20. Found originally in Southeast Asia, which invasive insect has established a super colony that has totally transformed the flora and fauna of Christmas Island?
From Quiz Everything UnAustralian
Answer:
Crazy Ant
Land crabs are vitally important to the forest ecology of Christmas Island as, while digging their burrows, they turn over the soil, and fertilise it with their droppings but the super colony of crazy ants have killed huge numbers of many species, to the extent that robber crabs, red crabs, and blue crabs have been completely wiped out in areas of high crazy ant populations.
This has meant that, in turn, seedlings which would have been eaten by these crabs are flourishing, changing the whole structure of the forests. It is estimated that up to 20 million crabs have been killed by this super colony and, worryingly, the ants have also been found in Queensland and the Northern Territory.