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Compiled by Sidsel Grønvik
University of Tromsø, N-9037 Tromsø, Norway
This report summarises information obtained from: the University of Tromsø: the Department of Arctic Biology (UITØ-AAB) and the
Norwegian College of Fishery Science (UITØ-NFH), The Norwegian School of Veterinary Science, Department of Arctic Veterinary
Medicine, Tromsø (NVH-IAV), the Institute of Marine Research, Bergen (IMR), the Norwegian Institute of Fisheries and Aquaculture,
Tromsø (NIFA), and the Norwegian Polar Institute, Tromsø (NP).
Species and stocks studied
Common name
Minke whale
Scientific name
Balaenoptera acutorostrata
Northeast Atlantic
Items referred to
2.1.1; 2.2; 4.1; 4.2; 4.4; 6.1; 9
Humpback whale
Killer whale
White whale
Harbour porpoise
Megaptera novaeangliae
Orcinus orca
Delphinapterus leucas
Phocoena phocoena
North Atlantic
Northeast Atlantic
Norwegian coastal waters
3.1.3; 4.1; 5
2.2; 3.1.3; 3.2; 4.3; 4.4; 5
2. Sightings data
2.1 Field work
During the period 5 July to 15 August 2000 a sighting survey was conducted in Lofoten and in the Barents Sea with
exception of a southeastern area in Russian EEZ. This was the fifth year of a six-year program to cover the northeast
Atlantic to provide a new abundance estimate of minke whales every sixth year as part of the management scheme
established for this species. (IMR)
In August/September mapping of whale distributions was conducted during 0-group fish surveys in the Barents Sea.
Incidental observations of marine mammals have been collected from research survey vessels and Coastguard vessels.
Recorded data include date, position, species and numbers. (IMR)
2.2 Analyses/development of techniques
In July an experimental survey for estimating abundance of harbour porpoises in coastal waters was conducted along
the coast from Varanger to Senja in northern Norway. (IMR)
The methods for analysing sightings survey data have been further developed with respect to combining multi-year
survey data for Northeast Atlantic minke whales. (IMR)
3. Marking data
3.1 Field work
In August and September 2000 photo IDs of humpback whales were collected from the Barents Sea area and Svalbard
Area. (IMR)
In late October in Storfjorden, Svalbard three white whales were equipped with satellite transmitters to study winter
migration. (C. Lydersen, NP).
During the minke whale sightings survey (see 2.1.1) satellite tagging of large whales was conducted. (IMR)
Capture and satellite tagging studies of harbour porpoise were carried out in Varangerfjord, Northern Norway in June 2000. (IMR)
Two killer whales were instrumented with satellite tags in Tysfjord in November/December 2000. (IMR)
3.2 Analyses/development of techniques
Experiments to use by-caught harbour porpoises for satellite tagging have been successful, although only one animal
was tagged in June 2000.
The development of a satellite linked radio tag for tracking movements of cetaceans was continued in 2000. (NVHIAV)
4. Tissue/biological samples collected
4.1 Biopsy samples
Field work on white whales was conducted at Svalbard in October. A total of 8 white whales were live-captured.
Tissue and blood samples were collected for studies of genetics and pollution. (NP).
During the minke whale sightings survey (see 2.1.1.) biopsy samples were collected from several whale species.
White whale
Calendar year/
no. collected
Total holdings
Contact person/institute
C. Lydersen, Norwegian Polar
Institute, Tromsø
4.2 Samples from directed catches
During the commercial whaling season (May-June), stomach samples, body condition data and biological material for
studies of demography, reproduction and pollutants were collected from minke whales by scientific personnel on four of
the participating vessels. Additionally, tissue materials for studies of stock identity were collected by governmental
inspectors from all whales taken by the other vessels participating in the Norwegian small type whaling. (NIFA)
Biological material and especially material relevant to alternative age determination techniques for baleen whales was
collected during the commercial minke whale catch operations in the Jan Mayen area and in the North Sea. (IMR)
Samples for pathological studies were collected from 19 minke whales during the 2000 catch operations. The studies
include gross post mortem examinations in the field and histological examinations of tissues from vital organs. (NVHIAV).
