We estimated that 404,000, 436,000, 264,000, and 451,000
snow geese nested at Egg River in 1995 to 1998, respectively.
This is about twice as many geese nesting at Egg River than
in the 1980’s. Annual variation in number of nesting geese
was negatively related to spring arrival, which appeared to be an
important factor affecting the proportion of geese arriving
on Banks Island that attempt to breed each year.
Nesting success showed large variation among years, ranging from
71% and 65% in 1995 and 1997, to 93% and 88% in 1996 and 1998,
respectively. This is comparable to nesting success recorded for
snow geese at other large colonies. Both
1995 and 1997 were late years, which probably caused birds to
use considerable body reserves while waiting for snow to melt.
Late springs have strong effects on nesting performance of
snow geese at other colonies and appeared to be an important factor
affecting nesting success at Banks Island.
Clutch size was 3.5, 3.7, 3.7, and 3.8 eggs per clutch from 1995 to
1998, respectively. This is comparable to that recorded for snow
geese at other colonies of similar latitude. However, the relatively low clutch size in
1996, when birds could start to initiate nests immediately upon
arrival to the breeding grounds, suggests that birds may not have
been in optimal condition at the time of clutch formation.
We estimated that about 1-5% of the nesting population died at Egg
River in 1995 to 1998. There were likely several causes of death, but
avian cholera was confirmed in about half of the dead birds
examined in each year. Avian cholera was, thus, an important factor
affecting lesser snow geese nesting on Banks Island in all years.
Gosling survival during the first 2-3 weeks after hatch was 43%, 27%,
and 44% from 1996 to 1998, respectively. We suggest that weather
conditions and predation may have been important factors affecting
brood survival at Banks Island.
Use by geese had negative influence on availability of grass and sedge
in brood-rearing areas. We found indications that areas with high
use by geese were heavily grazed, even though we did not observe
evidence of permanent destruction to habitats.
Goose nest with part of dead fox as nesting material
This page was developed by
Gustaf Samelius who also took the pictures
