Invasion Ecology and Horizon Scanning for Invasive Organisms

(graphic rattling)

(graphic clatters) (computer mouse clicks)

- Hi, Sanford Smith here with Penn State Extension.

Today I'm joined by Deah Lieuance, and she's gonna talk a little bit about invasion ecology.

This is her specialty, as well as horizon scanning.

Now, I suspect that many of us don't know too much about this, so listen up, Deah, what is invasion ecology all about?

- Invasion ecology is the study of ecosystems and the addition of new species that are not native to the area.

So for example, a plant or an animal comes into your ecosystem and it uses resources in a different way.

Well, that's gonna change the way the ecosystem interacts.

And so what we wanna do in invasion ecology is understand those processes and use that to try to help in prevention efforts and to do better with our management techniques.

- Yeah, and in fact, we're standing in the major ecosystem of Pennsylvania in the Northeast, it's forest, and right behind me is a very interesting example of invasion ecology, those big shrubs that you see, they're all non-native invasive shrubs that have come in here like honeysuckle and privet and euonymus, and they've displaced the native plants.

Okay, so that's invasion ecology.

Let's talk a little bit about horizon scanning.

It makes me think of someone sort of looking on the horizon, but what does it mean in regards to invasives?

- It's not quite that exciting.

What we do is we take a bunch of information and try to process that to identify threats to our ecosystems.

So for horizon scanning for invasive species, what we do is pull a list of species that are not in the area of concern.

So in this case, in say the Northeast.

And we wanna evaluate those species for their invasion risk.

So we look at the likelihood the species will arrive, the likelihood that it will establish and spread, and the consequences of that.

What are the impacts, the negative impacts.

Part of the process is, and what makes a horizon scan successful is to build a big working group of people, researchers, practitioners, taxonomists, regulators.

You wanna get a nice diverse group that think about these species in different ways so we can have their perspectives brought into that scan as well.

And so we take the, those scores and we rank the species and at the end we have a rank list of invasive species threats that can be put on watch lists or could potentially be looked at for regulation to try to keep them from being introduced.

- Let me stop you right there and ask a question.

Is it cheaper to just go out and spray invasives once you have them or would it be cheaper to try to prevent them from getting in here in the first place?

- It is absolutely cheaper to do the prevention.

There's a lot of data coming out now about how much money is spent on management versus prevention, and they've shown that the best bang for your buck is to do that prevention side where, for example, for every dollar spent on prevention, you get about a $25 return on investment.

But when you get on up into that maintenance control where you're just trying to keep a species, you're spraying, trying to just keep it down as much as you can where you're only getting about a one to 1 or a one to $5 return on that investment.

So it's really, the best approach is to do that prevention.

- Right, and lots of times that control work you do isn't a hundred percent effective, you have to go back and do it again and such so, yeah.

So let me ask you a couple more questions.

So we're talking about all types of organisms, aren't we?

It's not just plants? - Mm-hmm.

- So what does that include?

- So it depends on your horizon scan, but some horizon scans are all taxa.

So one that we completed for Florida included your plants, your vertebrates, and your invertebrates.

Some can be taxon specific or just your plants.

We currently have one that we just started for the Northeastern region to try to predict which forest pests are going to shift with climate change.

Thinking about the example of southern Pine beetle and what it's done up in the Northeast to those trees.

- So what is it that really jazzes you about this kind of science?

- I really find the prevention piece to be the most rewarding because it really feels like you're doing something.

You still have to do that research in the greenhouse, in the field, to understand the organisms to be able to do those predictions.

But to do one of these horizon scans and see your list get used to actually try to stop some of these species from entering was really rewarding.

- Thank you very much Deah for joining me today.

And thank you folks for watching this video.

We will catch you again next time.