What is the waste product of a Bay oyster?

Welcome to the latest installment of the BayBlog Question of the Week! Each week, we take a question submitted on the Chesapeake Bay Program website or a frequently asked question and answer it here for all to read.

This week’s question comes from Lillian: “What is the waste product of a Bay oyster? Is it toxic and is there a use for this product?”

This question ended up being a little bit complex because there are several different interpretations of what the “waste” of an oyster is. Are you referring to the waste left from their filtering of the Bay’s water? The solid waste they expel? Or the waste shells left from human consumption of oysters? So we addressed all of these facets of the question for Lillian.

When oysters feed on algae -- filtering the water in the Bay at the same time -- some waste is left behind. Oysters take in water, filter out what they need for nourishment and expel the rest back into the water. This waste is often consumed by other organisms. In this way, oysters truly do provide for many of the Bay's other creatures.

Oysters also expel solid waste in the form of pellets, which decompose into the atmosphere as nitrogen. This type of nitrogen is not harmful to the Bay like the nitrogen that comes from fertilizer, animal manure, wastewater, cars and other sources that pollute the Bay.

The oyster waste caused by human consumption is perhaps the most useful, if proper procedures are followed. Instead of just tossing your oyster shells at the end of the night, they can be collected and used to rebuild the Bay's oyster population by providing habitat for oyster spat. This process, known as oyster shell recycling, is valuable to the Bay ecosystem because it gives spat a hard surface to grow on.

The Oyster Recovery Partnership has information on its website about how to get involved in its oyster shell recycling program. The Marylanders Grow Oysters program is another great way to get involved with oyster restoration if you live on one of the waterways that are part of the program.

Do you have a question about the Chesapeake Bay? Ask us and we might choose your question for the next Question of the Week! You can also ask us a question via Twitter by sending a reply to @chesbayprogram! Be sure to follow us there for all the latest in Bay news and events.