155 
BLACK DUCK.'' 
JljYJlS OBSCURJl. 
[Plate LXXIL— Fig. 5, Male.] 
Gmel. Syst. I, p, 541, No. 115. — Ind. Om. p. 871, Ab. 96. Dusky Duck^ Gen. Syn. Ill, p. 
545, 84, Arct. Zool. No. 496. — Peale’s Museum^ No. 2880 ; female^ 2889. 
THIS species, called by naturalists Dusky Duck, is generally 
known in Pennsylvania, and along the seacoast of New Jersey, and 
the neighboring country, by the name of the Black Duck, being 
the most common and most numerous of all those of its tribe 
that frequent the salt marshes. It is only partially migratory. 
Numbers of them remain during the summer, and breed in se- 
questered places in the marsh, or on the sea islands of the beach. 
The eggs are eight or ten in number, very nearly resembling those 
of the domestic duck. Vast numbers, however, regularly migrate 
farther north on the approach of spring. During their residence 
here in winter they frequent the marshes, and the various creeks 
and inlets with which those extensive flats are intersected. Their 
principal food consists of those minute snail-shells so abundant in 
the marshes. They occasionally visit the sandy beach in search 
of small bivalves, and on these occasions sometimes cover whole 
acres with their numbers. They roost at night in the shallow 
ponds, in the middle of the salt marsh, particularly on islands, 
where many are caught by the foxes. They arc extremely shy 
during the day j and on the most distant report of a musket, lise 
from every quarter of the marsh in prodigious numbers, dispersing 
in every direction. In calm weather they fly high, beyond the 
* Named in the plate Dusky Duck. 
