Light and nutrient supply mediate intraspecific variation in the nutrient stoichiometry of juvenile fish

摘要: Intraspecific variation in the nutrient stoichiometry of animals and their waste products can be substantial, but factors mediating this are unclear. We experimentally manipulated light, supply, ratio (N:P) a field experiment to generate algal quantity elemental composition, assessed stoichiometric responses juvenile carnivorous fish (bluegill, Lepomis macrochirus). Algal (primary production) (ratios carbon [C], nitrogen [N], phosphorus [P]) varied greatly response manipulations, as did bluegill body excretion stoichiometry. primary production (PPr) was greatest at high light P supply (HL HP). responded accordance with light:nutrient hypothesis; that is, C:P ratios were highest HL LP lowest LL HP. Variation strongly related basal resource (PPr), while driven by both PPr Bluegill growth C N concentrations HN LN, whereas showed opposite pattern. Thus, C:P, C:N, N:P under LN. Per capita rates mass hence HN, where grew largest. However, normalized for increased phytoplankton zooplankton production. In ecological theory, (algal) decreased estimated ingestion. single cohort comparable or exceeded observed other studies across multiple ecosystems. Our results illustrate pronounced intraspecific carnivore function quality.