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C. Zimmermann and G. Hubold
activity effects on the standard metabolism. Standard metabolism is
defined as the metabolism without any external or internal work, i.e.
without spontaneous activity. Ideally, the complete range of fish species
from polar, temperate and tropical environments should be investigated to
separate the effect of temperature from the ecologically determined
("mode of life") effect on the metabolism. A quantitative criterium for
activity and life type should be developed which surpasses the simple
subjective consideration of a fish's "mode of life" as just being "sluggish"
or "active."
The aim of the present study was to link behavioral activity (as
expressed e.g. by movements) and metabolic activity (in terms of oxygen
consumption) of different fish species from both polar seas. The
quantitative effects of a fish's activity on its metabolism are presented by
means of multivariate statistics. The consequences for the three competing
concepts on fish metabolism are discussed. These concepts are:
• The standard oxygen consumption (SOC) is strictly related to the
thermodynamic principle given by the environmental temperature. This
should hold true, if a proper account for the exclusion of spontaneous
activity, stress etc. is made in the experimental set-up.
• Polar fishes deviate from the thermodynamic principle by an elevated
standard metabolism: the metabolic cold adaptation concept [10-12].
• The "mode of life" is the dominant factor determining the SOC of
fishes; the "mode of life" can be expressed by the level of spontaneous
activity.
Material and Methods
Experiments were conducted at two field stations (European Large Scale
Facility Ny-Alesund, Spitsbergen: June-August 1994, US McMurdo
Station, Ross Sea/Antarctica: January-February 1995) and at the home
laboratory in Kie1 (January-June 1996). At field stations fish were caught
in traps and fyke nets; the species measured at the Kiel lab were obtained
from bottom trawls, conducted from RV "Polarsten" during various cruises
to the Antarctic (for more detailed information see [9]). Seven fish species
were chosen to cover a wide range of different ecotypes: the cryopelagic
hunters Boreogadus saida (polar cod, Gadidae) from the Arctic, and
Pagothenia borchgrevinki (Nototheniidae) from the Antarctic; three
demersal species, Anarhichas minor (Anarhichadidae), Trematomus
bernacchii (Nototheniidae) and Gymnodraco acuticeps (Bathydraconidae);
and two strictly benthic forms, the Arctic sculpin Myoxocepha/us scorpius
(Cottidae) and the Antarctic genus Pogonoph,yne (Artedidraconidae). The
C. Zimmermann and G. Hubold
activity effects on the standard metabolism. Standard metabolism is
defined as the metabolism without any external or internal work, i.e.
without spontaneous activity. Ideally, the complete range of fish species
from polar, temperate and tropical environments should be investigated to
separate the effect of temperature from the ecologically determined
("mode of life") effect on the metabolism. A quantitative criterium for
activity and life type should be developed which surpasses the simple
subjective consideration of a fish's "mode of life" as just being "sluggish"
or "active."
The aim of the present study was to link behavioral activity (as
expressed e.g. by movements) and metabolic activity (in terms of oxygen
consumption) of different fish species from both polar seas. The
quantitative effects of a fish's activity on its metabolism are presented by
means of multivariate statistics. The consequences for the three competing
concepts on fish metabolism are discussed. These concepts are:
• The standard oxygen consumption (SOC) is strictly related to the
thermodynamic principle given by the environmental temperature. This
should hold true, if a proper account for the exclusion of spontaneous
activity, stress etc. is made in the experimental set-up.
• Polar fishes deviate from the thermodynamic principle by an elevated
standard metabolism: the metabolic cold adaptation concept [10-12].
• The "mode of life" is the dominant factor determining the SOC of
fishes; the "mode of life" can be expressed by the level of spontaneous
activity.
Material and Methods
Experiments were conducted at two field stations (European Large Scale
Facility Ny-Alesund, Spitsbergen: June-August 1994, US McMurdo
Station, Ross Sea/Antarctica: January-February 1995) and at the home
laboratory in Kie1 (January-June 1996). At field stations fish were caught
in traps and fyke nets; the species measured at the Kiel lab were obtained
from bottom trawls, conducted from RV "Polarsten" during various cruises
to the Antarctic (for more detailed information see [9]). Seven fish species
were chosen to cover a wide range of different ecotypes: the cryopelagic
hunters Boreogadus saida (polar cod, Gadidae) from the Arctic, and
Pagothenia borchgrevinki (Nototheniidae) from the Antarctic; three
demersal species, Anarhichas minor (Anarhichadidae), Trematomus
bernacchii (Nototheniidae) and Gymnodraco acuticeps (Bathydraconidae);
and two strictly benthic forms, the Arctic sculpin Myoxocepha/us scorpius
(Cottidae) and the Antarctic genus Pogonoph,yne (Artedidraconidae). The