Biological and Physical Factors Affecting Southern Oyster Drill Abundance
About the Project
Southern oyster drills have been a devastating predator for oysters within the Gulf of Mexico. This predator is known for causing higher amounts of oyster loss during periods of high salinity. One aspect of southern oyster drill ecology that is unknown is the existence of sediment preference and if they congregate near areas with higher concentrations of oysters. This study will investigate southern oyster drill densities at several sites located along Mississippi and Alabama.
project overview
Half of the sites are characterized by coarse sediment (sand) and the other half have fine sediment (clay/silt). To investigate how concentrations of oysters may impact densities of southern oyster drills, half of the sites are located at oyster farms.
On these farms drill cages are placed at increasing distances away from the farm. Drill cages are constructed of pvc coated wire ½ meshing shaped into a rectangular prism. Cages have rubber strips leading up the sides to the opening at the top where drills enter the cage.
Initial Research
Oyster drill trap constructed of PVC coated chicken wire 1/2in mesh size formed into a 30X30X10cm rectangular prism with a 24X24cm hole along the top edge (A). One rubber strip stretches vertically up each side to allow drill access to the trap entrance (B). Traps are currently being built.
Example of trap deployment on a site with oysters. Traps deployed at edge, 100, and 200m away.
Map of study area along Mississippi and Alabama coastline depicting fine sediment sites (Deer Island and Bayou Sullivan) in yellow, fine controls in blue, coarse sediment sites (Ft. Morgan and Point aux Pins) in green, and coarse control sites in purple. Controls were selected by meeting specified sediment criteria, absence of oyster congregation near by, and salinity consistent to other sites.
Get in Touch
Cynthia Lupton, Extension Program Assistant
