WHITE WAGTAIL 9 



later stages (Blair and Tucker, 1941) , and it is safe to assume that this 

 is true also of the present race. The fledging period is 14-15 days. 



Plumages. — The plumages are fully described by H. F. Witherby 

 in the "Handbook of British Birds" ( 1938, vol. 1 ) . The nestling ( de- 

 scribed under the pied wagtail, M. a. yarreUii, and doubtless not differ- 

 ing in the present race) has smoke-gray down distributed on the inner 

 and outer supraorbital, occipital, humeral, ulnar, spinal, femoral, 

 crural, and ventral tracts, but very scanty on the last two. The mouth 

 is orange-yellow inside, with no spots, and externally the flanges are 

 very pale yellow. 



In the Juvenal plumage the upperparts are brownish gray, lores 

 and ear coverts dingy, huffish white, breast band dark, smoky brown, 

 rest of breast and flanks huffish gray, throat and belly dull white with 

 a yellowish tinge, wings and tail much as in adult. In the first winter 

 the male is like the adult female, except for having usually rather more 

 black on crown, and the female is also like the adult of that sex but 

 does not show any white on forehead or black on crown as the adult 

 may do. Tlie gray crown has also usually an olivaceous tinge. 



Food. — The food consists mainly of insects, principally Diptera, but 

 Jourdain (1938, vol. 1) mentions also Neuroptera, Trichoptera, 

 Ephemeroptera, etc., as well as small snails. 



Behavior. — Several of the chief features of behavior are mentioned 

 later under "Field marks." The incessant up-and-down tail motion 

 is one of the bird's most noticeable characteristics. Though largely 

 terrestrial, wagtails perch readily on buildings, fences, and so forth, 

 and somewhat less freely on trees. The mainly insect food is secured 

 chiefly on the ground or in shallow water or in little aerial excursions 

 after flies or gnats. The birds are much attached to the neighborhood 

 of water and may often be seen wading in the shallows of pond, lake, 

 or stream. This association is, however, by no means obligatory, and 

 they may be regularly met with far from water. Farmyards are a 

 popular resort, and the birds will follow the plow in the fields, search- 

 ing for small worms and burrowing larvae. In the high north they 

 have naturally less opportunity of benefiting by agriculture and cul- 

 tivation as an extra source of food supply. In Arctic Norway they are 

 mainly coastal birds and may often be seen, as indeed they may be in 

 the other parts of their range, foraging for flies and other arthropods 

 among the debris about high-water mark on the seashore. 



Voice. — The principal note, used both in flight and when settled, 

 but especially in flight, is a rather shrill tschizzih. There is also a 

 rather more musical tzi-wirrp (the m' to be pronounced as in chirrup) 

 with variants, and the alarm note of breeding birds is an incisive chick. 

 The song is a simple, but lively, warbling twitter, consisting largely 

 of slurred repetitions of call notes with variants and modulations. It 

 is delivered on the wing or from a perch or while the bird is running 



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