Clinging to a jellyfish link

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What does Vladivostok, Russia, have in common with Sengekontacket Pond?

Besides having complicated names to spell, they’re home to clinging jellyfish, known by their scientific name, gonionemus. They’re small, they attach to eelgrass and seaweed, and for pintsize jellies, they pack a powerful sting, causing severe pain, respiratory problems, and neurological symptoms.

Research by scientists at Woods Hole Oceanographic Institution (WHOI), including some field work at Sengekontacket and Farm ponds, has yielded interesting genetic connections to clinging jellies found off the coast of Russia. “I feel like I’m solving a mystery,” said Annette Govindarajan, a biologist at WHOI and lead author of a paper published April 18 in the journal Peer J. “We may not be dealing with the species we thought we were.”

Such is the life of a scientist.

Ms. Govindarajan has been doing research at WHOI for 21 years, and did her thesis on jellyfish evolution and their complex life cycles. “People are fascinated by them,” she said. “They’re beautiful creatures, gorgeous animals. It’s too bad they can cause such extreme pain.”

The frequency of stinging reports on Cape Cod and the Islands prompted Ms. Govindarajan to put together her recent study. In the process, she and other researchers discovered a genetic link between clinging jellies in the North Atlantic, the North Pacific, and waters off Vladivostok.

There is earlier research on clinging jellyfish, dating back to 1894 in Woods Hole, that has been useful in the more recent finds. Clinging jellyfish first appeared in the Cape Cod area in 1894, but following an eelgrass die-off, their numbers dwindled and nearly vanished in the 1930s, according to a WHOI press release. It wasn’t until 1990 that reports of the tiny, coin-size clinging jellies reappeared, and stung humans reported their experiences.

Ms. Govindarajan and her colleague, WHOI researcher Mary Carman, suggested in a previous paper that an invasion from a toxic population had occurred, WHOI explains in its release. The new study shows a more complex story that requires still more study, Ms. Govindarajan said. Clinging jellies from the two regions share “one genetic variant or haplotype,” Ms. Govindarajan said. They may be a mix of native and invasive species.

Ms. Govindarajan worked with Ms. Carman and colleagues Marat Khaidarov and Alexander Semenchenko from the A.V. Zhirmunsky Institute of Marine Biology, National Scientific Center of Marine Biology, Far East Branch, Russian Academy of Sciences, in Vladivostok, and John Wares from the University of Georgia. Seven variants were uncovered, some of which were specific to only one location, and others that were shared among communities in distant locations.

What Ms. Govindarajan hopes to do next is look for additional variations in the jellyfish DNA sequences. “That will be helpful for us to determine how they get around,” she said. “It will also help us understand where stinging forms are, so people know and can stay away. It will help us figure out, How are they spreading? Is there something we are doing that is making them spread?”

The clinging jellies start as tiny polyps, about a millimeter in size, Ms. Govindarajan said. So it’s possible they travel on a blade of eelgrass, on a shell, or even the bottom of a boat.

People shouldn’t panic about the clinging jellies and their propensity to sting, she assures the public. They’re typically in places with high concentrations of eelgrass, which isn’t conducive to sunbathing or swimming. But if people do encounter them, she’d like to hear about your sightings or stings by email at afrese@whoi.edu.

Research done for the most recent paper was funded with grants from Woods Hole Sea Grant, Nantucket Biodiversity Initiative, the Kathleen M. and Peter E. Naktenis Family Foundation, the town of Oak Bluffs Community Preservation Committee, and the Russian Science Foundation. Ms. Carman obtained the funding from Oak Bluffs as part of her research into invasive species in Farm and Sengekontacket ponds.

Ms. Govindarajan is now looking for more funding to continue her studies into the clinging jellies. And she’ll try to do it while keeping her no-sting streak alive. “Sooner or later it could happen,” she said. “I try to be very careful with them.”