4.3 Samples from stranded animals
Samples from stranded harbour porpoises have been analysed to study population structure in the North Atlantic (see
4.4, IMR).
4.4 Analyses/development of techniques
Studies of a number of alternative methods, including an evaluation of current methods for age determination of
minke whales have been continued. The use of fatty acids, mandibular growth zones and eye lense aspartic acid show
promising results. The use of digital image analysis as a tool in age estimations is being developed.(IMR)
Stomach content samples from minke whales have been analysed using traditional methods where the original
biomass of prey items are reconstructed based on remaining hard parts in the contents. Acoustics and biological data
from prey estimate surveys on the whaling grounds have also been analysed. (NIFA)
Substantial changes have occurred in the Barents Sea ecosystem over the past 30 years, the most conspicuous being
related to the rises and falls of stocks of the two dominant pelagic shoaling fish species: capelin and herring. Based on
data from annual studies, effects of these ecological changes on the diet and food consumption of minke whales were
assessed for the period 1992-1999. Following a collapse in the capelin stock in 1992/1993, minke whales foraging in
the northern Barents Sea apparently switched from a capelin-dominated diet to a diet almost completely comprised of
krill. The southern region of the Barents Sea include important nursery areas for the Norwegian spring spawning
herring. Good recruitment to this stock gives strong cohorts and large numbers of young, adolescent herring (0-3
years old) which serve as the main food for minke whales feeding in the area. Recruitment failure with subsequent
weak cohorts seems, however, to reduce the availability of adolescent herring to such an extent that minke whales
switch to other prey items such as krill, capelin and, to some extent, gadoid fish. The annual changes in prey
abundance and whale body condition, measured as girth and blubber index, was weakly correlated. Apparantly,
however, immature animals and adult females seemed to be in better condition in years with good abumndance of
immature herring in the southern Barents Sea. (NIFA)
Stomach content samples from 33 minke whales caught during the Norwegian commercial whaling in the period MayJune 1998, were collected in four sub areas in the southern Barents Sea. Simultaneously, a comprehensive resource
survey was conducted in order to identify and estimate the abundance of potential prey items for the whales in the
four sub areas. The small scale resource surveys revealed significant variations in absolute and relative prey
abundance between sub areas, while the temporal (1-7 days) variations in absolute prey abundance within sub areas
appeared to be insignificant for all prey items except herring and, perhaps, capelin. This was, to some extent, also
refelected in the whale diets. Krill dominated the minke whale diets in all but one sub area, but pelagic fish such as
capelin and herring also contributed significantly. The apparent monophagus feeding of the whales resulted in narrow
niche widths in all sub areas investigated, including also the medium scale area resulting from pooling of all sub
areas. The results from the resource survey showed that krill was by far the most important prey item in all areas,
followed by either saithe, herring or haddock, depending on sub area. The results from the prey preference analysis
gave evidence that the whales may have selected capelin actively. Gadoids (cod, haddock, saithe) appeared to have
been avoided, while krill appeared to have been either avoided, fed randomly, or preferred, depending on sub area
and analysis level. (NIFA, UITØ-NFH)
Stomach content samples from 23 minke whales, caught during the Norwegian commercial whaling in the period
May-June 1999, were collected in two areas in the southern Barents Sea, and compared with results from a
simultaneous comprehensive resource survey designed to identify and estimate the abundance of potential prey items
for the whales. The small-scale resource surveys revealed significant variations in absolute and relative prey
abundance both between areas and, temporally, within areas. As in 1998, this was also reflected in the whale diets,
which was particularly dominated by herring and capelin. Both these prey items were subjected to population
specialisation, i.e., they were taken frequently by many whales. Using the obtained data on diet and prey abundance to
assess quantitatively possible prey selectivity of the minke whales in the area, it appears that capelin was preferred
over all other prey items. The results from the 1998 and 1999 minke whale prey preference studies are now being
subject to final analyses in a PhD project. (NIFA, UITØ-NFH)
Based on tissues samples collected for scientific purposes during Norwegian and Greenland whaling operations in
1998, questions concerning minke whale stock identity were addressed in a joint Greenland-Norwegian program. The
methods applied included analyses of DNA, organochlorines, heavy metals and fatty acid signatures. Some
preliminary results were presented at the 2000 meeting of the Scientific Committee of IWC, and the final analyses are
still in progress. (NIFA, IMR)
Using mitochondrial DNA sequencing of the control region, population structure in the North Atlantic harbour
porpoises has been investigated in two separate studies based on material collected from strandings and bycatches.
