Florida Conservation News, Blogs, and Updates

It is only appropriate that our first Species Spotlight is the Eastern oyster (Crassostrea virginica). We also like to call it the mighty oyster, you’ll find out why after reading this. The eastern oyster is often called an ecosystem engineer because of their ability to build reefs and support communities. Many organisms call oyster reefs home, this list includes: crabs, fish, snails, mangroves, and birds. These reefs also provide many key ecosystem services to coastal communities. 

When looking specifically at the oyster, it is important to know how they reproduce to build these reefs. An oyster becomes a mature adult after about one year. When the water temperature exceeds 68 degrees Fahrenheit, oysters will spawn and release their gametes into the water. Once the eggs are fertilized, the oyster larvae will be planktonic, floating through the water for the next two to three weeks. Then, the larvae will find hard substrates like other oysters, like the ones on our VOGs, to attach to. After settling onto this substrate, they are now called spat. The spat will grow and mature until they are able to reproduce and grow the reef.

In addition to their reef building capabilities, oysters can filter up to 50 gallons of water each day. Oysters are filter feeders, meaning that they will run water over their gills, removing any plankton, and spit out clean water. In this process, they also can remove any sediments or pollutants in the water. While an oyster can filter up to 50 gallons a day, there are some factors that can reduce this number. For example, if there is too much sediment in the water, it could actually clog up the oyster’s gills, slowing the filtration or even killing them. Also, if an oyster is stressed, usually from being exposed to the air, salinity changes, or from predation, the amount of water they filter could decrease. 

Our oysters also help protect our shorelines from wave energy. Their reef structures can help calm the water and slow down waves that might erode our shorelines. Part of why we deploy VOGs is to help stabilize our shorelines and slow down the water movement. 

The mighty oyster does more than build reefs—it supports biodiversity, improves water quality, and protects shorelines. By restoring our oyster reefs, including through the use of VOGs, we help ensure a more resilient future for our coasts. Stay tuned for more Species Spotlights and ways to get involved in our restoration efforts!

Sources:

Chesapeake Bay Program

Florida Fish and Wildlife Conservation Commission