Post-Larval Processes Reduce the Diversity of Coral Reef Fish Communities

Area of Science:

• Marine Ecology
• Ichthyology
• Biodiversity Research

Background:

• Estimating marine larval abundance is challenging, limiting understanding of how adult diversity is maintained.
• Adult coral reef fish communities exhibit marked unevenness and reduced functional diversity compared to larvae.

Purpose of the Study:

• To investigate factors shaping marine fish diversity across different life stages.
• To determine the relationship between larval supply and adult community structure and diversity.

Main Methods:

• Surveyed adult coral reef fishes and compiled ecological/life history traits.
• Utilized a unique dataset of species-level larval abundances.
• Compared larval and adult community evenness and functional diversity.

Main Results:

• Larval communities showed more even abundance distributions than adults.
• Adult community structure was shaped by species filtering effects.
• Larval supply influenced adult diversity, but species size and diet modified this relationship, with larger/non-planktivorous species less abundant than expected.

Conclusions:

• Larval supply is a key driver of adult taxonomic and functional diversity.
• Post-larval processes, such as species filtering, increase numerical dominance and reduce overall adult diversity.
• Understanding life-stage dynamics is crucial for marine biodiversity conservation.