Firstly, data were obtained from samples collected in the Barents Sea, the Norwegian North Sea, and the Scottish
North Sea. Control region sequences of 149 harbour porpoises were sequenced and these sequences compared
among regions. Further, the genetic population structure of harbour porpoises from the entire North Atlantic was
investigated by increasing the study area from which samples were compared to six regions (Norway, Iceland,
Greenland, Newfoundland, Gulf of St. Lawrence, Gulf of Maine). mtDNA haplotypes from 370 individuals were
compared among these three regions. Sequencing of the mitochondrial control region suggest that the North Sea UK
and the Barents Sea subpopulations should be considered separate management units. In addition, haplotype
frequency differences among the North Sea Norway and North Sea UK females (excluding Shetlands) also suggest
the presence of separate management units within the North Sea. In a study comparing mitochondrial DNA sequences
across the North Atlantic the largest significant differences occurred between Norway and the Gulf of Maine
suggesting a limited amount of overall trans-Atlantic gene flow. Further, significant differences were found for
haplotype frequencies and molecular diversity (FST and ST) between Iceland and Norway suggesting the existence of
a discontinuity in the North Atlantic between Iceland and Norway. (IMR)
5. Pollution studies
Samples from 8 white whales live-captured at Svalbard were taken for, amongst other, studies of pollution. (NP).
Geographic variation in the levels of radioactive caesium ( 137Cs) were examined in axial muscle from 36 bycaught
harbour porpoises from five locations along the coast of Norway, ranging from southern Norway (North Sea) to
northern Norway (Barents Sea). Levels of 137Cs in seawater and sediments have been found to differ along the coast
of Norway due to distance from point sources, such as the Sellafield nuclear reprocessing plant on the Irish Sea, and
Chernobyl run-off into the Baltic Sea. Radioactive caesium is accumulated in the muscle in a manner consistent with
ambient levels in the environment and/or through ingestion of contaminated prey items. Hence, if harbour porpoises
are resident in an area, their muscle tissue would reflect the ambient differences in 137Cs. The levels found in harbour
porpoise muscle were consistent with that found in the area from which they were bycaught. Porpoises from the
Barents Sea had significantly lower levels of 137Cs than porpoises from the west coast and the south coast. Further,
porpoises from the south coast had significantly higher levels than all other regions. This suggests the presence of
population sub-structuring on an ecological time scale and that harbour porpoises are limited in their movements
along the coast of Norway, suggesting that sub-populations may be present on a finer scale. (IMR)
6. Statistics for large cetaceans
6.1 Direct catches for the calendar year 2000
Type of catch
Minke whale
Small-type whaling
Management Areas
Total catch
8. Strandings
Information on strandings has been collected by the Institute of Marine Research, Bergen, Norway.
