(Oskaloosa, IA) -- An Iowa teen has spotted a rare freshwater jellyfish at an Iowa wildlife area. Oscar Schiferl [[ SHIFF-erl ]] of Oskaloosa says he spotted it in the water while he was fishing. A Department of Natural Resources expert says the species is native to Asia and rarely found in Iowa waters. It was found at Russell Wildlife Area, north of Oskaloosa.
“I was fishing in between a tree that fell to see if I could catch a bass,” Schiferl said. “I saw the jellyfish swimming in the water, and my dad didn’t believe me at first, so I caught one to show him. He was like, ‘That’s actually a jellyfish.’”
The freshwater jellyfish, are known scientifically as Craspedacusta sowerbii, and are native to Asia and rarely found in Iowa waters according to Kim Bogenschutz, Aquatic Invasive Species Coordinator for the Iowa Department of Natural Resources. She says it's the second sighting in the state this fall.
“This is the second sighting we’ve had just in the past week,” Bogenschutz said. “One was at a pond near Lake Panorama in Guthrie County. Even with these recent sightings, it’s still a cool and unusual find.”
The young angler’s excitement grew as he found more jellyfish in the pond.
“I saw a whole lot more of them out there,” Schiferl said. “I caught about 20, but my dad wouldn’t let me keep more than two.”
Schifer’s discovery sparked excitement at Oskaloosa High School, where he brought one of the jellyfish to school in a mason jar to share with his friends and teachers. “I knew no one would believe me unless they saw it,” he explained.
His science teacher, Stephanie Campbell, was initially skeptical. “At first, I thought he was joking,” Campbell said. “I thought he might have grabbed it from an aquarium. But when he told me he found it at Russell Wildlife, I knew we needed to take it seriously.”
The appearance of freshwater jellyfish in Russell Wildlife raises important ecological questions. While these jellyfish are not dangerous to humans—they are too small to sting—Bogenschutz emphasized the importance of monitoring non-native species.
“These jellyfish probably arrived here unintentionally, likely through aquariums or aquatic plants,” Bogenschutz said. “While they don’t seem to have invasive qualities or pose a major threat to native species, it’s crucial to prevent further spread.”
She also stressed the importance of responsible pet ownership and conservation efforts. “The message is simple: don’t dump aquariums into lakes or ponds. Even small actions like that can introduce species that don’t belong and disrupt ecosystems.”
Though small, these jellyfish—often called peach blossom jellyfish—feed on plankton, a food source vital to many fish and aquatic organisms. However, because their appearance is sporadic and they don’t seem to outcompete native species, they are not considered an immediate environmental threat.
With colder weather approaching and frost warnings in effect, Bogenschutz noted the jellyfish may not be around for long. “These jellyfish are sensitive to temperature changes,” she explained. “As the water cools, they’ll likely disappear back into their resting stages. But it’s moments like these, when students find something unexpected, that remind us how important it is to stay curious and observant.”