Their Stings

All jellyfish sting their prey using nematocysts, also called cnidocysts, stinging structures located in specialized cells called cnidocytes, which are characteristic of all Cnidaria. Contact with a jellyfish tentacle can trigger millions of nematocysts to pierce the skin and inject venom, yet the sting of only some jellyfish species causes an adverse reaction in humans. When a nematocyst is triggered by contact by predator or prey, pressure builds up rapidly inside it up to 2,000 lbs/sq. inch until it bursts open.

A lance inside the nematocyst pierces the victim's skin and poison flows through into the victim. Touching, or being touched by a jellyfish can be very uncomfortable, sometimes requiring medical assistance; sting effects range from no effect to extreme pain to death. Because of the wide variation in response to jellyfish stings, it is wisest not to contact jellyfish with bare skin. Even beached and dying jellyfish can still sting, when touched.

Jellyfish are usually found near the surface of the water during times of diminished light, floating in the water column, or after washing up on the beach. Jellyfish stings are generally accidental - from swimming or wading into a jellyfish or carelessly handling them.

The symptons include:

• An intense, stinging pain, itching, rash, and raised welts.
• The progressive effects of a jellyfish sting may include nausea, vomiting, diarrhea, lymph node swelling, abdominal pain, numbness/tingling, and muscle spasms.
• Severe reactions can cause difficulty breathing, coma, and death.
• A sting from a box jellyfish or other venomous types of jellyfish can cause death in minutes.