by Frankie Seymour
Predation seems to us a terrible thing. But, in a way, it is nature’s great kindness. It saves weak, sick or starving animals (and the excess young which all animals and plants are fated to produce on a planet where perils are many), from a painful, lingering death.
Only human predation is unequivocally cruel because it creates, for no other purpose than to kill and eat them, animals that would otherwise not exist. These domesticated species which no longer contribute any useful services to the ecosystem, contribute to the peril now faced by all life on the planet through their contribution to rising greenhouse gases and impact on other animals’ habitat.
Yet, despite this monopoly humans hold on predation, how often have we heard cats and foxes accused of preying cruelly on Australia’s small native marsupials and birds?
If you go looking for the science behind these accusations, you soon find that there is no evidence that cats have had any significant impact on native animal populations in mainland Australia. There is some evidence that cats may have had an impact on offshore islands, but this does not mean much because offshore islands are notorious for changing the entire composition of their ecosystems every century or so.
There is evidence that foxes might have added to the pressures that have destroyed so many native marsupials – but those marsupials could not have survived anyway. Once most of the native vegetation was cleared, the marsupial populations did not have the numbers and the resilience to survive. It is likely that foxes just delivered the final coup de grace to a number of already doomed individual creatures.
Keeping mice and rabbits under control
There is, on the other hand, ample evidence that cats and foxes have been critical in keeping rabbit, rat and mouse populations under control (except when the rat or rabbit food supply booms; predator populations always lag behind prey populations during these events). There is also evidence that many native predators have become almost wholly dependent for their diet on introduced prey animals, such as rabbits.
Despite this evidence, there have been virtually no comprehensive studies undertaken into the ecological services provided by naturalised species in Australia, and the consequences of eradicating these species (if we could). We have no idea how removing so much vegetation, so many prey animals and so many predators impact our remaining native species and ecosystems.
Moreover, we now have to accept that foxes, cats, rabbits, and so on, are part of the Australian ecosystem, for good or ill. No-one nowadays is silly enough to believe we can eradicate them. For each animal we kill, we just empty a niche for another animal of the same fast-breeding species to move into, and those new individuals are likely to be younger, stronger and more fertile than the ones we have killed.
Not much evidence except that 1080 is a cruel killer
So, firstly, we have the lack of evidence that most of the naturalised animals which are so often condemned as “feral pests”, “noxious species”, or “vermin”, are, in their own right, having any significant impact on Australian ecosystems.
Secondly, we have virtually no studies at all into the services now being provided to our ecosystems by naturalised species.
Thirdly, there is the very likely futility of killing animals and opening up niches for others of the same species.
Fourthly we have the simple ethical issue of whether it is okay to kill one innocent individual sentient being in order to protect another.
Finally, we have the extreme cruelty of the poisonous measures currently used to kill these animals.
It is time to stop trying to solve a problem with violence against defenceless animals. By all means, we should do all we can to assist nature to develop its own equilibrium. But not until we have a trace of a clue of what we are doing, and not with cruelty under any circumstances.
Tragically, some species might become extinct in the process. That will be our fault for past land use practices, not the fault of the species we introduced that have out-competed some natives or preyed on them. By interfering now, are we only make matters worse?
At least we can take some comfort from knowing that our naturalised foxes and cats will prevent the cruel, lingering deaths of some individuals of those vanishing species.