Dermowatch detects disease hotspots in the Gulf of Mexico

DermoWatch (www.dermowatch.org) is a web-based community for the monitoring and management of the lethal oyster parasite, Perkinsus marinus (= Dermocystidium marinum). Oysters from the major oyster producing areas of the Gulf of Mexico are collected and assayed for P. marinus. The web site displays station information, water temperature and salinity, and percent infection and disease intensity (weighted incidence) of sub-market and market-sized oysters. Weighted incidence values of 2.0 and greater are highlighted as hotspots, where oysters (Crassostrea virginica) are likely experiencing serious disease-related mortality. Recent disease hotspots are found in Corpus Christi Bay, Aransas Bay, Matagorda Bay and Galveston Bay. Within a bay, hotspots are established on high-salinity reefs and proceed up-estuary. Between bays, hotspots tend to progress from south to north. Within and between bay patterns of progression and regression of disease hotspots are likely cyclical, and should provide a useful indicator of the trajectory of infection.