CORMORANTS 
57 
Though hitherto called “Common” Cormorant this is the rarest of 
our eastern Canadian cormorants. The species occurs on the European 
coast and was given the name “Common” because of its abundance about 
the British Isles. 
Economic Status. Owing to its rarity it is of little economic importance 
in Canada. 
120. Double-crested Cormorant, chow duck. i.e cormoran a aigrettes. 
Phalacrocorax auritus. L, 36. Plate II B. A large Cormorant. Adult: solid black, 
with greenish reflections. Feathers on back dull 
bronze with black edges, giving suggestion of over- 
lapping scales. Bare face and square-cut gular 
pouch, orange. Crest when present, double, one over 
each ear, of filamentous plumes. Juvenile: dark 
sooty brown, lightening below, the scaly appearance 
of back evident. 
Distinctions. This species in the east is likely 
to be confused with the preceding one only. In 
adult plumage the absence of any white at the base 
of the gular sac and on the flanks is diagnostic. In 
other plumages, size, the presence of twelve instead 
of fourteen feathers in the tail, and the whitening of 
the feathers adjacent to the gular pouch must be 
relied upon. Early in the spring the fihimentous 
crests on the sides of the head instead of a ragged ruff as in the previous species are charac- 
teristic; but these features are lost early in the season, before nesting begins, and hence 
are usually of little help in determination. 
Through the interior of the continent it is the only cormorant likely to be met with, 
but on the west coast it may need distinction from several species. Size similar to Brandt’s 
Cormorant, much larger than Pelagic. Black edgings to dull bronze black feathers evident 
in all plumages. Lower line of gular pouch cut square across throat not indented to heart- 
shape (Figure 95, compare with 96 and 97). No distinct lightening of plumage around 
gular pouch. 
Field Marks. Size, and yellow face and sides of bill should distinguish from Pelagic. 
Black or evenly coloured featheration about base of gular pouch, when seen, will separate 
it from Brandt's. 
Nesting. In bulky nests, among rocks on islands, cliffs, or other almost inaccessible 
localities. Occasionally in trees. r 
Distribution. Across the continent. Breeding in Canada at various points on the 
Atlantic coast, the Gulf of St. Lawrence, Lake Superior, and throughout the Prairie 
Provinces north to Great Slave Lake. Common on the Pacific coast, but almost absent 
from the interior of British Columbia. Nests at Cape Flattery, and Forrester Island, 
just across the border to the north, but known to breed within British Columbia only on 
Bare Island, off the south end of Vancouver Island. 
SUBSPECIES. The bird of the west coast is separable from that of the prairie 
interior and the east, the Eastern Double-crest (le Cormoran it aigrettes de l’Est ) Phala- 
crocorax auritus auritus, by somewhat larger size and the presence of considerable white 
in the crest, hence the name, White-crested Cormorant (le Cormoran a aigrettes blanches) 
Phalacrocorax auritus cincinalus. 
This is the common cormorant, or Crow Duck, of the east coast and 
of the prairies and large central lakes. It nests on bare islands or rocky 
cliffs, occasionally in trees, on or by large bodies of water, sometimes in 
immense communities, or in company with pelicans, gulls, or herons. In 
British Columbia it is confined to the coast, where it seems more or less 
of a migrant, or a winter visitor. Although it has been found nesting 
directly north and south of the Canadian coast we have only the single 
breeding record for British Columbia. Colonies should be looked for on 
the outer shore of Vancouver Island. 
Figure 95 
Double-crested Cormorant; 
scale, L 
