Lion's Mane Jellyfish
Lion's Mane Jellyfish Facts
| Size | 0.8-15 inches (2-40 cm) |
| Speed | Unknown |
| Weight | 200 pounds (average) |
| Lifespan | 6-12 month |
| Food | Zooplankton, jellyfish, invertebrates, fish, crustaceans |
| Predators | Fish, sea turtles |
| Distribution | Pacific, Atlantic, North Sea, Baltic Sea |
| Habitat | Coast, open sea |
| Class | True jellyfish |
| Order | Semaeostomeae |
| Family | Cepheidae |
| Scientific name | Cyanea capillata |
| Characteristics | Largest and heaviest jellyfish with longest tentacles |
Main Characteristics
The lion's mane jellyfish is the biggest and heaviest jellyfish, boasting the longest tentacles. It is a stinging jellyfish that releases venom through its delicate tentacles. This venom leads to painful welts on the skin that feel similar to burns. It is especially feared in the summer when many people swim in the sea during their vacations. It holds three records: for being the largest jellyfish, the heaviest jellyfish, and the jellyfish with the longest tentacles.
Names
The lion's mane jellyfish is known by several names: arctic red jellyfish, hair jelly, snottie, sea blubber and giant jellyfish.
Records
The Largest Jellyfish
The Arctic lion's mane jellyfish is the largest jellyfish in the world. In 1870, a specimen with a diameter of 7.4 feet (2.28 meters) was discovered.
The Longest Tentacles
The arctic lion's mane jellyfish is not only the largest jellyfish but also has the longest tentacles in the world. They can reach lengths of up to 120 feet (36.5 meters), making them longer than an adult blue whale!
The Heaviest Jellyfish
The lion's mane jellyfish is also the heaviest jellyfish in the world. It can weigh up to 2,200 pounds (one ton).
Distribution and Habitat
The lion's mane jellyfish is typically found in colder waters: in the Atlantic, the Pacific, the North Sea, and the Baltic Sea. It usually stays close to the shore and at depths of 0-65 feet (0-20 meters).
Way of Life
Lion's mane jellyfish are typically solitary creatures. However, in late summer and autumn, they may appear in large groups known as blooms, as ocean currents bring them to the shore – often at tourist hot spots and perfectly timed for the vacation season.
Anatomy and Appearance
Size and Weight
The bell of the lion's mane jellyfish typically measures 0.8-15 inches (2-40 cm) in diameter. In rare instances, it can reach up to 78 inches (200 cm). Generally, the further from the shore, the larger the creatures tend to be. The average weight is around 200 pounds (91 kg).
Color
Young lion's mane jellyfish start off as a light yellow hue. However, as they mature, their color shifts to a darker red.
Tentacles
The lion's mane jellyfish has 70 to 150 long and fine, hair-like tentacles.
Diet
Lion's mane jellyfish are carnivores. They feed on zooplankton, smaller jellyfish, invertebrates, and occasionally on fish and crustaceans.
Behavior
Swimming
Lion's mane jellyfish are carried along by the current.
Hunting
Lions's mane jellyfish hunt by spreading their bell and tentacles while slowly sinking their bodies. Prey that is below gets caught in their tentacles.
Stinging
How Painful Is a Sting?
When the stinging tentacles touch the skin, it is referred to as a sting. Why? Because tiny threads whip out from the stinging cells, penetrate the skin, and inject venom like a needle. When someone touches a lion's mane jellyfish, they first feel a sensation of warmth. However, this quickly turns into a painful burning sensation, as if someone is holding a lighter to the skin.
How Dangerous Is the Lion's Mane Jellyfish?
The sting of a lion's mane jellyfish can be extremely painful and feels similar to a burn. The affected areas become red and swollen. Fortunately, the sting (or stings) from a jellyfish is rarely life-threatening. In most cases, the swelling and pain subside after a few days. This is not the case for those who are allergic or come into contact with a large area of skin with the tentacles. In such instances, dizziness, breathing difficulties, and even cardiac arrest can occur.
What to Do if You See a Lion’s Mane Jellyfish at the Beach
Do not touch it! Even if the jellyfish appears to be dead, its skin and tentacles can still release venom. It’s best to steer clear of it!
How Do You Treat the Stings?
If you get stung by a lion's mane jellyfish, inflammation of the skin will occur. First aid includes pouring vinegar over the skin, specifically where the tentacles are located. The vinegar neutralizes the venom. Therefore, it’s always a good idea to carry a small bottle of inexpensive household vinegar with you. However, it’s better to seek medical help immediately. Ideally, this should be done on-site, through the lifeguard or water rescue team. They know best what to do.
Life Expectancy
The "adult" free-swimming jellyfish live for about 6 to 12 months. As a polyp, they can survive for several years.
Enemies and Threats
Natural Enemies
Even though lion's mane jellyfish can defend themselves well with their venom, they have numerous enemies. Sea birds, larger fish, and turtles find them quite appetizing. In particular, the ocean sunfish and leatherback turtle feed on lion's mane jellyfish.
More and More Lion's Mane Jellyfish
The number of lion's mane jellyfish is on the rise. For various reasons:
Climate Change
Due to climate change, the oceans are getting warmer. Jellyfish thrive in warm water, allowing them to reproduce more rapidly.
Fewer Predators
Lion's mane jellyfish are preyed upon by fish and turtles. However, there are fewer fish because we humans consume too many. Additionally, there are fewer turtles due to pollution, habitat loss, or because they die as bycatch.
Importance for the Ecosystem
Lion's mane jellyfish are both hunters and prey at the same time. They help maintain the balance of plankton in the ecosystem. For seabirds, fish, and turtles, they are an essential food source.
Reproduction
Lion's mane jellyfish develop – like most jellyfish – from a larva into a "polyp" that initially attaches to the sea floor. From this polyp, additional polyps can form together to create a medusa. The term medusa refers to the "adult" jellyfish that float or swim freely in the ocean. They often have a bell-shaped umbrella and long tentacles.
The Lion's Mane Jellyfish Is Related To:
- Fried-Egg Jellyfish
- Helmet Jellyfish
- Moon Jellyfish
Animals in the Same Biome:
- Bar Jack
- Barracuda
- Blue Jellyfish
- Boxfish
- Dolphin
- Fairy Basslet
- Flying Gurnard
- Green Sea Turtle
- Grouper
- Hawksbill Sea Turtle
- Hermit Crab
- Humpback Whale
- Leatherback Sea Turtle
- Loggerhead Sea Turtle
- Moray Eel
- Needlefish
- Ocean Sunfish
- Octopus
- Parrotfish
- Porcupinefish
- Rays
- Remora
- Seadragon
- Sea Urchin
- Sea Walnut
- Sharks
- Spotted Eagle Ray
- Tuna
- Trumpetfish
Sources:
- „Largest jellyfish“ (https://www.guinnessworldrecords.com)
- „Heaviest jellyfish“ (https://www.guinnessworldrecords.com)
- „Pan-Arctic distribution modeling reveals climate-change-driven poleward shifts of major gelatinous zooplankton species“ (https://aslopubs.onlinelibrary.wiley.com)
