Restoring Serpulid Reef Habitat in Baffin Bay

There is nothing more iconic to the Baffin Bay ecosystem than its unique “rocks”. These ancient living structures, built over thousands of years by tiny tube-building Serpulid worms, provide key habitat that supports vibrant recreational fishing. Although living Serpulid worms continue to inhabit these reefs, this sensitive habitat is degrading in both size and distribution throughout the ecosystem, likely due to wave action and increased boat traffic. It is critically important to identify successful solutions to conserve remaining habitat and restore lost ecosystem benefits.

Baffin Bay is well known for its large and abundant Speckled Trout, Red Drum, and Flounder, and for being the top producer of Black Drum in Texas. Although prey resources for fish are often scarce in the bay’s mud-bottom habitat, particularly during periods of hypersalinity, Serpulid reefs host incredibly productive invertebrate (prey resource) communities, with densities 150 times higher than the surrounding bay bottom, perhaps holding the key to fisheries success. Baseline dietary analysis indicates that these reef-resident organisms play a large role in the diet of Black Drum. Although we do not yet have a comprehensive understanding of the ecological role of Serpulid reefs in Baffin Bay, a current study funded by the Coastal Conservation Association is helping to determine how reef communities are influenced by changes in water quality and how this may affect important fisheries species.

Serpulid reefs are very rare worldwide and along the US Gulf coast, are only found in Baffin Bay. Despite what we have learned and are still learning about the value of this unique habitat, a simple fact has not been addressed: Serpulid reefs in Baffin Bay have degraded compared to historic levels, with many areas already reduced to rubble. We propose to evaluate the efficacy of using alternative substrates for restoration of Serpulid reef habitats in Baffin Bay. Specifically, we will:

1. Compare the colonization of Serpulid worms on restoration substrates with those on natural Serpulid reef habitat,
2. Compare the colonization of restoration substrates by mobile and sessile invertebrate species (prey resources) with those found on natural Serpulid reef habitat,
3. Calculate and compare benefit-cost ratios for each substrate type to guide future restoration planning.

We have successfully conducted numerous restoration projects in Texas targeting oysters as the primary reef builder, including studies using alternative substrates to restore habitat and reef-resident organisms. Identifying substrates that fulfill similar ecosystem functions to natural Serpulid worm reefs will provide conservation benefits to remaining reefs and is critical toward future restoration of this unique habitat.