Eastern Flock Nesting Failures: What Do Experts Think?

Joe Duff, Operation Migration
[The cranes] seem to be appropriately defending a territory and properly building their nest in good habitat. The eggs they lay appear to be healthy with the proper shell thickness and they share their nest duties. Most seem dedicated to the job of incubation at least until the Black flies hit.

It may be that the last Whooping cranes to nest in Wisconsin over 100 years ago didn’t have to contend with this problem. Climate change may have adjusted the Black fly season to coincide with their nesting or maybe it’s always been a problem. At any rate the next step is to analyze the data to see if Black flies really are the culprit. Thereafter we must determine if the problem is controllable and decide if we should continue to manage this population on into the future. Operation Migration Field Journal: May 28, 2009