Modeling the costs and benefits of seed scatterhoarding to plants

Abstract

Many plants interact with scatterhoarding animals as mutualists (seed dispersers) and antagonists (seed predators) simultaneously, but the net effects of scatterhoarding animals are rarely measured. In seed‐dispersal mutualisms, plant benefits (recruitment) received from dispersal agents should outweigh the costs, resulting in a relative fitness gain. Otherwise, plant populations cannot be sustained and would go extinct. Here we present a framework to quantify costs and benefits of scatterhoarding for animal‐dispersed plants and propose three models with the three separate scales (seed, tree and population) to quantify the costs and benefits for plants from scatterhoarding rodents. Since scatterhoarding is an adaptive dispersal strategy for many large‐seeded plants, tree‐ and population‐based models are needed to determine the costs and benefits for the plants. In the models presented here, all relevant parameters can be measured by regular surveys. Our tree‐ and population‐based models can be extended to seed plants that have dispersal agents other than scatter hoarding rodents.

Keywords

• benefits
• costs
• mutualism
• plant fitness
• seed dispersal by animals
• seed predation