272 A PRACTICAL HANDBOOK OF BRITISH BIRDS. 



chiefly by night in fields, marshes and swamps, leaving security of 

 ponds, lakes or sea at dusk, to return at dawn. Gregarious in 

 winter. Call of male a low " quork," of female a loud " quark." 

 In spring male utters a soft " dreek, dreek." 



Breeding-habits. — Usually nests near water, often in sheltered de- 

 pression in ground, but also at times in pollarded willows, holes of 

 trees, nests of Crows and other birds, ivy- covered ruins, etc. Nest. — 

 Composed of down and feathers (see Brit. Birds, Vol. II, PI. 1) 

 mixed with leaves, grass, etc. Eggs. — Usually 7 or 8 to 13, 

 occasionally more. Colour variable : usually greyish-green or 

 greenish -buff, but occasionally pale blue. Average of 83 eggs, 

 57.8x41.0 mm. Max. : 62x42 and 60x43.2. Mn. : 50.5x39 mm. 

 Breeding -season. — Usually in March but exceptionally even in 

 February and thence onward to late in autumn. Incubation. — By 

 female alone. Period: 26th day (W. Evans.) Probably in a purely 

 wild state single-brooded. 



Food. — Mainly vegetable, including many species of aquatic and 

 land plants {Ranunculus pantothrix, Callitriche verna, Lemna, 

 Ceratophyllum submersum, Potamogeton, seeds of Galium, also 

 Persicaria, etc.) ; also algse, Zostera marina, acorns, blackberries, 

 grain of various kinds. Aquatic insects (Diptera, water -beetles., 

 larvae of caddis-flies, etc.) and small mollusca (Tellina balthica, 

 water-snails, etc.), leeches, worms, frogs and their spawn so that it 

 may be said to be almost omnivorous. 



Distribution. — British Isles. — Resident, passage -migrant (mid- 

 Sept .-end Nov. to end March-mid -May), and winter -visit or (mid- 

 Sept. -early Nov. to March). Generally distributed. 



Distribution. — Abroad. — Northern Hemisphere, in winter south 

 to north Africa, Madeira, Canaries and north India. Also in North 

 America, but at least the Greenland form is separable and possibly 

 the Iceland ; in winter (in America) south to Mexico, West Indies, 

 and Panama. 



ANAS STREPERA 



301. Anas strepera L. — THE GADWALL. 



Anas strepera Linnaeus, Syst. Nat., ed. x, i, p. 125 (1758 — Europe. 



Restricted typical locality : Sweden). 



Anas strepera Linnaeus, Yarrell, iv, p. 370 ; Saunders, p. 425. 



Description (Plate 6). — Adult male. Winter and summer. — Crown 

 and nape black-brown, feathers tipped and barred cinnamon ; 

 mantle and some scapulars vermiculated blackish -grey and cream, 

 in some feathers of lower-mantle olive -brown freckled cream, rest 

 of scapulars mouse-grey edged buff-brown, long ones mouse-grey ; 

 back black or olive -brown, usually finely freckled and vermiculated 

 cream ; rump and upper tail-coverts black glossed dark blue ; fore- 

 head, lores, cheeks, sides of neck, chin, throat and fore-neck light 

 buff or cream, spotted and barred dusky or black-brown ; feathers 



