Fróðskaparrit - 01.01.1992, Blaðsíða 49

THE EXOTIC LAND PLANARIAN . ..
53
senting all four sampling sites) gave an
average of 8 (maximum 11) juveniles per
capsule, the newly emerged planarians
being cream coloured and up to 10 mm in
length when elongated.
Discussion
An attempt has been made to gather infor-
mation which may elucidate possible
routes of migration for A. triangulata both
to and within the Faroe Islands, and factors
underlying the obvious success of the land
planarian in these North Atlantic islands.
It appears that A. triangulata has been
colonising the Faroes for at least a decade.
The first sighting, back in 1982, was when
specimens were noticed in the downpipes
of the local Parliament building in
Tórshavn, the roof of which is covered with
grass turf (Bloch, 1992). This roofing turf
comes from the outskirts of the city, and
was collected in 1978 from a site in an area
where army barracks for British soldiers
had been constructed during the Second
World War (T.G. Leivsson, pers.comm.).
The next probable sighting of the land pla-
narian, in 1987, was when poorly preserved
specimens originating from potato fields on
the outskirts of Tórshavn were brought to
the museum. After the dramatic find of
hundreds of specimens in the potato field at
Kvívík in 1990, and the broadcasting of the
matter in 1991, the public has become well
acquainted with the exotic New Zealand
flatworm and this has resulted in a steady
flow of reports from gardens, churchyards,
potato fields, etc. on several of the islands
(Bloch, pers.comm.).
In New Zealand, A. triangulata is usual-
ly found under objects lying undisturbed on
the soil surface for some time, and often in
association with woodlice, slugs and cen-
tipedes (Fyfe, 1937). A similar pattem of
habitat selection and fauna association is
evident for the Faroe Islands.
Possible routes of passive migration
From discussions with the islanders it
becomes obvious that there are, and have
been, many possibilities for the import of
plant material (often with soil) and thereby
for the passive migration of the land pla-
narian to the Faroes, both directly from
New Zealand and indirectly via other
countries, especially Scotland.
Faroese fishermen have a long tra-
dition of retuming home with
goods from abroad, such as vegeta-
bles (e.g. potatoes) and other plant
material (e.g. omamental plants),
as well as livestock (e.g. sheep)
from the British Isles, in particular
the Scottish mainland.
For many years regular cargo ships
with loads from various countries,
particularly Denmark, Scotland
and Westem Norway, have trans-
ported goods to the Faroes. For
example, potted plants and seed
potatoes from Scotland and Den-
mark have been widely distributed
in the Faroes.
During the Second World War,
there was considerable non-con-