Cyanea capillata, also known as hair jelly or lion’s mane jelly fish, is the largest species of jelly fish known today. These stunningly beautiful creatures are colorful and really large – the largest individuals seen measure 120 feet in length when the tentacles are fully extended.
They prefer cold water marine habitats, being common and widespread around the Arctic, in the North Sea, in the seas around Scandinavia and in the Irish Sea. They usually live in the shallow waters, floating and swimming around in waters not deeper than 20 m. They sometimes migrate over large distances – they propel themselves with slow, pulsating movements and they also use the water currents to make traveling easier for them.
Lion’s mane jelly fish are large, but only few of them reach the record length mentioned above. The individuals that live in the north usually have larger bodies than their counterparts inhabiting lower latitudes and their tentacles are also longer, usually reaching the length of 100 feet. Independent of their size, all lion’s mane jelly fishes have eight clusters of colorful tentacles, the bundles containing a huge number of individual arms, usually more than 100 each. The tentacles start from the center of the body called the bell that is divided into eight separate lobes. It is the bell that accommodates the animal’s only orifice as well – it is a double-purpose organ that serves as a mouth and as an anus as well.
Scientists have found that coloration is closely related to size. Larger individuals feature more vivid colors, crimson and deep purple being the two most common hues, while smaller animals are usually tan or orange.
Lion’s mane jelly fish are short-lived creatures, usually living only for one year, most of which they spend in the open seas, very rarely settling in bays. They prefer the company of other species such as shrimps and butterfish and they mingle with them for protection. They need all the protection they can get because they are the preferred treat of many other marine species such as leatherback turtles and birds. The lion’s mane itself feeds on small fish, other jelly fish such moon jellies, and plankton.
In terms of proliferation, these large creatures are very similar to other jelly fish species. They are able to reproduce sexually and asexually as well, the former being chosen when the animal is in the medusa stage, while the latter being the method chosen in the polyp stage. The fertilized eggs are carried by the female individual on her body, among her tentacles and are released only after they hatch into larvae. The mother then deposits the larvae on rocky surfaces where they become polyps. They start reproducing in this polyp stage, while still attached to the substrate and they also continue to grow there. They break free when they reach the following stage of development, the ephyra stage, after which they soon become fully developed hair jelly individuals.