The only way to determine if a restoration project is working is to return to the site and collect samples. For oyster reefs, sampling requires advanced planning to identify points on the irregularly shaped reef that could be sampled, then selecting sites from a random number table.

“This random selection process for collecting samples eliminates observer bias, which may inadvertently select sites based on specific sections of the oyster reef,” explains SCCF Marine Lab Director Eric Milbrandt, Ph.D.

The constructed reefs that the Marine Lab visits every March include those that were restored in 2016, 2018, and 2025.

“In order to compare the restored reefs to naturally occurring reefs, we also collect samples from reference reefs,” says Milbrandt.

To sample the reefs, the scientists go to the randomly selected point with a handheld GPS and place a small quadrat (25 X 25 cm or 1/16 of a meter).

“We collect all living and dead oyster shells within the quadrat and place them into a bucket. Next, the samples are brought back to the lab and measured using digital calipers,” he says.

The calipers are connected wirelessly to the computer, and a spreadsheet logs the size of each oyster (in mm) and records the total number in each sample.

We compare oyster density (# per square meter) and size (shell height) in the restoration and reference sites.

“We’ve found that the restored reefs are statistically similar to the reference sites within two years of construction,” said Milbrandt.

Looking ahead, SCCF has several oyster restoration projects lined up with volunteers as well as large-scale projects in the coming years.

Learn more about our oyster restoration work>>>