Clark's Nutcrackers.

Two light-grey and black Clark’s nutcrackers (robin-sized birds) perch on caramel-coloured seed cones atop a limber pine tree, in Banff National Park. The bird on the left is hanging upside-down with its beak buried in a cone, seeking seeds. The bird on the right is standing with its feet straddling two cones, with a seed clutched in its beak. The background is a blurred dark-grey.
Limber pine and whitebark pine trees each have a similar symbiotic relationship with the Clark’s nutcracker. These birds rely on the seeds of both trees for survival, and “cache” these seeds in the ground for a reliable food source through winter. Some of these buried seeds are forgotten or missed by the birds, and may later germinate and grow into new seedlings. Though found at lower elevations, limber pines share a similar overall ecology with whitebark pines, and are threatened by the same factors. This tree is currently under review to be listed as an endangered species in Canada under the Species at Risk act, alongside its close relative the whitebark pine (which is already listed), and biologists are taking similar steps to conserve both species in Canada’s mountain parks.