Tag Archives: non-native

When Is A Fish Really Native?

Image Credit: Alexandre Roux, CC BY-NC-SA 2.0, Image Cropped

Image Credit: Alexandre Roux, CC BY-NC-SA 2.0, Image Cropped

In the summer of 2019 I spent a week driving around south-east Norway with my Master’s student Bastian. The plan was to speak to local freshwater managers and get their take on invasive fish species in Norway. I’d never conducted this sort of research before, but I thought I knew what I was in for. Invasive bad, native good, right? More nuanced approaches are for those who are disconnected from the problem, academics like me who could watch from a distance and comment airily.

First interview. What does the term “invasive species” mean to you?

Obviously I expected some combination of “alien to the region”, “brandishes halberds and horned helmets” and “outcompetes the native trout” (trout and its fellow salmonids are really quite popular here). What I got instead (abridged) was a contemplative shrug and a reminder that there are almost no native populations of trout left anywhere in Norway.

Insert confused ecologist.

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Investigating the Financial Costs of Invasive Species

Economic costs of biological invasions in the United Kingdom (2021) Cuthbert et al., NeoBiota, https://doi.org/10.3897/neobiota.67.59743

The Crux

I write near constantly about non-native species on Ecology for the Masses, but I mainly focus on the negative impacts that many of them have on native ecosystems. Yet often if we want to really kick off initiatives to manage invasive non-native species, we need to point out the financial burden that many of them bring.

Yet obtaining a simple monetary estimate for invasive species is not easy. A few particularly notorious invasives tend to take up a lot of research focus, which mean that there are many species out there for which our cost estimates could be unreliable. Likewise, we’re likely to have a better picture of the impact of non-native species which have been established longer than ones who have just arrived, and haven’t been sufficiently studied or haven’t spread far enough to have had a measurable impact.

But non-native species aren’t slowing down in their spread anytime soon, so it’s important to figure out what the costs of invasive non-native have been and will be, as well as where there are holes in our knowledge that need to be filled. That’s what today’s study set out to do, by looking at invasive species in the United Kingdom.

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