9. Other studies and analyses
The development of the new Norwegian penthrite grenade for minke whales was concluded after the 1999 season
During the whaling season in 2000 the new grenade was implemented in the hunt under the name of "Whalegrenade99" and the previous penthrite grenade, developed in 1984 was banned. The grenade was used on all Norwegian
vessels used for minke whale hunt in 2000. The results as to instantaneous death were superior to all previous results
obtained in the Norwegian minke whale hunt. (IAV-NVH)
A total of 373 serum samples from minke whale (216), fin whale (108) and sei whales (49), all caught between 1983
and 1996 during commercial and scientific whaling activity west off Iceland (fin and sei whales), the coast of Norway
and Kola Peninsula (Russia), Spitsbergen, and Bear Island (minke whales), were tested for Brucella antibodies, which
were found in all species (13%, 11% and 14%, respectively).
Tissue samples from 14 fin, 5 sei and 10 minke whales were tested for the presence of Brucella, and isolates were
obtained from the liver and spleen of one minke whale from Finnmark, Norway. The potential pathogenicity of this
group of bacteria for marine mammals remains unclear, but infection may be associated with reproductive failure, as
reported for bottlenose dolphins in captivity. (IAV-NVH)
Serum samples collected from 14 minke whales caught during commercial catch operations in 1997 and 28 in 1998
off the coast of Finnmark, Norway, during May to July, have been analysed. For some parameters, serum
biochemistry values varied with the degree of hemolysis, lipemia and storage time at –20 C. A huge individual
variation was found for some parameters, especially enzymes. (IAV-NVH)
11. Publications
11.1 Published or ‘In Press’
Andersen, G, Kovacs K.M., Lydersen, C., Skaare, J.U., Gjertz, I. and Jenssen, B.M. 2001.Concentrations and patterns
of organochlorine contaminants in white whale (Delphinapterus leucas) from Svalbard, Norway. Sci Total
Environ 2001; 264: 267 - 281
Bjørge, A. in press. How stable are marine mammal habitats in an ocean of variability? In: P. Evans and A. Raga
(eds) Marine Mammals: Biology and Conservation. Plenum Books.
Bjørge, A. and Tolley, K. in press. The harbor porpoise. In: Encyclopedia of Marine Mammals. MMS.
Blix, A.S., Folkow, L.P. & Sørlie, D. 2000. Simulations of the effect of currently used grenade harpoons for
the killing of whales using a pig-model. Acta Vet. Scand. 41: 237-242.
Bogstad, B, Haug, T. & Mehl, S. 2000. Who eats whom in the Barents Sea? NAMMCO Scientific Publications 2: 98119.
Boily, P., Kvadsheim, P.H. & Folkow, L.P.. 2000. Experimental validation of a cutaneous heat flux model to
predict metabolic rates of marine mammals. J. theor. Biol. 207: 317-323.
Clavareau, C., Wellemans, V., Walravens, K., Tryland, M., Verger, J-M., Grayon, M., Cloeckaert, A., Letesson, J-J., and
Godfroid, J. 1998. Phenotypic and molecular characterization of a Brucella strain isolated from a minke whale
(Balaenoptera acutorostrata). Microbiology 144: 3267-3273.
Dahl, T. M., Lydersen, C. , Kovacs, K.M., Falk-Petersen, S., Sargent, J., Gjertz, I. & Gulliksen, B. 2000:
Fatty acid composition of the blubber in white whales (Delphinapterus leucas). Polar Biol. 23: 401409.
Folkow, L.P., Haug, T., Nilssen, K.T. & Nordøy, E.S. 2000. Estimated food consumption of minke whales Balaenoptera
acutorostrata in northeast Atlantic waters in 1992-1995. NAMMCO Scientific Publications 2: 65-81.
Haug, T. and Damsgård, B. (eds.) Spekkhogger – Staurkval . Ottar 230. 46 pp. [In Norwegian, containing 7 popularised
papers on killer whales].
Janik, V.M., Van Parijs, S.M. & Thompson, P.M. 2000: A two – dimensional acoustic localization system
for marine mammals. Mar. Mammal Sci. 16: 437-447.
