just much, much worse.
- NARRATOR: The script is familiar.
An exotic ant invades,
wreaking havoc.
But these are not fire ants,
and this is not a horror film.
- FILM NARRATOR: There is no word to describe THEM!
[scream]
- NARRATOR: Yet like the movies, native species
battle for survival.
There is public alarm.
- FILM NARRATOR: Stay in your homes!
- NARRATOR: And scientists race to combat the menace.
This is one crazy ant.
- FILM NARRATOR: I tell you gentlemen, science has agreed--
- NARRATOR: The tawny crazy ant,
native to South America,
was first documented near Houston and in Florida
in the early 2000s.
Since then, it has invaded around the Gulf Coast.
- They are found in a variety of habitats--
urban, suburban and also in natural environments.
In Texas, we know that when you get an invasion of crazy ants,
you lose lots and lots of insects,
and you also lose all the ants except for a few small species.
- NARRATOR: Researchers, like Ed LeBrun, are concerned by
the impacts of crazy ants on natural systems,
even in the suburbs.
- ED: Yeah, they are very active today.
They cause a lot of damage to the native ecosystems
by greatly reducing abundance and diversity
of other insects in the system.
- NARRATOR: And some natural places are especially fragile.
- ED: This many ants in any environment will have
negative consequences, typically,
but there's a lot of endangered species in these caves,
right Todd?
- Yeah.
- NARRATOR: At the entrance of a protected cave on the
outskirts of Austin,
LeBrun and Natural Resource Specialist, Todd Bayless,
know swarms of crazy ants on the surface are bad news
for rare cave bugs below.
- We got a call from Texas Cave Management Association
to tell us that there was a major infestation of ants
that they'd never seen before in their cave,
and sure enough, found this tawny crazy ant in huge numbers
inside the cave itself.
That was a concern to us because this is one of the caves
we hope to protect for some species of concern.
We knew that they had the potential of being found
in other endangered species caves nearby.
[cave crawling]
- Onward and inward!
My name is Travis Clark, I'm a Natural Resources Specialist
for Travis County at the Balcones Canyonlands Preserve.
The BCP was created to provide protections for
eight endangered species,
six of those are karst invertebrates.
We're at a cave in South Austin that's been impacted
by tawny crazy ants.
And the reason we're entering today is to do one of our
quarterly karst faunal surveys to assess impacts
by tawny crazy ants.
There he is right there.
- MARK SANDERS: This is one of the species of concern that
we're trying to protect.
The species name is Rhadine Austinica.
- TRAVIS: The species are essentially canaries in a
coal mine, and so they're going to be indicative of cave health.
These cave systems are important because they're
recharge features.
People benefit through drinking water, through recreation
where this comes out in springs.
- MARK: Cicurina Bandida.
- And that was two?
- One.
That's it.
- TRAVIS: So essentially what we're charged with is providing
all the safeguards we can for these caves.
- TODD: The underground ecosystem is very unique,
not just in North America but all over the world.
Knowing we had a problem, we looked for experts in the
ant community that could possibly help us out
and we found Ed LeBrun over at UT's Brackenridge Field Lab.
- ED: This is the invasive species research group at the
University of Texas at Austin.
And we are working on a lot of invasive species problems
in the state of Texas.
Most people in Texas, when you're talking about
invasive ants are thinking about red imported fire ants.
They actually do less harm to the native Texas ecosystems
than these crazy ants do.
- NARRATOR: Crazy ants, so named for their
erratic movements, eat or outcompete most of the spiders
and insects around them,
including the formidable fire ant.
- Fire ants are very tough.
They have this extremely toxic venom.
She actually goes up and literally takes the
venom droplet off the end of the fire ant stinger.
And crazy ants, they go, they fight, they get hit with
fire ant venom, they just keep fighting, they keep
charging in and they should all be dying.
And so then here's the crazy ant detoxing from the venom.
People when you tell them they displace fire ants,
it's like, "Yea!"
But the net effect if very negative.
Insects are the base of the terrestrial food web,
so if you knock out the base of the food web,
those impacts then spread throughout the
rest of the system,
like birds and reptiles
that feed directly on the insects,
which plants proliferate and which plants don't,
so you can really change the whole system
by altering the arthropod community.
Here's a trap.
- NARRATOR: Such threats have biologists searching for ways
to control crazy ants.
Texas Parks and Wildlife contributed funding to an
early investigation of boric acid bait stations
in the field.
- Unfortunately, it's not very promising.
- We discovered that, although the crazy ants loved the bait,
brought the poison back to their nests,
that it just didn't reduce the densities of the ants
that we were hoping for.
- NARRATOR: In the lab, there is now hope for a
natural enemy that some crazy ants already carry.
- ED: These are uninfected ants, so these were our control ants
in that experiment.
The microsporidian that we're working on is showing
quite a bit of promise.
- NARRATOR: A fungal parasite specific to these ants
could help keep them in check.
- The development of larvae to workers is greatly reduced
by infection, and the life span of workers is reduced
by about a quarter.
There are these phydolese, solonopsis, dipoloptrims,
they are very tiny.
And most of your ant diversity is down at this kind of size.
Tawny crazy ants are just a very small component of the
overall ant assemblage down in Argentina.
- NARRATOR: The world of ants...
- ED: Leaf-cutting ants...
- ED: ...we have here in Texas as well, we have
- NARRATOR: So further studies of ant interactions,
where crazy ants are native, and where they are not,
may provide more ways to minimize their impacts.
- FILM NARRATOR: The subterranean nest,
where the beast spawns its terrible progeny.
- NARRATOR: Meanwhile, we should remember that the
very best solution to invasive species problems
is to avoid creating them in the first place.
- ED: Crazy ant queens don't fly.
What that means is they don't have a way to infest new areas
except for people moving them.
And that's unfortunately what's happening all over the state.
So, people move them when they take a potted plant somewhere
that has ants in it.
When you go to a garden store to buy something,
it's important to look for ants.
I mean you don't have to be an ant biologist,
just look for ants and if they're covered in ants,
don't buy it.
Recreational vehicles are a problem as well.
Being sure that there aren't any ants in your vehicle
when you go to visit a new place.
[door slam]
[intriguing music]
Species invasion,
it's a natural process, right?
Species have been moving around the planet
since there's been a planet.
The problem is, humans with our commerce and everything we do,
elevated the rate at which these invasions happen
by many orders of magnitude.
And so the natural system doesn't have time to adjust
before the next invader comes.
The natural systems are very resilient.
If you can give them time to adjust,
they will.
We should be paying attention,
and we should be investing resources
in offsetting the impact.
That's why I work here.
That's what we're about is trying to change the dynamic
so that we can preserve the natural systems that we all
grew up with.
[intriguing music]