Select three trees in the creek – any three trees – you choose. Have a very close look at each tree. Can you see the tree ‘hollows’? Tree hollows are holes in the tree. They may be in the trunk of the tree but usually they are at the end of a branch that has fallen off.
Can you count how many hollows each tree has? The larger a tree is, the older the tree is. Old trees usually have more hollows than smaller, younger trees. Is this what you have found as well?
Under each hollow entrance look down on the ground. Examine the ground closely. Is there any black things in the sand? They may be rather small and could look like black hundreds & thousands. This is bat droppings! Bats either like in caves or in trees in Central Australia. They don’t like it when its too hot or too cold, they like it just right!
Other animals that use tree hollows include a variety of birds (owls, ducks, cockatoos, etc), mammals (Brushtail Possum), frogs and reptiles. All these animals love tree hollows because its a nice constant temperature in the hollow and they don’t need to waste energy trying to keep warm or cool down. The hollows also keep them safe from predators (other animals what want to eat them).
See how many hollows there are in each tree. Can you spot them all? Can you see scratches around the entrance to the hollows – this is where animals have scratched the edge as they have entered. Cockatoos and parrots will also use their strong beaks to expand entrance to the hole.
Watch out for parrots and cockatoos making nests in the tree hollows. They’ll normally let you know if they are around. They screech their heads off as you approach!
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Big tree hollow
Found this tree hollow in my travels in Kashmir
Only old trees have hollows. Research has shown that jarrah, wandoo and salmon gum rarely form hollows before they are 120-150 years of age. A hollow large enough for a black cockatoo (which requires an entrance hole 25cm in diameter) will only be found in a tree that is even older than that.