Bias Against Introduced Species - We Couldn’t Have Said it Better Ourselves

The essay discussed in this post can be found here:  https://aeon.co/essays/ecologys-war-on-invasive-species-isnt-science

We at Alley Cat Rescue love the new essay “Conservation Prejudice” by science philosopher, Carlos Santana. Santana bravely argues against the common presumption that a non-native species has a harmful effect on an ecosystem. And then he exposes the “double standard” that most conservationists have in how they think problematic introduced species should be dealt with versus problematic native ones.

Santana reveals the truth that many introduced species are blamed for the decimation of native wildlife and plants and labeled “invasive” without scientifically gathered data to support those claims. Citing the findings of biologist Patricio Pereyra et. al, Santana writes, “how a species is framed in the scientific literature is independent of evidence of harm. An alien species we know little about is just as likely to be framed negatively as one that has been implicated in driving extinction.”

Santana terms this tendency “nativist bias” and (we were happy to see), he illustrates nativist bias with the example of Australia’s treatment of cats and foxes:
         "For instance, the majority of Australia’s modern mammal extinctions are usually blamed on invasive cats and foxes. The biologists Arian Wallach and Erick Lundgren recently went looking for the data that supports this view, and found that, for 70 to 80 per cent of purported cases, no such data exists."

This echoes what Alley Cat Rescue has been saying for a long time; we don’t have the data to judge the effect outdoor cats have on most prey species, and therefore environments, around the world. In some cases, an introduced species may integrate into an ecosystem and have a positive impact on that ecosystem. That proved to be the case on both Marion Island and Macquarie Island, for example, where the cat populations were culled through great expense over many years only to result in an actually problematic explosion in mouse and rat populations.

In addition to his logical arguments in favor of data-driven assessments of the impact of introduced species, Santana presents a moral argument against culling nonnative populations - even those that are proven to be harmful in some way. He brings up the excellent point that people do not extend the same compassion to invasive species that we do to troublesome native species that cause conflict.  When native animals threaten local agriculture, for example, conservationists devise humane ways to mitigate the human-wildlife conflict. On the other hand, nonnative animals are more often added to target lists and killed. Yet the cause of every one of these situations is human expansion. The animals, no matter their location of origin, are blameless.
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We encourage all critical thinkers to read Carlos Santana’s essay. And if you know someone whose horizons it might expand, share it with them! Cats and other persecuted species need more allies!