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FOOD HABITS OF SHOAL-WATER DUCKS. 1a 
FROGBIT FAMILY (HYDROCHARITACEABE), 5.75 PER CENT. 
The plants of the frogbit family eaten by the baldpate consisted of 
wild celery (Vallisneria spiralis), which was found in 12 stomachs, 
and waterweed (Philotria canadensis), in 1. Wild celery is a favorite 
food of the canvas-back, redhead, and other deep-water ducks, but 
as a rule it is not often found in the stomachs of ducks which do not 
dive. However, the stomachs of baldpates from several different 
‘localities were filled with wild celery leaves. This is very probably 
due to a peculiar habit which the baldpate has of following the 
diving ducks and feeding upon the leaves which they bring to the 
surface. This habit was noted by Wilson and Bonaparte® as early 
as 1831, and has been widely quoted by various writers since then. 
According to these early ornithologists, ‘‘The widgeon is the constant 
attendant of the celebrated canvass-back duck, so abundant in 
various parts of the Chesapeake Bay, by the aid of whose labour he 
has ingenuity enough to contrive to make a good subsistence. The 
widgeon is extremely fond of the tender roots of that particular 
species of aquatic plant on which the canvass-back feeds, and for 
which that duck is in the constant habit of diving. The widgeon, 
who never dives, watches the moment of the canvass-back’s rising, 
and, before he has his eyes well opened, snatches the delicious morsel 
from his mouth and makes off.” It is probable that these observa- 
tions are not entirely accurate, as the canvas-back is known to 
feed chiefly upon the rootstocks of the plant; the baldpate merely 
avails itself of the leaves thus cut off, brought to the surface, and 
‘discarded by the canvas-back. 
WATER MILFOILS (HALORAGIDACEAE), 3.48 PER CENT. 
Water milfoil ( Myriophyllum sp.) had been eaten by 24 of the 
baldpates, and bottle brush (Hippuris vulgaris) by 18. Many species 
of ducks feed upon the seeds of these plants in small numbers, but 
the baldpate so far as known is the only duck which shows any 
particular fondness for their foliage. Several stomachs were found 
to contain the seeds also, and in a very few instances they predomi- 
nated over the foliage, but the bulk of the food derived from this 
family of plants consisted of the tender leaves and stems. A series 
of baldpates from Klamath Falls, Oreg., especially, had partaken of 
the foliage of Myriophylium in considerable quantities. 
DUCKWEEDS (LEMNACEAE), 2.2 PER CENT. 
Like the gadwall, the baldpate shows less partiality toward the 
duckweeds than do some other ducks. The stomachs of three 
individuals, one each from Wisconsin, Utah, and Oregon, were 
6 Wilson, Alexander, and Charles Lucian Bonaparte, Amer. Ornith., III, p. 198, 1831. 
