Even if mating isn't a concern, knowing the sex of your cockatiel is useful. You can give your bird a gender-specific name and use an accurate pronoun when talking about the bird. It'll help you personalize your relationship. To crack this egg, monitor your baby cockatiel's behavior and coloring.
Listen to what your bird has to say. Female cockatiels don't sing, but the men typically love to show off their pipes. If your cockatiel is singing, he's certainly a male. If the cockatiel's repertoire isn't much more advanced that chirps and squawks, your bird's likely a female.
Look long and hard at your bird's face. Cockatiels are often recognizable for their cheek patches, which give them their rosy-cheeked appearance. On a male, the cheek patch contrasts against a face mask, which is a different color from the rest of the body. On a female, the face mask is either the same color as the rest of the body or very close to it.
Watch how your bird behaves. As males grow older and their hormones start to rage, they can become more aggressively showy, doing things like hopping around, nipping and wildly tapping with their beaks. Females, on the other hand, tend to become more sedate, opting to brood quietly, rip up the paper in their cages and look for cozy places suitable for nesting.
Check under the wings. Grown females tend to retain spots or stripes on the undersides of their wings, while males have solid coloring.
Tom Ryan is a freelance writer, editor and English tutor. He graduated from the University of Pittsburgh with a degree in English writing, and has also worked as an arts and entertainment reporter with "The Pitt News" and a public relations and advertising copywriter with the Carnegie Library of Pittsburgh.