Many reptiles rely on rocks and logs for shelter. You can help protect reptiles by buying quarried stone for rockeries rather than collecting bushrock. Hollow logs provide shelter not only from cold, rain and predators, but shelter animals from fire as well. It is important to remember that while hollow logs do, in fact, grow on trees, they usually take at least eighty years to develop. It is important to try to think in time frames of eighty years when managing vegetation.
Cats cause a great deal of damage to Australia's fauna.
Unfortunately, there is little difference between feral and domestic cats in this regard, except that feral cats are hunting to survive. If you own a cat, the responsible thing to do is to have it desexed and keep it indoors at night. Never dump cats or kittens in the bush. Take them to an animal shelter or have them humanely put down. Other introduced animals that feed on reptiles may have a serious long-term impact on populations.