Sexing Cockatoos

SpeciesMethod
Bare-eyed Cockatoo aka Little CorellaThe female is usually smaller and the unfeathered area around the eye is shorter. But visual sexing is not definite. DNA or surgical sexing is recommended.
Blue-eyed CockatoosMales have brown eyes, while females have reddish brown eyes.
Ducorps CockatoosMales and females look alike. DNA or surgical sexing is recommended.
Gang Gang CockatoosSome of the lower abdomen feathers of the male is barred with orange, white and red. He has distinctive red markings on his head. The females’ lower abdomen is a duller orange and the white has a greenish caste. She lacks the red on the head that is so striking in the male..
Glossy Black CockatoosMales have black beaks and they are slightly smaller. They have brown feathers on the head. The females have horn colored beak; they don’t have any spots or bars on the body feathers. Immature birds look like females until they mature at about 4 years.
Goffins CockatoosMales and females look alike. DNA or surgical sexing is recommended.
Greater Sulphur- crested CockatoosThe males have darkbrown/black eyes. Females have reddish brown, deep burgundy eyes.
Leadbeaters Cockatoos (Major Mitchell’s)Males have dark brown eyes; while females have pinkish red eyes.
Lessor Sulphur-crested CockatoosMales have darkbrown/black eyes, while females have reddish brown to burgundy red eyes (when mature, about 3 years).
Moluccan (Salmon Crested) CockatoosMales have darkbrown/black. Females have deep brown to burgundy red eyes (when they mature). A small flashlight helps in determining eye color.
Palm CockatoosMales and females look alike. DNA or surgical sexing is recommended.
Red-tailed Black Cockatoos (Banks)Males have black beaks with a dull gloss on black upper parts. The chest feathers are greyish tipped and they sport a deep red tail. Females have horn-colored beaks, yellow spots on upper parts, and yellowish barring on chest. The tail has an orange red bar mixed with yellow. Immature red-tailed cockatoos look like females until mature at about 4 years.
Red-vented Cockatoos (Phillipine)Males have dark brown eyes, while females have reddish brown eyes.
Rose-breasted Cockatoos (Galah)Males have dark brown to black eyes. The eye of females are reddish brown
Slender-billed CockatoosMales and females look alike. DNA or surgical sexing is recommended.
Umbrella Cockatoos (White)Males have black eyes, while females have brown eyes. Immature umbrellas have greyish brown eyes.
White-tailed Black Cockatoos (Baudin’s)Males have black beaks, females have white horn colored beaks. Females are lighter in color and greater color variations exist. Females are slightly smaller and their yellow markings are more pronounced. Immature birds look like females until they mature at about 4 years.
Yellow-tailed Black Cockatoos (Funereal)Males have black beaks, females have white horn-colored beaks. The are lighter in color and greater color variations exist. Females are slightly smaller than males and their yellow markings are more pronounced. Immature birds look like females until they mature at about 4 years.

References:
Parrots and Related Birds by Henry Bates and Robert Busenbark
Online Book of Parrots – Cockatoos by Warner and Susanne Lantermann

Other Relevant Web Resources: