Here where I live, there were once about 70 species of birds, some of them just regular visitors. Then in the early 90s, major bush fires changed the ecology. This resulted in most resident species being replaced by a single territorial species (bell miner).
The miners drive away insect eating species, so that numbers of sap eating insects increase dramatically, trees, already under stress, die. I have watched this happen here, it's heartbreaking. A lot of animals, possums, sugar gliders, wallaby, birds, lizards and frogs, are predated by feral mammals. Now, it's all changing again, the bell miners are gone and we are overrun with Rainbow Lorikeets. I think Nature engineers change, but we ...

Here where I live, there were once about 70 species of birds, some of them just regular visitors. Then in the early 90s, major bush fires changed the ecology. This resulted in most resident species being replaced by a single territorial species (bell miner).
The miners drive away insect eating species, so that numbers of sap eating insects increase dramatically, trees, already under stress, die. I have watched this happen here, it's heartbreaking. A lot of animals, possums, sugar gliders, wallaby, birds, lizards and frogs, are predated by feral mammals. Now, it's all changing again, the bell miners are gone and we are overrun with Rainbow Lorikeets. I think Nature engineers change, but we have upset the nature and rate of the changes. I used to see the odd sparrow here, but not for many years now. Frogs still deafening at night outside. I have begun uploading photos to http://mynetimages.com/album/vk2yoc/
all of them taken here where I live. Lot's more as I get time. This is one Aussie backyard that really does have Kangeroos.