A research study submitted in partial fulfillment of the requirements for the degree of Master in Marine Plastics Abatement

Research studies project report (M.) - Asian Institute of Technology, 2021

The driving force behind microplastics consumption by marine invertebrates is still uncertain and impacts of such feeding behavior are barely fathomed. Although there are multiple researches on marine species and associated health effects from microplastics, research on marine invertebrates such as corals are still scant. This study tries to understand the feeding behavior of two species of corals on microplastics in presence of natural prey, Artemia nauplii. The research was carried out on Galaxea Fascicularis and Dipsastraea speciosa of Koh Ran Dok Mai (N13° 9'5.89" E100°50'3.53"). Corals were acclimatized and starved for 72 hours. After complete 72 hours, corals were fed three different types of microplastics ranged between 500-2000æm along with Artemia nauplii for three hours. This experiment found that coral polyps with long tentacles become active immediately as it comes in contact with microplastics, giving a higher probability for them to ingest microplastics. Experimental feeding trials revealed that corals can ingest at least 3% of microplastics provided during the experiment within 3 hours. Ingested microplastics were also reported to be egested mostly, however around 10% of the total ingested particles were retained within the coral tissues. Such act of retention can lead to potential health impacts in corals. This study suggests some corals are more at risk compared to other in terms of ingesting microplastics.