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The Incredible Jellyfish

There wasn’t much happening on this earth 700 million years ago. There were no dinosaurs, fungi or even trees, but there were jellyfish. Amazingly, jellyfish generally don’t live very long, some have a life span of few days, some a year, yet species have been around since the earliest days of the earth. There are some 2000 known species of jellyfish. Some experts believe there could be as many as 300,000 species. One species, the Turritopsis dohrnii jellyfish, which actually reproduces itself as parts of its body age and die may never die. It is possible that this process may have allowed some to live for thousands of years. Some species are so tiny that they can only be seen with a microscope. The smallest are the Staruocladia and Elutheria measure only 0.02 inches in diameter. On the other end of the scale, the largest is the Momura’s Jellyfish, which measures 6.5 feet and weighs 440 lbs. Nomura’s jellyfish reside primarily in the waters between China and Japan, primarily centralized in the Yellow Sea and East China Sea. The Lion’s mane or Cyanea capillata species is one of the largest know species and is found cold northern seas.
Jellyfish are something special to watch as they gracefully undulate in the water. Their both elegant and mysterious but take them out of the water and they turn into a blob of shapeless jelly. Surprisingly, jellyfish have no brains. Nor do they have blood, lungs or a heart. Considering they are made up of 98% water they are remarkable. In place of a brain jellyfish have an elementary nervous system, which detects light, vibrations, and chemicals in the waters. The also sense gravity. They absorb oxygen through their gelatinous skin. These systems make it possible for the jellyfish to navigate. Some species of jellyfish have eyes and “teeth,” or rather thin hairs that pull in and bite down on their food.
The Britannica encyclopedia describes jellyfish in this way, “Jellyfish are any plankton marine member of the class Scyphozoa (phylum Cnidaria), a group of invertebrate animals composed of about 200 described species, or of the class Cubozoa (approximately 20 species). The term is also frequently applied to certain other cnidarians (such as members of the class Hydrozoa) that have a medusoid (bell- or saucer-shaped) body form, as, for example, the hydromedusae and the siphonophores (including the Portuguese man-of-war). Unrelated forms such as comb jellies (phylum Ctenophora) and salps (phylum Chordata) are also referred to as jellyfish. Scyphozoan jellyfish can be divided into two types, those that are free-swimming medusae and those that are sessile (i.e., stem animals that are attached to seaweed and other objects by a stalk). The sessile polyp-like forms constitute the order Stauromedusa”
You might wonder what in the world are jellyfish good for beside stingy the daylights out of swimmers who have the unfortunate luck to make contact with one in the water. Don’t blame the jellyfish, remember they have no brains. What is happening they are instinctively reacting to your presence. Jellyfish use the stinging cells in their tentacles to paralyze their prey before eating them. The cells are called nematocysts, these small compartments house a tiny, needle-like stinger. When triggered, the chamber opens, letting ocean water rush in, which causes the stinger to shoot out and venom to be released. They are also a source of food for sea anemones, tuna, swordfish, sharks, sea turtles and penguins. As the old lady said, “there is no accounting for taste”.
Jellyfish are no pikers when it comes to their taste for food. They consume fish, shrimp, crabs, and tiny plants and play a role in balancing the populations and providing nutrition in the forms of fatty acids to their predators.
The giant lion’s mane jelly fish seem to prefer the colder waters of the Artic and the norther parts of the Pacific and Atlantic oceans. They sometime venture into the Baltic Sea. The largest concentrations of lion’s mane jellyfish are in the colder parts of the Arctic, northern parts of the Pacific and Atlantic oceans. Occasionally, they migrate into southwestern areas of the Baltic Sea. Occasionally, during the winter months, they are spotted in the Cheaseapeake Bay. Lion’s mane jelly fish are constantly moving and mostly one or two and rarely in swarms. They are commonly seen in the North and Irish Seas, the English Channel and in parts of Scandinavia. Actually, free-swimming scyphozoan jellyfish can be found in all the oceans of the world and often fund drifting along the shoreline.

Sea wasps are box jellyfish and the deadliest jellyfish in the world. They have box-like bodies with tentacles extending from each corner. They live in tropical areas around the world. They are found mainly on the northern coast of Australia and the Indo-Pacific Ocean. There are more than 40 species of box jellyfish. The Australian box jellyfish is the most venomous jellyfish in the world.
Most people believe the Portuguese man of war is a jellyfish. Technically they are not, but they do resemble jellyfish. They are found in tropical waters of the Atlantic, Pacific and Indian oceans and the Caribbean Sea. Portuguese men-of-war have balloon-like floats that keep them above the water. Below the water, they have long strands of tentacles and polyps that grow to about 30 feet long.
Regardless of what species they are the sting of a jellyfish can be very painful even deadly. The symptoms of jellyfish stings depend on the type of jellyfish you made contact with. If you have a minor jellyfish sting, you may feel slight pain, itching, burning or throbbing. A jellyfish sting may look like a rash with red, purple or brown patches.
More serious jellyfish stings can cause greater harm. You should seek medical help right away if you have more severe symptoms.

  1. Generally mild jellyfish stings can be treated by following these steps: Carefully pluck visible tentacles with a fine tweezers.
  2. Soak the skin in hot water. Use water that’s 110 to 113 F (43 to 45 C). It should feel hot, not scalding. …
  3. Apply 0.5% to 1% hydrocortisone cream or ointment twice a day to the affected skin.
    More serious stings should be treated by a medical professional.
    You may be surprised to learn that while jellyfish are not too often eaten in the United States there are many countries whose people eat them regularly. There are many ways to eat jelly fish including shredded or sliced thinly and tossed with sugar, soy sauce, oil, and vinegar for a salad. It can also be cut into noodles, boiled, and served mixed with vegetables or meat. We are told properly prepared jellyfish has a delicate flavor and surprisingly crunchy texture. It is important to know which jelly fish are safe to eat before you venture into eating them.
    If you ever wondered what that glow in the bowl you may have seen when you ventured into the head one night on your boat. Or what was that glow trailing at night in the wake of your boat. You might have seen an eerie blue glowing the surf at a beach at night. was. Know that is bioluminescence. Bioluminescence is light produced by a chemical process within a living organism. The glow occurs when a substance called luciferin reacts with oxygen. This releases energy, and light is emitted. Jelly, pretty smart for a no brainer.