No. 34–Oyster Project, Part II

In the spring of 2003 I was one of many volunteers enlisted by SCDNR to build three artificial oyster seed reefs landward of the boardwalk adjacent to The Sands boat landing in Port Royal. Over the ensuing months I made regular visits to the site to observe the progress of the endeavor.

One thing I noticed early on was the amount of siltation occurring on one reef in particular and the other two to a lesser extent. Portions of the reefs where spat had attached during the spawn were being covered and the spat smothered. I spent some time surveying the entire area and making note of where and under what conditions oysters were growing naturally. From those observations came the idea that DNR’s reef construction method might be improved upon and that this provided on opportunity to partner with Port Royal Elementary to test that hypothesis.

Early in ’04 I approached Mrs. Keeler with that idea and she jumped on it, assigning then science lab teacher, Michael Morello, to the project. The purpose of the project was three-fold; to introduce the students to the scientific method, explore new and possibly more successful configurations for artificial oyster seed reefs and to study and hopefully mitigate marsh bank erosion.

The participants met together for the first time in for an orientation session during which the students learned about the oyster restoration project sponsored by SCDNR. The students were told that it would be their task to learn about oyster reproduction, life cycle and habitat and how environmental forces effect spat colonization and growth.

The first field study was conducted in April with each student being given a journal for recording their observations of how the DNR reefs were designed, oyster colonization patterns and growth on the reefs and surrounding environment, and factors that may be affecting colonization and survival. They also observed areas of marsh grass erosion and the accretion of sediments landward of the DNR reefs.

The last part of that session was at the Estuarium where the students were introduced to materials (approved by DNR) that could be used in the experiment. They were asked, based on what they had learned, to brainstorm reef configurations that could be used for experimental purposes.

Field observations lead to discussion of how to address reef silting problems. It was decided that placing the oyster bags on wooden pallets would allow for a washing effect below and that leaving space between the bags would provide more self cleaning vertical surfaces for spat attachment.

The students constructed their pallet test reef at The Sands in May along with a control reef mimicking the DNR design. The experiment took an unexpected turn in August when it was found that tropical storms damaged both reefs beyond repair. After the initial disappointment of seeing their previous labors strewn across the beach, the students rose to the challenge of learning from failure by recording observations to be used in redesigning the reefs to withstand storms.

Hardened test and control reefs with new elements designed to stand up to wave and tidal forces were constructed in May of ’05 and have been under observation by the students since. The original hypotheses regarding both reefs have been borne out to date with excellent colonization and growth on the pallet reef and the anticipated siltation problems on the control reef.

The students were surprised and honored this spring to learn that DNR would be installing test pallet reefs of their own. Unfortunately, circumstance led to those reefs not being constructed till very late in the spawning season. The students found minimal spat recruitment on them during August field observations.

Two new experimental elements for the project set out by the students this May had produced mixed results by July. In earlier observations of the general project area the students had found oysters growing on metal cable, wire, and fishing line hanging from the support structure of the boardwalk. The idea was an adaptation of the DNR’s use of commercial plastic bread trays in a way that had turned out not to work very well.

The DNR had filled trays with lose shell covered and contained by mesh. The student’s idea was to weave wire through the trays for the spat to attach to. With cost concerns in mind, two different gauges of wire were used on two separate trays. The lighter less expensive wire completely rusted away and while still intact, the heavier and also rusted wire had no spat. The big and exciting surprise was the large number of viable spat attached to the bread trays themselves.

Though this year’s experiment fell far short with regard to anticipated results, it has put young minds eagerly to work by following lessons learned into new avenues of inquiry. That is success by any measure.