Blue Crab Tagging in the Stono River
The specific migratory patterns of blue crabs are not very well known, and an opportunity exists in the fall of each year to tag large numbers of recently shed female crabs. At that time of year the market is weak for these crabs and they are generally plentiful (3 to 4 dozen per trap). It is also an interesting time of year to tag them, because they are beginning a migration towards the inlet to eventually sponge up and hatch eggs.
This project would take advantage of this traditionally slow time of year to tag crabs. Approximately 2000 crabs in the Stono River will be tagged and migration patterns followed during the course of my normal crabbing operations.
Tags will be ordered from Floytag thus being virtually identical to the tags DNR has now. They will be sequentially numbered and labeled with DNR's address. Once the tags arrive they will be prepared for application, with wire inserted through the holes and one end pre-bent for easy application. At this time a data sheet for carrying in the boat as well as a spread sheet for recording data will be designed.
Starting in Sept. 2007, 5 days will be budgeted for the application 2000 purchased tags and up to 400 tags currently available from DNR. Tagging will be completed before Dec. 1 2007. As soon as the first tags are deployed, a GPS unit will be purchased and installed on the boat. Any recaptures will be recorded and logged into a spread sheet, as well as any recaptures reported by people other than myself. All tagged crabs that are recaptured will be released and other crabbers will be encouraged to do the same. Data will be gathered until April 1, 2008 or until 4000 recaptures are recorded, whichever comes first. Upon completion of the study, a report will be written summarizing results.
This project will benefit any one who has an interest in crabs, because it will attempt to track a broodstock class, determining their migratory path and estimating their theoretical survival to sponge. The expected outcome is that they will follow the same path to the inlet that I follow when fishing for females in the fall, and as the females get caught up, tagged crabs will become a greater proportion of the total catch.