{"id":1686,"date":"2014-05-01T08:57:55","date_gmt":"2014-05-01T12:57:55","guid":{"rendered":"http:\/\/ncseagrant.ncsu.edu\/coastwatch\/?page_id=1686"},"modified":"2024-09-19T15:26:44","modified_gmt":"2024-09-19T19:26:44","slug":"naturalists-notebook-the-rise-of-the-jellies","status":"publish","type":"post","link":"https:\/\/ncseagrant.ncsu.edu\/coastwatch\/naturalists-notebook-the-rise-of-the-jellies\/","title":{"rendered":"Naturalist’s Notebook: The Rise of the Jellies"},"content":{"rendered":"\n\n\n\n\n
It’s a hot summer day and the beach is packed. The cool water is refreshing and inviting as many beachgoers jump in for a dip. Somewhere down the beach, a swimmer flags down a lifeguard, his leg puffy and red.<\/p>\n\n\n\n
He’s been stung by a jellyfish. After getting first aid, the swimmer has a story \u2014 and some data.<\/p>\n\n\n\n
Suspecting that jellyfish are increasing in waters off North Carolina, researchers are asking for the public’s help in spotting these slimy creatures around our shores.<\/p>\n\n\n\n
They are seeking details for single sightings or larger events, such as when surf-zone fun on the Outer Banks came to a halt earlier this year. A swarm of sea nettles unexpectedly invaded the coastline for about four days, stinging some folks who braved the waters and keeping many others on the sand.<\/p>\n\n\n\n
Annually about 150 million people are stung by jellyfish worldwide, with some fatalities and hospitalizations, according to the National Institutes of Health.<\/p>\n\n\n\n
The Charlotte Observer remarked on the increase in jellyfish stings in Folly Beach, S.C., in August where reported stings jumped from 15 to 150 in a 24-hour period. In past years, some North Carolina beaches such as Carolina Beach have flown colored flags to warn beachgoers of the slimy threat lurking in the water.<\/p>\n\n\n\n
But it’s not just stings causing problems. These pulsing creatures can wreak havoc around the world, even causing power outages by clogging nuclear cooling systems in California and the Philippines.<\/p>\n\n\n\n
“These gelatinous masses pose dire consequences for the environment and human activities such as fishing, shellfishing and tourism,” says Vicki Martin, a biologist at Appalachian State University.<\/p>\n\n\n\n
Martin has been growing box jellies in her lab for years and is currently researching various conditions under which they grow, varying temperature, light, feeding regimes, the pH scale of different sea water concentrations and the size of the containers they are grown in.<\/p>\n\n\n\n
Jellyfish are predators of fish eggs and larvae, thus they can affect fish populations and the balance of the ecosystem, Martin adds.<\/p>\n\n\n\n
Although Martin says it’s clear that the jellyfish population has been on the rise, limited data make it difficult to pinpoint why.<\/p>\n\n\n\n
“It appears that a combination of manmade factors such as eutrophication of the oceans and global warming are leading to the massive blooms,” she explains. Eutrophication occurs when excessive nutrients in a body of water cause a dense growth of plant life; then decomposition of the plants depletes the supply of oxygen, leading to stress to and sometimes death for some animal species.<\/p>\n\n\n\n
Several factors play a role in the reproduction of jellyfish, she adds. By tweaking certain variables in her lab, Martin finds that box jellyfish can thrive in almost any environment. For example, the normal pH of seawater is around 7.9, where 7 is considered neutral. While polyps, an early stage in the jellyfish life cycle, grow nicely at this pH, Martin’s experiments have revealed they also can reproduce and grow in the range of pH 3 to 9, showing that jellyfish can accommodate to ocean acidification, at least to a point.<\/p>\n\n\n\n