The 75-million-year-old rocks of Alberta's badlands yielded fossils of Ornithomimids, ostrich-like dinosaurs that had feathers and wing-like structures, the Calgary Sun reported.
Ornithomimids were too big to fly, researchers said, so the wing-like features developed in adult specimens may have been used for mating display or to care for eggs.
"The fact that wing-like forelimbs developed in more mature individuals suggests they were used only later in life, perhaps associated with reproductive behaviors like display or egg brooding," Francois Therrien of the Royal Tyrrell Museum said.
The researchers found proof of feathers preserved in three fossil skeletons, a juvenile and two adults.
"This is a really exciting discovery as it represents the first feathered dinosaur specimens found in the Western Hemisphere," Darla Zelenitsky of the University of Calgary said.
Until now, feathered dinosaurs have been found mostly in China and in Germany.