Comparative metabolic rates of common western North Atlantic Ocean sciaenid fishes

The resting metabolic rates ( R R ) of western North Atlantic Ocean sciaenids, such as Atlantic croaker Micropogonias undulatus , spot Leiostomus xanthurus and kingfishes Menticirrhus spp., as well as the active metabolic rates ( R A ) of M. undulatus and L . xanthurus were investigated to facilitate inter and intraspecific comparisons of their energetic ecology. The R R of M. undulatus and L . xanthurus were typical for fishes with similar lifestyles. The R R of Menticirrhus spp. were elevated relative to those of M. undulatus and L . xanthurus , but below those of high‐energy‐demand species such as tunas Thunnus spp. and dolphinfish Coryphaena hippurus . Repeated‐measures non‐linear mixed‐effects models were applied to account for within‐individual autocorrelation and corrected for non‐constant variance typical of noisy R A data sets. Repeated‐measures models incorporating autoregressive first‐order [AR(1)] and autoregressive moving average (ARMA) covariances provided significantly superior fits, more precise parameter estimates ( i.e. reduced s.e .) and y ‐intercept estimates that more closely approximated measured R R for M. undulatus and L . xanthurus than standard least‐squares regression procedures.