Eggs from Many Places: Building Genetic Diversity
Thank you, Sara Zimorski
Eggs are carefully shipped in special boxes.
Photo Bev Paulan, Operation Migration for WCEP

Where Do Eggs for the New Flocks Come From?
Each spring, some special Whooping Crane eggs laid by captive cranes are packed for traveling. They're shipped to Maryland's Patuxent Wildlife Research Center from captive breeding facilities across the US and Canada. Why? At first there were no adult cranes in the new eastern flock. That meant no eggs and no baby chicks. The solution was to take eggs laid by captive Whoopers. Those eggs could hatch into chicks to become part of the new Eastern Flock, and later also for the new Louisiana nonmigratory flock. The captive whoopers live at breeding facilities that are part of the Whooping Crane Eastern Partnership. Captive whoopers are helping to bring g Whooping Cranes back to Eastern North America where they were wiped out decades ago.

Building Genetic Diversity
Getting eggs from different places is important. Doing so makes the gene pool of the Eastern Flock more diverse; more diverse genetics create stronger, more resilient birds. For example, the first eight birds for the Class of 2007 came from The San Antonio Zoo (#702), The Calgary Zoo (#703 and #706), The Patuxent Wildlife Research Center (#704, #707 and #710) and a poorly placed nest in the Florida Non-migratory Population (#708 and #709). Additional chicks came from The International Crane Foundation (ICF), The Audubon Centre for Research of Endangered Species, and an abandoned nest in Wisconsin. That's a good variety of egg sources.

The parents of the Direct Autumn Release (DAR) birds also add new genetics to the Eastern flock. The DAR program allows pairs (particularly at ICF) who lay eggs too late to be included in the ultralight group to contribute their genetics to this new population through chicks that are released directly into the wild. These direct autumn release (DAR) chicks learn the eastern migration route by following older birds who were once part of the ultralight program.

Eggs from many places is an example of the power of partnership — the Whooping Crane Eastern Partnership — in action.

The Captive Flocks:
The crane-rearing buildings at Patuxent Wildlife Research Center are off-limits to the public. Eggs for the new ultralight-led chicks are hatched here.

The captive flocks consist of 148 (2010 figures) birds at five breeding centers and six display facilities. They play an important role in recovery of this endangered species:

  • These birds safeguard the genetic material of the wild birds.
  • They produce offspring for the ultralight-led and direct-autumn release (DAR) reintroduction programs.
  • Captive breeding facilities also provide homes for Whooping cranes with health problems that make them unsuitable for release into the wild.

Try This! Journal Questions
  • Why is a diverse gene pool important to the survival of a species?
  • How do you feel about keeping captive groups of an endangered species?


Journey North is pleased to feature this educational adventure made possible by the
Whooping Crane Eastern Partnership (WCEP).