Thursday, September 16, 2010

Freshwater Jellyfish Found in Lake Charlevoix

If anyone except a wildlife biologist had called me to say they had found Jellyfish in northern Michigan I probably would have just said “yeah right”. Since it was such a biologist that called me though I took him seriously.

Turns out there is such a thing as a Freshwater Jellyfish and some of them have been found recently in Lake Charlevoix. Boaters noticed a large number of the small white creatures in the waters off of the lakes South Island and even managed to deliver a few live specimens to the Michigan Department of Natural Resources and Environments fisheries station in Charlevoix.

To the knowledge of the staff at the Charlevoix fisheries station this is the first time Freshwater Jellyfish have been found in the lake.  Because they seem to be able to spread so readily the stations biologist feels it a pretty good bet that they are also in Round Lake and possibly Lake Michigan.

Freshwater Jellyfish (Craspedacusta sowerbyi) have been found around the world including 44 of the 50 United States. Believed to have originated in China these small penny sized jellyfish were first noted in the U.S. in 1908 and now pop up in hundreds of locations whenever the condition are right. Explanations of how they have been able to spread varies. Some researchers suggest that they may have been brought into Europe and the United States on Chinese water plants that were popular around the turn of the century while others theorize that they may be carried from place to place by migrating waterfowl.

Freshwater Jellyfish can reproduce asexually which means by themselves. They do not need a male or female partner to reproduce. They can show up one year in very large numbers and not make another appearance for several years. They prefer locations with calm warm waters and are rarely seen in fast flowing streams or rivers. They feed on smaller plankton and microorganisms but can sting and kill small fish.

Like all jellyfish the freshwater variety is capable of stinging but because of their small size they are not capable of injuring people since they can not break through human skin.

More information about Freshwater Jellyfish can be found all over the internet by searching either their common or scientific name.


  1. I have a found these at lower crooked lake in delton Michigan...I was so amazed I actually caught one and brought it home...I still am amazed these creatures are amazing and awesome to watch

  2. We just found some and captured them out of Pleasant Lake MI. They are really cool looking and there are thousands of them! Really cool to find in our local lake!

  3. Discovered tens of thousands in Clear Lake, Barry County. Everyone looks at me like I'm nuts when I relate this story!

  4. My daughters found some in Crocker Lake in Twin Lake, MI. I'd never heard of this before so I had to Google it. Very cool to watch!

  5. We have these in our lake, My husband remembers seeing them there when he was a small child, he told his science teacher about it and he didnt believe my husband. well, gary took some to class in a jar and his science teacher nearly pooped, our lake is diamond lake, in tustin michigan. just south of cadillac.