Náttúrufræðingurinn - 2008, Side 34

Náttúrufræðingurinn
svipfar hefur verið talið mikilvæg
orsök breytinga á fyrstu stigum eftir
einangrun stofna.10
SUMMARY
Small benthic charr can be found all over
Iceland, including the highlands. Fish
were caught from five populations near
Jökulsá á Fjöllum; from Herðubreiðar-
lindir, Grafarlönd, Jökulsárgljúfur, Prest-
hólar and Klappará. These populations
were found in three areas; the highlands
(Herðubreiðarlindir and Grafarlönd),
lowlands, connected to the ocean (Prest-
hólar and Klappará) and in-between
0ökulsárgljúfur). The morphology of the
fish was different among populations.
The fish from the high-altiude areas
were similar in morphology, and the fish
from the low-altitude area were also
similar in morphology. However, the
stomach content of the fish did not
reflect the difference in the morphology.
There were some differences in the rela-
tionship between length and age among
the populations. The fish from the high-
altitude areas were larger than those
from the low-altitude areas when at 4
years of age and older, which indicates a
slower growth within the low-altitude
populations. Even though the popula-
tions appear to be similar, they are differ-
ent in morphology when examined in
details. It is possible that these observed
differences can be related to environ-
mental factors, although there are no
clear relations to diet. The great number
of Small benthic charr populations in
Iceland offers a unique opportunity to
study the importance of ecological fac-
tors in the evolution of fish.
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Um höfundana
Hrönn Egilsdóttir (f. 1983) lauk BS-prófi í líffræði, á braut
fiskifræði og skyldra greina, frá Háskóla íslands vorið
2007 og stundar nú meistaranám í sjávarlíffræði við
háskólann í Plymouth, Englandi.
Bjarni K. Kristjánsson (f. 1971) lauk BS-prófi í líffræði
frá Háskóla íslands árið 1994. Að prófi loknu stund-
aði hann rannsóknir á hrognkelsaseiðum undir leið-
sögn Agnars Ingólfssonar prófessors og lauk fjórða-
ársverkefni frá Háskóla íslands 1997. Hann hefur
starfað við Hólaskóla frá 1998 við rannsóknir á eðli
og uppmna fjölbreytileika innan tegunda íslenskra
ferskvatnsfiska. Bjarni lauk meistaranámi 2001 og
stundar nú doktorsnám við háskólann í Guelph í
Kanada og Hólaskóla.
PÓST' OG NETFÖNG HÖFUNDA/AUTHORS' ADDRESSES
Hrönn Egilsdóttir
Kársnesbraut 127
IS-200 Kópavogur
hronne@gmail.com
Bjarni K. Kristjánsson
Fiskeldis- og fiskalíffræðideild Hólaskóla
Háeyri 1
IS-550 Sauðárkrókur
bjakk@holar.is
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