Energy budgets for tadpoles approaching metamorphosis

We describe a dynamic energy budget (DEB) model for tadpoles over the course of metamorphosis. The model accounts for details in the tadpoles feeding behavior, as feeding and indirectly respiration are reduced in the late developmental stages preceding metamorphosis to an immature froglet. We propose two versions of our DEB model, one where the energy reserves of the organism are accounted for explicitly (a variant on Kooijman's "standard" DEB model), and one where reserves and structural biomass are lumped together so that only the size of the organism is tracked (a variant on DEBkiss). Both models are parameterized using a time series of measurements on a cohort of tadpoles of the Pacific tree frog, Pseudacris regilla. The models describe tadpoles from the middle of their development as tadpoles until they emerge as froglets. Visually, both models fit the growth and respiration empirical data reasonably well; statistically the fit to the full DEB model is slightly better. The models highlight the metabolic changes during the life of a tadpole and demonstrate how morphological changes in developing organisms can be accomodated in the DEB framework.