Brown Sea Nettle Jellies have gas!
Description and Comments
Just off of Coal Oil Point on the Goleta coast in Southern California we have a series of natural 'Seeps' that emit tar and methane gas which causes some areas to look like a bubbling hot tub and others to have a natural oily sheen on them. We observed over 50 brown Sea nettle Jellyfish looking like flat fried eggs on the surface. The methane gas bubbles rising get trapped in the Jellie's bell causing the jelly to "pinned" to the surface in the oil slick. This has been observed in this area quite regularly over the years with a variety of Jelly species and Salps seeming to succumb to the natural gas. The image shows one such Jelly with its bell full of gas amongst the oily surface.