Curbing the Threat of Invasive Species with Jacob Barney

(Music)

Travis Williams

What's your first thought when you hear the term alien invaders? If you're like me, it might be of spaceships and little green people coming down from the sky and us having to be defended by Will Smith and Randy Quaid. And while that can be a little bit scary, probably the more realistic threat to us all are invasive species of different plants and critters that find themselves in non -native areas. So I'm curious how we go about defining these invasive species, what bad things are they actually doing to our environments, and How can we help mitigate? And thankfully, Virginia Tech's Jacob Barney was kind enough to answer all these questions and more.

Jacob is a professor in the School of Plant and Environmental Sciences and the director of the Invasive Species Collaborative at Virginia Tech. We chatted a little about the history of the term invasive species. He broke down what exactly it is that makes their invasion so costly to our communities. And he shared some practical advice of things that you and I can do to help stop those problems from occurring.

And forewarning, just talk a little bit about a species of snakes that found their way into toilets, which was confirmed as one of my deepest fears. I'm Travis Williams, and this is Virginia Tech's Curious Conversations.

Travis

I think maybe a good place to start is simply what is an invasive species?

Jacob

Yeah, so an invasive species is any organism that has been introduced beyond its historic range through the actions of humans, whether intentional or accidental, and it establishes in that new range and causes some sort of negative harm whether it be to the ecology, the environment, or health.

Travis

Yeah, you mentioned that the historic range of where it grows historically is when it moves, can that be, like how specific, I guess, can the historic range be for species?

Jacob

Yeah, so the way to think about it is where a species has evolved over the natural course of its history.

And we often don't have specific geographic boundaries for a lot of species. We tend to think about them on country or regional or continental scales. And often we think about invasive species in that context as one from very far away. But that's not always the case. There are examples of species that have been moved within the United States, for example, that are native to some part of the country, but not native to others.

Travis

I guess what I'm curious about and the reason I ask about that range is because I'm curious if it's possible for like an invasive species to be in my backyard but not in my neighbors or are we so close that one would be the other?

Jacob

Yeah, that's a great question. So we typically think of species ranges in a larger context. So we might think about something that's native to the eastern United States just because it has that large native range doesn't mean it occurs everywhere within that geography as all species have evolved to reproduce and survive in specific types of environments. So they may be adapted to grasslands or wetlands or mountain tops. And so they can have what seems like large ranges that sort of over conveys where they actually occur in that geography. So it is possible that you could have something in your property that your neighbor doesn't have for a number of reasons.

Travis

So I guess we're talking about invasive species and just by the name alone they sound bad. Yeah. What makes them so bad?

Jacob

So there's an interesting history actually with the terminology of invasive and the language that's used in this field.

It actually dates back to post -World War II when there was an animal ecologist named Charles Elton and he was publishing a book on introduced species and the consequences they have. And he borrowed the language of the time of war and invasion and nativity and introduction. so that the concept of introduced species is not new. In fact,

Darwin noted species of European descent as he was sailing across the world. But it was really the publication of that book, post -World War II, that adopted that language of invasion. And it's got a little bit of a sketchy history as to the benefits that that provides, because it does convey a message of harm or being unwanted or causing some sort of undesirable damage, but it can also have unintended consequences as to the way that it may cause xenophobia, that all introduced species are undesirable. And that's certainly not the case. in fact, there's the, there's this statistic that only one tenth of 1 % of all introduced species actually become invasive. And so the vast majority of species that are introduced are not problematic and some are actually desirable. In fact, many of the plants and animals that we eat were introduced from elsewhere.

Travis

That is fascinating context for just the time alone. And it's interesting how language evolves like that.

Jacob

I can give you some examples of like the kinds of impacts that invasive species have in sort of a larger context just to establish that.

Invasive species are those introduced species that do cause some sort of undesirable harm. There was a first of its kind publication last year called the IPBEST report. You can think of it as somewhat analogous to the IPCC reports on climate change. This was the first global synthesis on effectively everything we know about invasive species in a global context. And there were some really important statistics that came from that. And this was a synthesis of something like 10 or 12 ,000 published papers across the history of the field. And there were estimates that invasive species of all kinds have an economic consequence of about $423 billion a year, which is substantial, though I would sort of put an asterisk that that's probably grossly underestimated.

