Energetic dynamics and anuran breeding phenology: insights from a dynamic game

We designed a dynamic optimization model to examine anuran-breeding phenolo gies. We evaluated the fitness consequences for males adopting one of four alternative strategies: calling, satelliting, foraging, or hiding. Various factors potentially influence male behavior, including energy reserves, pre dation risk, cost of calling, probability of finding food, distribution of male energy states in the population, and probability of surviving to anoth er breeding season. We manipulated these parameters to determine how strong ly each affects breeding phenology and chorus structure. Manipulating param eters related to the energetic costs and benefits of individual decisions, we generated the three basic patterns of anuran breeding phenology: explosi ve, continuous, and prolonged breeding with episodic chorusing. Increasing the probability of successful foraging caused a shift from an explosive pat tern to a prolonged, episodic chorusing pattern. Decreasing the calling cos t resulted in continuous chorusing. Our model predicted that satelliting wi ll be a rare strategy adopted by individuals with relatively low energy res erves. Additionally, individuals adopting the satellite strategy should alt ernate among satelliting, foraging, and calling as their energy reserves fl uctuate. Our results suggest that energetic costs of reproduction and resou rce limitation may be crucial factors influencing the phenology of anuran c horusing. We propose that under varying conditions of resource availability , male decisions are the consequence of two strategies: a starvation minimi zation strategy and an energy-state maximization strategy.