Jellyfishes
The many creatures on this page are lumped together for the one trait they all have in common - they are all "jelly-like" - soft, gelatinous, and more-or-less transparent. Other than that, they are for the most part completely unrelated. True Jellyfishes, Hydromedusae, and Siphonophores are in the phylum Cnidaria, related to bottom-dwelling Hydroids, Sea Anemones, and corals. Comb Jellies are in the phylum Ctenophora, and are completely unrelated to jellyfishes, as are Sea Butterflies and Corollas, which are mollusks. Salps are free-swimming tunicates, more closely related to us than to any of these other creatures.
Small harmless hydromedusae also appear sporadically in freshwater. There are also some types of freshwater jellyfish, but not around here. The rest of the ( non-cnidarian ) creatures on this page are unrelated, sharing only their drifting lifestyles.
Red Jelly Cyanea capillata (right)
Jellyfishes are free-swimming relatives of corals, anemones, and hydroids. In fact, in many cases, they are the same species, just in a different stage of life! Not all medusas ( as jellyfishes are called ) have a corresponding polyp stage, and likewise, not all polyps have a corresponding medusa stage, but most alternate generations in each form. Small jellies ( up to 1" across ) are most likely the medusa stage of some hydroid, while large jellies are usually the dominant stage of a species in which the polyp stage is almost absent. Even anemones have a periodic medusa stage, although it is infrequently observed.
Although jellyfish can swim slowly, they are largely at the mercy of the tides and currents, and at times large numbers are concentrated into bays and may be stranded on beaches.
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Although superficially similar to jellyfishes, hydromedusae are more closely related to sessile hydroids. They are much firmer and sturdier in body than jellyfishes. Most are small ( less than 1 inch in diameter ) and do not sting. Others, such as the large and very dangerous Sea Wasp ( 9", right ) do.
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Siphonophores are free-floating or swimming colonial hydroids. All siphonophores are predatory and should be treated with respect for their venomous sting. Some of the individual animals along the length of the colony provide tentacles for defense (dactylozooids) and food capture, while others may function as swimming bells (nectophores), aid flotation (pneumatophore), provide additional defense (bracts), digest prey (gastrozooids), or serve for reproductive functions (gonozooids.) Whether siphonophores are single individuals or colonies of well-integrated polymorphic hydroid and medusoid individuals is a matter of debate among specialists.
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You cannot go diving in New Jersey waters without seeing Comb Jellies. Up close, rainbow-like rows of tiny beating hairs called cilia may be seen - the Comb Jelly's only means of propulsion. Comb jellies do not sting, but they are still voracious predators, feeding on anything they can engulf. At night they may phosphoresce - watch the boat wake as agitated Comb Jellies flash in the dark like depth charges. Cnidarians are exclusively marine, although some are tolerant of brackish water as well.
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Naked Sea Butterflies Clione limacina resemble angels. They have a spindle-shaped body up to 1 inch long that is bluish and transparent, with pink to red-yellow areas. The shell is absent. The head is well developed and clearly evident because of an indentation on the upper part of the body. The body has robust flaps ( mantle lobes ) that are used for propulsion. Although it looks like a jellyfish, the Naked Sea Butterfly is a gastropod mollusk, related to snails and sea slugs, and does not sting.
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Thalia democratica
Although they may superficially resemble swimming siphonophores, salps are actually free-living tunicates. There are 6 genera of salps and all are transparent.
Tunicates are much more advanced in the evolutionary scheme of things than jellyfishes, having, for example, a circulatory system. The larvae actually even have several features in common with vertebrates, including the precursor of a spinal cord, but these are lost in the sac-like adults. Salps do not sting.
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Drifting In A Jellyfish Sea
Text and images by Herb Segars
It's late summer and I am 20 feet below the surface of the Atlantic Ocean off New Jersey. I am wearing long underwear, a waterproof ( and leak-proof, I hope ) rubber suit, 40 pounds of dive gear and a 30-pound weight belt to keep me from bobbing to the surface. A slight current forces me to grip the anchor line with one hand and take photographs with the other. I see a possible subject 6 feet away and watch as it drifts closer.
In the blink of an eye, I have set my focus and triggered the camera. The two underwater flashes attached to the camera fire and I hope that the results look as good as I envision. Between frames, I monitor my air supply and my time underwater. Thousands of planktonic subjects float by in the hour that I am below. Today turns out to he a good day - I run out of film before my time or air expires. Back on the boat, I dry off, change film and wait the required 1+ hours before making my next underwater photographic journey.
Capturing the underwater realm on film is a long and painstaking process. All my underwater work off New Jersey happens in the spring, summer and fall. In a good year, I am able to make 70 dives and shoot 70 rolls of film. When strong winds and rough seas bring a season of had weather, the number of dives and rolls of film taken drop to fewer than 20. In comparison, on a typical topside nature photography trip, I can shoot 70 rolls of film in a week.
This article first appeared in New Jersey Outdoors - Summer 1999
Might as well call this the squishy section of the website. These organisms ( they aren't even all animals ) are lumped together here for their rather unappealing consistency. Disney will never make an animated adventure about any of them. That's not a scientific way to classify things, but it works pretty well for the layman.
- Plant-like Animals ...
- Jellyfishes ...
- Echinoderms ...
- Worms ...
- Squids & Octopus ...
- Algae & Seaweeds ...
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Rare mauve stinger jellyfish found at the Jersey Shore. Its sting is 'intense,' scientists warn.
By Brianna Kudisch
NJ Advance Media for NJ.com
Aug. 31, 2022
Provided by Maggie McGuire
Maggie McGuire was at Sea Watch Beach in Manasquan with her family Monday when they spotted something unusual in the water - a small, umbrella-shaped, purplish-pink jellyfish speckled with dots. They scooped one up with their bucket and let it swim around in the water before eventually releasing it on the other side of the beach, away from swimmers.
"The water was literally filled with them," McGuire recalled. Her kids caught and released probably a dozen, she estimated, and other kids were doing the same. She did a quick search online, found a Facebook group - New Jersey Jellyspotters - and posted photos of the jellyfish. Two marine biologists reached out and informed her they were mauve stingers, a species rarely found on New Jersey beaches.
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very dangerous
This is a Pacific coast jellyfish that has been spotted along the East Coast for many years, but until recently has been uncommon. It is slightly larger than a quarter, about one inch in diameter. The sting of this jellyfish will send you to the hospital, not just people that are especially sensitive, but anyone. It is found in bays and inlets where it clings to seagrasses, it is not normally found in the open ocean. Your best protection against jellyfish stings is an exposure suit; even a lycra skin is thick enough to block the microscopic stingers.
- Clinging Jellyfish Fact Sheet
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