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P.L.M. van Dijk et al.
situation of high energy turnover. Special attention will be directed
towards potential differences between seasonal cold acclimation of
eurythermal temperate species as opposed to adaptation to the cold
environment on the evolutionary time scale in Antarctic fish.
Effect of Temperature on the Ability to Perform Exercise
The actual activity pattern and the mode of locomotion observed in fishes
depend upon the species' lifestyle. Two main types of swimming can be
distinguished. The marathon-type of performance is powered mainly by
red musculature and can be sustained for hours or even days. The maximal
sustainable speed, which is the maximum speed that can be maintained
for more than 200 min [2], is largely determined by the aerobic capacity
of the red musculature of the fish. Maximal swimming speed is reached
only for a short period of time during burst swimming when white
musculature becomes active. The white muscle relies mostly on glycolytic
energy production and therefore this fiber type is rapidly fatigued.
Acute cold exposure reduces the ability to exercise, but the negative
effect of low temperature on aerobic and anaerobic swimming
performance is compensated to various degrees during cold acclimation.
While in goldfish acclimation to 5 °e leads to almost complete
compensation of the maximal (anaerobic) swimming velocity compared to
animals acclimated to 35 °e, killifish show only moderate compensation
and no acclimatory effects were observed in trout [3,4].
Compensatory effects on the aerobic swimming capacity (maximal
sustainable speed) have been observed in several species such as goldfish,
carp and striped bass [5-7]. However, cold acclimation does not lead to
complete compensation since warm acclimated fish are able to maintain
higher swimming speeds than cold acclimated animals at their respective
acclimation temperature (Table I). Evolutionary adaptation to the polar
environment, however, may have led to a higher degree of compensation
as evidenced by a comparison of the maximal sustainable speeds from
Antarctic and temperate fish. Maximum sustainable speeds of active
pelagic Pagothenia borchgrevinki range between 1.8 and 2.15 bl sec- 1
[8,9], while benthic Notothenia coriiceps can only maintain 0.8-1.0 bl
sec- 1 [10,11]. Table 1 shows that these values are well in the range of the
maximum sustainable speeds of temperate fish species.
Burst swimming performance appears to be more constrained in polar
fish, especially in larvae and juvenile animals as opposed to adult stages.
No thermal compensation is observed in the startle response of cold
adapted Antarctic fish larvae [12].
P.L.M. van Dijk et al.
situation of high energy turnover. Special attention will be directed
towards potential differences between seasonal cold acclimation of
eurythermal temperate species as opposed to adaptation to the cold
environment on the evolutionary time scale in Antarctic fish.
Effect of Temperature on the Ability to Perform Exercise
The actual activity pattern and the mode of locomotion observed in fishes
depend upon the species' lifestyle. Two main types of swimming can be
distinguished. The marathon-type of performance is powered mainly by
red musculature and can be sustained for hours or even days. The maximal
sustainable speed, which is the maximum speed that can be maintained
for more than 200 min [2], is largely determined by the aerobic capacity
of the red musculature of the fish. Maximal swimming speed is reached
only for a short period of time during burst swimming when white
musculature becomes active. The white muscle relies mostly on glycolytic
energy production and therefore this fiber type is rapidly fatigued.
Acute cold exposure reduces the ability to exercise, but the negative
effect of low temperature on aerobic and anaerobic swimming
performance is compensated to various degrees during cold acclimation.
While in goldfish acclimation to 5 °e leads to almost complete
compensation of the maximal (anaerobic) swimming velocity compared to
animals acclimated to 35 °e, killifish show only moderate compensation
and no acclimatory effects were observed in trout [3,4].
Compensatory effects on the aerobic swimming capacity (maximal
sustainable speed) have been observed in several species such as goldfish,
carp and striped bass [5-7]. However, cold acclimation does not lead to
complete compensation since warm acclimated fish are able to maintain
higher swimming speeds than cold acclimated animals at their respective
acclimation temperature (Table I). Evolutionary adaptation to the polar
environment, however, may have led to a higher degree of compensation
as evidenced by a comparison of the maximal sustainable speeds from
Antarctic and temperate fish. Maximum sustainable speeds of active
pelagic Pagothenia borchgrevinki range between 1.8 and 2.15 bl sec- 1
[8,9], while benthic Notothenia coriiceps can only maintain 0.8-1.0 bl
sec- 1 [10,11]. Table 1 shows that these values are well in the range of the
maximum sustainable speeds of temperate fish species.
Burst swimming performance appears to be more constrained in polar
fish, especially in larvae and juvenile animals as opposed to adult stages.
No thermal compensation is observed in the startle response of cold
adapted Antarctic fish larvae [12].