Lifestyles for Better Living

Sea Nettles

Chrysaora fuscescens, more often known as the Pacific or West Coast Jellyfish and Chrysaora quinquecirrha, known as the Atlantic or East Coast jellyfish are a free floating species of jellyfish found, respectively, in the Pacific Ocean and Atlantic estuaries. The Pacific is the larger of the two jellyfish, ranging in size from six inches to three feet in diameter and is normally a golden brown colour with tinges of red. Its smaller cousin, the Atlantic jellyfish generally grow up to foot in diameter and are pink or yellow with deeply coloured striations. On both species the tentacles are usually at least twice the length of the body.

Feeding habits for both species are largely the same, both being carnivorous. They feed on plankton, small crustaceans, small fish, eggs, larva and worms. Although both are excellent swimmers they cannot hunt their own prey; instead their tentacles are spread, net-like, over as large an area as possible, thereby trapping any food that comes within range. Like almost all jellyfish species, the tentacles contain a toxin that is used to paralyse the prey before it is passed up to the mouth and into the stomach of the jellyfish.

The breeding cycle for the Sea Nettle is identical for both the fuscescens and the quinquecirrha species. The male releases sperm into the water. The female than takes the water in and pushes it around her body to fertilise the eggs. Once the eggs have hatched into larvae they are thrust into the water to make their own way. For a female jellyfish, there is no such thing as parenting. The only role the female plays is to hatch the eggs; her job is then done. Once the larvae are released they are carried along on the current and many will not survive. Those that do survive eventually find their way down to the bottom and seek out a hard, flat surface upon which to attach themselves. At this stage they are at their most vulnerable.

However, the young, now known as polyps have a defence mechanism. They can ball themselves up against danger and harsh conditions and, in this way can wait until the time is right for hatching. This stage can last up to a few years if the conditions are not right for development. Once the spring arrives and the temperature increase, the polyps now start to is means that they are able, without the use of sperm or eggs, able to create a copy of themselves. The new polyp is released into the ocean when it is fully developed and it is these that go on to become full grown Sea Nettles.

The venom of both the Pacific and the Atlantic Sea Nettle is mildly toxic to humans. Whereas this toxin will completely paralyse any small fish or creature that comes into contact with it, on a human being it is no more than a painful, irritating rash, not lethal unless a severe allergic reaction is experienced. Even then, with prompt medical attention, death is highly unlikely. It is possible to ease the irritation of a sting by lightly spraying vinegar over the site. As with any jellyfish sting, it is not advisable to rub or scratch the area as this will facilitate quicker circulation of the poison.

In the wild the lifespan of the Chrysaora fuscescens and the Chrysaora quinquecirrha is approximately six to twelve months. However, they can be kept in captivity and their lifespan can be extended to between eighteen and thirty six months if they are cared for properly. Many aquariums house both of these species in their displays and they are well worth going to see if you get the chance.

For more information, pick up the Nook version of “Jellyfish As Pets“ at Barns and Noble.
You can also buy the PDF file from Paypal for $2.99

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