Halloween quiz: poisonous vs. venomous sea creatures

With the celebration of ghosts, goblins and things that go bump in the night nearly here, there’s no better time to talk about poisonous and venomous critters at the Seattle Aquarium. Do you know the difference between poison and venom? Most people associate venom with snakes, which provides a good hint about the correct answer to our question: venom is always delivered via a wound (a sting or a bite, for example), while poison is ingested, inhaled or absorbed through the skin.

Both poison and venom contain both contain toxins, which sea creatures use to catch prey and/or defend themselves. Toxins are molecules, often in a cocktail of combinations that may affect the nervous system (neurotoxins), overstimulate the immune system (allergens) or even eat away at the flesh (proteolytic toxins)!

Do you know what animals at the Seattle Aquarium are poisonous and which are venomous? Test your knowledge below!

Sea anemone:

Sea anemone





Venomous. A rockfish’s dorsal, pelvic and anal spines all contain a mild venom.


Sea urchins:

Sea urchins

Gotcha! Local sea urchins, like those on exhibit at the Aquarium, have long, sharp spines but don’t produce toxins. Some tropical species of sea urchins are venomous, however.






Cabezon eggs:

Cabezon eggs

Poisonous. If you ate cabezon eggs, although we can’t imagine why you’d want to, you could experience nausea, diarrhea or—at the extreme end—go into a coma. It’s thought that the poison in these eggs may be an adaptation to provide protection after they’re laid, typically in shallow water.




Venomous—but not poisonous, so this fish is actually recommended for human consumption in many areas.




Venomous. An octopus bites with its beak, then injects venom into the wound via its saliva.


Puffer fish:

Puffer fish

Poisonous. Tetrodotoxin is what makes the puffer fish poisonous—it’s the same toxin found in blue-ringed octopuses, which are venomous (one of the marine world’s most venomous animals, in fact, and NOT on display at the Seattle Aquarium!).




Venomous. Moon jellies, like those found in the Ring of Life exhibit at the Seattle Aquarium, deliver a mild sting to humans that results in little to no reaction.


Moray eel:

Moray eel

Gotcha again! Moray eels can deliver a very painful bite but aren’t venomous.


Get to know more about these animals on your next visit to the Seattle Aquarium!

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