This section is from the book "The Balance Of Nature And Modern Conditions Of Cultivation", by George Abbey. Also available from Amazon: The Balance Of Nature And Modern Conditions Of Cultivation.
The ducks proper are distinguished from the swans by having shorter necks; and from the geese by having shorter necks, and legs less strong and placed further back. They also subsist largely on insects and other animal food, while geese and swans live mostly on vegetable food.
Fig. 149. - The Indian Runner Duck.
The Mallard or Common Wild Duck (A. boschas) is the original stock of the domesticated duck, which appears to have been reclaimed at a very early period, and is now sometimes utilized for effecting a cross between the domestic duck in order to produce a smaller, more fleshy and less fat bird for table, the male domestic duck, usually Rouen, consorting with the female wild duck, and after once crossing, the progeny are as much at home on the farm-pond as the tame birds.
Ducks of various small breeds, such as the black (East India) and Indian Runner, both excellent foragers, are often kept on ornamental waters, and render good service in keeping down weeds and confervaceous growths in the water, and in scouring the adjoining ground and freeing it from slugs and allied pests. This applies to all the species and varieties of duck kept mainly for ornament in moderate number on ponds and lakes. Too many ducks in proportion to the area of water and forage ground spoil both, the water being made muddy and foul, and the grass also in the immediate vicinity unsightly and unpleasant.. The apportionment of the drakes to the ducks deserves attention. On a quarter-acre of cemented pond one drake and two ducks proved disastrous to the latter. The drakes, therefore, as a rule, ought not to be reserved in greater proportion than one to every five ducks. The ducks must be fed every morning with small maize, buckwheat, etc., strewing major part in shallow water.
Domestic Ducks, Aylesbury, Rouen, etc., are always praised by poultry-keepers for shovelling up slugs, and they advocate admission of ducklings into gardens and vegetable grounds. This is a very questionable utility procedure where the crops are young and likely to be trodden down and broken, and in the case of ducklings over a month old, almost certain to do more harm than good. On the other hand, where the crops are advanced in growth and not likely to be injured by webbed feet under heavy bodies, ducklings of under a month old, or even older are useful for destroying slugs in gardens and vegetable grounds. The ducklings should be turned into the plot infested with slugs early in the morning or during moist weather, always on an empty stomach, and the ducks cleared off the ground as soon as they have done foraging. The question of the usefulness or otherwise of ducklings to cultivators of crops thus resolves itself into a matter for discriminative judgment.