Many healthy ecosystems include the dingo...

Many healthy ecosystems include an 'apex' or top-order predator. In Australia, a healthy relationship exists between dingoes and herbivores. Dingoes regulate native herbivores such as macropods and exotic herbivores such as rabbits, feral pigs and goats by removing sick or diseased animals and stabilising numbers. For example, kangaroos and emus tend to be less abundant where dingoes are common. Australian prey species, particularly macropods, have developed predator responses such as avoidance of dingo urine and, in a chase situation, are known to flee to water and to eject pouch young. Interestingly, mounting evidence suggests that many mammal extinctions across Australia could be traced to persecution of dingoes by humans. Top order predators have been recognised as keystone species in virtually all ecosystems. The loss of a top order predator can trigger a cascade of extinctions through a process known as mesopredator release.Essentially this means the number of medium-sized predators increase in the absence of larger predators. Scientists have discovered a negative relationship between dingo abundance and the number of cats and foxes in given areas. That is, wherever they co-occur, dingoes suppress the effects of introduced predators such as foxes and feral cats on native fauna. Species such as native rodents, bilbies, quolls and rufous hare-wallabies suffer local extinctions where no dingoes are present, since foxes and feral cats quickly populate the area. Thus, maintaining and, where possible, reintroducing populations of dingoes is an important strategy in conserving vulnerable native species.