AMERICAN EIDER 



307 



ary, July, November and December, from widely separated points along 

 the coast from Rhode Island, Massachusetts, Maine, and Nova Scotia 

 northward to Labrador and Hudson Bay gave the following approxi- 

 mate percentages: molluscs (including the blue mussel, 67), 82; crusta- 

 ceans, 7; echinoderms (including sea urchins, 4.5), 5; insects, 2; total ani- 

 mal food, 96 per cent. The 4 

 per cent vegetable food con- 

 sisted of drift and undeter- 

 mined material. Had more 

 of the stomachs come from 

 summer months it is likely 

 that the percentage of plant 

 food would have been in- 

 creased because in the stom- 

 achs of the July birds the 

 plant food furnished 12 per 

 cent of the diet; the crow- 

 berry, 2.44 per cent, repre- 

 sented the largest single item 

 of plant food. Gravel repre- 

 sented about 14 per cent of 

 the total stomach contents. 

 The eider is an undesirable 

 table bird as its flesh is of a 

 high, fishy flavour. 



The U. S. Biological 

 Survey (now the Fish and 

 Wildlife Service) conducted 

 a number of investigations to 

 determine the relationship of 

 American Eiders to the shellfish industries and has concluded that only 

 under exceptional circumstances do they cause any noticeable damage. 

 Shellfishes of commercial value, mostly scallops, are occasionally taken 

 but obviously are not sought out in preference to the common blue mus- 

 sel that is so abundant along the North Atlantic coast, and that has no 

 commercial value. The size and quantity of mussels consumed by these 

 birds is surprising. Remains of 185 shells an incredible number were 

 found in a single gullet and gizzard, and another well-filled gullet and 

 gizzard contained larger shells, 36 whole mussels, and fragments of 22 

 others. The gullet of another bird contained 11 entire mussels ranging 

 from 11/3 by 5/ s inches to 1 9/16 by .% inches; and the stomach or gizzard 

 of the same bird, 6 entire mussels from 7/ by i/ 2 inch to iy 2 by fy 

 inches and remains of 7 more. Occasionally the tongue of a bird is 

 caught between the valves of an open mussel, which usually results in 

 the bird's death; the mussel tightly clamps the tongue, causing strangu- 

 lation or starvation. Millais (1913) recounts that he once saw an eider 

 duck flying "with something like a thick stick projecting 5 or 6 inches 

 from its mouth, which it was unable to close. I snot the bird, an old 



