Fróðskaparrit - 01.01.2009, Blaðsíða 101

(EITT ÁR VÓRÐU REIÐURSTAÐIR HJÁ HAVHESTI (FULMARUS CLACIALIS) f FØROYUM
EYGLEIDDIR VIÐ VAKMYNDATÓLI
99
Nest-site Year Exodus Length (days) Days with one-bird-visits Longest run of days without visit Breeding remarks
1 2006 27 Apr - 21 May (24) 7 8 21 May1
2007 4 May - 26 May (22) 12 3 no breeding
2 2006 21 Apr - 21 May (30) 7 9 21 May1
2007 29 Apr - 24 May (25) 5 13 24 May1
3 2006 28 Apr- 21 May (23) 5 9 21 May1
2007 2 May - 28 May (26) 25 1 28 May2
6 2006 30 Apr - 21 May (21) 1 20 21 May1
11 2006 21 Apr - 23 May (32) 8 10 24 May2
2007 29 Apr - 20 May (21) 6 10 20 May2
12 2006 30 Apr - 26 May (26) 7 10 no breeding
15 2006 30 Apr - 21 May (21) 4 10 21 May2
1 Incubating (exact date of egg-laying uncertain)
2 Egg laid
Table 7. Observations of pre-laying exodus at video surveilled nest-sites of Northern Fulmar in the Faroe Islands.
Date and length of exodus is defined by the longest run of days without visits by two individuals (assumedly a pair)
on the same day.
detail for 7 nest-sites in 2006 and 2007. Since
the exodus may be sex-biased the length of
it is here defined as the continuous run of
days without the presence of the pair (i.e.
two individuals) at the nest-site being recor-
ded. In the two years exodus started be-
tween 21 April and 4 May and lasted until
20-28 May and varied in length from 21 to
32 days (Table 7). However, the longest se-
quence of days when no fulmar was recor-
ded at the nest-site ranged between 1 and
20 days, but for most of the sites the period
of absence was in the order of 8-10 days.
Likewise, the number of days during the ex-
odus when the nest-sites were visited by one
individual varied considerably between the
sites (1-25 days). In three cases the length of
exodus could be related to sex since the fe-
males were ringed but not the males. Hence,
at site no. 1 in 2007, the male regularly vis-
ited the nest-site during the female's exodus
and maximum length of his absence was
three days, whereas at sites no. 3 and 6 in
2006, the males were absent during a period
of 9 and 19 -20 days, respectively; in the lat-
ter case at the same time as his partner.
Discussion
Fisher (1952), in his seminal work on the
species, recognized and described in some
detail the general patterns of annual cycle
and colony attendance in the Northern Ful-
mar. Basically, across the species’ breeding
range, time schedule of breeding events is
similar (also considering high Arctic colo-
nies); besides, adult fulmars intermittently
visit, or regularly occupy the breeding sites
for much of the year, being absent from the
colony only during a period in autumn and
an exodus prior to egg-laying (see Mallory
and Forbes (2007) and references therein).
This extensive annual attendance at the