I would suggest that when people posted to eBird they might not have had the advantage of the band information.  They posted what they saw, and at some point an immature looks like an adult if you don't know it's birthday. 

Jean Leonatti
Sent from my U.S. Cellular® Smartphone

-------- Original message --------
From: Al and Lois Smith <[log in to unmask]>
Date: 05/22/2016 1:21 AM (GMT-06:00)
To: [log in to unmask]
Subject: Whooping Cranes

How can the four Kaskaskia whoopers be Immature 2/20/16 and not 5/20/16, it's only three months apart? People are listing them as immature and adults on eBird.  All are from the same year class. #s 61_15 (F), 62_15 (M), 63_15 (M), and 67_15 (F).
Text below from this site.
"A group of five of these 2015 DARs left Horicon NWR completely on their own, December 19th – not with sandhill or whooping cranes. They are #s 61, 62, 63, 65, and 67, and they were reported in an update from the Whooping Crane Eastern Partnership (WCEP) as located for a while in McHenry County, IL; #65-15 soon split from the group and followed a group of sandhills to the Goose Pond area of southern Indiana. The other four continued southwest, and are located on the border of Randolph County, IL and Sainte Genevieve County, MO."
The photos from these two days show leg bands confirming these are the same birds.

Al Smith

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