There is no realm within the vast assemblage of marine plankton that we have studied in greater detail and depth than the group that we call the ‘Blues Brothers’.
This is a community of ever drifting surface-hugging blue and purple creatures of extraordinary beauty and mystery, and one which periodically drifts on westerly gale force winds and currents from the mighty Gulf Stream, to end up stranded on our most westerly shores, particularly the beaches of Cornwall.
Though much more refined than Janthina when devouring prey, Glaucus, the Blue Sea Slug takes no prisoners when it encounters Velella, Porpita and Portuguese Men-O-War, or the sargassum anemone. Glaucus eats them all, and uses for its own protection the stinging cells of their prey. They simply move the stinging cells to their finger tips, where they can fire them in anger…
Porpita resides on the underside of the ocean’s surface, whereas Velella sits on top, with tentacles tipped below. Porpita sweeps its tentacles vertically down periodically. Porpita is a Chondrophoran, a modified single Hydroid polyp. The team are arguably some of the first to recognise multiple colour morphs.
The Blue Sea Slug, Glaucus, feeds avidly upon Porpita, as well as other members of the Blues Brothers Group.
A full grown Physalia colony can have a float 250mm long and around ten tentacles that extend to thirty or forty metres, packed with powerful and dangerous stinging cells along the entire length.
Blind and incapable of swimming, Janthina. The Purple Bubble Raft Snail, has to rely on wind and wave driving it to within a few millimetres of its Velella prey before it can effect capture and enjoy a meal.
There are thousands of stories that can be told about the complex network of relationships that occur between the ‘blues brothers’ – to name a few: Janthina eat Glaucus – Glaucus eat Physalia, Vellela and Porpita. Janthina also feed on Porpita, Vellela and Physalia. Physalia, Vellela and Porpita all feed on plankton and small fish. These various stories we intend to tell physically and digitally, through our venues around the world.
