I went kayaking near Hammonasset Beach State Park in Connecticut at the end of June. My son and I saw quite a few reddish jellyfish which, as it turns out, are known as Lion's Mane Jellyfih.
This has apparently been a good year for the jellies. The Lion's Mane are food for the Leviathan Leatherback sea turtles.
Here are some excerpts from a New York Times article from July 22:
...[J]ellyfish have always been a blobbish summer menace to swimmers, fishermen and little children’s curious fingers.
But this year they have been even more of an annoyance than usual, arriving early and perplexing fishermen and beachgoers from Toms River, N.J., to Long Island and beyond. Biologists have several theories about why the jellyfish, particularly one breed, the lion’s mane, have turned out about a month before they are usually seen here.
Kenneth W. Able, director of the Rutgers University Marine Field Station in Tuckerton, N.J., said the early arrival could have something to do with recent winds from the south that blew away the sea’s warmer surface water, allowing an upwelling of cold water, which the lion’s mane loves.
Edward Enos, the superintendent of the Aquatic Resources Division for the Marine Biological Laboratory in Woods Hole, Mass., said conditions may have been perfect for an unusual number of baby jellyfish, called polyps, to survive.
“It’s nature,” Mr. Enos said. “It’s like some years you have beautiful, big blooms of dandelions in your yard, and sometimes not.”
On Monday, a steady stream of jellyfish undulated in the olive-colored water of the Hudson River between 79th and 98th Streets, where the swimmers had encountered them the day before. Their centers shifting up and down with the light tide, they were about six inches in diameter and looked like large floating paper cupcake wrappers stained in the center with red icing.
Splayed on a hard surface outside the water, they spread out into a gooey reddish-, orange-, olive- and cream-colored circle, some nearly a foot wide....
Jim Gilmore, director of marine resources for the State Department of Environmental Conservation, said that last Friday he started receiving calls about jellyfish. On Monday, he got a lot. Most years he doesn’t get jellyfish reports until August, he said.
John Lipscomb, a patrol boat operator for the Hudson Riverkeeper, an environmental group, said he saw a lion’s mane in the Harlem River for the first time last Monday. It was floating in a slew of garbage in the river.
“I looked over and in this massive soup of trash and debris was this beautiful pulsating jellyfish,” he said.
John Waldman, a professor of biology at Queens College, said that jellyfish may have moved upriver because of a lack of rain this year, which has pushed the salt water further upstream.
About a week ago, while boating with her mother on the Navesink River in New Jersey, 11-year-old Marissa Leli had her first encounter of the summer with a lion’s mane.
“It was all red, and the tentacles looked kind of scary,” said Marissa, who lives in Rumson, N.J., with her mother, Cindy Leli, 37. On Saturday, they were enjoying the ocean waves in Sea Bright, N.J., although they were on guard for jellyfish...
Mr. Grant, of the Sandy Hook Ocean Institute, said he first noticed them in April when young jellyfish the size of golf balls were turning up in fishing nets.
“This is a banner year if you like the look of jellyfish,” he said on Saturday afternoon after having netted a specimen, six inches in diameter, in the Atlantic Highlands Municipal Marina...
The lion’s mane, which can grow to eight feet in diameter and sport tentacles more than 100 feet long in arctic regions, usually does not exceed a foot in diameter in its southernmost range, Mr. Grant said. But the larger the jellyfish, the more painful the sting.
Bill Mack, 70, chief of beach operations and water safety in Sea Bright, said lifeguards were equipped with spray bottles of vinegar, which neutralizes the jellyfish’s venom.
“We spray it on people and they go away happy,” he said...