Expert raises alarm after once-in-a-lifetime event off the coast of Tasmania: 'Something is wrong'

In late January, onlookers flocked to Tasmania's Storm Bay to witness a rare and magical event: swarms of moon jellyfish swimming in bioluminescent algae. 

While the glowing shoreline was undoubtedly beautiful, biologists say it's a warning sign that ocean ecosystems are out of balance.

What's happening?

As the Guardian reported, huge numbers of jellyfish and algae have been taking over the bay recently. Lisa-ann Gershwin, a biologist and jellyfish specialist, said the surge in population growth was "unprecedented" and had increased significantly over the past few weeks. 

She first observed the dazzling display in early December when a bloom of small jellyfish appeared in the bay and halfway up Tasmania's east coast. When the jellyfish died, their decomposing bodies left behind tons of nutrients for the bioluminescent algae to feed on. 

Not knowing how long the jellyfish and algae would stick around, Gershwin offered "glow tours" so people could see the possibly once-in-a-lifetime spectacle. The strange event may have captivated tourists, but Gershwin said frequent jellyfish blooms signal that "something is wrong in the ocean."

"Each of them is a visible indicator of this and also a driver of more damage. But combined, one after the other, after the other, it's insane," she added.

Why are the jellyfish blooms concerning?

While jellyfish blooms are a natural phenomenon and occur when environmental conditions are right for them to reproduce, warmer ocean temperatures caused by the changing climate have made them more common. Gershwin explained that if these blooms occur too often, they can disrupt the marine food chain and ecosystems, which could have long-term impacts.

"What they do is they eat the eggs and larvae of other species, so that those species don't have the next generation … the jellyfish just eat them all," she told the Guardian.

The small jellyfish-like creatures, called salps, also eat huge amounts of phytoplankton, which other animals such as zooplankton, crustaceans, and small fish depend on to survive. 

Do you worry about air pollution in your town? All the time Often Only sometimes Never Click your choice to see results and speak your mind.

Bioluminescent algae also feast on phytoplankton, which can cause oxygen depletion if their population drops significantly since they produce about half of the Earth's oxygen, according to the Columbia Climate School. 

If the jellyfish blooms keep happening, it may eventually affect the populations of fish and shellfish that humans eat. 

In 2007, one jellyfish invasion killed more than 100,000 farmed salmon in Northern Ireland, devastating the country's fishing industry, as BBC News reported. Some scientists and chefs believe eating them could be a viable solution, though they acknowledge that jellyfish won't appeal to most people's palates. 

As for the jellyfish swarms in Tasmania, Gershwin said how long they will continue depends on food availability and weather conditions. 

"Nobody knows, we are literally in unprecedented circumstances," she told the Guardian.

What can be done to help?

As scientists told BBC, adding jellyfish to our dinner plates could help bring marine ecosystems back in balance and prevent huge losses to the fishing industry, but that's unlikely to catch on anytime soon. 

Since the uptick in jellyfish blooms is caused partially by rising ocean temperatures and excess nutrients seeping into the oceans from waste and fertilizer runoff, we can help control their population by keeping our oceans healthy. 

Switching to energy-efficient appliances and clean sources of energy, such as wind and solar, will help cool the planet and reduce ocean temperatures, making jellyfish less likely to overproduce. 

Jellyfish thrive in low-oxygen environments, so managing nutrient runoff from farms and wastewater treatment plants will keep oxygen levels in the oceans stable and prevent the conditions that cause jellyfish and algal blooms. 

Join our free newsletter for good news and useful tips, and don't miss this cool list of easy ways to help yourself while helping the planet.