> When does an introduced species become a native?
Well take the Australian dingo as an example.. The dingo was
introduced by aboriginal people to Australia 2,000 to 3,000 years ago
and, while largely accepted as a native species now, it's still a bit
of debate about it.
Against it being native:
Message: 1.
Subject: it was introduced by humans
Message: 2.
Subject: only a few thousand years ago
Message: 3.
Subject: it lives in places other than Australia
Message: 4.
Subject: it has done untold environmental damage (considered largely
responsible for killing off the "Tasmanian" Tiger from mainland Australia)
Message: 5.
Subject: It's not a marsupial, like the rest of the mammals around here
(apart from bats)
Message: 6.
Subject: it has been partially domesticated
For it being native:
Message: 1.
Subject: It was introduced by the indigenous people, which somehow people
may consider more "natural" than if Europeans did the introduction.
Message: 2.
Subject: It was introduced a long time ago (2000+ years)
Message: 3.
Subject: It's an iconic Australian animal
Message: 4.
Subject: It's only partially domesticated
Message: 5.
Subject: It has become an important part of the ecosystem, keeping out
smaller, introduced predators such as foxes and cats, and so allowing
Australian natives to thrive. (It had once been assumed to be harming
native populations)
So, is the dingo native? Mm.. kinda, yeah.
Is a dove introduced 200 years ago native? hmm..
The question is more than academic though. Dingos are now being
reintroduced to areas for their ecological role. But are cows native
now? Some cattle farmers are arguing that their cows should be allowed
through red gum forests of Barmah because they've been grazing there
so long that they've developed ecological relationships with the
natives. However one look at the the devastated areas compared to the
recovering no-grazing areas tells you that the relationship is very
one way.
Anyway if there's an official line between exotic and native, I don't
know it.
Peter Halasz.
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