A very special and unique place.

Mystery Of The Red-Eyed Bird: A Million Eared Grebes
By David Carle, Park Ranger, Mono Lake Tufa State Reserve

They come in the gloom of the night when no human eyes are watching. Silently, dark shapes with red eyes descend from the sky. Thousands upon thousands blanket the black surface of the lake. They keep on coming. Alfred Hitchcock never dared dream of a bird invasion of such scale. Soon three-quarters of a million avian invaders are here. We call them eared grebes because of a pair of feathered crests which decorate their heads in breeding season.

An autumn dawn at Mono Lake allows human visitors their first look at the nighttime arrivals. At first, all you may notice are lots of dark dots out on the water. Look through binoculars and you will see that they are small, duck-like birds. Then begin to focus across mile after mile of the surface of this big lake. From the south shore it is nine miles across. You may see eared grebes crowding the water through that entire distance.

Eight hundred thousand eared grebes come to Mono Lake in the fall. That is one heck of a lot of birds of just one type. We do not really know how many eared grebes there are in the world. Some guess that one-quarter of the entire species is here on this lake, all at once.

They come here from nesting grounds in Canada. They will stay at Mono Lake until the food supply disappears, as brine shrimp die off in the cold weather of November or December. Then the grebes head for Central America to overwinter. At least, we know they end up down there. No one ever witnesses their nighttime arrivals and departures.

Grebes seem mysterious in other ways. Their looks are rather strange. They have a dark back, whitish underparts (which you can see best along the throat), a small, light cheek-patch, and those unusual red eyes. They spend a good part of their life under water.

Eared grebes have lobed toes to help them swim. Not webbed, like ducks, but more as if you had a flap of tissue sticking out from either side of your fingers. But the real strange aspect of their body design is the location of their legs.

Think of a penguin. Its legs are at one end of its body, so it stands upright on land, sort of like a human. Underwater, those legs become propellers, located at the back end of the bird, perfectly placed to shove them along most efficiently. Eared grebes have "propeller-legs" at their back ends too, but they are not designed as well as a penguin's. They swim great underwater, but they cannot stand up on land.

If you ever see an eared grebe on solid ground, something is wrong. Every so often someone finds one of these birds and brings it to us. Who knows why or how they came to be on land, but once there, they were helpless to take off again. Did I mention that eared grebes seem to be weak fliers? At least they really have to work to take off from the water. They cannot get moving at all from land, can't even stand upright. The concerned people think the bird must be sick, since it sits so quietly. Every time this has happened, we have taken the grebe to the lake and, happily, it has sped off across the water, until it was out far enough to dive.

They can stay underwater for a long time. It's a way to escape, but is used more when they are hungry. Eared grebes dive for brine shrimp at Mono Lake. They seem to spend almost as much time underwater as on top of it. If you have ever gone swimming in the harsh alkaline waters of this lake, you may remember how it can sting if you get the water in your eyes. Come to think of it, maybe that's why the grebes have red eyes. You'd have red eyes too if you dove under Mono Lake all day with your eyes open.

Actually, there is a theory that the red color helps the grebes to see better in the underwater gloom. It has something to do with wavelengths and penetrability through the water. Think of amber foglights on a car — same general idea.

The most impressive thing of all, the thing everyone keeps coming back to when they talk about these birds, is their number. Up to 800,000 of them are here in the fall. Along with the other fall migrants and birds that have been here all summer, the grebes help make autumn the "birdiest" time of year at Mono Lake.

Sometimes they mass so closely together that it seems like you could walk across the lake on the back of grebes. Think about that number — 800,000 — for a moment. If each grebe takes up about 12 inches, and they sat end to end, they would extend 150 miles! Good thing Mono Lake has about 60 square miles of surface where they can spread out.

Their combined weight totals somewhere in the vicinity of 100,000 pounds. Who cares, you ask? The amazing thing about their weight is that they will double it here in just 30 days, gorging themselves on brine shrimp. That's a clue as to just how many shrimp the lake produces (millions of pounds of the tiny little creatures!).

The irony of all of this is that Mono Lake is still referred to by some misinformed writers as a "dead sea." In truth, it is a super-productive ecosystem, supporting far more life than the fresh-water lakes of this area — relative deserts by comparison.

I am impressed by eared grebes. They help to make Mono Lake unique. They remind us of their importance of this place to other sites thousands of miles away in Canada and Central America.

But I have to admit that I don't relate well to them. They fly by night. They spend a lot of time underwater where I can't see what they are up to. They are almost always silent. They hang around enormous crowds that only a New Yorker could love.

Some mysterious night, late in the fall, they will startle us again by disappearing into the gloom. Soon after, somewhere in Central America, dark, silent, red-eyed figures will descend from the sky.

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