Freshwater Jellyfish

Freshwater jellyfish can be seen in swarms from June through September.

Size of the freshwater jelly fish in Lke Ouachita. Freshwater Jellyfish Craspedacusta sowerbyi are umbrella shaped and are translucent with a white or green tint and are usually less than 1 inch (25 mm) in diameter. They feature four long tentacles for swimming and many shorter ones in-between for feeding on zooplankton.

August and September are peak months for jellyfish sightings when Lake Ouachita water is warm and food is abundant.

The jellyfish will be floating or swimming gently just below the surface of the water where they can easily be seen by the naked eye. Often they will surface in large numbers called "blooms". Sunny days are especially good for spotting jellyfish. They can be seen at depth and floating on the surface from the middle of the lake to the shoreline

These jellyfish do possess stinging cells (cnidocytes) to harpoon prey, but they aren't big enough to penetrate human skin. While they can be found in many warm-water settings across the United States, Lake Ouachita 's clean waters have allowed the jellyfish to reproduce in numbers large enough to be noticed by the average observer.

Piccture courtesy of USGS
The tentacles contain hundreds of special cells called cnidocytes. The cnidocytes contain the nematocysts that are used to capture prey. Often, large flat sex organs called gonads hang from the underside of the jellyfish. These organs make the jellyfish easier to spot because they are not translucent.

Jellyfish found in Lake Ouachita

The stinging cells (cnidocytes)are designed for feeding, as the cnidocytes are utilized to paralyze macroinvertebrates and even small fish.

More on the freshwater Jellyfish.
The Reproduction cycle of fresh water jellyfish.
Freshwater Jellyfish - Gen-yu Sasaki, Japan
Missouri Department of Conservation:  Feshwater Jellyfish



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