(Mew) Gull is a very common and numerous spring migrant at
Skogsøy, indeed it may be THE most numerous. The
is almost completely absent in the winter at Skogsøy so it
easy to pick up on the start of the spring migration in mid March.
Numbers build up until approximately mid April before slowly dropping
off again and by early May few are still migrating. Peak counts can
number several thousand, although 2000 is more regular.
Norwegian Ringing Atlas states that good population data are
missing for this species. Norway has a special responsibility for
- the latest estiamtes is that there are in excess of 150 000 breeding
pairs in the country. There have been reports of large scale declines
from much of its breeding range, including from a number of areas in
Norway. The species is concentrated in Europe and has an unfavourable
is another species that occurs in much higher numbers than, for
example, at Utsira.
following diagram shows the maximum recorded in a given three day
period (green line, scale on right hand axis). In order to give an idea
of the frequency of observation observer effort is presented as the
blue line (number of visits) and the orange lines (number of days the
species was recorded). More comprehensive data is available on the
Skogsøy downloads page.
the largest numbers of this species are recorded in spring, Common Gull
is also a common autmn migrant at Skogsøy. Passage commences
towards the end of July and continues well into November. The majority
of Norwegian birds winter further south around the North Sea, with
large numbers reaching the U.K. Some go as far as the Bay of Biscay.
Common Gull are undergoing a decline and should therefore be monitored.
Counts of returning birds in the spring would seem an ideal way of
On the best migration days passage is very concentrated around dawn
with numbers tailing off rapidly during the first few hours of
daylight. It is not just adult birds that migrate north in the spring -
non-breeders also make the trip.
The record is 5000 in three hours
The best counts often occur during light winds and sunny weather -
these factors seem to be more important than the actual wind direction.
During sunny weather at this time of year it is very common to have a
wind with a strong northerly component.
and below: Migrating
Common Gulls, Skogsøy, April 2015
B.O., Mobakken, G. og Bryne, O. 2004 Fugler
V., Runde, O. & Tjørve, E. 2003 Norsk
Stavanger Museum, Stavanger