Giant Jellyfish

June 6th, 2007

The jellyfish are invading the waters of the Pacific Northwest. Not the life-threatening type, like the box jellyfish, but still venomous enough to provide an unpleasant sting on the upper lip as you run into a translucent tentacle during your safety stop. Though the tiny box jellyfish is one of the most deadly in the world, the cool waters of the Pacific Northwest are home to some of the largest jellyfish on Earth.

The Egg-yolk jellyfish (phacellophora camtschatica) is a species of jelly we typically see around Puget Sound and the waters of British Columbia. It can reach over two feet in diameter with tentacles reaching up to 20 feet in length. Divers can easily get tangled in these tentacles if the visibility is poor or if they’re not paying attention to where they’re going. The translucent tentacles fire venomous nematocysts that act as miniature poison harpoons, lodging themselves into your skin and releasing neurotoxins that are designed to paralyze mobile prey. The action of a nematocyst firing is the fastest occurring biological phenomenon known to man. Here is a video I shot of a large egg yolk jelly, taken during a dive trip to Porpoise Bay, BC.

The Lion’s mane jellyfish is the largest known form of jellyfish - a creature that can grow to over 7 feet in diameter and its tentacles can stretch to a whopping 120 feet in length. The arctic versions are the largest/longest, with the sizes shrinking as the latitudes reach further toward the equator. The largest ones I’ve seen here in our waters have tentacles in the 25 - 30 foot range, still very long and terribly hard to see in poor visibility. The easiest way to differentiate between an egg yolk jellyfish and a lion’s mane, is by the number of clusters - or nodes - of tentacles originating from the bell of the jellyfish. The egg yolk has 16 and the lion’s mane has half as many.

With these monsters already in our waters, I’m glad I don’t have to have a run in with Willy Volk’s Uber Jellyfish, shown below.

Entry Filed under: Puget Sound, SCUBA