^°'- ^'l Campbell, Insectivorous Birds. I I 



1905 J ' . . ■* * 



sizes of the birds, it must be remembered, point to the preponderance 

 of large over small insects, or small over large. This aspect is 

 most noticeable in this section. The Orioles are perhaps the only 

 birds exceeding n inches in length, with a few Wattle-Birds in the 

 forests and FriarT^irds along river frontages, that feed in the 

 tree-tops, and, as they are not by any means as plentiful as the 

 small fry, it is evident that there are not many large insects in 

 those positions to be followed up. 



As illustrating another point, it should be noticed that such 

 large birds as the Jackass, the Boobook, and small Hawks have 

 been seen feeding upon the great bunches of chafer beetles which 

 are often, in sumnier, suspended from the tree- tops. But section 3 

 proper is intended to represent mainly those small birds which, 

 with inquisitive persistence, pry among the wind-tossed tree- 

 tops. 



4. Birds specially useful to forest trees bring into notice 

 a subject almost untouched in this young country — forestry. All 

 must have been struck with the alarming number of native 

 timber-destroyers that exist. Whole genera of beetles and moths 

 quite common in Australia are timber-borers, and without the 

 natural help of certain of the bird inhabitants a forest would 

 soon be sadly decimated. The Black Cockatoos rank as the 

 most powerful operators by removing the offending insects in the 

 branches. These Cockatoos also feed largely upon hard native 

 fruits. 



But more serviceable would be those birds that picked off the 

 borers' eggs or the young insects before they have entered deeply 

 into the wood, and so deal with timber-destroyers at an early 

 stage. The birds specially fitted for this work are the Tree-creepers 

 (allied to the W^ooclpeckers of the old world) and the Tree-runners. 

 The former ascend the tree with a sidelong movement, prying 

 into the bark and crevices, bringing forth insects with their long 

 curved bills, and even creeping into larger holes and hollows in 

 search of food. On flying to another tree they invariably begin 

 near the bottom and ascend again the trunk and branches. To 

 the Tree-runners, a smaller genus of birds, is left mostly the care 

 of the upper part of the tree, into which the Tree-creepers do not 

 often go, and on the smaller branches they search up and down 

 for offenders. 



The Black and Grey Magpies may be placed next in importance, 

 for with their powerful bills they strip away the outer layers of 

 bark, reaching parts that the smaller birds cannot deal with. 

 Then there are several other birds — the Podargus (erroneously 

 called the Mopoke) and the Nightjars — which attack the insects 

 at quite a different time — during the perfect or winged stage — and 

 as most of the moths and beetle-borers are nocturnal these birds 

 are also nocturnal. In their important work of keeping down the 

 flying and egg-laying insects in the forest they are doubtless assisted 

 by the small species of Owls, as well as bats. 



Lastly must be mentioned the Lorikeets. Though feeding 



