Food‐Dependent Growth Leads to Overcompensation in Stage‐Specific Biomass When Mortality Increases: The Influence of Maturation versus Reproduction Regulation

Abstract: We analyze a stage‐structured biomass model for size‐structured consumer‐resource interactions. Maturation of juvenile consumers is modeled with a food‐dependent function that consistently translates individual‐level assumptions about growth in body size to the population level. Furthermore, the model accounts for stage‐specific differences in resource use and mortality between juvenile and adult consumers. Without such differences, the model reduces to the Yodzis and Innes (1992) bioenergetics model, for which we show that model equilibria are characterized by a symmetry property that reproduction and maturation are equally limited by food density. As a consequence, biomass production rate exactly equals loss rate through maintenance and mortality in each consumer stage. Stage‐specific differences break up this symmetry and turn specific stages into net producers and others into net losers of biomass. As a consequence, the population in equilibrium can be regulated in two distinct ways: either ...