Surprising predator in NJ waters may reduce clinging jellyfish
For years, New Jersey researchers have been trying to get rid of stinging sea nettles, but they might actually be serving a useful purpose, despite being a nuisance to swimmers.
An abundance of sea nettles in the Navesink and Shrewsbury rivers appears to be keeping down blooms of the rare and dangerous clinging jellyfish seen last month in those same rivers, according to Dr. Paul Bologna, director of Marine Biology and Coastal Sciences at Montclair State University.
"In the lab, we've actually sort of put these two species together and sea nettles will eat clinging jellyfish," Bologna said.
According to Bologna, researchers learned a lot about sea nettles from Barnegat Bay. He said the creatures like to drag their tentacles along the bottom of bay, swim in grass beds and pick up animals as big as they can feed on.
"The reason that I put these two together in the lab was because I knew that sea nettles eat other types of jellyfish, and they would be in the same waters that they would encounter clinging jellyfish," Bologna said. "It takes a little while for the sea nettle to grab hold of the clinging jellyfish, but once it gets it, it sucks it right in and eats it pretty rapidly."
Bologna described the fact that sea nettles might be playing an important role in keeping clinging jellyfish populations down as a "cloud that might have a silver lining." Ultimately, researchers would like to address both the clinging jelly fish from a human health perspective and the other jellyfish in the area that also pose a threat to fish and human enjoyment of water, according to Bologna.
There have been reports of clinging jellies in the Manasquan River area, but no confirmed reports from Barnegat Bay, Bologna said.
"In our sampling so far, we have not encountered a single clinging jellyfish in Barnegat Bay," he added.
Clinging jellies created a scare in June, when a 20-year-old man was stung in the Shrewsbury River and had to be hospitalized for days.