There have been increased sightings of Lion's Mane jellyfish, which can grow up to 8 feet wide, up and down the New England coast — including near Nahant Beach. WGBH Morning Edition anchor Joe Mathieu spoke with with assistant curator of the New England Aquarium's Fishes Department, Steve Spina, to learn more about the massive jellyfish. The transcript below has been edited for clarity.
Joe Mathieu: This thing is massive. I'm sure I've never seen one. Are they a rare sight here?
Steve Spina: No, they're pretty common in New England waters, although the biggest ones are found north of here. They extend all the way up into the Arctic. The ones in New England are usually not eight feet across. They're usually quite a bit smaller.
Mathieu: So that would be an extreme version?
Spina: Yeah, as you get further north they get larger. Recently, though, there have been a few in Maine that have been between four and five feet across, and that's really large. That's pretty unusually large for New England waters. But the ones we see around here are usually between maybe eight and 14 inches wide.
Mathieu: Just the thought of swimming into one of these things gives me the creeps, Steve. I suspect they're as dangerous, maybe more, than any other jellyfish.
Spina: Well, they do have a pretty strong sting. Not anything that would kill you the way some some of the jellyfish in Australia can, but they'd certainly cause a pretty severe sting and a rash, and it wouldn't be fun.
Mathieu: It would not be a fun day. How do you treat that, and should people be worried about bumping into these this summer?
Spina: Yeah, I think they should be worried about it. They have very long tentacles, which is one of the dangers. Even if you see one that's eight or 10 feet away, those tentacles can stretch and extend to where you're standing or swimming.
Mathieu: Oh my God!
Spina: Yeah, the longest tentacles on the biggest specimens go over 100 feet.
Mathieu: You're not making me want to jump in the ocean here, Steve.
Spina: No. If you see lions manes in the ocean, I'd probably go on the beach for a while.
Mathieu: So if somebody is stung, what do you do?
Spina: One of the most common treatments that people recommend [is] to use vinegar. I think lots of times lifeguards might have vinegar on the beach just in case someone gets stung by a jellyfish.
Mathieu: Do they do they move around? Will they go to another part of the country from here?
Spina: Well, they're ocean drifters. They're really planktonic, so they're kind of at the mercy of the currents. And they get swept around the ocean, inshore and offshore, very often by currents, which is why they're pretty unpredictable. And sometimes they're in deeper water. Sometimes they get pushed in closer to beaches.
Mathieu: Does anything eat these things?
Spina: They're eaten by sea turtles [and] ocean sunfish, which we also see in our waters in the summer. Sunfish can get quite large. They can get to be about eight [to] 10 feet as well. They're just part of the fauna here.
Mathieu: Not going to show up on a seafood menu any time soon, though, I don't think.
Spina: No, I don't think so. There are some edible jellies, but these aren't one of them.