A combination of rising sea levels and predation of marsh plants by resident ponies make’s Chincoteague Island’s shoreline particularly vulnerable to climate change and natural disasters such as Hurricane Sandy. This made it a prime candidate for the Nature Conservancy’s oyster caster restoration program. This program creates “castles” out of formed cinder-blocks which simultaneously protects the shorelines by creating a barrier to wave action and creates some sweet digs for our bivalve friends. Now that’s what I call a win, win!
Thankfully I was there to help build these palaces, and relay all the valuable info that I learned to you dedicated educators who may be interested in taking on an ambitious oyster castle project of your own. Now to be honest when volunteering to help with this project I assumed that, it would be a lovely day out on the water, ending in a feeling of accomplishment. However, it ended up being a rainy day, with water filled waders and sore arms from hauling cinder-blocks all day. Yet, the feeling of accomplishment was the same as I had expected. So needless to say it is quite the undertaking and would not recommend attempting it with a younger crowd.
So here is some oyster castle science to help you teach about or build your own oyster castle. Oysters spawn in the summer months when the water starts to get warm, and spend only the first couple weeks of their lives as free moving organisms before they find a hard surface to attach to for life. So that is why it is important to get oyster castles out in the spring to give the baby oysters something to attach to once spawning occurs. Oysters tend to like to form reefs, and typically prefer to attach to other oyster shell if it is available. However natural reefs which provide protection from sedimentation and a source of Calcium Carbonate (the substance oysters use to build their shells) are scarce, so oyster castles are made of 30% oyster shell and provide the vertical elevation that the oysters need to keep from sinking into the sediment. Oyster castles jump start the reef building process by providing a good habitat for a first generation of oyster to thrive which in turn create a surface for the future generation of oysters to grow once they die.
Hopefully you have been inspired, to build your own oyster castles or teach about oysters as a way to protect shorelines. For more info and lesson plans on oysters check out our other resources available on bay backpack, and for more info on oyster castles and how to get your own check out Allied Concrete.