Did you know…
Koalas are renowned for being selective, if not fussy eaters. In any given area of koala habitat they will only eat a handful of the eucalypt species available to them.
In Australia there are over 900 species of eucalypt trees. Of these, koalas only eat 50-60 varieties. And, of these, in any local area, koalas only eat 10-12 species of eucalypt.
In the Port Macquarie/Hastings region of NSW, favoured food trees include Swamp Mahogany, Tallowwood and Forest Red Gum.
Staff and volunteers at the Port Macquarie Koala Hospital know that the quality as well as the quantity of the right species of leaves is highly important to the patients recovering from illness and injury.
Koalas typically eat 500 grams of pure leaf (not the branches) each day. However, if you factor in the browsing and selecting of specific leaves which is typical of koala behaviour, five times more leaf per koala per day may be required.
Koalas may at times eat bark, stems and the buds of trees and they eat a number of non-eucalypt species such as Casuarina, bottle brush and paperbark.
Volunteers at the Koala Hospital have observed koalas feeding and the process they go through. They sniff and check before they start eating a branch of leaves. They sniff at leaves to check the toxicity and many koalas learn individual toxic smells through trial and error. Leaf toxicity changes throughout the year depending on climatic conditions and season.
Leaf selection is likely to be driven initially by the mother’s home range, but as a juvenile moves away to other locations, it is driven by soil moisture, soil quality and the gut micro biome of the koala itself.