cr: Drawnbydawn
Oysters are a bivalve species which feed mainly on small particles such as phytoplankton and algae. They feed themselves by pumping large amounts of water and all sorts of particles in their bodies. The water then enters the gills where its small halls called ‘cilia’ will transport these particles down the system. Rejected particles are trapped in the mucus and are bound together called “pseudo-faeces”. The food particles are then transported to the stomach and esophagus (May, C., 2017)
One adult oyster is able to filter up to 50 gallons of water per day and this contributes to water clarity. They do this either by eating pollutants or shaping them into small packets of deposits, discharging them to the bottom of the ocean where they are harmless.
cr: ravenlady
Video of water filtering (cr: oysterrecovery)
Picture of water in Chesepeake Bay (cr: bibleworldadventures)
The once-flourishing oyster population at Chesepeake Bay was able to filter excess nutrients from its estuary of water every 3 to 4 days.
Without water filtering, excess nutrients in the water can result in eutrophication – excess growth of plants/ algae. The blooming of algae would block sunlight from getting into water, creating a hypoxic zone where no organisms can survive.
A case of eutrophication (cr: sailingtunas)