A closeup view of the clinging jellyfish (Gonionemus vertens), an invasive species from the Pacific Ocean that packs a painful sting. (Photo courtesy of  the American Littoral Society. Click to enlarge)
By JOHN T. WARD
The clinging and stinging jellyfish that prompted the Navesink Maritime Heritage Association to cancel this summer’s River Ranger program is clearly something to be avoided.
Still, the American Littoral Society is hoping to get a closer look at the dime-sized creatures.
“Scientists are trying to figure out what to do about” the invasive species, which has been spotted in the Navesink and Shrewsbury rivers, and have stung at least one local victim, according to a spokesperson for the Sandy Hook-based organization. But first, they need more data.
So the organization is seeking help, via these three methods:
1) Report sightings of clinging jellyfish by either emailing photos and the locations to [email protected] or via the Marine Defenders App (downloadable for iPhone).
2) Only if you feel you can do it safely, capture the clinging jellyfish in a jar for pick-up, contact us at 732-291-0055 and we will get it to the jellyfish team at Montclair State University. Obviously, do not touch a stinging jellyfish with your bare hands. We suggest you wear rubber gloves, and use a net to scoop the jellyfish up, then deposit it in a clean glass jar in river water and screw the lid on. They are more active at night so shining a light into the water will help.
3) Allow your dock or bulkhead to be sampled for clinging jellyfish by calling or emailing us at the above email and phone number.
Why are there so many in our rivers? Here’s an answer from a flyer distributed locally by the society:
The exact reasons for the proliferation of jellyfish in our rivers is not 100% clear. Most likely it is a combination of factors, but the recent increase in jellyfish blooms in high population areas points to some likely culprits. Human activities—specifically, pollution (sewer and storm-run-off), seafood harvest (reducing jellyfish predators), eutrophication (caused by excessive use of fertilizer on our lawns, which cause algae blooms that jellyfish thrive on), hard substrate additions (the increase in docks and bulkheads), introduction of invasive species (via ships) and climate change, are throwing off the natural equilibrium of our rivers.