500 THE PIGEONS 



forms are found in the Azores, Madeira, and North-western Africa. In the British 

 Isles it is a well-known resident in practically the whole of Great Britain and Ireland, 

 except in treeless districts, but it has bred occasionally in small numbers even on 

 the Outer Hebrides and the Orkneys. Birds from Northern Europe are migratory, 

 and have their winter quarters in our islands and in Central and Southern Europe 

 as well as North Africa, but the migration limits of this species appear to extend no 

 farther than its most southerly breeding range. [F. c. B. J.] 



3. Migration. A resident, and a winter visitor in greatly varying numbers. 

 There is no evidence of any movement on the part of our resident birds, but they 

 may possibly migrate to some extent within our area, seeing that such movements 

 might well be indistinguishable from the subsequent wanderings of Continental 

 immigrants. The immigration referred to takes place on the east coast of Great 

 Britain, the Shetland Isles being visited by some of the migrants. The extent of 

 the immigration varies greatly from year to year, but at its maximum it affects the 

 greater part of our area, the species' numbers in Ireland, for instance, then receiving 

 large additions. As a rule, the birds first arrive in the British Isles late in October 

 or early in November, and their numbers are increased during the latter month ; 

 by the end of January a decrease may already have set in, and the majority leave 

 in February (cf. C. B. Ticehurst, British Birds, ii. p. 72 ; and others). What has 

 been said of the immigrants in Ireland is true of our area as a whole, namely, that 

 they " vary as to the localities they visit, the time they remain, and the seasons 

 in which they occur, being doubtless influenced by the rigour of the weather in 

 the countries whence they come, and also by the abundance of beechmast and other 

 food here " (Ussher and Warren, B. of Ireland, 1900, p. 222). Seasons in which 

 great immigrations have occurred are 1881, 1884 (especially : cf. British Associa- 

 tion Migration Reports, vi. p. 59), 1889, 1894, 1899, 1901 (cf. Nelson, B. of Yorks., 

 1907, p. 488), and 1907 (cf. C. B. Ticehurst, loc. cit.). A markedly gregarious 

 bird on migration and in the winter months generally : in seasons such as those 

 just named enormous flocks occur. [A. L. T.] 



4. Nest and Eggs. When built by the birds themselves, the nest is placed 

 in tall hedges or trees of all kinds at varying heights, but generally at a fair distance 

 above the ground, and is a flimsy erection of twigs, through which the eggs can 

 often be seen. (PL xxxvm.) But many nests are made upon old squirrel dreys or 

 nests of other birds, and it is not uncommon to find it breeding in ivy, on trees, 

 walls, or cliffs. It has also been known to build exceptionally on or quite close to the 

 ground, in heather or bracken, under boughs, etc. (cf. H. F. Witherby, Zoologist, 



