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FAMILY — ANATIDAE. DUCKS, GEESE, AND SWANS 
General Description. As this is the only family included under the order Anseres the 
descriptive matter under the previous heading applies here and need not be repeated. 
The family is divided into five subfamilies: the Merginae or Mergan- 
sers; Anatinae or River Ducks; Fuligulinae or Sea Ducks; Anserinae or 
Geese; and the Cygninae or Swans. For the characteristics of these see 
under proper headings following. 
Subfamily — Merginae. Mergansers. Fish-Ducks. Saw-bills 
General Description. Fish-eating Ducks with a more cylindrical, tapering, and less 
spatulate or flattened bill than the other Ducks (Figures 113, 114). The cutting edges 
of the mandibles have a series of serrations giving rise to the popular name “Saw- 
bill.” The nail on the tip of the bill forms 
a small but evident hook. The hind toe 
(Figure 112) is developed into a flat paddle 
or fin-shaped lobe similar to that of the Sea 
Ducks and quite different from the hind 
toe of the River Ducks. The males are 
brightly and strikingly coloured, mostly 
in black and white. The females are 
dull coloured, with reddish heads and 
necks. Most plumages have crests. In 
the females and most young birds, the 
crests, to the casual eve, are ragged, and ioot of Merganser; 
without well-defined shape. scale, i- 
Distinctions. The saw-toothed bill easily distinguishes the Mergansers from the Sea 
Ducks which resemble them in the character of the hind toe. 
Field Marks. Typical Mergansers are long, slender Ducks with long, slim bills. The 
slenderness of general build and the long-headedness are apparent both at rest and in 
flight. When flying the bill, head, neck, and body are carried in a straight line which gives 
a drawn-out appearance that is quite characteristic. Mergansers, except the Hooded 
which is rather solitary, usually fly in long, single files or lengthened flocks approximating 
lines, rarely in irregular indiscriminate bunches as do other Ducks. They are seldom seen 
high in the air, but usually pass over the water low down and just above the surface. Scot- 
ers also have this habit, but are heavier in build and much blacker. 
Nesting. Mergansers in the breeding season are mostly river haunters nesting either 
on the ground, among rocks, or in hollow trees. 
Distribution. A small family; most of its species inhabit the northern hemisphere. 
Mergansers feed upon fish and shell-fish captured under water by 
diving; for this method of feeding their hooked and serrated bills are 
admirably adapted. They are, during the breeding season, mostly fresh- 
water frequenters, though they visit the sea sometimes in large numbers. 
They are not very desirable as food, though some young autumn birds, 
properly cooked, are not to be altogether despised. 
Economic Status. Mergansers eat fish and, in certain waters — such as 
at the heads of salmon streams — they may do appreciable harm. Ordinary 
trout streams are too small for these species and it is only in special 
circumstances that their depredations are serious. In waters that success- 
fully withstand commercial fishing, the fish taken by even a considerable 
number of Mergansers may be disregarded. In streams where angling is 
the most important interest too many Mergansers may be a just cause of 
complaint. However, Mergansers, like other birds, tend to take the food 
most easily obtained. The fish most highly valued by sportsmen are those 
agile, game ones that are seldom pursued by Mergansers or other feathered 
fish-eaters when less active ones are available. These birds should not be 
