Barnacle Geese on Kolguev Island 61
©Wildfowl & Wetlands Trust
Wildfowl
(2013) 63: 56–71
nests in 2011 and 2012. Overall, however,
these newly-colonised areas would not have
added >10% to the area of covered by the
delta colony.
By 2006, the Barnacle Goose nesting
distribution was no longer restricted to the
coastal zone. Transects undertaken in
central Kolguev found at least 23 “inland”
colonies, most associated with Peregrine
Falcon nesting territories and one with a
Gyr Falcon
Falco rusticolus
nest (Fig. 1). Not
all colonies were monitored every year, but
those inspected during two or more seasons
show that colony size varied across years
(Kruskal-Wallis test:
H
4
= 22.2,
P
< 0.001),
with a general tendency for the colony size
to be greater in more recent years (2011–
2012) than at the start of the study (2007–
2008) (Mann-Whitney U test:
W
= 611.5,
n
1 = 32,
n
2 = 21,
P
< 0.001, Table 2).
Nesting success also varied, with the mean
proportion of clutches hatched per colony
ranging from 59% (s.d. = 34%,
n
= 5
colonies) in 2007 to 92% (s.d. = 8.6%,
n
= 3
colonies) in 2006 (Table 2), but the
substantial variation in hatching success
between colonies within years (particularly
in 2007) meant that the difference between
years was not significant (Kruskal-Wallis
test:
H
4
= 4.15, n.s.).
In 2006–2008, Barnacle Geese were
mainly associated with Peregrine Falcons
that nested on steep slopes in the upper
reaches of the Peschanka River and its
major tributaries; they were seldom found
around falcon pairs nesting in the watershed
hills. Thus, in 2007–2008 only two out of
five Peregrine Falcon nests in the hills of
central Kolguev Island were known to have
Barnacle Goose colonies around them
(territories F_17 and F_18 in Table 2),
compared with 13 out of 14 Peregrine
Falcon nests along the river systems with
associating Barnacle Geese in these years.
The other three colonies in the hills (F_12,
F_14 and F_15) had 5–25 nests of White-
fronted Geese and Bean Geese associating,
with minimal distances of 3–5 m and a
maximum of up to 100 m between the
falcon and goose nests, irrespective of
Table 1
. Number of geese recorded in the Peschanka River delta colony, in relation to
the whole of the Russian-breeding Barnacle Goose population.
Year Population Colony size
% of Russian Data source for colony size
size
1
(no. of
population
individuals)
1989 100,000
1,600
1.6
Gavrilo 1991
1995 250,000
10,000
4.0
Morozov & Syroechkovsky 2004
2001 300,000
50,000
16.0
Anufriev 2005
2006 500,000
90,000
18.0
Anisimov 2007
1
Total population size from Fox
et al
. 2010.