Oksanen, A., Tryland, M., Johnsen, K. & Dubey, J. P. 1998. Serosurvey of Toxoplasma gondii in North Atlantic marine
mammals by the use of agglutination test employing whole tachyzoites and dithiothreitol. Comparative
Immunology, Microbiology and Infectious Diseases, 21: 107-114.
Olsen, M.A., Blix, A.S., Aagnes, T.H., Sørmo, W. & Mathiesen, S.D. 2000. Chitinolytic bacteria in the
minke whale forestomach. Canadian Journal of Microbiology 46: 85-94.
Olsen, M.A. & Mathiesen, S.D. 2000. Forestomach digestion in whales – terrestrial adaptation in marine environment.
In: Effects of antinutrients on the nutritional value of legume diets (eds. Krogdahl, Å., Mathiesen, S.D., Pryme,
I.F.), COST 98, Vol. 8, Office for Official Publications of the European Communities, Luxembourg, pp. 96-102
Schweder, T. 2000. Distortion of Uncertainty in Science: Antarctic Fin whales in the 1950s. Journal of International
Wildlife Law and Policy. 3 (1): 73-92.
Schweder, T., Hagen, G.S. and Hatlebakk, E. 2000. Direct and indirect effects of minke whale abundance on cod and
herring fisheries: A scenario experiment for the Greater Barents Sea. NAMMCO Scientific Publications 2: 121132.
Tryland, M. and Brun, E. 2001. Serum chemistry of the minke whale in the northeastern Atlantic. Journal of Wildlife
Diseases 37(2): 332-341.
Tryland, M., Kleivane, L., Alfredson, A., Kjeld, M., Arnason, A., and Godfroid, J. 1999. Evidence of Brucella infection
in marine mammals in the North Atlantic Ocean. Veterinary Record 144: 588-592.
Van Parijs S.M., Parra G. & Corkeron, P.J. 2000: Sounds produced by Australian Irrawaddy dolphins, Orcaella
brevirostris. J. Acoust. Soc. Am.. 108: 1938-1940.
11.2 Unpublished literature
Andersen, L.W., Born, E.W., Dietz, R., Haug, T., Øien, N. & Bendixen, C. 2000. Population structure of Greenland and
Atlantic minke whales (Balaenoptera acutorostrata) based on sequence variation of the D-loop of mtDNA and
DNA microsatellite variation. Paper SC/52/AS8 presented to the International Whaling Commission.
Bjørge, A., Øien, N. and Donavan, G. 2000. Surveys to estimate abundance of small inshore cetaceans, SEASIC.
Paper SC/52/O14 presented to the International Whaling Commission.
Heide-Jørgensen, M.P., Kleivane, L., Øien, N., Laidre, K.L., and Jensen, M.V. 2000. Autumn Movements of a Blue
Whale (Balaenoptera musculus) in the North Atlantic. Paper SC/52/OS1 presented to the International Whaling
Heide-Jørgensen, M.P., Nordøy, E.S., Øien, N., Folkow, L.P., Kleivane, L., Blix, A.S., Jensen, M.V., and Laidre,
K.L. 2000. Satellite tracking of minke whales (Balaenoptera acutorostrata) off the north Norwegian coast.
Paper SC/52/O13 presented to the International Whaling Commission.
Hobbs, K.E., Muir, D.C.G., Born, E.W., Dietz, R., Haug, T., Metcalfe, T., Metcalfe, C. & Øien, N. 2000. Using
persistent organochlorine levels and patterns to identify minke whale (Balaenoptera acutorostrata) stocks from
the North Atlantic. Paper SC / 52 / AS10 presented to the International Whaling Commission.
Karlsen, J., Bisther, A., Lydersen, C., Kovacs, K. & Haug, T. 2000. Vocalisation of white whales (Delphinapterus
leucas) summering around Svalbard. 14th Annual Conference of the European Cetacean Society, Cork,
Ireland, 2-5th April 2000. Poster & Abstract.
