5.1 Wednesday, Jan. 4 Benthic baby snatchers: predation on marine invertebrate embryos inside gelatinous egg masses VON DASSOW, Y.J.; Duke University, NC email@example.com
A common reproductive strategy for marine invertebrates involves the packaging of embryos into benthically-deposited egg structures. Some of these structures take the form of gelatinous masses with embryos embedded inside. The energetic costs of egg mass production suggest associated benefits, one of which may be protection of embryos from predation. Here, I examine two cases in which gelatinous masses fail to provide protection for embryos, and are in fact specifically targeted by predators. In one case, embryos of maldanid polychaetes are eaten directly out of the gel by the prosobranch gastropod Nassarius vibex. In the other case, the opisthobranch gastropod Olea hansineensis eats embryos of other sea slugs directly out of their masses. In both cases, individual embryos are consumed whole while the gel matrix is left largely intact, and the predators appear to prefer younger embryos. Surprisingly, neither predator eats embryos that have been removed from the egg mass. Thus, I hypothesize that chemical cues attracting the predators originate in both the gel and the embryos.