A pair of whooping cranes that produced a chick in 2006 that now migrates between Florida and Wisconsin has done it again.

Experts say the chick hatched June 14 or 15 at Necedah National Wildlife Refuge in Wisconsin. The existence of the chick wasn't confirmed until last week because of dense vegetation.

Researchers trying to save the endangered cranes have worked for nine years to create the migratory flock. The group Operation Migration has trained the cranes to make the Wisconsin-to-Florida trip by leading them in an ultralight airplane.

The chick born in 2006 was one of two that the parent cranes hatched that year. The other was killed by a predator.