Fróðskaparrit - 01.07.2004, Blaðsíða 73

EITURKOPPAR (ARANEAE) í FØROYUM: EITT ENDURSKOÐAÐ YVIRLIT
OG EIN DAGFØRING AV ÚTBREIÐSLU INNANOYGGJA
71
incidents and annual fluctuations or trends
in changes, B. gracilis may be taken as an
example. This species was first recorded in
the Faroes in 1978 (one female on Borðoy;
Bengtson and Hauge, 1979) and in Iceland
in 1974 (Bengtson et al., 1976). Since then
the species has been found in a number of
localities and districts of Iceland (Agnars-
son, 1996; Bengtson and Hauge, unpubl.)
but not recovered in the Faroes. Was this a
single vagrant, a failure to colonize or a
subsequent extinction? Indeed, similar
questions may be asked with regard to sev-
eral other spiders on the Faroese list (e.g. C.
dilutus, E. errata, H. nubigena, P. egeria,
W. obtusa).
Acknowledgements
We wish to thank Jákup K. Bærentsen for
collecting the samples from around Sund
and Kunoy in 1984 and Jóhannis Danielsen
and Janus Hansen for sorting these samples
and Gertrud Ohlsson for sorting the other
samples. We are grateful to personnel of the
Royal Danish Navy stationed in Tórshavn
for providing helicopter support in carrying
out the fieldwork on Lítla Dímun. ln this
context we also wish to take the opportuni-
ty to apologize to the landowners of Lítla
Dímun (living in Sandvík) for the intrusion
on their island and any disturbance our vis-
its may have caused. Bo W. Svensson and
the staff at the Museum of Evolution in Up-
psala most kindly provided us with data on
Faroese spiders collected by Áke Holm and
Nikolaj Scharff provided information on
Faroese spiders in the Zoological Museum
of Copenhagen.
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