An army is building watchtowers in the prairie



A prairie dog sentinel awaits!



Yip! Yip The call resonates. They spotted the intruder long before me And what an intruder!



This badger is a powerful, active, solitary hunter, very different to our Eurasian species. I've never seen an American badger before, but the prairie dogs have, and their alarm calls sing out across the plains.



But they are safe, today. The badger catches nothing, and eventually wanders away.

Prairie dog towns are the city centres of the grasslands, bustling, lively, prone to attract surprising guests. These creatures are entertaining and photogenic...





...but there is so much more to them than meets the eye

Once upon a time, there were at least 200,000,000 of these large ground squirrels in the Great Plains - a single colony in the 19th century was estimated to house ten million - but they have gone, like the wolf and bison, in most of their original range. They have been heavily persecuted by livestock interests, and they are still greatly hated in some quarters as perceived grazing competition for cattle, but they are also the cornerstone for so much native prairie life. Many predators are interested by them...



...but other creatures just benefit from the changes that they exact upon the environment. Pronghorn antelope, the fleet-footed spirits of the prairie, are frequently found in prairie dog towns, and graze the new growth that appears after the dogs clip the tall grasses.



(I think they win the award for the most beautiful ungulate in the Americas )



Bison, the largest mammals on the continent, also utilise the new growth, although this individual was out on a ridge.



Smaller mammals, such as white-tailed jackrabbits, also drop by.



The jackrabbits may be merely visitors, but reptiles such as horned lizards find warmth in prairie dog burrows. In the springtime, the justifiably famous burrowing owl is also to be seen Some smaller ground squirrels also use the towns, although studies suggest that the Richardson's ground squirrel is present less frequently than other species.



Grasslands and its surrounds are the last place in Canada with prairie dogs. The park has thus become a lifeline to their most specialised predators, one of the world's rarest mammals: a slender, bandit-masked mustelid that vanished completely from the wild in 1985 after the last handful were captured in Montana for a desperate, last-ditch captive-breeding rescue attempt. Black-footed ferrets were reintroduced into Grasslands just two weeks ago and hopefully they will thrive here. I didn't glimpse one; they are nocturnal, shy and still doubtless learning about their new habitat.

The prairie dogs should sustain them, just as they aid so much other life. Just like the wolf, they are a keystone species - one disproportionately important to the survival of the rest of the ecological web. The prairies would be a much poorer place without them