Kovacs, K. M. & Lydersen, C. 2000: A summary of white whale (Delphinapterus leucas) studies in Svalbard,
Norway - and future research directions. Paper SC/52/SM2 presented to the International Whaling
Lindstrøm, U., Harbitz, A., Haug, T. & Pedersen, T. 2000. Foraging behaviour of minke whales (Balaenoptera
acutorostrata) in the southern Barents Sea. ICES CM 2000 / Q:07: 21 pp.
Lindstrøm, U. & Haug, T. 2000. Feeding strategy and prey selectivity in minke whales (Balaenoptera acutorostrata)
foraging in the southern Barents Sea during early summer. Paper SC/52/E14 presented to the International
Whaling Commission.
Lindstrøm, U., Haug, T. & Røttingen, I. 2000. Consumption of herring Clupea harengus by minke whales Balaenoptera
acutorostrata in the Barents Sea. HERRING2000, 18th Wakefield Fisheries Symposium, Anchorage, Alaska in
early February 2000: 19 pp.
Lydersen, C. & Kovacs, K. M. 2000: Studies of white whales (Delphinapterus leucas) in Svalbard, Norway. Marine
mammals of Holarctic. Int. Sci. Conf. Arkhangelsk 21-23 Sept. 2000. Sum. Rep., p.25.
Møller, P., Born, E.W., Dietz, R., Ruzzante, D., Haug, T. & Øien, N. 2000. Differences in fatty acid composition of
blubber in minke whales (Balaenoptera acutorostrata) from Greenland, the NE Atlantic Ocean and the North
Sea, 1998. Paper SC/52/AS9 presented to the International Whaling Commission.
Olsen, M.A. 2000. Microbial digestion in reindeer and minke whales. Dr.philos. thesis, University of
Tromsø, Tromsø, Norway. 119 pp.
Outridge, P. Asmund, G., Born, E.W., Dietz, R., Haug, T., Riget, F. & Øien, N. 2000. Stock discrimination of minke
whales (Balaenoptera acutorostrata) in West Greenland and the North Atlantic using tissue element and lead
isotope signatures. Paper SC/52/AS11 presented to the International Whaling Commission. 10 pp.
Polacheck, T., Palka, D., Borchers, D., Cooke, J.G., Skaug, H.J. & Dixon, C. 2000. Simulation comparison of
different methods for estimating whale density from double team line transect data. Paper SC/52/RMP18
presented to the International Whaling Commission.
Schweder, T. and Ianelli J.N. 2000. Assessing the Bering-Chukchi-Beaufort Seas stock of bowhead whales from survey
data, age-readings and photo-identifications using frequentist methods. Paper SC/52/AS13 presented to the
International Whaling Commission.
Schweder, T. 2000. Abundance estimation from photo-identification data: confidence distributions and reduced
likelihood for bowhead whales off Alaska. Paper SC/52/AS14 presented to the International Whaling
Skaug, H.J. 2000. Combination of multiyear surveys for Northeastern Atlantic minke whales. Paper SC/52/RMP12
presented to the International Whaling Commission.
Skaug, H. J. 2000. "Nonlinear state space models in fisheries assessment". Presented at Workshop on marine spatial
modelling, Bergen, 6-8 March, 2000.
Ugarte, F. & Haug, T. 2000. A quantitative study of the behaviour of killer whales in North Norway. 14 th Annual
Conference of the European Cetacean Society, Cork, March 2000. Abstract.
Øien, N. 2000. Report of the Norwegian 1999 sighting survey for minke whales. Paper SC/52/RMP13 presented to the
International Whaling Commission.
Øien, N. 2000. Hval i Toresen R. et al. 2000, Havets ressurser, 2000, FiskenHav, Særnr. 1: 41-46. [In Norwegian]