10 

Fig. 9. Typical nest of Aleutian Canada goose during early incubation; note young leaves of Elymus arenarius. The height of this 
and other plants would have been considerably greater at hatching. 
its leaves and sheaths, which was dumped to the ground 
during frequent high winds, an undesirable situation at a 
nest. Spring beauty formed dense, slippery mats which may 
have made travel difficult for geese. 
Physiographic Selection for Nest Sites 
Slope. — Of a wide range of physiographic types available 
(Fig. 10), sea slopes were selected most frequently as nest 
sites. Essentially all vegetated sea slopes had nesting geese, 
and the concentration of nests on the south side of the island 
(Fig. 11) reflected the relatively large area of sea slopes 
there. 
Birds nesting on slopes steeper than 40° had significantly 
(P < 0.05) higher hatching success than those nesting on 
more gentle slopes (Table 4). Although hatching success 
seemed to be lowest on slopes of 11-20°, differences in suc- 
cess between pairs using the lower four slope categories 


VOLCAKIC 
PEAK 
—— North 

BEACH 
ALLUVIAL 
VALLEY 
Fig. 10, Cross section of Buldir Island, Alaska, showing physio- 
graphic types, 
(Table 4) were not significant. Nevertheless, the lowest 
nesting success was also recorded for birds using 11-20° 
slopes. 
Steep slopes were probably selected because they afforded 
good visibility. Only on these steep slopes would geese be 
able to view approaching predators over tall vegetation 
