
Fig. 7. O2 consumption rates (ml O2 kg1 h1) of Lolliguncula brevis and various fishes plotted against swimming speed. Swimming speeds are expressed in (A) cm s1 and (B) body lengths s1. The 7.8, 15 and 31 g L. brevis in the figure correspond to the 4.8, 5.3 and 7.5 cm dorsal mantle length (DML) squid, respectively, depicted in Fig. 3. These squid were selected as representative of this study because they were particularly cooperative and their O2 consumption rates were close to the mean O2 consumption rates for their respective size classes. Squid mantle lengths (ML) were converted to body lengths (BL) using the equation BL=1.6ML derived from morphological measurements of L. brevis. The masses of menhaden and flounder (denoted with asterisks) were adjusted to 15 g using the equation: R=aMb, where R is metabolic rate (ml O2 kg1 h1), M is organism mass (kg), a is the mass coefficient and b is the mass exponent (0.25) (ODor and Webber, 1986). Moreover, flounder oxygen consumption rate was converted to 25°C using data on the effects of temperature on the active metabolic rate of flounder (Duthie, 1982). Sources of the data are listed in the figure.