40 LONGEVITY RECORDS 



head, Old-squaw, Harlequins, six Eiders, and the three Scoters, all of 

 which are preponderantly animal feeders; molluscs, crustaceans and in- 

 sects form the bulk of their food. Of all the Diving Ducks, the Old- 

 squaw is the one which partakes most of fish; even so fish form only 

 about 10 per cent of its diet. 



MERGANSERS are fish-eating ducks, and obtain their food by 

 pursuing the smaller members of the finny tribe beneath the surface of 

 the water. 



ALL DUCKS, GEESE, AND SWANS require a certain amount of 

 gravel which aids the gizzard in grinding the food consumed. This sub- 

 stance forms an important part by volume of the total stomach content, 

 and varies in amount from 5 to 50 per cent of the total bulk. 



The feeding habits of each of these birds, the food taken, and the 

 percentage that each item of food represents in the average diet, are 

 given in the Life Stories of the various forms. 



LONGEVITY RECORDS 



The following list of ages attained by individuals of the Ducks, 

 Geese, and Swans was compiled from various sources. As would seem 

 natural, the highest records are those of captive birds. Generally speak- 

 ing, it would appear that ripe old ages for birds of this family are: ducks 

 20 years, geese 30 years, swans 40 years. There seem to be no records, 

 however, of birds attaining these ages in the wild state, owing no doubt 

 to the attention they receive from the gunner, to depredations from 

 numerous natural predators, and to the fact that banding records do not 

 extend over a sufficiently lengthy period. 



In a letter to the author, dated January, 1941, Manley Miner says, 

 "It is not uncommon for a duck to carry a band 10 years before being 

 shot . . . Jack Miner has some Canvas-backs and some Swans on his 

 sanctuary that went over Niagara Falls in 1922 and were crippled and 

 sent to him. He gave them first aid treatment and today they are well 

 and active on the sanctuary. How old these birds were when they went 

 over the Falls no one knows, but all we know is we have had them in our 

 possession 19 years." 



Of the ages attained by Mute Swans, Dresser (1880) says that a 

 common age seems to be about 30 years. It is said that these birds have 

 been known to live from 50 to 100 years. 



AGE RECORDS (in years). Whistling Swan, 8, 9, 19. Trum- 

 peter Swan, 12, 32i/. Canada Goose, 6, 8, 9, 15, 25, 29, 33. White-front- 

 ed Goose, 6, 111^. Blue Goose, 5, lQi/ 2 . Common Mallard, 7, 9, 10, 11, 

 l2i/ 2 , 14, 15, 15i/, 20. Black Duck, 7, 10. Gadwall, $i/ 2 , 6i/ 2 , 1\/^ 16. 

 European Widgeon, 4i/ 2 , 20. European Pochard reared a brood an- 

 nually for 20 years. Baldpate, 6i/ 2 , 7i/, 8 1/3, Si/ 2 , 9 1/3. American Pin- 

 tail, 10, 11, 12, 12i4, 17. Green-winged Teal, 7, 8. Blue-winged Teal, 4. 

 Cinnamon Teal, 4i/ 2 . Shoveller, 4i/ 2 , 5i/ 2 . Wood Duck 4i/ 2 , 5, 7i/ 2 , 8. 

 Redhead, 10, 11, 12, 14, \6i/ 2 . Ring-necked Duck, 10. Canvas-back, 

 Wi/ 2 , 19. Greater Scaup, 5i/, 6i/ 2 , 7, 8, 10, lli/ 2 . Lesser Scaup, 10. 

 American Eider, 5. 



