( 100 ) 

 SOME NOTES ON DIVING DUCKS. 



BY 



CHARLES E. ALFORD, f.z.s. 



In all the wonderland of Ornithology there is, perhaps, no 

 study more fascinating than the habits of Diving Ducks. 

 The freedom and grace of their movements, the ease with 

 which they slip beneath the waves, to reappear, like little 

 sea-witches, apparently from nowhere, and the fact that we 

 as yet know so little of their movements when once they have 

 vanished into the depths, naturally fill one with a longing 

 to learn more about this strange side of their lives. 



Only recently several interesting notes on the periods of 

 dives have appeared in British Birds, and perhaps a few of 

 my own observations, conducted chiefly along the coast of 

 the North Pacific, and covering a period of many years, may 

 in their humble way throw yet another ray of light on this 

 interesting but obscure subject. 



As one of your contributors has already stated, accurate 

 observation is extremely difficult, and I should like to add, 

 intensely exhausting when sustained for any length of time, 

 for two reasons : the short interval between the dives, during 

 which one must record one's observations ; and the great 

 strain on the eyes from being fixed almost continuously upon 

 the water in order to watch for the duck's reappearance on 

 the surface. 



My observations have, in most cases, been conducted in 

 salt water, usually in a little bay that varies in depth from one 

 to five fathoms at high tide, and of which I know every yard 

 of the bottom. The species that have come under my notice 

 comprise the following : the Surf-Scoter {Oidemia perspicillata) , 

 the White-winged Scoter {Oi. deglandi), the Buffel-headed 

 Duck iBitcephala albeola), the Goldeneye {B. clangida), the 

 Scaup (Nyroca marila), the Harlequin-Duck {H. histrionicus), 

 and the Red-breasted Merganser {Mergus serraior). Of these, 

 the Buff el-head. Surf -Scoter, and Harlequin can only be 

 considered stragglers to the British shores, whilst Oi. deglandi 

 has never yet, I believe, favoured us with a visit. 



Regarding the question of depth of water and its relation 

 to the period of the dive, that has recently been raised in your 

 columns, it has been my experience that, whilst ten con- 

 secutive dives of one individual in a given depth may show 

 great regularity, those of another individual, in the same 



