American dipper
A stream-gray songbird that walks along the bottom of cold mountain creeks to hunt, the only songbird in North America that does.
American dipper at a glance
Cinclus mexicanus DIP-er; Cinclus mexicanus is SIN-kluss mek-si-KAN-us
- Type
- Bird · songbird
- Diet
- Insectivore
- Size
- About the size and shape of a robin but chunkier, roughly 5.5 to 7.9 inches (14 to 20 cm) long, with no bright colors at all: slate gray head to tail.
- Lifespan
- Typically 3 to 8 years in the wild, based on banding records.
- Conservation
- Least concern
Eats caddisfly and mayfly larvae, aquatic insects under rocks, small fish, fish eggs, flying insects
It walks and swims along the bottom of a stream, flipping over pebbles with its beak to flush out insect larvae hiding underneath, then swallows them right there underwater.
Should you worry?
None. It is small, shy of people, and busy working the stream. The real caution is streamside footing: a dipper works the same fast, cold water a kid could slip into, so watch your own feet, not the bird.
The bird bobbing on a midstream rock looks like nothing much: slate gray all over, robin-shaped but chunkier, no crest or color to it at all. Then it steps off the rock into the current, and instead of swimming on top the way a duck would, it walks straight down the streambed, wading against water fast enough to knock a kid off their feet, and keeps going until it disappears.
It can do that because of what happens right before it goes under. Scaly flaps seal over its nostrils. A clear inner eyelid slides across each eye, so it can still see clearly through the churn. Its short, stiff wings paddle like flippers while its long claws grip the rocks, and it walks upstream along the bottom for five to fifteen seconds at a stretch, flipping over pebbles with its beak to flush out caddisfly and mayfly larvae hiding underneath. An oversized oil gland has already coated its feathers waterproof, with a layer of down underneath trapping a cushion of warm air, so it comes back up dry against skin that never felt the cold at all.
It builds its nest the same way it lives, right up against the water: a domed clump of moss tucked into a cliff ledge or a bridge support, sometimes behind the curtain of a waterfall itself, with the entrance facing straight out over the current. A stream that can support a dipper year-round is cold, fast, and clean enough to grow the insect life it needs, so the plain gray bird on the rock is also a rough gauge of how healthy that water is. Watch the rock a minute longer. It will step off again.
Did you know?
- A dipper's eyelids are lined with white feathers, so each blink flashes a bright white wink, which biologists think may double as a signal to other dippers over the roar of a rapid.
- It builds its nest so close to the spray of a waterfall that the chicks sometimes fledge straight into the plunge pool below.
- Because it needs cold, clean, fast-moving water full of insect life, a stream with dippers working it is a rough sign that the water itself is in good shape.
Common questions
Can the American dipper really walk underwater?
Yes. It closes flaps over its nostrils, drops a clear extra eyelid to see, and grips the stream bottom with its claws while its short wings paddle, walking against the current to flush out insects.
Why doesn't the dipper get cold in freezing streams?
A big oil gland waterproofs its feathers, and a thick layer of down traps warm air underneath, so cold water barely touches its skin.
What does an American dipper eat?
Mostly insect larvae it finds under streambed rocks, plus small fish, fish eggs, and flying insects snapped up at the surface.
Where would you actually see one?
Standing on a rock in the middle of a fast mountain stream, bobbing up and down, right before it walks or dives in.