eat food another frog would of eaten, or kill native animals with poison? are these true?
"Although toads do compete with frogs for food, and do sometimes eat frogs, the number of frogs doesn’t go down when the toads arrive. There have been several studies now – some relying on just counting frogs, others using more complicated systems like electronic listening posts to record the male frog’s calls before and after toads arrive – and none of them show any decline in frogs due to toads." -
http://www.canetoadsinoz.com/debunkingcanetoadimpactmyths.html
Well according to that website very few native animals are actually affected by their poison. It is mainly large predators that are effected, such as large snakes, goannas and quolls (marsupial carnivores).
Native animals are also starting to evolve to adapt to the presence of cane toads "First, the snakes that lived with toads wouldn’t eat toads when we offered them to snakes in captivity, whereas when given the chance, about half of the snakes from toad-free areas readily grabbed a toad – and usually died as a result. Second, the toad-exposed snakes were more able to deal with the toads’ poison. Third, the snakes from toad areas had smaller heads compared to their body size – so they were not able to eat really big (and thus, more dangerous) toads." -
http://www.canetoadsinoz.com/evolutioncausedbycanetoads.html
Of course they are still affecting the biodiversity of Australian native wildlife and some sort of humane action needs to be taken, but it seems that native animals are adapting to cane toads much better than what most people would have you believe.