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Newport’s Eelgrass and its Residents is back with the continuation of the family of mollusks living in Newport Bay. This time we explore Oysters and their remarkable potential to benefit eelgrass as much as eelgrass benefits them.

Oysters reach maturity in one year and they are hermaphrodites, meaning they change genders at some point in their lives. Oysters start out as males releasing sperm and as they develop over the next two or three years, they become females producing eggs.

As the eggs are fertilized they develop into larvae and zoom through the water searching for suitable places to grow, such as the outside of another oyster’s shell. Common predators of oysters include crabs, seabirds, starfish and of course, humans.

The native oysterOstrea lurida, can be found living within and adjacent to eelgrass meadows in southern California. Oysters are a foundation species, meaning that they play a large role in modifying their environment and a critical role in maintaining structure in the community.

A group of oysters forms a bed or reef because they themselves provide habitat for a number of marine species. The nooks and crannies in the oyster shells provide a place where other small organisms may live.

Oysters may drastically improve water quality. They filter large amounts of water by feeding and thus removing nutrients, sediments and other pollutants out of the water. Filtering up to 50 gallons of water per day, oysters may be able to improve the amount of light reaching nearby eelgrass.

Eelgrass requires between 18 and 30 percent of light available at the water’s surface to reach its leaves. Therefore, the depth in which eelgrass is able to grow is solely dependent on how much light can reach them. By filtering the water of its particles, oysters have the ability to make the water clearer and allow eelgrass to receive more sunlight. Oysters actually give back to their habitats!

Here’s a video highlighting how effectively oysters filter water!