Comparison of Bioenergetics Parameters from Two Spring-Fed Riverine Largemouth Bass Populations

Abstract

This study applies a new bioenergetics modeling framework put forth by Walters and Essington (this volume) which estimates bioenergetics parameters and consumption rates of fishes using commonly collected size-at-age and capture-recapture data from field studies. Bioenergetics model parameters and consumption rates are estimated for two populations of largemouth bass Micropterus salmoides with observed differences in growth patterns. We also compare consumption estimates from the bioenergetics model formulated by Walters and Essington with a more commonly employed bioenergetics model. We show that bioenergetics model parameters can be estimated with limited data on size-at-age and incremental growth when informative prior distributions on metabolic parameters are used. The general bioenergetics model revealed differences in bioenergetics parameters between the two largemouth bass populations that are well supported by auxiliary data on largemouth bass diets and observed prey abundance patterns. Lifetime growth and consumption estimates between the general bioenergetics model and Wisconsin bioenergetics model differed slightly. However, seasonal patterns in growth and consumption rates differed drastically between the two models. Estimating bioenergetics parameters using field data collected on specific populations of interests has the potential to allow for more realistic representation of seasonal growth and consumption patterns.

How can bioenergetics help us predict changes in fish growth patterns?

“…However activity costs were also higher because larger lake trout were maladapted to finescale movements associated with finding and consuming smaller prey Sherwood et al, 2002). Similarly, Tetzlaff et al (2010) found that a largemouth bass (Micropterus salmoides) population with insufficient abundance of large prey exhibited a much lower allometric anabolic scaling factor (d) than a nearby population with abundant large prey, presumably because energy densities of prey are insufficient to promote growth and due to increased foraging costs associated with attacking many small prey items. Understanding and appropriately accounting for ontogenetic diet or habitat shifts will be necessary in resolving these issues (e.g.…”