Food consumption of the American merganser. (Fisheries research report: 1661)

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have been some growth in weight, which would be expected at this time
of year, but not enough to necessitate a correction in estimating food
consumed by the merganser, in view of the precision of the experiment.
Food Consumption
Merganser II was released on Section 4 Lake at 1:00 PM,
April 30, 1962. Before release on the lake, her left wing was
pinioned. She weighed 2 pounds, 3 ounces at this time. Captivity
had not tamed her.
At the conclusion of the experiment two attempts were made
to capture her alive. On the night of May 14, an effort to locate her
was made. It was hoped that she would remain immobile in a beam of
light and could be easily caught in a long-handled dip net. We could
not find her. The second attempt was made during the day of May 17.
We harassed her continually until she tired but we could not catch her
in a dip net. Finally in mid-afternoon she hid so well that three
of us could not locate her. On May 21, she was killed with a shotgun.
She weighed 2 pounds 4 ounces and had the remains of two trout,
judged to have been six or seven inches long in her stomach.
The difference between the two population estimates on
Section 4 Lake indicated a decrease in the population of 216 trout
(Table 4). Loss of seven of the trout can be explained; one was
caught by a fisherman, one, shorter than 7 inches, died after being
hooked deeply and released, two died from unknown causes, and three