I suspect we just don't have the data on the economic impacts, but we do know that they're very costly. And it's estimated that they cost the Virginia economy about a billion dollars a year. And again, that's probably an underestimate. Another notable statistic is that invasive species are responsible for greater than 60 % of all extinctions. And that was a really eye -opening new insight because we had previously thought that habitat destruction was the leading cause of extinction. It turns out invasive species actually are.

Travis

Wow. Those are both fascinating. I guess to follow up that, that money that's attached to how much invasive species are causing people, what does that generally spend on? Where is the cost generated?

Jacob

Yeah. see, I think put it in a couple of different bins. One would be the money that's spent on managing the invasive species. So that could be through people, hours, equipment, pesticides, prevention strategies, scouting, all of those. And that's really expensive. The other would be the impacts to the economy through lost tourism or trade or production of fisheries or some of these other industries that are impacted by invasive species. And the shipping industry in particular is one that has suffered a lot of consequence from invasive species in that they've had to adopt new sanitization schemes because historically when big tanker ship would go from port to port, they would take on in the old days soil and rocks to keep the ship upright in the seas. And then they switch that out for water, but it turns out that's picking up a lot of seeds and organisms. And then when you get to the new port of destination, they would empty that out and accidentally introduce all kinds of organisms. And so the industry recognized this as a problem and adopted this international strategy where the ships would take on new water in the middle of the ocean, dump out the old water, sort of swish their tanks around because it's extra salty in the ocean compared to the shores. And that would be a way to sort of sanitize it. That's been a really effective way of mitigating invasion due to shipping. But you can imagine how costly that would be.

Travis

absolutely. And then I guess on the extinction side of things, do invasive species cause other species to go extinct just because of resources that they take up? what drives that?

Jacob

Yeah, there's a number of mechanisms that that happens. I think one of the most famous examples, and we've got some faculty here on campus working on this, is the brown tree snake that was introduced accidentally to the island of Guam in World War II. And the Guam ecosystem has no native snakes. And so the birds and the lizards there had not evolved any fear of snakes. There was no competition and abundant food, and so these snakes reproduced and basically ate through almost all of the birds and lizards on this island. And so now the whole ecosystem has lost a whole trophic level of organisms in response to this invasion. my gosh.

Travis

Well, thankfully, I think my fear of snakes has evolved quite a bit. And you didn't make it go away just now. So yeah, for that.

Jacob

There's these terrifying pictures of snakes coming out of toilets and falling off electrical lines and all kinds of things. Pretty scary.

Travis

I think a snake in the toilet is one of my deepest fears.

Jacob

so for good reason.

Travis

Yeah. Well, I'm curious, I know it does sound like it's a huge problem. What are some of the challenges as far as going about maybe tackling this problem?

Jacob

Yeah, there's a number. One of them is just the sheer diversity of the kinds of species that are invasive. Everything from microorganisms and viruses to plants to hogs to birds, the sort taxonomic diversity makes any single solution unlikely. And then the second piece is the number of ecosystems that invasive species occur in, which now is every continent, including Antarctica, has been invaded. And so again, that diversity of location makes it very difficult. And some of the others is there are, they're continued to be intentionally introduced species that are known to be invasive and that could be through the horticultural trade that you can still go to a big box store and buy plants that are known to be invasive. Even here in Virginia, there are folks who still are really into exotic pets and the exotic pet trade has been a source of introduction, including the Burmese python in the Everglades, which is sort of a famous example of somebody who thought they were doing the right humane thing when their snake got too big in the home, they dumped it out in the Everglades and now those snakes have reproduced and eaten almost every mammal in the entirety of the Everglades. And so that sort of diversity of species and ecosystem and pathway makes any single solution is very challenging.

Travis

Yeah, it sounds like it's both a little bit of scale and diversity, but also some some cultural awareness as far as changing maybe the way people, the people operate.

