WHISTLING EAGLE. 
Mr. Tom TregeUas sent me a specimen, writing with it: “The specimen 
I am sending was shot at Yan Yean, the reservoir from which the water 
supply of Melbourne is drawn. The birds are fairly common in boggy or 
swampy country, where they may be seen hovering by the hour on the 
look-out for anything in the eating line. Although they are common, it is 
not at all common to be enabled to get a shot at one, as they are very 
wary and seem to be ever on the look-out for a possible enemy. At 
Swan Island I saw a good many of them, and at Westernport also they 
were fairly numerous, in fact too numerous, as there was always one who 
saw me sneaking on another and warned him.” 
North, in the Amt. Mm. Spec. Cat., no 1, Vol. III., 1911, pp. 227-236, 
has given a lot of interesting and valuable notes concerning habits 
and nidifications. Eegarding the former I extract the following. Firstly 
he records : “ It is, however, of rare occurrence near the city and quite 
different from Gould’s time. . . . The note is a loud whistling cry, 
resembling ‘ chu chu chu chu chu,’ rapidly repeated several times, and 
when once heard can be easily distinguished from that of any other of the 
Australian Accipitres. Although uttered during the day, it may frequently 
be heard just about dusk, and again occasionally through the night.” Mr. 
T. P. Austin’s notes are novel and worthy of reproduction: “Just before 
Haliastur sphenurm begins nesting in its normal breeding-season, it will often 
congregate in very large flocks, more often near water, a shallow swamp 
being a favourite place. I once counted flfty-two birds flying practically 
in a flock, just soaring round and round over a few acres. Upon another 
occasion I saw twenty of these birds fly from a Red Gum tree growing by 
itself on the edge of a swamp, and there were many others flying about. 
Sometimes these assemblies wiU be kept up off and on for two or three 
weeks, and their loud whistling cries may be heard the whole day long. 
After these congregations are broken up (which is not always done suddenly) 
a great many of the birds are seen in pairs; this is the time I notice they 
whistle most. A pair of birds having decided upon a nesting tree, and 
not having commenced building, will whistle at irregular intervals through- 
out the day. I find they vary very considerably in the time they take 
to build their nests ; in the majority of cases where they build a new 
nest, they take as near as I can judge about a month from the commence- 
ment until the first egg is laid ; but when a pair of birds occupy a 
previous season’s nest, they at times take much longer to build it up 
again. Why this is I have not been able to discover j unless it is that 
they take possession of the nest they used the year previous, long before 
they have any intention of laying, simply to prevent other birds from using 
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