Swimming Speed and Oxygen Consumption in the Bathypelagic MysidGnathophausia ingens

Abstract

The energetic costs of swimming were deter mined for the bathypelagic mysid Gnathophausia ingens. Individuals over a large size range spontaneously swam at speeds from 5 to 6.5 cm/s. To maintain this speed, smaller animals swam at much higher relative swimming speeds than did larger animals. Routine rates of oxygen consumption were thus considerably higher in the smaller instars. The relationship between standard rates of oxygen consumption and animal size was slightly less than the standard log-log allometric slope of 0.75. Within the speed range of 0-8 cm/s, oxygen consump tion appeared to increase as a linear function of speed. Cost of transport was very high at low speeds. At 5.5 cm/ s, cost of transport was lower than that measured for other crustaceans, but higher than that of fish. Swim ming efficiency increased with speed. While the lower cost of transport and higher swimming efficiency may contribute to G. ingens ' reduced rates of oxygen con sumption as compared to those of shallower-living crus taceans, the major factor appears to be G. ingens' lower level of swimming activity.

Swimming Speed and Metabolic Rate during Routine Swimming and Simulated Diel Vertical Migration of Sergestes similis in the Laboratory

“…The lower rates reported earlier represent metabolism under restricted activity and likely fall between true routine metabolism and standard metabolism. The same effect was observed in another midwater species, the bathypelagic mysid Gnathophausia ingens (Cowles and Childress 1988). Indeed, the routine rates reported here are also likely to be underestimates of the in situ rate of routine metabolism because the animal swimming in situ would experience additional drag from its trailing second antennae.…”

“…The swim tunnel (Cowles et al 1986, Cowles andChildress 1988) was a closed, recirculating system ( Figure 2). Total water volume was 4.2 liters.…”

Food utilization of two pelagic crustaceans in the Greenland Sea: Meganyctiphanes norvegica (Euphausiacea) and Hymenodora glacialis (Decapoda, Caridea)

“…In laboratory experiments northern krill increased respiration rates during extended swimming by 60% over routine metabolic rates (Saborowski 2004). Similar results were found in another euphausiid and some mysids (Torres & Childress 1983, Cowles & Childress 1988, Buskey 1998. Accordingly, elevated activities of digestive proteolytic enzymes are suitable to rapidly and efficiently utilize prey and, thus, to fuel the additional metabolic energy demands for vertical migration and the active life style in general.…”

Energetic cost of position-holding behavior in the planktonic mysid Mysidium columbiae

“…2). Sim~lar linear relationships between swimming speed and respiration have been found in other free swimming crustaceans including the amphipod Gamnlarus oceanicus (Halcrow & Boyd 1967), the euphausiid E. pacifica (Torres & Childress 1983), the mysid Gnathophausia ingens (Cowles & Childress 1988) and the copepod D. oculata (Buskey 1998).…”