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Least Grebes build nests on ponds, dive underwater
by Karen Benson
Nov 09, 2010 | 977 views | 0 0 comments | 4 4 recommendations | email to a friend | print
Why is this frog smiling?
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Why is this bullfrog smiling? Because he lives in a fine, “froggy” pond in northern Bee County! The abundant rain in early September filled up many of our smaller, shallower ponds. Indian summer’s lingering warmth and sunshine allowed algae and submerged water plants to thrive. The ponds became magnets for several kinds of frogs. They croaked, they attracted mates, they laid eggs. When the eggs hatched there was plenty of vegetation for the tadpoles to eat, and now these ponds are full of frogs!

A fine pond for frogs in South Texas is also a splendid place for one of our native bird specialties. The small, pond-dwelling Least Grebe may at first appear to be a duck. Closer examination reveals a thin, pointed, bill, golden eyes and an almost tailless body. And Least Grebes only weigh about four ounces, less than half that of our smallest ducks.

Grebes in general are considered to be a rather primitive family of birds. This is why they are found near the front of our bird books, right next to loons. Good bird field guides are organized “phylogenetically” which means according to the birds’ scientific classification.

Grebes’ skeletal structure is similar to loons and penguins in that the legs are set well back on the body. This means the birds are excellent swimmers. They are propelled by their feet almost like a boat is propelled by its rear-mounted motor. It also means that grebes cannot walk well on land. They are top-heavy and usually fall forward on their bellies and use their legs to scoot along. In fact, walking is so awkward for grebes, that they almost never do it. They prefer to stay in the water.

They even build their nests on the water. Grebe nests are floating mounds of aquatic vegetation, sometimes anchored to reeds but sometimes not. Rotting vegetation is usually used. As any backyard composter knows, rotting vegetation generates heat. And that helps incubate the eggs!

If you disturb grebes, they usually dive and swim away underwater. They can stay submerged about 15 seconds. They may re-emerge yards away from where they dove. Also, they can sink slowly by emptying their air sacs and flattening their plumage. It is odd to see a bird sink.

Since they are so adapted to water, you might think that grebes cannot fly, but they can. They must flap their small wings strenuously and patter their feet across the surface of the water to get airborne. I confess that I have never seen a Least Grebe fly. But they have to fly in order to get to a new pond, especially if the old one is drying up. These flights presumably take place at night.

Our favorite pond in northern Bee County has not just one Least Grebe, but an entire family. The mated pair built a nest and hatched out three babies. Grebe chicks are strikingly marked with patches of bare orange skin and black-and-white stripes. The chicks can swim right after they hatch. They follow the adults around until they get tired. They then climb on momma’s or daddy’s back for a ride. Both parents feed them aquatic bugs such as dragonfly nymphs, water beetles, and small surface insects. Sometimes tadpoles are taken as food, but don’t tell the frogs!

Another specialization in grebes is the habit of eating feathers. I have heard that they eat their own feathers, but it seems likely any small feather they find could be eaten. Why eat feathers? Feathers help the grebe’s stomach form a pellet of indigestible insect parts. This pellet is then coughed up. Owls and hawks eliminate bones, feathers and fur that are in their diets the same way.

Grebe feathers are especially fine and soft. The feathers are very close together as well, making the plumage thick and waterproof. In the 19th century, breast pelts of grebes were used to make ladies’ muffs, capes and hats. These soft, feathery pelts were called “grebe fur.” It is said that in South America, the local Indians harvested grebe pelts to use as saddle blankets. Fortunately for the grebes, those days are over. It is unlikely that our tiny Least Grebes were ever hunted for these purposes.

Go out and check your local ponds. Grebes and frogs can breed here almost all year long. If you think you see a grebe and it dives, count to 15, slowly. It should come back up. But be patient. It may hide. Meanwhile, enjoy the frogs and toads (and dragonflies) that also like these ponds. South Texas ponds are nice enough to make even a frog “green with envy!”

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