Eastern OysterCrassostrea virginica

Oyster Life Cycle• Pediveliger• 2 weeks old• Has a foot

• Spat• About 1 year• Spat prefer to settle on oyster shell

• Grow about 1 inch per year

• Females will only release their eggs when there is a reproducing male around and the water temperature is above 72.

Oyster HistoryOyster populations are at less than 2% of their historical levels.

Oyster History• Captain John Smith wrote about oyster reefs were so large and

plentiful that they were navigational hazards.

• Captain Smith also talked about oysters being as large as dinner plates.

What happened to all of the oysters?• Overharvesting• Disease• Poor water quality

Overharvesting• Before 1910, oysters were harvested with oyster tongs. Using

oyster tongs was not very harmful to oyster populations because it was very labor intensive. Plus, the tongs could only go but so deep.

Overharvesting• After 1910, the oyster dredge was introduced and the decline

of the oyster was accelerated. Watermen could catch a lot more oysters and destroyed the oyster reefs in the process.

Overharvesting• Shell was used for

roads, chicken feed or soil additive• Shell was not put

back on the reefs

Disease• Dermo and MSX took a toll on an already weakened oyster

population.

Poor water quality• Poor water clarity means no algae which means no food.• Lots of pollution means that the oysters are eating the

pollutants.

Why are oysters important?• Oysters are important because they can help reduce the levels

of the four major pollutants: nutrient, sediment, toxic and bacterial. They do this as they filter out their food.

• Oyster reefs provide habitat for many other organisms. Without oyster reefs, many animals would not live in an area. This makes oysters a keystone species.

Why we need to restore oyster reefs?