About This Project

Coral reefs provide important cultural, economic and ecologic resources. These important ecosystems are increasingly threatened by plastic pollution. Although we know that corals eat plastics, there have been very few studies conducted. I will be conducting the first and largest analysis of the physical and chemical properties of coral ingested microplastics within the Main Hawaiian Islands, Papahānaumokuākea and American Sāmoa.

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What is the context of this research?

Corals receive most of their nutrients from photosynthesis, but their remaining nutritional needs can be met by feeding on small organisms and particles in the ocean. Laboratory studies have already shown that eating microplastics can lead to coral bleaching, reduced growth rates, and compromised immune system responses with implications for the survival of corals. The effects seen were due to the physical characteristics of microplastics raising questions about the chemical characteristics. We urgently need to establish a baseline for current conditions of microplastic pollution within corals so that further laboratory investigation can be conducted using environmentally relevant concentrations, types of microplastics, and their chemical compositions.

What is the significance of this project?

This project will be the largest coral ingestion of microplastics study in the world and the first large-scale survey of its type in the Pacific. This is also the first survey which will directly measure the chemical contaminants within ingested plastics. This research reveals coral preferences, plastic retention, and microplastic chemical risks, vital for ecosystem protection. The absence of documented microplastic ingestion by US Pacific corals, amid ocean acidification and warming, emphasizes the urgency to understand these hazards. Filling this data gap is critical for actionable science to combat microplastic pollution in the Pacific Ocean.

What are the goals of the project?

This project will assess if corals are preferentially eating certain types of microplastics and how this differs based on proximity to human populations (uninhabited vs. inhabited) and sources of marine debris (local vs. distant) by collecting samples from across American Samoa, Papahānaumokuākea and the main Hawaiian Islands. Additionally, quantify retention of microplastics and determine if polyp size (small vs. large) or skeletal structure (imperforate vs. perforate) affects which types of microplastics are retained by collecting five coral genera (Porites, Pocillopora, Montipora, Leptastrea, and Lobactis). Lastly, determine the chemical composition (additives and sorbed chemicals) of ingested microplastics to identify the types of chemical contaminants corals are encountering