Facts about Birds and Eggs


The Ostrich

An ostrich egg, at 3.3 pounds is the largest single cell that exists today on our planet. It's also the largest egg, and it looks about the size of a medium cantaloupe. (Some of the dinosaurs had larger eggs. There's a dinosaur egg in the American Museum of Natural History in New York that's about the size of basketball.) For comparison, the smallest bird egg is the bee hummingbird. You could put 4700 bee hummingbird eggs inside one ostrich egg. The bee hummingbird egg is the size of a small pea and weighs .02 ounces.

Carving an ostrich egg is difficult and wears out the drills rapidly. An ostrich egg shell has to be tough enough for a 300 pound bird to sit on it. I've seen pictures of an adult in South Africa standing on an unhatched egg.

The ostrich hen will typically lay 10 eggs, but some productive hens will lay more. The hens will often lay their eggs in the same nest as other hens, with the result that you can find as many as 50 eggs in single a nest.

Ostriches are native to South Africa, but you can find them everywhere from Texas to Beijing. Farmers grow them for their hides, feathers, meat, eggs, and other byproducts. They're the world's largest living bird.

By the way, would you ever have guessed that it was the automobile that saved ostriches from going extinct in the wild? Back at the time of the American Revolution, a French Queen, Marie Antoinette made a casual gesture that consigned thousands of species of beautiful birds to extinction. She took a feather from a decorative stand and placed it in her coiffeur. Instantly wearing feathers became a fashion rage. Ladies throughout the world vied for the most elaborate feathers they could find for their hairdos and hats. Hunting wild birds for their feathers became a large scale enterprise throughout the world. Species after species was hunted to extinction. The ostrich feathers were particular prized because they have such a "floaty" quality to them. The ostriches were on the verge of extinction in the wild when an unexpected savior occurred on the scene: the automobile. When milady was on her horse, sidesaddle, gracefully cantering across the fields, her ostrich plume looked lovely. On the other hand, when she was in an open automobile speeding along at 40 miles per hour, the ostrich plume was a disaster. Ostrich feathers went out of style, and records that still exist in the National Agricultural Library show that the trade in ostrich feathers virtually ceased in 1913.

The Emu

You can tell an emu egg by it's large size and greenish black color. It's about the size of a small grapefruit and in shape, it makes you think of a football with rounded ends. The emu egg, by the way, comes in several shades of greenish black. It can be fairly light to almost black. I've seen one that was actually more blue than green.

The emu is a smaller cousin of the ostrich and you can find them in Australia. It stands about six feet tall and weighs around 150 pounds. It's being grown for meat in this country. I have a friend who grows them and she says that some can lay as many as 47 eggs, while others lay only one or two.

The emu has a really neat defense mechanism against its predators. An emu can only run at about 35 miles per hour, while some of its predators -- they're cats-- can run at close to double that speed. Nevertheless, the emus still survive. A cat may be chasing an emu and gaining on it. The emu can't escape by flying, since no bird weighing over 35 pounds can fly. Instead, it races along with it's giant 9 foot long strides. As the cat is bounding full speed after it and just about to catch it, the emu, still running along at top speed, will raise one of its little stubby wings towards the sky and point the other towards the earth. This makes the emu swivel around almost 180 degrees, still at top speed, and it takes off in a different direction. The cat can't turn this quickly and its momentum will keep it going for 30 or so yards, by which time the emu is far away. The emu can exhaust its predator before the predator can catch up with it.

Emus are great natural insecticides. They eat insects and caterpillars, and one adult emu, when killed, was found to have more than 3000 harmful caterpillars in its stomach.

By the way, I told you about how emus escape their predators by putting one wing up and the other down and swiveling around, but there's something else really interesting about them. They're playful and they like people. We know a lot about how they communicate with each other and one of their signals for, "I want to play tag," is to thrust their breasts in a kind of scooping motion towards the ground. When I was visiting with a local emu grower, she had me do this when in one of their football-field size pens and then run away from the emus. They chased after me, and then when I turned around, they ran away from me. We continued this game of tag for about five minutes until I was exhausted. I thought at the end of all this chasing that they'd be afraid of me, but instead, they came up to me and one lay her head on my arm so that I'd scratch her neck for her.

The Rhea

The rheas are a South American cousin of the ostrich and they're about the same size as an emu, that is, about 6 feet tall and weighing around 150 pounds.

They defend themselves in a different way from the emu, though. A rhea has a spur at its heel that looks like a smaller version of the horn on a cow. The rhea can kick with a force of 800 pounds per square inch, and an adult rhea has little to fear from any predator except man. I have friends who raise them, and they tell me that rheas are more difficult to raise then emus. Rheas can be fiercer, less playful, and can cause you real harm if you annoy them enough. The rhea's egg is a lovely creamy white. Like the emu egg, it's easier to carve than an ostrich egg and it holds up better than a goose egg.


The Cassowary


The cassowary is a large, flightless bird native to Australia and New Guinea where it lives in tropical rainforests. It is a member of the Ratite family which makes it a cousin to ostriches, emus and rheas. Like its better-known family members, the cassowary is a powerful bird equipped with impressive defense capabilities. It has a strong kick and sharp talons that aid in its defense.

Although the cassowary is very colorful, it can be difficult to sight in the wild. This is especially true now that it has been added to the Endangered Species list. It is for this reason that only the eggs from cultivated birds are used for decoration.

An interesting thing about the cassowary is that the male is responsible for incubating the eggs and tending the young. Females may lay eggs in the nest of more than one male but her role is complete once the eggs are laid.

The horn or helmet you see on the male bird pictured left is made up of cartilage. It is thought to attract females.