Access to Cleaning Services Alters Fish Physiology Under Parasite Infection and Ocean Acidification

Area of Science:

• Marine biology
• Ecology
• Physiology

Background:

• Cleaning symbioses are crucial mutualistic interactions in marine ecosystems.
• These interactions benefit client fish by removing ectoparasites, influencing fish diversity and abundance.
• Ocean acidification (OA) poses a threat to marine life, potentially impairing cleaner fish behavior.

Purpose of the Study:

• To investigate the impact of cleaning services on client fish aerobic metabolism under parasite infection and OA.
• To assess how long-term access to cleaning impacts damselfish (Pomacentrus amboinensis) physiological responses.
• To understand the combined effects of parasite infection and OA on fish with and without access to cleaners.

Main Methods:

• A long-term experiment involving the removal of cleaner wrasses (Labroides dimidiatus) from patch reefs.
• Experimental parasite infection and acclimation to high CO2 conditions (OA).
• Measurement of client fish aerobic metabolism, including maximum metabolic rate and aerobic scope.

Main Results:

• Damselfish with access to cleaning services exhibited a negative metabolic response to parasite infection.
• Fish without access to cleaning showed the lowest factorial aerobic scope after OA acclimation.
• Reduced access to cleaning services exacerbated the negative effects of OA on fish aerobic scope.

Conclusions:

• Access to cleaning services is vital for client fish to effectively manage metabolic stress from parasites.
• Ocean acidification negatively impacts fish aerobic scope, with more severe effects in fish lacking cleaning services.
• Reef fish may face trade-offs between parasite tolerance and resilience to other environmental stressors like OA, especially in degraded reef systems.