The Dipper - Plain but not ordinary

Dippers perch almost exclusively on rocks in or by the water; they rarely perch in trees. The stream is flowing just below this dipper.

While standing at the edge of a beaver pond watching for any clue as to which fly I should use, a movement out of the corner of my eye caught my attention. Glancing down, I noticed a plain, ordinary-looking grey bird walking on the shoreline near my feet. Wandering aimlessly, it eventually left the shore for the pond. But as the bird entered the water, I did a double take. For now this bird was walking along the bottom of the pond, just as it had on shore! Through the clear water, I could see the bird occasionally peck here and there as it continued its submerged stroll. After about forty-five seconds, the bird walked back out on the shore--completely dry. It hopped up on a rock, bobbed up and down a few times, and then flew downstream.

That encounter with the American Dipper nearly three decades ago sparked an interest in me to learn more about this strange bird. Since then, I have come to realize that the Cinclus mexicanus may well be one of the most fascinating and yet least known birds in the Colorado Rockies.

A dipper probing for aquatic insects.

One of a kind

Dippers are aquatic birds. What makes this so unusual is that they are not waterfowl. They are songbirds. Their close cousins include wrens, robins, and chickadees. In fact, dippers are the only aquatic songbirds. While they may appear drab, plain, and ordinary, a closer look reveals they are highly specialized for life in mountain streams. No other birds, including waterfowl, are capable of surviving where the dipper thrives. Dippers are truly one of a kind.

What’s in a name?

The dipper gets its name from its habit of perching on a rock and bobbing up and down repeatedly. Just why dippers do this remains a mystery. It is not related to mating rituals, territory disputes, or social interaction. Maybe it’s just fun.

Note insect in beak.

Aquatic diet

Dippers feed solely on aquatic life. They eat caddisfly larvae, mosquito larvae, various nymphs, andoccasionally small fish. Dippers often feed by walking along the bottom of the stream, probing for food with their beak. Whether in fast riffles or deep pools, their strong feet grip the bottom preventing them from being washed downstream or floating to the surface. In larger pools, they may float like ducks and occasionally dive for a meal.

One of the most spectacular and surprising sights is to see a dipper fly into the rapids and pop out a moment later some distance upstream with an insect in its mouth. The dipper is actually able to swim upstream underwater using a flying motion against very strong currents! .

Committed to water

Seasonal drop in water levels leaves this used nest dry and brown. During the nesting season they are usually green.

Dippers spend all their lives in, on, or near the water of clear mountain streams. When traveling, they always fly just above the water, following the path of the stream, even if it would be shorter to cut across a bend. Their globe-shaped nests, made of moss and mud on the side of the stream’s bank, blend in so well with the surrounding vegetation that they are nearly impossible to see unless a dipper is caught going in or out.

When winter comes, the dipper does not head south like many songbirds. Instead, it stays in its mile-long territory as long as there is running water. If the stream freezes over completely, it will move downstream just far enough to find open water again.

Life in the fast, cold, and wet lane

How is the dipper able to thrive in a habitat where other birds could not survive? There is more to this plain, grey bird than meets the eye. As might be expected, the dipper has some unique adaptations that allow it to pursue life in a niche not available to other birds:

I see you, too!

Dippers on-line?

Since their diet is very similar to that of trout, I must wonder if anyone has ever caught a dipper while fly-fishing. Once, while fishing on a small stream, I came upon a tree in which someone’s line had become entangled in the highest branches and apparently snapped. The fly had been blowing out from the tree in the breeze and a flycatcher had caught the fly in its beak. The bird hung from the tree, nearly exhausted. As I pondered how to reach the bird, it finally managed to free itself and flew off. None of the “you won’t believe what I caught” fishing tales I have heard, though, involve dippers.

The cost of specialization

There is no doubt that the dipper has benefited from the popularity of trout fishing. Since trout and dippers share the same habitat, any efforts to preserve prime trout streams also help secure the future of the dipper. Like most highly specialized organisms, the dipper is more extinction-prone than non-specialized organisms. The dipper, so well suited for life in a mountain stream, could never adapt to a different habitat. The fossil record has many examples of creatures that were wonderfully adapted for a specific habitat…and then the environment changed! This is the cost of specialization. But as long as mountain stream habitat is available, the dipper will continue to thrive as one of the most fascinating and unusual songbirds to be found.

This summer, when you fish or hike along a mountain stream, keep your eye out for a plain, grey bird perched on a rock in the middle of the water. Much of its time will be spent preening its feathers. Look it right in the eye and you will see a white flash every time it blinks its third eyelid. Watch long enough, and you will no doubt see it bob up and down. You might even see it take an underwater walk. If you are patient, there is a good chance you will see it fly into the rapids, disappear momentarily, and then emerge on wing, perfectly dry, further upstream. There is nothing plain and ordinary about that.

The Dipper: Plain, yes, but not so ordinary