The Center for Whale Research
Orca Facts
Orca Facts index:
• How do you identify
Killer whales?
• How do Killer whales
locate food?
• What do Killer whales
like to eat?
• How far do Southern Resident Orca pods travel?
• Why are Killer whales
black and white?
• Can you tell male calves
from females?
• Where in the world are Killer whales found?

Can you tell male calves from females?

Whale researchers at the Center for Whale Research, based on San Juan Island, have been documenting the local orca populations since 1976. During the course of this study over 95 whales have been born.

genitalsFor researchers, determining the gender of a calf adds a tremendous amount of information to the general understanding of the social structure and health of this local orca population.

To determine the gender of a new calf — or any orca whale — researchers rely on photographs of the underside of a whale when distinguishing a male from a female.

The difference is quite pronounced, if you know what to look for. Male orca whales have an elongated white pattern (above, left) stretching towards the tail in the genital region, while the females’ white patterns are much more rounded (above, right) with mammary slits visible.


Illustration courtesy Kelley Balcomb-Bartok/All Rights Reserved






























Question: Is the banner photo
at the top of this page of a male
or female killer whale calf?
(answer at bottom of next page)

© The Center for Whale Research. All Rights Reserved.
Site designed by Kelley Balcomb-Bartok.