New Zealand was one of the last places on earth to be colonised by humans, only about 1,000 years ago. Using some fairly exciting new tools, such as paleoecology, scientists can now make pretty clear statements about what was here before humans arrived, and what happened after humans arrived. What happened was nothing out of the ordinary, just major transformation of habitats, in this case through altered fire regimes, and the introduction of many new species, some of which have gone on to become invasive. Ever since, New Zealand has lived the legacy of these impacts.
The introduction of mammalian predators to the islands of New Zealand caused the same impacts they had on all other islands – drastic reduction, it not outright extinction, of naïve native species. New Zealand responded boldly by pioneering the eradication of these predators from islands, larger and larger with each passing decade. The eradication of these predators is not about whether they are native or not, but about the damage they cause. These efforts are not about winding the clock back to a time before New Zealand was colonised, but about saving what is left of original New Zealand today.
Could we reach zero invasive predators on the main islands of New Zealand? In the May issue of BioScience, with colleagues from Landcare Research, we discuss the biological research, technological advances, social capacity and enabling policy that would be required to theoretically eradicate introduced mammalian predators from the entirety of New Zealand. Is this even possible? Perhaps as much as flying to Mars isn’t today, but will be one day. Is this economical? It turns out very much so, when casting a fine lens over the accountant’s national balancing book. The entirety of New Zealand could become the first conservation country. We also believe other nations with substantial island estate should at least consider aiming for the 10% offshore island area predator-free which New Zealand has today, so the unique species found on those islands can remain safe until we can eradicate introduced predators from larger islands, or perhaps even fly them to Mars.
Incidentally, the PFNZ trust is running a competition at the moment to update the above map of predator management in New Zealand.