Whooping Cranes at Wood Buffalo National Park in Canada fledged 37 youngsters from 36 sets of parents this year, according to the conservation group Friends of the Wild Whoopers. Parks Canada and the Canadian Wildlife Service released the information after aerial surveys were conducted in late July and early August.
This spring, the cranes had produced a near-record 97 nests. Now that the fledgling survey is in, we know that 61 nests failed to fledge a chick.
The cover story of the September/October 2019 issue of BirdWatching is about Whooping Cranes. It says: “In 2017, a record 63 chicks fledged at Wood Buffalo. In 2018, 87 nests were counted but led to only 24 fledglings — a low number but ‘still within the natural range of variation that we would expect from this species,’ according to Rhona Kindopp, manager of resource conservation with Parks Canada.”
Annual variations in temperature and rainfall in spring and early summer play a part in the success of breeding Whooping Cranes.
“It appears that conditions at the park were better than last year,” according to the Friends group. “May rainfall was only 84% of normal, however, in June rainfall was 141% above normal, with most (22mm) of that falling on June 2 just as some of the chicks were hatching.”
About 500 cranes make up the population that nests at Wood Buffalo and winters on and around Aransas National Wildlife Refuge, on the Gulf coast of Texas. The birds will begin the 2,500-mile southbound flight in mid-September and early October. The trip takes up to 50 days. After two days, the cranes arrive at a staging area in Saskatchewan, where they remain for one to five weeks, feeding in wetlands and grain fields. They then fly the rest of the way in about one week.
This year, the Whooping Crane’s eastern migratory population, which breeds in Wisconsin, produced 19 wild-hatched chicks. As of early August, only 3 to 5 are still alive. Currently, the overall eastern migratory population is estimated at 86 birds, not counting this year’s chicks. The total is one of the lowest in years.
A more recently established flock in Louisiana numbers 75 birds. This year, six chicks hatched, but none survived.