Settlement of the Acorn Barnacle Balanus From Mobile Bay and Weeks Bay, Alabama

Barnacle cyprids and metamorphosed settlers were collected using glass slides as artificial substrates at six sites in the Mobile Bay area. Three sites were located in Weeks Bay, Alabama, where the highest settlement concentration occurred near the entrance to Mobile Bay. Two sites in the north end of Weeks Bay near the Fish River had very reduced settlement. The remaining three locations were on the north shore of Dauphin Island, Alabama. Settlement at Dauphin Island was most abundant at the deeper of two sites at the Dauphin Island Sea Lab boat dock, possibly because the substrates were exposed to less wave action. The other two sites at Dauphin Island were shallow and relatively unsettled when compared with the deep site. Adult barnacles recovered from the Weeks Bay and Dauphin Island locations include Balanus eburneus, B. venustus, B. improvisus, and B. subalbidus. Our data indicate two primary settlement periods for these species, late winter to spring and late summer to fall, with the highest settlement occurring in Feb. and March