Temporal constraints on predation risk assessment in a changing world

Area of Science:

• Marine Biology
• Ecology
• Environmental Science

Background:

• Habitat degradation is a major threat to global biodiversity.
• Ocean acidification (OA) and ultraviolet radiation (UVR) are increasing environmental stressors.
• Limited knowledge exists on the temporal dynamics of chemical risk cues in aquatic ecosystems.

Purpose of the Study:

• To investigate how OA and UVR affect the degradation rate of chemical alarm cues.
• To understand the temporal aspects of risk assessment in coral reef damselfish.
• To assess the implications of changing environmental conditions on trait-mediated indirect interactions.

Main Methods:

• Experiments were conducted on alarm cues from ambon damselfish (Pomacentrus amboinensis).
• Cue degradation was measured under varying levels of CO2 (ambient vs. elevated) and UVR (present vs. absent).
• Time taken for cue degradation was recorded under different experimental conditions.

Main Results:

• Under ambient CO2, alarm cues persisted over 30 min without UVR.
• Elevated CO2 (~905 μatm) degraded cues within 15 min, even without UVR.
• UV radiation alone degraded cues within 15 min.
• Combined elevated CO2 and UVR degraded cues within 5 min.

Conclusions:

• Alarm cues degrade rapidly under natural conditions, especially with anthropogenic stressors.
• Elevated CO2 and UVR significantly accelerate cue degradation.
• This rapid degradation has profound implications for predator-prey dynamics and ecological interactions in coral reefs.