Meanwhile New Zealand looks at Australia, pulls out their own biosecurity system and says "That's not a biosecurity system. That's a biosecurity system.
NZ is the only country I know that makes you take your shoes off in the airport... in order to scrub and bleach them (to be fair they were hiking boots, though not obviously filthy). What service!
True, but NZ has also learned it the hard way. There was once a vibrant birdlife in the South Island, especially. There is some early settler who said that the morning birdsong in Queenstown was deafening. Cats, introduced by European settlers, killed off a lot of the native birds, and the ecosystem is only recently hobbling back to normal (have done birdwatching in NZ).
If you are interested in bird conservation in NZ, please visit Karori park in Wellington and contribute.
BTW: some parks in US also have installed brushes to wipe your boots for preventing the transmission of invasive species seeds. I think there are a few in Wisconsin that I remember.
Some preserves in California have trays of disinfectant to step through, specifically for Sudden Oak Death. It’s a pathogen transmitted through dirt, so in the very few places that aren’t affected yet it’s hard to keep out.