Optimal feeding under stoichiometric constraints: a model of compensatory feeding with functional response

Abstract

When the nutrient content of food is limited, herbivores often increase their feeding rates. Such an increase in the feeding rate is called 'compensatory feeding'. Although it has a number of implications for herbivore population and plant-forager dynamics, the compensatory feeding is not yet functionally formulated especially in relation with ecological stoichiometry. Therefore, we constructed a simple mathematical model by incorporating the optimal feeding rate into the type II functional response to maximize a forager's growth rate under constraints of carbon or nutritionally important element like phosphorus (P). We used the planktonic herbivore Daphnia as a model herbivore. The model revealed that the optimal feeding rate increased by using excess carbon when relative P content of food was less than a certain level, which is known as the threshold elemental ratio. This level changed with the change of food abundance. It also showed that whether or not foragers should exhibit compensatory feeding depends on their stoichiometric characteristics and digestive traits, and also on the assimilability of a given food. These findings are helpful to test the feeding conditions under which compensatory feeding is advantageous for a given animal. Our model can be easily incorporated into forager population dynamics and prey-consumer interaction models because the optimal feeding rate can be analytically given.

The stoichiometric legacy of fire regime regulates the roles of micro‐organisms and invertebrates in decomposition

“…), such that the invertebrates in 4yB experimental plots might have consumed larger amounts of low‐quality litter to obtain the required amount of P (Suzuki‐Ohno et al. , Jochum et al. ).…”

“…Thus, invertebrates may consume greater amounts of a low‐quality resource to obtain the required amount of a limiting nutrient (Suzuki‐Ohno et al. , Jochum et al. ).…”

Food quality and food threshold: implications of food stoichiometry to competitive ability of herbivore plankton

“…The slopes of these Daphnia species might have been even lower if they had not exhibited compensatory feeding. Although knowledge is still limited on compensatory feeding (Suzuki-Ohno et al 2012) and metabolic P loss (He and Wang 2007) of consumer animals, our study clearly showed that the TFC and growth response to food abundance were both affected by food P content through feeding performance for P acquirement and metabolic loss processes for maintenance. Gliwicz (1990) suggested that differences in TFC among species were related to body size, and there was a negative correlation between TFC and body size for Daphnia.…”

“…1c). Ironically, although compensatory feeding functions to maximize the growth rate under low P content food (Suzuki-Ohno et al 2012), it may make the consumer species inferior when there is a competitor.…”

Microzooplankton Stoichiometric Plasticity Inferred from Modeling Mesocosm Experiments in the Peruvian Upwelling Region

“…Variable phytoplankton elemental composition is often presumed to propagate across trophic levels in the food chain (Mitra and Flynn, 2007;Malzahn et al, 2010;Iwabuchi and Urabe, 2012b;Meunier et al, 2012a). Stoichiometric plasticity in (meso-) zooplankton seems to be both narrower and more complex than in phytoplankton (Sterner and Elser, 2002;Urabe et al, 2002a,b;Iwabuchi and Urabe, 2012a,b;Suzuki-Ohno et al, 2012;Hessen et al, 2013). However, most evidence is from marine zooplankton laboratory cultures and field data on stoichiometric variations in freshwater zooplankton, e.g., Daphnia phosphorus content and its variation in response to resource phosphorus-to-carbon (P:C) ratios (DeMott and Pape, 2005).…”