Island Biogeography and Life-History Traits Stabilize Island Bird Communities.

Area of Science:

• Island biogeography
• Community ecology
• Avian ecology

Background:

• Biodiversity-stability relationships are crucial for ecosystem functioning.
• The influence of biogeographic context on these relationships remains poorly understood.
• Islands serve as valuable model systems for ecological research.

Purpose of the Study:

• To integrate the Equilibrium Theory of Island Biogeography (ETIB) with a functional perspective.
• To explore how island biogeographic factors and biodiversity facets influence avian community stability.
• To clarify pathways through which biogeographic factors shape island community dynamics.

Main Methods:

• Conducted annual breeding bird surveys on 36 land-bridge islands over 13 years.
• Quantified avian temporal community stability, population stability, and population asynchrony.
• Tested the influence of island area, isolation, colonization/extinction rates, species richness, population size, and life-history traits on stability.

Main Results:

• Larger islands supported higher species richness, promoting population stability and asynchrony.
• Larger islands harbored larger, more stable avian populations.
• Island isolation had a weak net effect on stability; 'fast' life-history traits enhanced community stability.

Conclusions:

• Island size and habitat heterogeneity are key drivers of avian biodiversity and stability.
• Biogeographic factors and species traits interact to maintain community stability on islands.
• Findings offer insights for biodiversity conservation in fragmented landscapes.