tundra from the Alaska Peninsula north 
through the Noatak and Selawik valleys; 
stratum 2 contains the spruce-muskeg 
habitat of the interior from the hmoko and 
Koyukuk River valleys east to the Cana¬ 
dian border. Stratum 3 designates the 
mountain valleys of southern Yukon and 
northwestern British Columbia. 
Data from previous years have been 
recalculated within the new strata so that 
figures are comparable for 1963 and 1964. 
Weather and habitat conditions 
The weather book for Alaska was com¬ 
pletely rewritten in May 1964. Phenolog- 
ically, conditions were at least a month 
late, from the southeastern coastal areas 
to the Bering Sea and Arctic coasts and 
throughout the interior. 
Waterfowl movements and behavior 
were directly, and adversely, affected by 
the following conditions: The spring thaw 
began in a routine manner in April. The 
winter's sparse snowfall in the low river 
valleys melted rapidly and created runoff 
ponds. Pintails, mallards, and white- 
fronted and Canada geese started to arrive 
on schedule in the Fairbanks area by 
April 20-22. By May 1 the temperatures 
had dropped, and soon all the open ponds 
froze. On the night of May 8, for ex¬ 
ample, the temperature dropped to -1° in 
contrast to 72° on the same date in 1963. 
Even the day-time temperature seldom 
reached much above freezing until the 
middle of the month. The Tanana River 
ice pool was won on May 20, the latest 
date in its long history. When the Tanana, 
the first of the major rivers to break, 
finally opened there was still over 6 feet 
of solid ice in the Black River above Fort 
Yukon. It was June 3 before the ice fi¬ 
nally cleared the river at Fort Yukon. 
Some of the larger lakes and most of the 
smaller permanent ponds had some open 
water around their edges by the first of 
June, but they all contained ice. All 
lakes, large enough, had ice solid enough 
to land on skis. The mouth of the Yukon 
River was still frozen on June 10. 
When the cold weather finally broke by 
the first of June, temperatures soared. 
The heavy snow pack in the mountains 
and near the coast melted rapidly, flood¬ 
ing many of the lower nesting grounds. 
On June 5, black brant and cackling 
goose nesting grounds were a solid sheet 
of water from snow melt. The Bering 
Sea coast was still frozen, which prevent¬ 
ed this water from running off through its 
normal channels. Large flocks of brant 
and geese, which would ordinarily be in¬ 
cubating by this date, were flying aim¬ 
lessly about the outer delta. There were 
many snow geese still passing north up 
the Bering Sea coast enroute to Siberia, 
exceptionally late for them. Very few 
whistling swans were nesting on the 
Yukon-Kuskokwim Delta by June 5. Nor¬ 
mally, most of them would already be 
well into incubation. 
With the severe temperatures of early 
May, most of the pintails and mallards 
which had arrived on schedule departed 
from the interior. Of those that re¬ 
mained, many became emaciated, and 
some mortality was reported. This 
physiological setback will undoubtedly 
have an adverse effect on the productivity 
of at least the early nesting species. 
Breeding population index 
There was no significant change in the 
total duck breeding population or in any 
of the numerically important species 
with the exception of mallards, which 
were down about 20 percent. There was 
a definite shifting of the population from 
the interior to the coastal habitat; the 
interior was down by 15 percent and the 
coastal was up by an equal percentage. 
Apparently, when the ducks pulled back 
from the early May freezeup they moved 
to the southern coast, and many followed 
the ice line up through Bristol Bay and 
the Yukon-Kuskokwim Delta without re¬ 
turning to the interior. The large per¬ 
centage fluctuation for several of the 
species counted in small numbers is not 
meaningful, for instance, green-winged 
teal and shoveler (tables B-l to B-3). 
Our system of expanding these small 
samples into an accurate total population 
is not adequate for the task. 
3 
