Náttúrufræðingurinn - 1976, Page 103

regular clrift migrants are, however, om-
ilted, although the study area lias yield-
ed more new and rare species in these
categories than any other part of Iceland.
For the purpose of tliis paper the
Öraefi area is taken to include a semi-
circular belt of mountains and an ad-
joining lowland fringe around the west,
south and east side of the Öraefajökull
ice-cap. The Öraefajökull (2119 m) is a
southern protrusion of the Vatnajökull
icefield (area about 8400 km2), one of
the largest glaciated areas in the world
after the Antarctic and Greenland. The
eastern and western limits of the study
area are marked by two big glacial rivers,
the Jökulsá on Breidamerkursandur and
the Skeidará on Skeidarársandur. These
two sandur areas are extensive fluvio-
glacial outwash plains, built up by braid-
ed, glacial streams.
The study area thus includes the entire
inhabited jrart of the civil parish Hofs-
hreppur and forms a narrow belt between
the Öraefajökull-Vatnajökull icefield and
the sea, broadening considerably to the
west.
The mountain belt forms the foothills
of the icefield. It is intersected by glaciers
and swiftly-flowing glacial rivers; sorne of
the glaciers reach the lowland fringe.
l’lant and animal life are most abundant
in the lowland region and in the lower
parts of the foothills. In the lowland
region fairly extensive bogs and marshes
are founcl at Hnappavellir and Fagur-
hólsntýri. A strip of boggy meadows,
which is intersected in three places by
glacial streams with adjoining íluvio-
glacial deposits of variable breadth, also
extends front Fagurhólsmýri to Svínafell.
Kvíármýri at Öldulón, just west of Kvíá,
is the third boggy part of the area. Fairly
extensive areas of birch shrub and birch
woods are found on the Skaftafell slopes
and on the west side of the sheltered
Morsárdalur at Skaftafell where Baejar-
stadaskógur is notable because of its tall
(up to 13 m) birch trees. Luxuriant brush-
woods of birch also cover the south-facing
slopes above the farm of Svínafell, a lim-
ited area just west of Sandfell and at the
easternmost farni of the area, Kvísker,
which forms an isolated oasis on the
Breidamerkúrsandur.
The coastline of the area consists of a
sand bar or a beach ridge a few metres
high and rarely over 500 m wide. Behind
the beach ridge there is usually a dis-
continuous line of shallow lagoons which
are rapidly being filled in by fluvio-
glacial deposits so that their northern
part constitutes an outwash plain varying
in width. The surf-ridden sand and
shingle shores are unsuitable for shore
birds as they are almost devoid of liíe.
The only exception is the isolated head-
land of Ingólfshöfdi (76 m) which rises
above the surrounding plain and forms
perpendicular marine cliffs on its east
and soulh sides. Ingólfshöfdi supporls
large numbers of breeding sea-birds.
The climate in the Öraefi area is rela-
tively mild and humid throughout the
year. At Fagurhólsmýri the mean annual
temperature is 5° C, the mean lor Janu-
ary is 0.0° and for July 10.7°. The mean
annual precipitation is 1761 mm. The
precipitation varies a great deal frorn one
place to another within the area. At Kví-
sker the mean annual precipitation has
exceeded 3000 mm (the highest l'igure for
one year being 3674 rnm). At Skaftafell
and Svínafell in the westernmost part of
the area the precipitation is mucli lower
than at Kvísker and Fagurhólsmýri.
The geographical features of the Öraefi
area are in many ways unique. Due to
these it lias until very recently been the
most isolated inhabitcd area in Iceland.
One of the niany interesting ornithologi-
cal features of the area is tliat tlie narrow
belt between the Vatnajökull-Öraefa-
jökull icefield and the sea acts as a
bottle-neck through which many migrants
have to pass in spring when arriving
from the southeast, i.e. mainly from the
British Isles. Consequently tlie area is
eminently suited for the study of visible
migration.
I am greatly indebted to Finnur Gud-
mundsson for reading an earlier version
of the manuscript and for many helpful
suggestions.
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