Have you herd? Moose, bighorn sheep pass on migration tips
NEW YORK — Looking for the best place to eat? Ask a local. Now scientists say that same insider knowledge shapes the springtime migrations of moose and bighorn sheep.
Animals learn from experienced members of the herd about where to find the best food, building sort of a cultural know-how that’s passed through generations and improves over the course of decades, new research indicates.
While scientists have speculated before that this happens in hoofed animals, this is the first conclusive test of the idea, said Matthew Kauffman, a U.S. Geological Survey researcher who was part of the study released last week by the journal Science.
Researchers tracked the movements of 267 bighorn sheep and 189 moose in Wyoming, Idaho and South Dakota that wore GPS devices on collars. They used satellite data to track where and when vegetation along the migration routes reached the stage of growth that the animals prefer for eating.
Some of the collared animals came from herds established in an area for at least 200 years, while others came from herds introduced in recent decades.
Scientists reasoned that if animals learned and then developed over time the knowledge of how to find the best food, those from long-established herds would perform better at locating the prime forage than those from herds with a shorter history.
And that’s what they found when they compared the GPS data on the animals to the locations of the best forage. The longer a herd had been established, the better the tracked animals were at finding the best forage, and the more likely they were to migrate at all.
The long, slow improvement in forage-finding over decades indicates herds build on the cultural knowledge across generations. The longer a herd had been around, the better the tracked animals were at finding the best forage, researchers found.