The Eastern Oyster (Crassostrea virginica)
Population Dynamics and Restoration
Rachel E. Willis | Wake Technical Community College
Summary
There are many aspects to understanding and
responsibly managing North Carolina’s natural
resources and estuarine ecosystems. Dr. David
Eggleston’s laboratory group at North Carolina
State University’s Center for Marine Sciences
and Technology is involved in a variety of
research projects regarding Eastern oyster
(Crassostrea virginica) population dynamics
and restoration in Pamlico Sound and
surrounding areas. Some of this research
includes quantifying oyster density, assessing
water quality, determining oyster filtration rates,
and tracking oyster larval settlement. Oysters
provide many ecosystem services and play an
important role in maintaining the health of these
ecosystems. They provide habitat for a variety
of species and protect shorelines and marshes
from erosion. They are involved in nutrient
cycling and are responsible for removing some
inorganic pollutants. Historical evidence reveals
a substantial decline in the oyster population of
North Carolina- this decline has diminished the
capacity for oysters to adequately filter local
waters.
Project Overview
Tank Demo
• Our goal is to determine oyster filtration rates and
establish how a decline in the oyster population is
affecting North Carolina’s estuarine ecosystems.
• To demonstrate the Eastern Oyster’s filtration
capabilities we set up a tank demonstration with
varying oyster densities.
Hypothesis
 Through determining oyster filtrations rates and
completing the tank demonstration, we expect to
see the most substantial water quality
improvements in the tank with the highest
density of oysters.
Methods
Data / Observations
• We used three 10 gallon tanks, each filled with 7.5
gallons of unfiltered Bogue Sound seawater.
• At the end of the 600 minutes, the water quality had
noticeably improved in the tanks containing oysters.
• All three tanks were oxygenated with air stones.
• The tank containing 40 oysters showed the greatest
improvement.
• There were two different treatment groups: 1) low
density, containing 10 oysters and 2) high density,
containing 40 oysters and a control containing no
oysters.
• To each tank we added 15mL of InstantAlgae
concentrated shellfish diet and stirred for even
distribution.
• Light conditions were kept constant and photos were
taken every 5 minutes for 600 minutes.
Conclusion
• These results reveal the impact of oyster filtration
capabilities, the importance of a healthy oyster
population, and the influence it has on maintaining
water filtration and water quality.
• This research can help us to understand the Eastern
Oyster’s role in maintaining healthy estuarine
ecosystems, as well as provide insight on how to
enhance and utilize the ecosystem services of the
Easter Oyster through conservation and restoration.