Predicting New Biofouling of Oyster Farms in Cape Cod Bay: Reproduction, Settlement, Temperature Dependency, and Modeling of Larval Transport

Lead PI: Jesús Pineda, Woods Hole Oceanographic Institution

Objectives

1. Implement circulation and larval dispersal models.
2. Use model output to identify areas and times of high biofouling. Test whether increased Chthamalus larval supply in Buzzards Bay serves as a source for populations in Cape Cod Bay (CCB).
3. Use settlement data to test model predictions of biofouling.
4. Resolve if East CCB shore environments offer Chthamalus a refuge from Semibalanus competition.
5. Resolve experimentally whether differences in biofouling growth on gear depend on temperature mediated by gear color.
6. Model substrate temperature across CCB and on gear of different colors to predict competitive outcome between barnacle species.

Methodology
We will implement a high-resolution circulation/dispersal model, which includes flow through the Cape Cod Canal, that will be parameterized for C. fragilis and S. balanoides barnacle larvae and informed by field measurements of reproduction and settlement. Substrate temperatures, including oyster-farm gear, will also be modeled to predict competitive outcome between the two species and to predict abundance and regional distribution of C. fragilis. We will also collect field observations of settlement and temperature, to characterize these variables and to test the model, and we will conduct biofouling growth experiments on dark and light oyster-farm gear.

Rationale
Biofouling causes loss in productivity to Massachusetts oyster farms. We propose work to predict new biofouling on Cape Cod Bay oyster farms, possibly already underway, in response to ocean warming. Our research aims at a mechanistic understanding and prediction of this new biofouling by a semitropical barnacle. The project aims at disentangling the larval dispersal processes (spawning, larval transport and mortality and settlement), and the biological interactions (competition mediated by temperature with a northern barnacle) that are currently slowing the spread of a barnacle biofoluer to Cape Cod Bay waters and north.