World-leading jellyfish expert Dr Lisa-ann Gershwin says research shows jellyfish influxes or blooms are increasing in disturbed habitats around the globe.
A trend referred to as the "jellification" of the ocean but some say the jellyfish invasion can get exaggerated.
On the North-West Coast of Tasmania recently the Devonport Surf Life Saving Club alerted swimmers to an influx of jellyfish with the bluebottles that blew in capable of delivering a nasty sting. Bluebottles are becoming a more regular sight in Tasmania due to warming waters. The East Coast is considered a global warming hotspot, with waters heating up to four times the global average.
However, Dr Gershwin, of Hobart, said she was a lot more concerned about naturally-occurring jellyfish blooms in North-West Tasmania because of a couple of known factors thrown into the mix.
"It's far scarier than (blow-in) bluebottles as painful as the sting is," she said.
Dr Gershwin said the ingredients were all there for jellyfish blooms to take over.
"It's a recipe for disaster in the North-West," she said.
"We can see jellyfish are increasing any place where you have one or more disturbances. Whether it's warming water, overfishing, pollution including nutrient pollution which they really like or a change to the habitat that stresses out the fish, crustaceans, and mollusks. The winners are the jellyfish and in some cases, one impact is enough to see more jellyfish, but in many cases, it takes more than one impact.
"I've had my eye on the North-West Coast because of a worrying factor that's going on there.
"Jellyfish like warming and with the potential increase in salmon farming that also really concerns me because of what we are seeing in southern waters where we have aquaculture going on, and we see substantial increases in jellyfish that appear to be related to this."
Dr Gershwin said the combination of warming waters and additional nutrients in the water from aquaculture was a concern but was not getting studied.
"Either of those is sufficient to stimulate jellyfish, but in combination, it makes me very worried," she said.
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The jellyfish have a real advantage with lots of tentacles that are food capturing devices, and they're feeding 24-hours-a-day, she said.
"When you look at areas with jellyfish blooms, there is nothing else in the water. They dominate the entire ecosystem," Dr Gershwin said.
One of the best-studied examples was the Black Sea in Eastern Europe. "A jellyfish native to America was accidentally introduced in ballast water into the Black Sea, and had no native predator. Within a few years, it expanded into such unbelievable numbers it wiped out the entire Black Sea ecosystem.
"You don't need for it to be an introduced jellyfish to have a problem jellyfish. What you need is the context for it to get out of hand, such as warming water and excess nutrients, which is a recipe for disaster in the North-West."
Dr Gershwin said what caused her anxiety levels to go up was nobody was studying what's happening with the jellyfish in the North-West. "You've got this context for a tremendous rise in jellyfish and the thing about the Bass Strait in large part it holds the water in one place so functionally it's like the Black Sea. You've got the same context for what we've seen in damaged places, and I see this could go so badly, but we have no data," she said. "We should be asking for the data.
"The government will throw research funding at it when there's a complete collapse of local fish populations, but it's too late by then."
Aquaculture Minister Guy Barnett was asked for comment.
A Department of Primary Industries, Parks, Water and Environment spokesperson said "jellyfish blooms can occur for a variety of natural reasons." "To the Department's knowledge, assertions that jellyfish blooms in Tasmania are increasing in areas of finfish farming operations has not been substantiated by peer-reviewed scientific literature," the spokesperson said
Dr Gershwin said with invasive jellyfish blooms you get a double whammy in warming water it amps up their metabolism, so they breed more, grow faster, eat more and live longer.
"They become like super jellyfish with warmer water, and when you get an out of control bloom, the density of jellyfish is gobsmacking. The current science on this is that there is a very strong pattern of an increase in jellyfish in disturbed areas. Without actual data, I can't say we're at the edge of a crisis because I don't know where we are along that pathway but I can say when I look at these triggers I know from mounds of research worldwide and I look at the North-West I genuinely believe if you add in more nutrients, it will tip.
"I think it's a really serious issue, and we need to be safeguarding from a collapse but we need the data to know how fast things are advancing."
She said numerous jellyfish species native to the North-West were known to bloom into problematic super abundances and cause problems. "They already exist in the North-West Coast naturally. All they need is a trigger to take over," she said.
"The bolinopsis jellyfish is closely related to the species that crashed the Black Sea but is a more superior pest. It's causing tremendous problems in Japan, and it's occurring naturally in the North-West. If you want to mess up your ecosystem, provoke bolinopsis into super abundances. We also have the aurelia or moon jellyfish causing problems for the salmon industry in the south. It's the pest causing massive losses for the industry.
"At the very least, if the salmon industry is hoping to expand, we need the baseline data to measure changes in the ecosystem. It's common sense."
The challenge for Tasmania's billion dollar salmon farming industry was to grow sustainably, with expansion plans in the North-West off Stanley and a new farm on the east coast.
The Tasmanian Salmonid Growers Association was contacted.
Check out Dr Gershwin's popular jellyfish app: https://thejellyfishapp.com/