Something new to look at on juvenile night-herons?
Adult Yellow-crowned and Black-crowned Night-Herons look quite different, rarely presenting an identification challenge. Juvenile night-herons on the other hand can be challenging if you don’t know what to look for. There are a number of well-known differences. Yellow-crowned have longer legs and are lankier and more “heron-like” overall, while Black-crowned have shorter legs and are very stocky. Yellow-crowned are darker brown with sharply defined streaking, while Black-crowned are paler and more grayish with broader but more diffuse streaking on the chest. Yellow-crowned Night-Herons have an all-black bill, while Black-crowned have a large yellowish-green base to the bill. All these traits are easily picked by thumbing through your favorite field guide, but here is one you may not have heard before. Check out the greater coverts (the band of larger, plainer feathers underneath the feathers with the prominent spots at the tips) on the night-heron in the photo. See how they have crisp pale edges? Adult Yellow-crowned Night-Herons have pale edges to their greater coverts and it is a little known fact that juvenile Yellow-crowned Night-Herons also show this trait. Juvenile Black-crowned Night-Herons lack pale edges to the wing coverts and have larger pale spots at the tips of these feathers.
Certainly there are more obvious ways to separate juvenile night-herons, but given their tendency to roost in well concealed locations with only small portions of their bodies exposed it may serve you well at some point. If there is interested, I can go into more details on juvenile night-heron identification on a future Tuesday.
Cameron Cox currently leads photographic birding tours all over the world. To learn more about these tours or to sign-up for one, please visit the Tropical Birding website.