THE BIRDS OF AUSTRALIA. 
it. One instance in particular, which came under my notice during 1909, 
is perhaps worthy of mention. About the end of April I several times saw 
a pair of Whistling Eagles standing on the side of a nest which had been 
built the previous season; this sort of thing continued until towards the 
end of August. In the meantime, a pair of Ravens built their nest in 
the same tree, from which I took five eggs on August 17th. Shortly 
after this I was busy with the shearing for a few weeks, after which, 
while riding past the tree, I saw two young Whistling Eagles sitting upon 
the Ravens’ nest, and the old Eagles’ nest was not used at aU during that 
season. I find that the birds on the whole vary as much in their habits 
as they do in their plumage at various ages. They are extremely erratic 
in the time they commence breeding, although, strictly speaking, they 
practically breed the whole year, but still they have what might be called 
their proper nesting season. During 1907 I took the first set of eggs on 
July 10th, 1908 Aprd 13th, 1909 May 18th, and 1910 March 5th. Their 
breeding appears to be governed by the amount of food there is for them; 
for instance, during 1907 all the rabbit destruction here was done with phos- 
phorus, and most of the rabbits died in their burrows, and the Eagles could not 
get them, so food was scarce, and I only took four sets of their eggs during 
the whole year. During 1908 we had a very serious drought, and heavy 
losses in stock all through the winter, consequently there was plenty of 
food for the Eagles, and I took thirty-two sets of their eggs. During 1909 
I used strychnine to poison the rabbits, and spring traps for the first time ; 
again there was a plentiful supply of food, and I took thirty sets of their 
eggs. In 1910 I again used strychnine and spring traps, and being a 
cool summer I commenced rabbit destruction at the beginning of the year. 
The result was this species commenced nesting earlier than I have ever 
Imown before and I took thirty-five sets of their eggs. . . . Their food 
consists principally of rabbits (in these parts), and yet I have never seen 
them kiU one themselves, and I very much doubt if they ever do so, 
excepting they might occasionally take a very young one. Many of their 
old nests have the remains of rabbits in them. The food, which I think 
they prefer to all others is the ground ‘Iguana’ or Lace Lizard (Varanus 
varius). I have several times seen about half-a-dozen making a meal off 
one of these reptiles, but I very much doubt if they killed it themselves.” 
Mi\ Savidge observed : “ It preys upon larger birds, poultry included, and 
small mammals ; about the swampy lands Coots and Redbills, etc.; are its 
principal food.” Dr. Macgillivray added: “This bird, when the Darling River 
is in flood, and the muddy water forces the fish to swim near the surface, 
has frequently been noticed to swoop down and pick them up with its 
