Distinguishing between adult male and female budgies is straightforward: Males have a blue cere -- the area above the beak that contains the nostrils -- while females have a tan or brown cere. It's a bit more difficult to determine the sex of babies because the cere changes color as they age, but there are some telltale signs.
White Cere: She's a Girl
The most reliable way to tell a baby budgie's gender is to look at the area around the nostrils. A baby with whitish nostril areas is female. Don't expect to see bright, definitive rings; they can be faint, but if you look closely you'll see white.
Don't Let Baby Blue Fool You
Many baby budgies have a blue cere, including females. A female's cere is usually a lighter shade of blue than a male's cere, however, along with having the whitish color around her nostrils.
Sans White Cere, He's a Boy
A male baby's cere can start out blue, pinkish or tan. Ignore the color of the overall cere and just look for white around the nostrils to indicate a female. If there's no white, he's a male.
Ceres at Maturity
As the months go by, a baby's cere can continue to change colors. A male's cere may change from pinkish to dark purple, and then blue, which it will remain. A female will gain more white around her nostrils with tan starting to appear, before her cere turns totally tan or brown. At 12 months, budgies have the cere color they will carry into adulthood.
Barbara Bean-Mellinger is an award-winning writer in the Washington, DC area. She writes nationally for newspapers, magazines and websites on topics including careers, education, women, marketing, advertising and more. She holds a Bachelor of Science from the University of Pittsburgh.