Giant phantom jelly (Stygiomedusa gigantea) is not just another jellyfish; it’s a mesmerizing marvel of the ocean that can reach lengths of up to 33 feet (10 meters)! Found in every ocean around the world—except the icy Arctic—these majestic creatures thrive in the deep, where few humans dare to journey.

What do they eat?

Well, the giant phantom jelly is a predator of the underwater world, primarily feeding on plankton and small fish. How does it capture its prey? Unlike your typical jellyfish that rely on stinging tentacles, the giant phantom jelly employs a fascinating technique—it wraps its long, ribbon-like arms around unsuspecting food and then hoists them right into its mouth. This unique feeding behavior sets it apart from many of its gelatinous relatives.

Why is it so extraordinary?

When we think of giant ocean creatures, most of us may conjure images of massive whales or fierce sharks. Yet, the giant phantom jelly is among the largest invertebrate predators lurking in the depths. The first recorded specimen was captured in 1899 and described to the world in 1910, but since then, sightings have been incredibly rare—around just 120 times! They typically dwell at monstrous depths of up to 22,000 feet (6,700 meters), where the crushing pressures mean their bodies are designed to be compressible and squashable for survival.

In a groundbreaking revelation, researchers observed these elusive jellies during submersible expeditions in Antarctica during 2022. For the first time, they documented instances of giant phantom jellies swimming at relatively shallow depths of between 260 to 920 feet (80 to 280 meters). This remarkable discovery suggests a correlation between seasonal changes in sunlight and the rise of prey to shallower depths, possibly enticing the jellies closer to the surface.

And here’s the jaw-dropping part: the giant phantom jelly is viviparous, which means they give birth to live young! The young jellies develop inside the mother, only to swim out through her mouth, a sight that’s as astonishing as it is rare.

But wait, there's more! When exposed to visible light, these jellies emit a faint orange-red bioluminescent glow. The exact purpose of this glowing feature remains a mystery. Researchers hypothesize it could play a role in communication, evading predators, or attracting potential mates. However, due to their habitat in the deep ocean, where red light barely penetrates, this enigmatic glow is likely a survival tactic, helping them remain hidden from both predators and prey.

As more expeditions and studies are conducted, who knows what further secrets about the giant phantom jelly and its elusive lifestyle may be discovered? One thing is certain: the depths of our oceans harbor wonders that continue to astound and captivate us!