In September, North Carolina residents reported White Spotted Jellyfish along several beaches. At the end of October, South Carolina locals have recently reported large, invasive jellyfish near Myrtle Beach as well.
The massive Australian spotted jellyfish, also known as white-spotted jellies, can grow up to 17 inches wide. Chris Collins and his wife, who encountered a jellyfish for the first time, had initially thought it was a stingray or a sea turtle.
Other reported sightings are jellyfish that were stranded on beaches. For now, said local authorities, they are still figuring out how many white-spotted jellies are in South Carolina waters.
Invasive White-Spotted Jellies
The invasive species can also damage fishing boats and equipment, especially when there are jellyfish blooms. Similar to algal blooms, jellyfish populations rapidly multiply in warm ocean temperatures and can survive harsh conditions such as lack of oxygen.
Globally, jellyfish blooms have been the result of climate change. Large numbers of native and invasive species can potentially disrupt the balance of marine ecosystems since their main food source are zooplankton, one of the foundations of the underwater food web. Swarms of jellyfish in certain areas leave little available food for marine animals such as fish and crustaceans that depend on plankton as well.
White-spotted jellies have already disrupted the marine ecosystems in the Caribbean Sea, Gulf of Mexico, and the Gulf of California. "In their native waters, they tend to be fist-sized," said Monty Graham from the Dauphin Island Sea Lab. However, in the Gulf of Mexico, they grow as large as dinner plates.
Since 2007, the invasive species have been spotted on the Florida coast and reaching North Carolina beaches. However, the species don't necessarily migrate from the Pacific Ocean to the Atlantic, they hitchhike on the side of ships or fishing boats.
Consequences of Overfishing
Jellyfish can also reach shores from strong tropical storms that carry jellyfish larvae or sea lice. The storms are also a consequence of climate change, shared Jeff Tittel from the environmental organization New Jersey Sierra Club. Jellyfish are also an indicator that ocean temperatures and water quality have gotten worse, said Tittel.
In a study published in the Cell journal Current Biology; jellyfish was discovered to easily overtake areas that are overfished. Along the Angola and Namibia coast, jellyfish populations increased after the collapse of pelagic fish stocks during the 1960s.
Since the 1990s, the continuously increasing population affected fishing nets, spoiled catches, disrupted power stations, and blocked the sediment suction of diamond mines. At the time, researchers estimated "that the biomass of jellyfish was 12.2 million tons."
The dominance of jellyfish in marine ecosystems may lead to irreversible damage, noted the study. "Jellyfish play potentially major controlling roles in marine ecosystems and, in this era of apparent jellyfish ascendancy, marine ecosystem managers and modelers cannot afford to ignore them," concluded the authors.
Check out more news and information on Jellyfish on Science Times.