Jacob

There is and I think that's a that's a place that I think there's also really opportunity where we can all play a role in mitigating invasion by educating ourselves on what we buy and plant in our yard, the kinds of how to maintain our pets and the kinds of activities that we pursue. So simply cleaning your hiking boots before you go from place to place or not transporting firewood from one place to another can have really important consequences on mitigating invasion. And you mentioned this when we began that you lead this invasive species collaborative.

Travis

I'm curious what types of work you all are doing and really who makes up that group.

Jacob

So we are a group of faculty, students, postdocs and staff who are from all over campus and we are really interested in the interdisciplinary aspects of invasion and identifying what makes something invasive to generating new management strategies to the socio -ecological dynamics of invasion and ultimately are we able to synthesize all of this information and give new policy for ways of mitigating invasion. we are a newly supported destination area here on campus and that has allowed us the unique opportunity to have some funding to support the activities that we're doing, but we're also hiring seven new tenure track faculty in four different colleges all across campus who are all going to work on something related to invasive species.

Jacob

Why do you think that it is so important to take such an interdisciplinary approach to this topic? I think this is, this is one of those problems that, that I think really effectively encapsulates the, the kind of problem that can't be solved with just pure science or the social science or a policy measure. really takes sort of what we've called the broadening of the tent is people from all disciplines and dynamics working together because I can do great ecology, but if the citizens of a place aren't interested in it or aren't engaged in that conversation, they may be less likely to adopt those practices. And so having the social sciences engage with the natural sciences and working across colleges and domains is really the only way to meet this moment and this problem on the scale that it requires.

Travis

Okay, so you've been at Virginia Tech now for 15 years working in this space. What has been the greatest change or shift that you've seen in your time here? A

Jacob

 couple things I'd say from the broader perspective there's tremendous public interest in knowledge on this topic that I think is really beginning to shape the broader context for this this topic. We've gone from you know, this being sort of a somewhat newish niche feel to one that the public really cares about. the, I've engaged with stakeholders all across the state who are really passionate about making a difference in this space. And that has, I think, reflected back on the university who now, you know, is investing in this topic because they recognize the role, the importance of this topic, both locally, regionally, and globally. but also the unique role that Virginia Tech can play here in the type of breadth and depth of knowledge that we will bring once we have the full strength of the invasive species collaborative that we can make a real difference in this space. Yeah, and you mentioned earlier something, you mentioned earlier that a person going back from hiking should clean off their boots as one tip.

Travis

What are some other just very basic things that I can do, to not bring any invasive, specifically snakes, but any invasive species into my life or into this region?

Jacob

So I think there's a few real basic things that everybody can do. First and foremost is gardening is one of the number one hobbies in the country. myself am a long time avid gardener and

Being educated as to what is in your yard and what you're bringing into your yard is a very easy first step. And there are a lot of resources available. The Natural Heritage Program here in Virginia maintains a list of known invasive species. understanding what you're bringing into yard is very, easy. Thinking about adding more native plants to your yard to you know, replace some of the introduced species perhaps, but also bringing pollinators in and all of the various benefits that that brings. If you're a fisherman and you enjoy going and doing that activity, live bait is actually one way that invasive species have been introduced. So being responsible with your bait when you're done fishing and not dumping it in a water body is a great, very easy thing to do. Being a responsible pet owner is another great, very simple thing to do. One species that is maybe underappreciated, especially in United States, as being one of the most impactful invaders globally is the cat. It's the house cats and feral cats are one of the most costly, damaging introduced species globally. And that has to do with hunting native birds and all of the activities that just normal cats do. So, you know, thinking about keeping your cat inside and, you know, for any of your pets, you know, just being a responsible pet owner would be one way to think about, you know, mitigating unintentional reproduction and population growth, but also harm to the native songbirds. So those are just a few really basic examples that we can all participate in.

(music)

Travis

And thanks to Jacob for sharing his expertise related to invasive species. If you or someone you know would make for a great curious conversation, email me at traviskw at vt .edu. I'm Travis Williams and this has been Virginia Tech's Curious Conversation.