Náttúrufræðingurinn - 2001, Page 11

■ SUMMARY
F/rstrecord offlounder, Platichthys
FLESUS (LlNNAEUS, 1758)ATICELAND
In late summer and autumn of 1999 a number of
flatfish was caught in brackish and fresh water in
the river Ölfusá and its tributaries near the
southwest coast of Iceland. One specimen of
this flatfish was sent to the Marine Research
Institute in Reykjavík and identified there as
flounder (Fig. 1). Although it is common in
coastal waters of Western Europe (Fig. 2), there
are no previous records of this species from
Iceland. In addition to the single specimen from
1999 the authors have investigated a total of 5
specimens caught in 2000 and 6 specimens
caught in 2001. Six of these specimens were
caught in brackish or fresh water, 5 in the river
Ölfusá area and one near Hornafjörður,
southeast Iceland (Fig. 3). Six specimens have
been caught in marine water, one at 27 m depth
in Lónsvík, southeast Iceland, and 5 at 11 m
depth in Herdísarvík, about 15 nautical miles
west off the outlet of river Ölfusá. Furthermore,
the authors have news of a flatfish caught in a
lake, Miðhúsavatn, on Snæfellsnes in 1999, the
specimen was not preserved but was pre-
sumably a flounder.
The 12 flounder investigated were 17-40 cm
long (total length) and weighed 72-848 g
ungutted (Table 1). The eight specimens aged
were found to be 2-6 years old, 5 of them
belonging to the 1997 year class. AIl three males
and all but the smallest female were found to be
sexually mature and specimens caught in late
March and early April 2001 were close to
spawning. The number of fin-rays in dorsal,
anal, and pectoral fins was within previously
published ranges for flounder, except for one
specimen with 47 rays in anal fin (published
range is 36—46). The number of vertebrae was
also within previously published ranges.
Food remains in stomach and intestines of
flounder caught in brackish and fresh water were
found to be amphipods (Gammarus zaddachi)
and gastropods (Lymnaea peregra). In speci-
mens caught in marine water only sand eels
(Ammodytes marinus) were found.
In view of known distribution of flounder, the
authors consider it most probable that the
specimens caught at Iceland have emigrated from
the waters of the Faroe Islands.
PÓST- OG NETFANG HÖFUNDA /
Authors 'addresses
Gunnar Jónsson
Hafrannsóknastofnuninni
Skúlagötu 4
IS-101 Reykjavík
gunnarj@hafro.is
Jónbjörn Pálsson
Hafrannsóknastofnuninni
Skúlagötu 4
IS-101 Reykjavík
jonbjom@hafro.is
Magnús Jóhannsson
V eiðimálastofnun
Austurvegi 3-5
IS-800 Selfoss
magnus.johannsson@veidimal.is
Fft/rmál/
Sumarið 2001 veiddu starfsmenn Suðurlandsdeildar Veiðimálastofnunar
á Selfossi fjórar flundrur í Ölfusárósi. Þessar flundrur veiddust frá 18.
júní til 26. júlí, tvœr í net og tvær í gildru. Ein slapp úr veiðarfæri en hinar
þrjár voru merktar með slöngumerkjum (ÍS 72132, ÍS 72162 og ÍS
72210). Verður fróðlegt að sjá hvort þœr endurveiðast og þá hvar. -Höf.
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