What has eight legs and may be disappearing from Missouri's landscape?

Missouri’s tarantulas may be disappearing.

The Missouri Brown Tarantula, or aphonopelma haensi, is the docile species that lives in Missouri and for the most part can be found below the Missouri River.

The docile nature of Missouri tarantulas make them prime targets for people poaching them as pets, which is cause of concern for researchers like Becky Hansis-O’Neill, a Ph.D. student at the University of Missouri St. Louis who studies the spider.

Alex Cox: So, I’m not sure people think of Missouri when they think of tarantulas. Can you tell us a little about the tarantula population in the state?

Becky Hansis-O’Neil: So we only have two sites that are relatively small and they're not doing great there. We're getting at our highest numbers are a little under one tarantula per acre.

And if you go down to Texas, I found in the scientific research, that someone reported, like, I want to say 40 individuals in a residential backyard. That's way more than one acre. So the populations at our sites are low.

We're working this year to see if we can expand our search a little bit to see if that relationship holds throughout Missouri, or is it just a problem where we happen to be studying?

So long story short, I don't actually know. But we're we're looking. It's not it's not good. I think it would be better if there were more of them.

Alex Cox: So, you're saying because the tarantulas in Missouri are specifically docile, people are poaching them to sell as pets?

Becky Hansis-O’Neill: Yeah that's what we think is happening because we see lots of evidence of disturbance.

And the populations of the tarantulas at the sites where I work are much lower than we see in other places like Colorado, and Texas. So we think part of what's going on is people are probably taking them, they might not realize their populations are low, because this is not an endangered species.

Provided by Becky Hannis-O'Neil

That, because so we see when we're out at our field sites, we see a lot of displaced habitat, so logs, rocks, things like that, where people have moved them, and then not put them back.

People only usually do that if they're looking for reptiles, amphibians and vertebrates, when they're looking for animals. So there's a whole hobby called herping. But so it looks like people are out there herping. And sometimes people just take stuff home with them for the pet pet trade.

So, the genus that we have here, usually those aren't gonna be expensive. And by the way, MDC says, You can't buy them in Missouri, or at least you're not supposed to.

So, I'm going to qualify that. We see a lot of disturbance associated with these kinds of activities, where tarantulas or other animals would be taken. And then we have these abnormally low population densities.

So, that could be due to habitat quality or other factors. But just given that we're seeing so much habitat disturbance, we think it's probably people.

Alex Cox: So, how would this – OR COULD this poaching impact the larger ecosystem?

Becky Hansis-O’Neill: Yes. And this is something I didn't even personally realize because it's it's fun to look at bugs and lizards and things in nature.

But it turns out that if you're moving things around, you can have some really outsized impacts on the environment.

And if you look at a place like a glade a lot of the animals that live there lizards, snakes, tarantulas and their ectotherms are cold-blooded, so they rely on the Sun for heat.

So, there's going to be little places in the glade that we call microhabitats that are just right like Goldilocks that have the right temperatures and humidity for them. And this comes from researchers and Australia's, but what scientists find is if you move say a rock, and it's displaced, even 30 centimeters or less under that rock, it's cooler, and it's less humid.

So, when people are moving stuff around like that these micro habitats get degraded and they're less suitable for the animals that live out there on the plate.