Moon Jellyfish Facts (Animals of North America and Europe)

The most common method used to identify Moon Jellyfish is to select the fish from the port using the device. Moon jellyfish can be released into the harbor after a while and return to their natural habitat.

This fish is almost completely translucent. The saucer jelly is usually about 25-40 cm in diameter and can be identified by its four horse-shaped gonads that are easily visible from the top of the bell. Moon jellyfish feed by collecting mollusks with plankton, medusae and its tentacles and bringing them into its body for digestion. This fish is only capable of limited speed and it flows with current even with swimming.

Habitat and Range of Moon Jellyfish

Moon Jellyfish can be found anywhere with seawater with temperatures of 48 and 66 degrees. Yet the Aurelia aurita has also been found in water with a temperature of 21 degrees or as high as 88 degrees Fahrenheit. This species of fish is also commonly found near the shore in harbors and clouds. Moon Jellyfish live in debris water with a salt content of 0.6% which is very low. This fish also favors the existence of a temperature of 9 ° C to 19 C.

Moon jellyfish are commonly found in the cold waters of North America and Europe, especially off the coasts of New England and Canada. Experts have noted a significant increase in the population of this fish in the last few decades. Climate change and overcrowding have led to earlier drops in the population of many species of their natural predators from the Moon Jellyfish. Other threats to the survival of Moon Jellyfish include bacterial infections and which can be detrimental to the already weak physical conditions of this fish.

Reproduction of Moon Jellyfish

Saucer jelly breeds during the summer. While the females of this fish lay eggs and their male species release their sperm into the sea at 24 hour intervals. That behavior of Aurelia aurita demands a lot of energy. This process will usually cut the fish. In the wild one can only expect the Moon Jellyfish to live for about half a year and this fish will die immediately after reaching adulthood.

Distribution of Moon Jellyfish

The saucer jelly belongs mainly to the Atlantic Ocean, the Indian Ocean and the Pacific Ocean. This fish prefers a temperate ocean with a consistent flow. During the summer months of July and August the relationship between summer hypoxia and saucer jelly distribution is prominent where temperatures are high and dissolved oxygen is low. Out of the three environmental conditions tested, the bottom DO has the most significant impact on this jellyfish abundance.

The abundance of this fish is highest when the concentration of dissolved oxygen at the bottom is less than 2.0 mg L-1. Aurelia aurita shows strong tolerance to low DO conditions and that is why the population of Moon Jellyfish is still relatively high during the summer. The concentration of Moon Jellyfish is lower than normal.

During July and August it was found that this fish of 250 individuals consumes approximately 100% of the mesozooplankton biomass in the aggregate Seto Inland Sea. Other large fish predators that are also present in these coastal waters and exhibit these fish do not appear to have the same high tolerance to low DO concentrations. Moon Jellyfish's diet and predatory activity are significantly reduced.

This allows for less competition between Aurelia aurita and other fish predators for zooplankton. Low DO concentrations in coastal waters such as Tokyo Bay and Seto Inland Sea in Japan prove to be beneficial for this fish in terms of food, growth and survival.

Behavior of Moon Jellyfish

The saucer jelly swims through the bell-shaped upper part. This type of fish floats horizontally and Moon Jellyfish keeps the bricks close to the surface at all times. Moon Jellyfish enables tentacles to spread over a large area and so these fish can better capture food.

Aurelia aurita can live more than 12 months in adulthood and while the polyp of Moon Jellyfish can live for decades without their bodies. Currently there is no real threat to the population of Aurelia aurita, while this fish can bring some bites that can be fatal to humans. But Moon Jellyfish in general are very mild and are not considered dangerous.

Diet of Moon Jellyfish

Saucer jelly is mainly made of water. In fact, 95% of Moon Jellyfish's body is made up of water. Moon Jellyfish is a carnivorous animal and to say that this fish feeds other protein rich aquatic animals. Moon Jellyfish's menu includes minute plankton, fish eggs and larvae, crabs and shrimp.

Aurelia aurita does not use her legs or tail for locomotion. Instead the fish goes through the beating made inside its bell. Moon Jellyfish live in the ocean currents and pass through its mornings. The minutes in which the Moon Jellyfish feeds the animals are often stung by the stinging cells of the fish and are usually found drawn on the tentacles of the Moon Jellyfish. Others get trapped in the lining of their trapped prey and are then transported along the inner canals of the saucer jellyfish and eventually the fish accumulates the whole food in its stomach.

Feeding of Moon Jellyfish

The saucer jelly feeds on its prey by biting with nematocysts found on its long tentacles. Food is collected on the surface of Moon Jellyfish which is trapped in saliva. The Moon is moved closer to the margin by the actions of the Jellyfish flagella. The Moon Jellyfish is collected on lappets and again moved by the flagella into eight separate canals that protrude from the branches and run into the abdomen.

Occasionally Moon Jellyfish are also found feeding on gelatinous zooplankton such as hydromedusae and ctenophores. These fish break down the digestive enzymes from the serous cell. It is little known about the needs of vitamins and minerals to this fish but due to the presence of some digestive enzymes we can generally speculate that Moon Jellyfish can process carbohydrates, proteins and lipids.

Information about Predators

Saucer jelly has a high content of polyunsaturated fatty acids compared to other types of prey which provides important nutrition to predators. Moon Jellyfish is eaten by a variety of predators, including sea sunfish, leathery mountain sea turtles, scyphomedusa Phacellophora camtschatica and very large hydromedusa.

It was recently reported from the Red Sea that this fish was preyed upon by two herbivorous fish according to the season. This species is also fed to sea birds and may be more interested in the frequent amphipods and other small arthropods of the Moon Jellyfish but in any case the birds harm the Moon Jellyfish which is often found on the bay surface.

Conservation of Moon Jellyfish

Moon Jellyfish plays an important role in the transformation of pelagic organic matter. Since Moon Jellyfish feed on copepods and fish larvae it can affect the plankton community. Moon Jellyfish are survivors and Moon Jellyfish thrive in dirty, polluted and low oxygen water.

Body system of Moon Jellyfish

Saucer jelly does not have respiratory parts like gills, lungs and trachea. Moon Jellyfish breathe by scattering oxygen from the water through a thin membrane covering its body. These fish can be excreted inside the gastrovascular cavity, low oxygenated water, and high oxygenated water by chain action. Thus the diffusion of oxygen in the Moon Jellyfish by the cell is increased. Larger surface area membranes with volume ratios help Moon Jellyfish disperse more oxygen and nutrients into the cells.

Moon Jellyfish's basic body plan includes many parts. In this fish its food travels through the muscular route while the radial canals help disperse the food. Moon Jellyfish have a nerve grid that is responsible for the contraction of muscles in swimming and food responses.

Information about Blooms and grouping

The group of Moon Jellyfish is called Smack. Moon jellyfish gather in large groups called peacocks with more than a thousand people. The formation of peacocks in this group of fish is a complex process and depends on the temperature of the oxygen content, sea currents and nutrients.

Other Information

Kingdom : Animalia

Class : Scyphozoa

Family :  Ulmaridae

Order : Semaeostomeae

Phylum : Cnidaria

Genus : Aurelia