Macro- and microplastics affect cold-water corals growth, feeding and behaviour

Area of Science:

• Marine Biology
• Environmental Science
• Ecology

Background:

• Ocean plastic contamination is a critical global environmental issue.
• Deep-sea ecosystems, particularly cold-water coral reefs, are understudied regarding plastic impacts.
• Lophelia pertusa is a key reef-building species in deep-sea environments.

Purpose of the Study:

• To investigate the effects of microplastics and macroplastics on the growth, feeding, and behavior of Lophelia pertusa.
• To assess the threat posed by plastic debris to cold-water coral reef health and resilience.

Main Methods:

• Laboratory experiments exposing Lophelia pertusa to microplastic and macroplastic debris.
• Monitoring of skeletal growth rates, polyp activity, and prey capture efficiency.
• Comparison of results with control and in situ conditions.

Main Results:

• Both microplastics and macroplastics significantly reduced coral skeletal growth rates.
• Macroplastics increased polyp activity but decreased prey capture, acting as feeding barriers.
• Microplastics reduced calcification without affecting polyp behavior or prey capture.

Conclusions:

• Plastic debris poses a significant threat to cold-water coral reef aggradation by inhibiting coral growth.
• Reduced coral growth and feeding efficiency jeopardize reef resilience and associated biodiversity.
• Further research is needed to understand the precise mechanisms of microplastic impact on coral physiology.