Book 4, Question 115
Why Do Caddisfly Larvae Wear Stick Suits?
A caddisfly larva has a soft body. It builds a portable case, like a tiny suit, to hide inside. The suit is a walking cave made of sand, sticks, or stones.
From the book
Page from A Million Whys Book 4
More fun facts
- Caddisfly larvae live in water and look a bit like caterpillars with legs.
- Some make sticky silk from their mouths and glue together stones, leaves or shells to build a hard case.
- The cases can look like tubes made of sand grains, pine needles, sticks or leaves.
- A larva drags its case along the stream bed as it moves.
- Some caddisfly larvae are only a tenth of an inch long, which may make them the world's tiniest builders.
- They can spend up to two years in their cases before becoming flying adults.
- Fish love to eat caddisfly larvae, so the case helps protect them.
Sources: National Park Service, National Park Service, National Geographic
Questions kids ask
What happens to the case when the caddisfly grows up?
After up to two years, the larva becomes a flying adult and leaves the water.