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from old newspapers, old journals, photo archives and the
natural history museums in Denmark. To date, 67 sperm
whale strandings have been documented in Denmark since
1572.
As noted above, the first documented sperm whale
stranding in Denmark was in 1572. The last stranding
was in 2011. In the intervening time, sperm whales have
periodically stranded in Denmark. It is worth noting that no
sperm whales stranded in Denmark during the eighteenth
century, but 1996 and 1997 are years that stand out. In 1996
a total of 20 sperm whales stranded in Denmark. Sixteen of
these strandings occurred at the same time during a mass
stranding on Rømø. In 1997 another mass stranding took
place on Rømø, when 13 sperm whales stranded.
The sperm whale is the largest of the Odontocetes
(toothed whales) and is a deep diver found in almost all
deep (>1000 metres) ice-free waters of the globe. The shal-
low waters of the North Sea are not a natural habitat for the
sperm whale. The Shetland-Faeroe Channel is an important
migration route for sperm whales travelling between the
northeast Atlantic and the (sub-)Arctic. However, migrating
sperm whales sometimes enter the North Sea – also known
as a “sperm whale trap”. The sperm whales’ navigation
abilities are poor in shallow waters and they feed mainly
on deep sea squid, which are not found in the North Sea.
The whales will therefore be weakened if they do not reach
oceanic waters, and they may consequently strand along the
North Sea coasts. There has been much speculation as to
why sperm whales lose their way into the North Sea, but
there is no definitive answer. One explanation is that solar
activity produces geomagnetic disturbances which could
lead to navigational errors by migrating whales. Shifts in
the distribution of prey because of climatic changes may
also be an explanation, and human offshore activities and
pollution of the ocean may affect the sperm whales’ mi-
gration. A more speculative idea is that the population of
sperm whales is growing, and that it is therefore inevitable
that more sperm whales will strand. The hunting of sperm
whales was not banned until 1988, and it is unlikely that that
the population has been able to recover in such a short time.
Noter
1. Simmonds, M. P: The meaning of cetacean strandings,
Bulletin De L´Institut Royal des Sciences Naturelles de Bel-
gique, Biologie, 67-suppl., 1997, p. 29-34, Wright, A. J.:
Lunar cycles and sperm whales (Physeter macrocephalus)
strandings on the North Atlantic coastlines of the British Is-
les and eastern Canada, Marine Mammal Science:21 (1), p.
145-149.
2. Perrin, W. f., Geraci, J. R.: Strandings, Perring, W. F., Wür-
sig, B., Thewissen, J. G. M. (red.): Encyclopedia of Marine
Mammals, Academic Press, 2002, p. 1192-1197.
3. Perrin, W. f., Geraci, J. R: op. cit., Encyclopedia of Marine
Mammals, 2002, p. 1192-1197.
4. Sonntag, R. P., Lütkebohle, T.: Potential causes of In-
creasing Sperm Whale Strandings in the North Sea, German
Journal of Hydrography: 8, 1998, p. 29-34.
5. Kinze, C. C.: Hvalfund i arkiverne, Siden Saxo: 1, Jan.
Kvt., 16. Årg., 1999, p. 2-6.
6. Kinze, C. C.: op. cit., Siden Saxo: 1, Jan. Kvt., 16. Årg.,
1999, p. 2-6.
7. Kinze, C. C.: op. cit., Siden Saxo: 1, Jan. Kvt., 16. Årg.,
1999, p. 2-6.
8. Kinze, C. C.: Danish whale records 1575-1991 (Mamma-
lia, Cetacea). Review of whale specimens stranded, directly
or incidentally caught along the Danish coasts, Steenstrupia:
21 (2), 1995, p. 155-196.
9. Kinze, C. C.: op. cit., Siden Saxo: 1, Jan. Kvt., 16. Årg.,
1999, p. 2-6.
10. Kinze, C. C.: op. cit., Siden Saxo: 1, Jan. Kvt., 16. Årg.,
1999, p. 2-6.
11. Guldberg, M.: Hval- og sælfangerne fraVadehavet, Hahn-
Pedersen, M. (red.):Sjæk´len – Årbog for Fiskeri- og Søfarts-
museet, Saltvandsakvariet i Esbjerg 2010, Esbjerg 2011, p.
82.
12. Jensen, T., Tougaard, S.: 16 kaskelothvaler på Rømø,
Hahn-Pedersen, M. (red.): Sjæk´len – Årbog for Fiskeri- og
Søfartsmuseet, Saltvandsakvariet i Esbjerg 1996, Esbjerg
1997, p. 107-123.
13. Jensen, T., Tougaard, S.: 13 kaskelothvaler på Rømø,
Hahn-Pedersen, M. (red.): Sjæk´len – Årbog for Fiskeri- og
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