Meeting Abstract
Of the upwards of 150 ctenophore species, the oceanic ctenophore Eurhamphaea vexilligera is peculiar in its release of a pigmented and bioluminescent ink, secreted from numerous small vesicles that line its comb rows. To date, in situ observations by SCUBA divers have proved the most fruitful method of observing these animals’ natural behavior. We present the results of one such contemporary SCUBA-based observation of E. vexilligera, conducted in the Gulf Stream waters off the coast of Florida using high resolution photography and video. Utilizing underwater camera systems purpose-built for filming gelatinous zooplankton, we observed E. vexilligera ink release and swimming behavior in situ. From these data, we describe the timeline and mechanics E. vexilligera ink release in detail, as well as the animal’s different swimming behaviors and resulting ink dispersal patterns. Our footage also revealed a previously-undescribed rolling swimming behavior, accompanied and possibly facilitated by a characteristic change in overall body shape. These observations provide further insight into the behavioral ecology of this unique ctenophore and may serve as the foundation for future kinematic studies.
