COMMON SHELDRAKE 217 



animals: univalve and bivalve mollusks, insects, small crustaceans and worms. 

 Occasionally a small fish or some fish-spawn is taken. At times it visits pastures, 

 where it feeds on worms and slugs rather than on grass (Seebohm, 1885), but it does 

 at times feed upon vegetable matter, presumably more so during the breeding 

 season. Naumann, whose observations were made chiefly on Sylt during the sum- 

 mer months, speaks of vegetable matter as comprising "a large part" of its diet. 

 This includes the tender parts and seeds of various maritime plants, and in the 

 spring, on the Friesian Islands, at least, the newly sown grain, particularly barley. 

 The sea food is rarely obtained in deep water, nor is the bird often seen tipping up, 

 but is usually found wading in shallow water, or poking through seaweed on the 

 shore, or fishing in puddles left on the mud-flats. Here it obtains chiefly small 

 shrimplike animals of the genera Crangon, Palaemon, Gammarus and seaworms 

 (Arenicola lumbricoides) . During moult and rearing of the young, reedy districts 

 are occasionally resorted to, where small frogs and even fish become the objects of 

 prey. As many as twenty thousand small shells have been found in the stomach 

 and crop of one individual, shot in Belfast Bay, Ireland, in February. Most of 

 these were Mya purpurea, Skenea depressa and Paludina muriatica. To give an idea 

 of the size of these animals, it might be added that the Skenea is about as large as a 

 clover seed, and the Mya is somewhat larger. This is the same food on which the 

 gray mullet attains a great size (W. Thompson, 1851). The following species of shell- 

 fish have also at various times been found in the stomachs of Sheldrakes: blunt 

 bubble-shells (Cyclichna obtusa), small cockles (Cardium edule), porcelain tellina 

 {Tellina tenuis) and the laver spire (Rissoa ulvce) (Gladstone, 1910). The young in 

 down are said to feed almost exclusively on sand-hoppers (Dixon, 1893). 



Old birds have been seen stamping and paddling on the mud to bring up cockles, and 

 tame birds in a poultry -yard were seen doing the same thing while waiting for their 

 food (Cordeaux, 1896). 



Courtship and Nesting. Sheldrakes pair in February or March, perhaps in 

 this respect not differing from the true ducks, some of which pair even in January. 

 They are rather late breeders, nesting in April and May in the regions about the 

 North Sea; in May in south Russia (Radde, 1854); and as late as the first week in 

 July in north Finland (von Heuglin, 1871a). In Europe the species is a maritime 

 breeder except for isolated occurrences (see London Field, July 2, 1921), but in the 

 Caucasus and in Asia it is an inland breeder, frequenting the saline marshes and 

 lakes. The birds pair when they are two years old, at which time they assume full 

 plumage. MacPherson (1892) cites the case of a one-year-old male, who refused 

 to breed though confined with an amatory female, but voluntarily mounted guard 

 over some flappers of its own kind. Mr. Hugh Wormald also finds that they never 

 breed in his ponds the first year. The couples are exceedingly attached to each 



