Meeting Abstract
Chelonibia testudinaria is an epibiotic acorn barnacle that attaches to sea turtles, manatees, and crabs. Much is unknown about the mechanisms by which this epibiont finds a host during the planktonic larval stage. This study identified the salinity tolerance of C. testudinaria larvae in order to understand in what water masses they are likely to occur and be able to settle on a host. Egg masses were collected from adult barnacles growing on horseshoe crabs and sea turtles. Larvae were reared in filtered seawater at 20 or 30 ppt salinity until they reached the cyprid stage and then groups of cyprids from the same cohort were transferred into beakers with salinities at 10, 15, 20, 25, and 30 ppt respectively. After 72 hours all cyprids were counted and classified as alive, settled, metamorphosed, or dead. Percent mortality and percent settlement were calculated based on total larvae per beaker. Mortality ranged from 2-100% and settlement ranged from 0-89%. Mortality was significantly reduced in the 10 ppt salinity treatment (P < 0.01). Settlement (i.e., the sum of both settled and metamorphosed larvae) was significantly reduced in the 10 ppt salinity treatment (P < 0.01) but had greater variability between trials than mortality rates.
