First years and adult males are distinguishable through close observations of the skull and its degree of ossification. Juvenile skulls have a slightly pinkish color that gives under pressure due to its singular layer. Adults instead have a double layer skull, which gives more resistance when applying pressure. First year birds also tend to have a fleshy, yellow gape in the corner of the mouth, apparent in all months except October and November. When comparing males to females that both have brown molt, increased wing length and weight typically indicate a bunting is a male.