138 ANATID^E' 



it from other Ducks, while its habits of diving exclude the 

 possibility of its being mistaken at a distance for any of the 

 Wild Geese. 



Food. Eider Ducks are constantly plunging under 

 water ; they descend to a great depth and remain beneath 

 the surface for a considerable time, snatching mussels (their 

 staple diet) from off the rocks. They also eat crabs, cray- 

 fish, and a small quantity of seaweed. 



The flesh, rank and fishy, is eaten by the Greenlanders. 



Voice. The voice is low and murmuring, resembling the 

 syllable curr, softly produced ; as a rule, the bird keeps 

 silent unless alarmed. 



Flight. The Eider Duck can travel at a consider- 

 able speed on the wing, still the flight is heavy and not 

 buoyant. 



Nest. Though this bird builds on the ground, its nest 

 may be found on cliffs, hundreds of feet above the sea-level. 

 But the more usual site selected is a low, flat-topped island, 

 fairly clad with marine vegetation, in clumps of which the 

 nest may be placed. Sometimes a crevice between rocks or 

 loose stones is utilised. The materials are dry grass and 

 seaweed, to these, which form the foundation, bits of 

 heather, stems, and campion, are sometimes added. The 

 nest is thickly lined with grey down, the well-known Eider- 

 down of commerce ; as incubation proceeds the mother-bird 

 continues to add more down to the nest. 1 



Incubation begins about the end of May and lasts for 

 twenty-eight days. During all that time it seems evident 

 that the hatching-bird abstains from food, a fact which 

 has been vouched for by observations made on birds in 

 captivity (Payne-Gallwey, ' Letters to Young Shooters,' Third 

 Series, p. 173). 



The eggs, five to eight in number, are usually of a light 

 olive colour, but the shade varies even in the same clutch. 



The sitting-bird is often remarkably tame (especially in 

 countries where the Eider Duck is protected by law), and 



1 It may be mentioned that the down which is so characteristic a 

 feature of the lining of Ducks' nests, is plucked by the mother-bird from 

 her own breast. The down of aquatic birds is remarkably light and soft, 

 and retains among the interstices of its fibres, the heat given out from 

 any body with which it is in contact. The softness, lightness, and 

 elasticity of Eider-down, with its wonderful heat-retaining properties, 

 renders it a highly-prized material for coverlets. 



