Except during the breeding season the Dipper is a solitary bird, and 

 even at that time the two birds are not often seen together. Each pair 

 seem to haunt a certain part of the stream, beyond which they do not stray. 



The song of the Dipper is rarely heard except in the spring ; at that 

 season, amid the rush of the waters, he sits on some boulder amid the spray 

 from the waterfall singing his short song. It is a low warbling strain with 

 a curious admixture of grating sounds, something like the letters ' zzzt,' 

 and is repeated at irregular intervals. The call-note is a double l zzzt-zzzt,' 

 uttered most frequently as the bird takes wing. 



The food of the Dipper consists of the larvae of insects, which at this 

 stage of their development are found in the beds of streams. Among the 

 moss-grown pebbles at the bottom of the stream it obtains caddis-worms, 

 small molluscs, and water-beetles, and from the marshy banks of the stream 

 worms, gnats, and minute insects of every kind are procured. The bird has 

 been accused of destroying large quantities of the ova of trout and salmon, 

 chiefly on account of the method it employs in procuring its food ; but beyond 

 an occasional small fish, the Dipper subsists entirely on larvae, which are 

 in themselves the greatest enemies to the ova. 



The Dipper is an early breeder, and eggs are often laid in March. The site 

 chosen for the nest is usually on some ledge of rock or among the gnarled roots 

 of some tree which overhangs the water. Only once have I heard of a nest 

 being placed in a tree, and that because there was no other suitable place 

 for it anywhere near. Though it is often placed in a most conspicuous 

 position, it is so artfully built that it often escapes detection. On first sight 

 it appears to be only a patch of moss growing on the side of the boulder on 

 which it is placed. It is a domed structure like the Wren's, but the entrance- 

 hole can only be seen from below, as the upper side of the entrance overhangs 

 a little. The dome is constructed entirely of the moss which grows around 

 in such profusion. Inside is an ordinary open nest, rather like a Blackbird's ; 

 this is built of dry grass, twigs, etc., and lined with dead leaves of birch and 

 beech beautifully laid one on another. The same nest is often used year after 

 year, undergoing a few repairs each spring. 



The eggs laid vary in number from four to five, and are a pure and spotless 

 white, with a somewhat rough surface. They vary from ri to '93 inch in length, 

 and from 76 to '69 inch in breadth. Two broods are reared in the year. 



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