Sightings of siphonophores in Maltese waters

The Grand Siphonophore (Forskalia edwardsi), consisting of hundreds of polyps in each colonial structure, as in the Portuguese Man-of-war (Physalia physalis), are also being spotted in large numbers in Maltese waters.

The colonial structure in the Grand Siphonophore species is tapered, resembling a rope which may vary in length between one to 10 metres.

The upper part of the colony, which is very translucent, is composed of a small float and several sets of swimming bells.

Below, spread around the central stolon, are hundreds of salmon-coloured specialised and differentiated polyps, serving various purposes including nutrition, reproduction and protection.

It is a very stinging species encountered close to the sea surface, as may be seen in the photo taken during ongoing research by Adriana Vella, of the Conservation Biology Research Group of the University of Malta’s Department of Biology.

This large siphonophore lives in all oceans, including the Mediterranean, and is being recorded in large numbers around the Maltese Islands.

Other gelatinous creatures encountered included the Bioluminescent Comb Jelly (Beroe forskalii) and the Pelagic Tunicate or Salp (Salpa maxima), joining the well known Mauve Stinger Jellyfish (Pelagia noctiluca).

The data will be used in a collaborative Mediterranean-wide research project co-ordinated by the Mediterranean Science Commission (CIESM).

To forward reports of any sightings of gelatinous creatures or for any further information e-mail the national contact person (Dr Vella) at JellywatchMalta@gmail.com.