Ft. Johnson

Located on Charleston Harbor, SC, Ft. Johnson provides an excellent area to survey marine invertebrates, as there are numerous habitat types that can be found surrounding the area, notably oyster bars/hard substrate habitats, mudflats, and salt marshes. Each habitat has it's own unique set of resident invertebrate species, and we have attempted to document and analyze changes in species compositions within each of these habitats.During the early 1970's (July 1972 and June 1973), marine biology classes from Grice Marine Lab did surveys of these habitats around Ft. Johnson and documented their findings in the Grice Log Book. These entries can be read in the Historical Survey file found below. Organisms were collected by hand, dip net, 20 foot seine, rotenone, and shovels, and then identified to lowest possible taxonomic group.

Recent surveys were done in March/April 2011 (hard substrate/oyster bar, saltmarsh), and February/March 2012 (mudflat, saltmarsh) by the GPMB Invertebrate Zoology class. Organisms were collected by hand, dip net, 20 foot seine, and shovels, and again identified to lowest possible taxonomic group.

As our ultimate goal was to document the change in community composition in each habitat over the past 40 years, we took care to sample the same areas and used the same methods documented in the Grice Log Book entries. However, there were inherent differences in the surveys that could not be avoided, such as time of year and the size of the group performing the survey. While historical surveys were done during the summer by an unspecified number of students in a Marine Biology class, recent surveys were done in late winter/early spring by groups of 2-7 people. Thus, caution should be taken when interpreting differences between the two surveys. 

The specimen identification, data analysis, and website pages for the Fort Johnson study were compiled by Anna Tommerdahl and Laura Mudge.