Why is its upward side blue?

To blend with the water from above

What does it do with its prey's stinging cells?

Stores them for its own defense

When do people often see them?

When winds wash them onto beaches

Blue Dragon Sea Slug Quiz: Glaucus Floating on the Ocean

This blue dragon sea slug quiz floats on the ocean surface with Glaucus atlanticus. Play 10 interactive questions on swallowing an air bubble to float, blue countershading facing the sky, feeding on the Portuguese man o' war, storing stolen stinging cells, a sting that can hurt people, tiny size, washing up on beaches and why it is a type of nudibranch.

Start Blue Dragon Sea Slug Quiz

🎯 Daily Trivia Challenge • 🧠 10 Questions • ⏱️ 150 Seconds

Question 1 / 10 Time: 150s

Name
What is the blue dragon's scientific name?
Group
What kind of animal is it?
Float
How does it stay on the surface?
Upside
How does it float?
Color
Why is its upward side blue?
Prey
What does it eat?
Steal
What does it do with its prey's stinging cells?
Sting
Can a blue dragon sting people?
Size
About how big is a blue dragon?
Beach
When do people often see them?

Explanations: answer key for all 10 questions

Q1: What is the blue dragon's scientific name?
Answer: Glaucus atlanticus
It is a sea slug.
Q2: What kind of animal is it?
Answer: A nudibranch sea slug
It is a mollusk.
Q3: How does it stay on the surface?
Answer: By swallowing an air bubble
The bubble sits in its stomach.
Q4: How does it float?
Answer: Upside down
Its blue side faces the sky.
Q5: Why is its upward side blue?
Answer: To blend with the water from above
This is countershading.
Q6: What does it eat?
Answer: Portuguese man o' war
It is immune to the stings.
Q7: What does it do with its prey's stinging cells?
Answer: Stores them for its own defense
They collect in its fingerlike tips.
Q8: Can a blue dragon sting people?
Answer: Yes, it can be painful
Do not touch beached ones.
Q9: About how big is a blue dragon?
Answer: A few centimeters
It is tiny.
Q10: When do people often see them?
Answer: When winds wash them onto beaches
They drift with currents.

A Tiny Dragon on the Waves

The blue dragon, Glaucus atlanticus, is a nudibranch, a type of sea slug, only a few centimeters long. It floats on the ocean surface by swallowing an air bubble that sits in its stomach, drifting upside down with its blue side facing the sky.

That blue side blends with the water when seen from above, while its silver back blends with the bright surface when seen from below, a camouflage called countershading. Blue dragons feed on the Portuguese man o' war and other floating stingers, unharmed by their stings.

They store the stolen stinging cells in fingerlike tips and use them for defense, so a blue dragon can give a painful sting. Winds sometimes wash them onto beaches, and people are warned not to touch them.

What This Quiz Teaches

Ocean fans will enjoy these questions.

What the blue dragon is
How it floats
Why it is blue
What it eats
Why it can sting

Did You Know?

They are found in warm oceans worldwide.
Each one is both male and female.
They often appear in groups.
Photos of them go viral.
Their eggs are laid on floating debris.