Will they head east?
From the story:
The American mountain lion or cougar is now re-populating parts of the US, scientists say.
Their numbers had plummeted in the last 100 years because of hunting and a lack of prey.
Writing in the Journal of Wildlife Management, researchers say the cougar is now spreading far outside their traditional western habitats.
But they say the return of the big cats raises important questions about how humans can live with these predators.
Such has been the decline of the cougar in some parts of the United State that the US Fish and Wildlife service declared the eastern cougar extinct just last year.
For decades mountain lions were seen as a threat to livestock and humans and many States paid a bounty to hunters for killing them.
Their habitats were restricted to the areas around the Black Hills of Dakota. But in the 1960s and 70s the animals were reclassified as managed game species, so hunting was limited and numbers started to grow.
Read the rest at: http://www.bbc.co.uk/news/science-environment-18425472