Protocol: ImageJ for Oyster Shell Parasites

Few studies have investigated how abiotic, biotic, and genetic conditions combined impact range-wide infestation rates of parasites on wild eastern oysters. I aim to map these spatial patterns of parasite infestation across the seascape and determine whether patterns correlate with environmental factors (temperature, salinity, co-occurring parasitic infestations) and/or population genetics. To achieve this, I am mapping the prevalence of parasitic Polydora worm blisters in eastern oyster shells.

​I've co-authored a lab protocol for using ImageJ to extract parasitic worm blister data with Lotterhos Lab summer intern Lisa Gouralnik! This protocol provides guidelines for identifying polydora worm blisters, using ImageJ to calculate total shell areas and areas of blister infection, and creating high-quality composite images. 

The Polydora worm burrows into oyster shells, creating irritation and weakening shell integrity. Infected oysters exhibit a lower condition index, a measure of health, than uninfected oysters.

Eastern oyster shells from the coastal Atlantic and Gulf of Mexico show parasitic worm blisters, outlined in dashed lines.

Above: Lisa in the shell imaging lab at the Marine Science Center. Right: Excerpt from the protocol about collecting data on complex colored blisters.

Lisa collected >2000 data points on the polydora worm blisters over the past two months of their internship. It was great to mentor them on this project, and I'm excited to get to the next steps of data analysis!