Dams like this change the flow regimes of rivers, and prevent some species from accessing their spawning grounds, lowering population viability. But is removing them completely danger-free? (Image Credit: Notorious4Life, CC0 1.0, Image Cropped)
Category Archives: Invasive Species
Last Monday, I wrote about how climate change can facilitate the spread of non-native and invasive species. Today, we look at a species that whilst problematic now, could spread further throughout Norwegian waters as temperatures rise.
The last time we looked at an ocean-dweller in this series, we saw that while some species may not be great for ecosystems, they can provide an obvious benefit to other aspects of the region, in this case the fishing industry. The Pacific oyster (Crassostrea gigas) was also introduced intentionally for cultivation and is now on the verge of becoming a major problem in Norwegian waters.
In this series, we’ve looked mostly at species that have been introduced at defined points in time. The Pink Salmon and the Red King Crab were introduced into Russian waters near Norway in the 50s, the Canada Goose was brought to Europe in the 30s, the Sitka Spruce in the late 1800s. But with the onset of climate change, warmer conditions in the Arctic and sub-Arctic mean that the doors will open for more gradual arrivals. So let’s look at how climate change will facilitate the arrival of these newcomers.
Building on last week’s article on defining invasive and alien species as well as the work of Professor Mark Davis, I am going to do the unimaginable for an ecologist and argue that maybe alien species aren’t always a bad thing. I want to emphasize that maintaining biodiversity is essential, but maybe we should focus on the role of species in their environment rather than their place of origin.
Once again, let us talk about trees. Do not be fooled by their innocent appearance – that is exactly what they want! In reality, they can be just as problematic as any animal species. This week I takes a closer look at the Sitka spruce (Picea sitchensis).
Two weeks ago, Norwegian Science Institute Artsdatabanken (ADB) announced that they would be changing the name of their invasive and alien species index. Formerly known as the Black List, the institute decided to use a name with less negative connotations, “Fremmedartslista“, loosely translated, the Alien Species list. Given this series’ focus on species from that list, it seems like an appropriate time to look at how we define the terms ‘alien’ or ‘invasive’ species.
If you’ve read some of our previous posts on invasive species, you’ll have learned that they can be a real danger to local ecosystems and economies, and even have impacts on our health. But as Vanessa Bieker writes, there is a silver lining, and that comes in the form of what invasive species are teaching us about evolution.
Image Credit: Michelle Pemberton, The Children’s Museum of Indianapolis, CC BY-SA 3.0, Image Cropped
“… a red army of monster crustaceans – marshaled by Soviet-era leaders – is threatening to invade Western Europe …”
– James Owen, National Geographic, 2004
Ominous. That’s the thing, isn’t it. Some invasive species look harmless. You can’t be scared of a baby Canada Goose, can you? Or a nice purple garden flower. Such florescence. You can, however, be scared of a spiny, alien-looking 10 kilo mass of spines and pincers that has been shuffling its way into Norwegian waters over the last half-century.
In my previous posts on rewilding and wild boar, I talked about the effects of reintroducing species that were previously found in Norway. Now, I want to talk more about the large carnivores in Scandinavia which serve as protection against invasive species. This opinion piece is coming from an ecologist and a foreigner, so treat this like a Scandic breakfast buffet and take what you want.
Image Credit: Sue Sweeney, CC BY-SA 3.0, Image Cropped.