42 THE SCOTTISH NATURALIST 



the country. This line takes a marked turn to the S.E. on 

 reaching the northern confines of the Forth, the birds passing 

 over the low-lying lands on either side of that river, and re- 

 appearing again as a breeding species on the moorland lochs 

 of Selkirkshire and Roxburghshire ; (2) After the colonisa- 

 tion of the central districts, various offshoots from the main 

 advance took place to east and west ; (3) Various districts in 

 Scotland, apparently perfectly suitable to the breeding habits 

 of the species, have not yet been colonised, and it would be 

 well if a careful lookout were kept for its appearance in these 

 localities ; (4) The steady and determined advance and 

 settlement of the Wigeon, this contrasting markedly with 

 the unstable and sporadic breeding habits of the Gadwall 

 in Scotland. 



It would appear that the arrival of the Wigeon as a 

 breeding species in this country took place as an extension 

 from its northern nesting grounds. The primary cause is 

 not altogether clear. It may have been overcrowding in its 

 principal breeding grounds in northern Europe, or it may 

 have been that abnormal weather conditions there induced 

 the birds to breed to the south of their northern nesting 

 quarters. Be that as it may, the Wigeon speedily became 

 established as a breeding species, and may now be con- 

 sidered one of our commonest nesting Ducks. No doubt the 

 beneficent influence of the Bird Protection Acts has done 

 much to produce this satisfactory result. 



