I’ve always taken cactuses for granted — I’ve lived in deserts before, and they’re just there, growing all over the place, and familiar part of the landscape. I didn’t think about the fact that they’re an entirely American clade, or that they could be a destructive invasive species elsewhere. I didn’t know that they were a major pest in Australia, along with rabbits and cane toads (Australians keep bringing in alien species that devastate their ecologies, in desperate attempts to counter the previous wave of invaders). So this was an informative video for me.
It’s also an example of where bringing in yet-another-foreign species, in this case moths and scale insects, defeated the problematic invasive species. For now.


We export alien species that devastate ecologies too. How are those fire prone Eucalypts doing in California ?
They did the same thing in South Africa before they did it in Australia.
Prickly Pear cactus was introduced into South Africa in the 1700s. It became an invasive species and took over many areas. They ended that problem in 1932 by introducing insect predators.
I’ve eaten the fruits of Prickly Pears before, harvested from wild plants.
They are very good.
Hmm…the biggest invasive species from 1492 onwards has been Europeans. People descended from my country seem especially prone to become bigoted christians or far-right conservatives with destructive consequences for the land.
(With exception for the guy who built the Monitor, he was great)