38 



MIGRATION. 



Winter 

 visitors to 

 the southern 

 hemisphere. 



Double 

 breeding a 

 myth. 



Alleged 

 double 

 breeding 

 of Bam- 

 Swallows. 



Of Nord- 



mann's 

 Pratincole. 



and Asia, is an Arctic region, which is the breeding-ground of great numbers of migratory 

 birds. Many of these winter in our islands, whilst others are regular spring and autumn 

 visitors, passing along our coasts on migration, from their Arctic breeding-grounds to their 

 winter-quarters in Southern Europe or Africa. In the southern hemisphere there are no 

 Antarctic breeding-grounds, whence similar migrants could visit Natal. No part of South 

 Africa is cold enough to be a breeding-ground of Arctic birds, and the land at the Antarctic 

 pole is too cold for them. The natural consequence of this state of things is, that in South 

 Africa there are no migrants from the Antarctic Region, either in winter, or passing 

 through in spring and autumn to winter further north. To compensate for the absence of 

 such an important section of migratory birds, Natal and other parts of South Africa are 

 visited every year by an equally important section of migratory birds, a migration which 

 has no parallel in the northern hemisphere. 



The fact that in the Antarctic Region there is no land suitable for the breeding of 

 birds, except a few species of Penguin and Petrel, is the cause of the apparently anomalous 

 circiunstance that the northern hemisphere is only accidentally visited by migratory birds 

 whose breeding-grounds are in the southern hemisphere. South Africa is, however, visited 

 by numerous regular migrants from the northern hemisphere — birds who spend half the 

 year, from September to March, in the summer of the southern hemisphere surrounded by 

 other species, some of them congeneric, busily engaged in the duties of incubation, but they 

 themselves looking on with absolute indifference. In addition to the Plovers and Sandpipers, 

 and the Barn-Swallows which have already been mentioned, many other species, such as the 

 Swift (Gypselus opus), the Willow-Wren [Phylloscopus trocliilus), the Sedge-Warbler [Aero- 

 eephaliis phragmitis), the Great Sedge- Warbler {Acrocej)hcdus turdoides), which breed in 

 Northern Europe and North-western Asia, cross the tropics and enjoy a second summer in 

 the Transvaal, Natal, and other parts of South Africa. The fact that these birds, which 

 spend the summer in Europe, are found in South Africa during the South- African breeding- 

 season, has given rise to the legend that some birds • breed twice in the year — in June in 

 Europe, and in December in South Africa. It is very difficult to prove a negative, but 

 when the evidence of these alleged cases of double breeding is carefully examined, it always 

 proves to be unsatisfactory. Andersson, in his ' Birds of Damara-Land,' remarks of the 

 Barn-Swallow that it breeds in that country ; but there can be little doubt that the Swallow 

 which he mistook for the Barn-Swallow was the White-throated Swallow (Hirundo albigu- 

 laris), a species which he does not mention, and which he probably mistook for the female 

 of our bird. His further remark that, in consequence of the scarcity of houses, it breeds in 

 rocks and trees, adds still more doubt to the accuracy of his observations. I have seen the 

 Barn-Swallow breeding under overhanging cliffs in the Dobrudscha, but I never heard of 

 its having been found nesting in a tree. Nordmann's Pratincole (Glareola melanopfera) is 

 also stated, on the authority of Mrs. Barber, to breed in South Africa ; but as this bird and 

 the Wattled Starling {DilopJius caruncidatus) are both known in that country as the Small 



