l86 NEW YORK STATE MUSEUM 



and has a bill marbled with dusky and yellowish, while the Black duck 

 has a plain olive-green or yellowish green bill. 



Length 20-25 inches; extent 32-38; wing 10. 5-12; tail 3.5-4.5; tarsus 

 1. 5-1. 8: bill 2-2.4; weight 2.7-3.5 pounds. 



Distribution. The Black duck is the commonest of all our river ducks 

 and is fairly abundant both on Long Island and in the marshes of western 

 New York during migration season. It breeds in suitable localities, when 

 left undisturbed, in all parts of the State, but is much more common as a 

 summer resident in the northern counties. On the coast of Long Island 

 it is abundant throughout the winter and is common on the central lakes 

 as long as they remain open. On Canandaigua lake even when frozen over 

 for its entire length this duck remains, often in large flocks, sitting on the 

 ice in the middle of the lake and feeding in the open shallows of the outlet at 

 night. The Black duck is commonest, however, from the time the marshes 

 are open till the last of April, when the greater number have passed to their 

 breeding grounds. They return in force in October and are common until 

 late in November when the last which are to pass farther southward have 

 departed. It is an exceedingly wary bird and soon learns to give decoys 

 and "blinds," or "hides," a wide berth, and when disturbed on its feeding 

 grounds will remain all day on the open lake or ocean and return to feed 

 only when darkness has settled. Like the Mallard, the drake of this 

 species has a low reedy quack, while the duck's note is a loud resonant 

 quack, quack, quack. When frightened she will shout quack slowly and 

 sharply many times in succession. 



Like the Mallard the Black, or Dusky duck, feeds on wild rice, buck- 

 wheat, weed seeds and nearly all manner of vegetable substances, also 

 devouring snails, frogs and other aquatic animals with a gluttonous greed, 

 especially in the springtime. On the morning of October 26, 1901, I shot 

 a Black duck from a flock of 75 birds, which were returning to Canandaigua 

 lake from a flooded cornfleld. From its gullet and gizzard I took 23,704 

 weed seeds, which together with a few pebbles, snail shells and chaff were 

 the sole contents of its stomach. Of these seeds 13,240 were pigweeds 

 (Chenopodium and Amaranthus), 7264 were knot grass (Polygonum), 

 2624 were ragweed (Ambrosia), and 576 were dock (Rumex). 



