Jellyfish blooms can swamp entire ecosystems, but there's growing interest in their culinary potential. But could this really solve the ocean's problems?
It has been difficult to predict exactly how jellyfish will behave in a warmer climate, because there is not a lot of historical data on them, explains Monty Graham, director of the Florida Institute of Oceanography in St. Petersburg. "A few decades ago, no-one was really paying attention to jellyfish," he says. "But jellyfish are very sensitive to climate cycles. And so by extension they'll be very sensitive to long-term climate changes as well."
Historically, jellyfish have historically been kept in check by marine predators, such as seabirds, sea turtles, fish and whales. However, their predator populations have been dwindling, thanks to a combination of factors including overfishing, climate change, pollution, and habitat loss.
Across the globe, jellyfish outbreaks have been wreaking havoc on fish populations, and the fishing and tourism industries, to name a few. In 2007, the entire Irish salmon industry was wiped out by a plague of millions of jellyfish covering 10 square miles (26 sq km) and 35 ft (10.7m) deep. They swarmed the cages of farmed salmon, killing more than 100,000 fish.
In Japan, fishermen have seen extraordinary blooms of Nomura's jellyfish annually since 2002. The species grow up to 6.5ft (2m) in diameter and weigh as much as 485 lbs (220kg). They have devastated coastal livelihoods, costing the Japanese fishing industry billions of yen. "Some areas are going to experience more jellyfish populations, higher numbers, and prolonged blooms, especially if we continue to push down on the fisheries that are in the ecosystem," Graham says.
Just eat them
The sea provides a significant proportion of the protein humanity consumes. In 2020, fisheries captured around 112 million tonnes of aquatic organisms according to the US Food and Agriculture Organisation (FAO). As global demand for food rises, serious questions remain about our food supplies.
Some scientists, such as Piraino, believe one solution is broadening our palates. He suggests that since the world is in urgent need of sustainable food resources, one way to achieve this is to attempt to integrate new foods into traditional recipes and local cuisine. "Maybe the time has come to add a new item to our own menu: jellyfish," says Piraino.
Jellyfish is already eaten across Asia, but it is still a rarity to find it in a Western restaurant. In China, jellyfish have been eaten for more than 1,000 years, with jellyfish salad a popular delicacy. Not only are they high in protein, but the microalgae inside the cells of some jellyfish are rich in fatty acids. The practice has not quite caught on in the Western world, but some restaurants are pushing their diners to embrace the unknown.
The chef's pass at Benu, San Francisco, is like most others in the city: a calm anticipation as the crescendo builds towards the impending chaos of service, while the chatter of diners wafts into the kitchen. But unlike most other fine dining establishments, there’s something special on the menu – and that's jellyfish.
On one show-stopping dish, the jellyfish graces the plate delicately wrapped around a single shrimp, sporting a caviar and horseradish coat. It's a "very approachable way" to enjoy jellyfish, says Corey Lee, founder of Benu. Lee, who hails from South Korea, grew up eating jellyfish. He says it was something he wanted to share with his diners that was "delicious and underappreciated". It’s been served in various forms since Lee opened the three-Michelin-star restaurant in 2010. Another appearance is live and fresh in a beef consommé. "The oceany flavour provides a sharp contrast and salinity to the rich and gelatinous soup, while its wobbly texture evokes the texture of long-cooked beef tendon," Lee explains.
However, despite their appeal to adventurous Western diners, jellyfish are not a viable straight substitution for fish, or other sources of protein, when considering what is best for the environment. It’s true that expanding our palates to include alternative sources of protein is vital in helping mitigate climate change, but jellyfish may not be the answer.
For one thing, jellyfish are 95% water, with the remaining 5% containing the nutritious essentials. Their nutrition to mass proportions means they’re a fairly inefficient source of protein. "They’re very high effort to eat," says Graham. "There’s a lot of energy expended in the process just because they're so watery. They’re also not all great to eat."