Date of Award

Spring 1998

Document Type

Legacy Thesis

Degree Name

Bachelor of Science (BS)


Marine Science


College of Science

First Advisor

Richard F. Dame


Perkinsus marinus, the parasite responsible for dermo disease in oysters, has caused extensive mortalities of the eastern oyster Crassostrea virginica along the Gulf and Atlantic Coasts of North America. Numerous studies indicate that infection intensities vary widely within an estuary. Many of these studies correlate this variation to salinity, with P. marinus typically more abundant in higher salinities. This relationship is often attributed to an intolerance of low salinities, but recent laboratory studies indicate that the parasite can proliferate well at low salinities. We hypothesize that creek hydrography, including residence times and temperature regimes, are more of a spatial distribution determinant than salinity. This paper presents the spatial distribution of Perkinsus marinus along intertidal creeks in relation to tidal elevation and other spatial characteristics of the creeks. In early August, 1997 oysters were collected from discrete oyster reefs (n=10 oysters/reef) along the lengths of eight intertidal creeks in North Inlet Estuary, SC. Standard fluid thioglycollate tissue assays were performed for each oyster to determine Perkinsus marinus infection levels. Mackin scale ranked infection intensities were regressed.