Local waters are home to freshwater jellyfish

There is something strange in the waters of the Clarion River: freshwater jellyfish. You will need to look closely to see them. Even the largest are only the size of a penny.

Wayne Minich Jr., the former superintendent of Clear Creek State Park, recalls seeing the tiny creatures 50 years ago in the Clarion River.

“People could catch them off of piers in the river,” said Minich. “You have to look closely to find them.”

According to Pennsylvaniajellyfish.org, “The appearance of the jellyfish is described as sporadic and unpredictable. Often, jellyfish will appear in a body of water in large numbers even though they were never reported there before. The following year they may be absent and may not reappear until several years later. It is also possible for the jellyfish to appear once and never appear in that body of water again.”

According to freshwaterjellyfish.org, there are two schools of thought as to the origin of the freshwater jellyfish. One is they originated in the upper Yangtze River basin in China, where populations are still found today. They then were discovered in water lily tanks in Regents Park in London in the late 1800s, presumably having arrived there as polyps on the imported plants.

There is nothing specific in the literature as to how the organisms might have gotten from either China or London to the U.S.

Another story that can be found in the literature is they originated in South America and made their way to the U.S. in bilge water of ships. About the same time (late 1800s), the polyp form was discovered in Tacony Creek near Philadelphia.

According to the freshwaterjellyfish.org, jellyfish have been spotted at numerous places in the Clarion River: the dam, near Clarion, off Interstate 80/Route 322 (2006, 2008, 2013); near I-80 bridge/Clarion Bridge, Route 322/I-80 (2007, 2008); Clarion River, Clarion, near Toby Bridge, North Fifth Avenue (1995, 1998, 2007, 2008, 2014); Clarion River, Clarion, Penelec dam (1995); Clarion River; Piney Reservoir, Clarion, off I-80 (1995, 2007, 2008); Clarion River, Clarion, above Piney Reservoir (1996); Clarion River, Clarion, near Piney Dam, off I-80 (1999, 2006, 2013); Clarion River, Piney Reservoir, Clarion, Route 322, (1995, 2005, 2012); Clarion River, Clarion, Maple Lane West, also Miola Road (2008); Clarion River at mouth of Trout Run, near South Fifth Avenue (2018); Clarion River, Clarion (2002).

Jellyfish have also been found in other places in Clarion County, including a farm pond, next to Little Piney Creek, near Clarion, Monroe Township, Lawrence Road (2016) and a small farm pond, near Callensburg, Route 368 (2011).

Jellyfish have also been spotted in Venango County at: Horn’s Pond, near Oil City (1999); Lake, Eagle Rock (2007); Oil Creek (1995); Private pond, Emlenton, I-80 (2010); Private pond, Potters Falls Road, Rockland Township, (2010) and Two Mile Lake (Two Mile County Park), near Oil City, Route 428 (2005).

The website said freshwater jellyfish could enter a pond in a variety of ways. For example, they could have entered in the polyp stage attached to plants. The plants could have been carried in by birds, on the props of boats, on the bottom of boat trailers or in the buckets of fishermen.

They also could have entered in the medusa form in the bilge water of boats, in the water of bait buckets or by flooding from another site.

Like true jellyfish, they have stinging cells. This mechanism is designed for feeding. It is highly unlikely that the microscopic stinging barbs can penetrate the human skin to inflict a sting.