Dispersal-mediated coexistence of competing predators

Area of Science:

• Ecology
• Theoretical Ecology
• Metacommunity Dynamics

Background:

• Metapopulation models often overlook local community interactions and habitat patchiness.
• Species persistence relies on both local dynamics and inter-patch dispersal rates.

Purpose of the Study:

• To investigate how dispersal influences the coexistence of competing species in a two-patch metacommunity.
• To explore mechanisms beyond spatial asynchrony and competition-colonization trade-offs that promote regional coexistence.

Main Methods:

• Development of a mathematical model simulating two consumers competing for a shared resource across two distinct habitat patches.
• Analysis of species interactions under varying dispersal rates and patch productivities.

Main Results:

• Species can coexist via dispersal even if one is outcompeted in isolation.
• Dispersal can facilitate coexistence through synchronous oscillations or stable equilibrium.
• Increased dispersal of the superior competitor can promote the inferior competitor's persistence.

Conclusions:

• Diffusive dispersal is a key factor mediating competitor coexistence in metacommunities.
• Habitat heterogeneity and resource dynamics, influenced by dispersal, can decouple local communities and enable coexistence.