BIRDS OF SHETLAND 



fication of birds which is by no means easy of 

 solution. The hooded or grey crow at first sight 

 appears obviously to be of a species distinct from 

 the black carrion crow. In the first place, its 

 plumage is parti-coloured — grey and black — 

 and differs essentially from the total blackness of 

 the carrion crow known in England. Again, 

 the grey crow visits England on migration in 

 winter only, whereas the black, when not resident, 

 is a summer immigrant, and is known as a regular 

 breeding species in this country. Furthermore, the 

 habits of the two birds are in many ways dissimilar, 

 the black crow being distinctly a tree-loving bird, 

 whilst the grey is rather a frequenter of moors 

 and waste places, especially of the low hills by the 

 sea, and even of the shore itself. Yet to set 

 against this, we have the curious fact that the 

 two birds mate freely together, and that in the 

 same nest young of both the black and grey 

 forms are found. On these grounds, and by reason 

 of their structural identity, the Editor of Yarrell 

 concludes that no specific distinction can be main- 

 tained. 



Perhaps the most striking species to be regularly 

 found in the innumerable lochs of Shetland are 

 the divers.. This small group, consisting of 

 three species, the great northern and the black 

 and red-throated, are well and aptly named. 

 Divers they are essentially, every line of their 

 graceful yet powerful forms being drawn with a 

 view to swift progression beneath the water. 



The great northern diver, with the jet-black 

 plumage of his back and wings barred with regular 

 lines of pure white, is a conspicuously handsome 

 bird, the black-throat being only slightly less 

 striking. Each of the three species frequents 

 the sea — ^the great northern and the red-throat 

 occurring on the English coasts in winter — but 



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