Sneak Peek into Our Oyster Restoration Project

Charlene Trippeda, Conservation Intern (Fall 2023)

This fall I decided to take on the oyster restoration project that BHIC has been conducting for the past few years. I teamed up with Jonathan, another conservation intern, and we decided to add RTK GPS mapping to the project. Our project consists of two parts: looking to see if restoration efforts have been effective, as well as scouting for a fourth restoration site and using an RTK GPS to accurately measure the reef’s elevation and area. We will also be using the RTK GPS to map a potential new restoration site.

One of our wild reef sites.

One of our restored reef sites.

We have four restoration sites that are each divided into three sections of reef: a wild reef, a restored reef, and a control area. The restored sites use mesh bags of recycled oyster shells to provide a place for new oyster recruitment, wild sites are natural growing oyster reefs, and control sites are used as a baseline to see what grows and lives on the edge of the salt marsh. We collected samples from each of the sites to look for productive oyster growth and surveyed other organisms living in the reef.

Jonathan and I at one of the control sites, which mostly consist of mud snails. We’re using a ⅓ x ⅓ meter quadrat. We used this as a place marker so we can dig out our samples within the square. We dug about 6 inches down for each quadrat.

At one of our wild reef sites, using the quadrat to sample again.

We measured oyster reef length and width to see if the size of the restored and natural reefs have changed over time. While on the reefs, we collected water quality and water depth measurements and looked at percent coverage of oyster reefs. Lastly, we collected three sets of oyster samples from each site and brought them back to the lab to sort through. Our goal was to count and measure the length of live oysters while also seeing how many were dead and/or had spat recruitment.

For the second part of our project, we will be using the RTK GPS to get an accurate representation of the size, shape and elevation of the reefs.

Jonathan and I getting ready to head to our first site to collect samples. We had one other person help us with the field portion of our project. In order to get to our sites we had to each take a tandem kayak and fill it with all of our needed supplies.

We had a lot of help when we brought our samples back to the lab. We recruited both staff and interns to help us wash and sort through our samples.

An RTK GPS is a great tool because it takes accurate measurements that are only a few centimeters off. This will be helpful because we can use the RTK to get accurate coordinates to map the entire area of the reef. Not only that, but we can also use the RTK to find the elevation gain or decline of a reef. When future interns go out to re-measure the area, they can see if marsh accretion or erosion occurred, which can help us determine the productivity of the reefs