Náttúrufræðingurinn - 2023, Blaðsíða 47

það greindist ein til viðbótar.31 Er það
sami fjöldi og er í gagnagrunninum
sem hér hefur verið notaður. Ef fjöldi
skráninga heldur áfram með sömu tíðni
það sem eftir er 21. öld verður fjöldi
steypireyða sem finnast dauðar talsvert
fleiri en á 20. öld. Er það í takt við fjölgun
í stofninum eins og talningar sýna.
Nú á tímum finnast steypireyðar allt
í kringum land en tegundin hefur verið
algengust undan Vesturlandi.71,80 Eftir
2001 breyttist útbreiðslan nokkuð og
fleiri dýr fóru að halda til undan Norð-
austurlandi.74 Rekhvalir, íshvalir og fleiri
dauðar steypireyðar hafa fundist mest
frá Vestfjörðum til Austfjarða, en einnig
nokkuð við Suðvesturland. Íshvalir hafa
einungis fundist við norðanvert landið,
frá Ísafjarðardjúpi austur í Loðmundar-
fjörð eða þar sem ís hefur helst orðið
landfastur við strendur landsins.
Þættir sem hafa valdið dauða steypi-
reyða hafa breyst frá því á 19. öld sem
og ástæður fyrir hvalaströndum. Nú
hafa engar veiðar verið stundaðar á
steypireyðum í rúm 60 ár og hvalveiði-
menn missa ekki lengur særðar
steypireyðar frá sér. Steypireyðastofn-
inn dróst mikið saman eftir að hvalveiðar
byrjuðu fyrir alvöru og virðist ekki hafa
náð fyrri hæðum og hvalaströnd færri á
20. og 21. öld. Á tímum heimstyrjaldar-
innar síðari kom fyrir að steypireyðar
festust í kafbátagirðingum en vænt-
anlega ekki lengur. Á hinn bóginn má
ætla að stórvirkari veiðarfæri og auk-
inn veiðifloti hafi skapað aukna hættu
fyrir hvali miðað við fyrrum. Þannig að
þótt veiðar á steypireyðum séu löngu
aflagðar, hafa nýjar ógnir komið í stað-
inn sem geta hægt á áhrifum friðunar.
ENGLISH SUMMARY
The whales at Ánastaðir in 1882,
other strandings and ice-locked
Blue Whales in Iceland
The present paper deals with four main
issues, three concerning Blue Whales and
one on recent methodologies for species
identification of marine mammals:
(1) Species determination of the
whales which became ice-locked at
farm Ánastaðir (N-Iceland) in 1882.
Samples were taken from their bones
(Fig. 2) and identified using mass spectr-
ometry. All turned out to be from Blue
Whales (Balaenoptera musculus) (Fig.
1). Further sampling is needed to ascer-
tain whether other whale species were
also part of the group of 32 that were
ice-locked and killed.
(2) Records of Blue Whales (in most
cases as identified by finders) were ex-
tracted from a database of 2082 records
(per February 2023) of whale strand-
ings and other whales found dead in
Iceland (direct hunting excluded). Most
of these records included stranded ani-
mals, but other mortality factors were
also involved, such as ice-locked ani-
mals, whales caught in fishing gear, and
animals found harpooned but had es-
caped (mainly during the period of in-
tense whaling by Norwegians in 1883 to
1915). In total 46 Blue Whales had been
entered in the database (2,2% of the to-
tal), from the period 1426 till 2011 (Tab.
1). Distribution of findings are from all
around Iceland, while majority is from
the northern parts of the country (Fig.
3). One of these whales was salvaged
and now is its skeleton on display at the
Whale Museum in Húsavík (Figs 4-5).
Many other whales in the database were
reported as baleen whales only (n=107).
Although precise species is unknown
many of these whales are believed to be
Blue Whales, as indicated by the Icelan-
dic names that have been used by find-
ers, while others could relate to two or
more species. Comparing numbers as
reflected in the database about twice as
many Blue Whales were recorded from
the 18th century as the 19th century. This
is believed to mirror the large popula-
tion decline from the late 18th century to
the 19th century due to whaling opera-
tions by Norwegians.
(3) A literature search was made
of whale remains found during exca-
vations of middens and ancient farm-
steads. Whale bones were reported in
72% of the 110 publications examined,
of which 66% were reported as uni-
dentified but only 6% identified to spe-
cies, some relating to the same findings.
Whale bones are notoriously difficult
to identify to species using morpho-
logical features, except perhaps skull
and teeth. Therefore, recent molecular
techniques will undoubtedly revolu-
tionize species identification of marine
mammals found during excavations in
the next years to come.
(4) Molecular methods for species
identification are rather recent, not the
least those using collagen and mito-
chondria. Not much has been written on
these methods in Icelandic. Therefore,
a detailed overview of these methods is
given in the text for Icelandic readers.
Whaling with harpoon has been car-
ried out for much of the period since
Iceland was settled by man shortly be-
fore year 1000. Legal codes regarding
stranded whales found with harpoon,
has been in force since the early law
books in the 12th century. Yet, the catch-
ing of Blue Whales did not take off until
in the late 18th century, or after the ex-
plosive harpoon had been invented by
the Norwegian Foyn. Many harpooned
whales escaped from the whalers were
later found stranded or afloat at sea.
A general agreement is among whale
researchers that the Blue Whale popul-
ation decreased drastically during the
Norwegian whaling period 1883-1915.
During that period the maximum of 327
animals were killed in a year, but about
6500 in all. A world ban on killing Blue
Whales has been in force since 1960.
Whaling is not the only reason why
greater numbers of dead whales were
recorded in the 18th century versus dur-
ing the 19th. Climate was particularly ad-
verse during the last decades of the 18th
century, with the coasts of the North and
East frequently becoming ice-locked,
with detrimental effects for various
whale species, such as Blue Whales.
Although Blue Whales (Figs 6-7) have
been protected in Iceland for over 60
years, the population increase has been
slow. Population size was estimated about
3000 animals in 2015, probably still well
below the numbers before industrial
whaling started before 1900. Although
mortality factors like hunting and ice con-
ditions are non-existent or less now, other
factors such as modern fishing effort,
large fleet and advanced gear could still
deflate population recovery.
135
Ritrýnd grein / Peer reviewed