Whooping crane eggs: one or two?
A University of Alberta scientist says removing an egg from an endangered whooping crane's nest increases the species chances of survival.
Mark Boyce, from the Faculty of Science, studied the policy of removing one of two whooping crane eggs from a nest at Canada's Wood Buffalo National Park and raising it in a "foster-parenting" program.
Cranes usually rear a single chick and the other dies or is killed by predators. The egg removal program was started by Ernie Kuyt, an Edmonton-based scientist who reasoned that one egg could be taken and used for artificial propagation programs.
But the Canadian government prefers no future egg collections occur in the national park due to concerns that egg removals may reduce the productivity of the whooping crane population.
Boyce says his research found taking one egg away actually increases the probability of nest success.
His paper -- co-authored by Subhash Lele of the university's mathematical and statistical sciences department and Brian Johns of the Canadian Wildlife Service-- appears in the December issue of Biological Conservation.
Copyright 2005 by United Press International