154 ANATIDA 
American Goosander, though it does not rank as a distinct 
species, shows in the adult male a well-marked black band 
across the wing-patch (Saunders). 
RED-BREASTED MERGANSER. JMergus serrator (Linneus). 
Coloured Figures.—Gould, ‘Birds of Great Britain,’ vol. v, pl. 
35; Dresser, ‘ Birds of Europe,’ vol. vi, pl. 453; Lilford, 
‘Coloured Figures,’ vol. vii, pl. 59; Booth, ‘Rough Notes,’ 
voli; pls: 16, los 17. 
The Red-breasted Merganser is the most abundant of 
the British Saw-billed Ducks. In many parts of Scotland 
and Ireland it is resident, breeding on islands or shores of 
inland lakes, and, to a less extent, in the vicinity of tidal 
estuaries ; in England it occurs only as a migrant. There is 
a considerable increase in numbers during autumn and 
winter, due to the arrival of migrants travelling southward. 
In spring, a return movement takes place, flocks continuing 
to press northward until late in May. 
In winter, the Red-breasted Merganser is rarely met 
with away from the tide: estuaries of large rivers, sheltered 
bays, and salt-water channels, are its favourite resorts. 
Assembling in large flocks, Mergansers may be seen 
swimming and diving in company with Wigeon and other 
common sea-fowl. Shy and vigilant by nature, they can 
rarely be approached within eunshot. 
During the spring-season (usually about the middle 6f 
April, when the birds are pairing) I have observed from a 
boat, with the aid of a binocular, some fifty Mergansers 
engaged in sport about the mouth of the river Liffey, 
Dublin. Of a sudden, with necks stretched and lowered, 
and head-plumes fully erected, two or three adult males 
dash across the water, hotly pursuing the females; the 
latter dive to evade their suitors, and reappear on the sur- 
face behind the rest of the flock. Espied a second time 
by the ardent drakes, the chase is renewed, until a few 
of the females, too closely followed, take wing, alighting 
several hundred yards away. 
In the water this bird swims low, little of its body 
being visible. On land it progresses in an awkward 
shuffling manner, assuming a semi-upright gait. Now and 
again [ have met Mergansers standing on a sand-bank at 
