There are very few things I enjoy more than exploring back roads on a summer Sunday. Luckily, for a short time at least, wandering the watershed was a small part of my job description and I explored southeastern Alberta taking photographs and writing about its landscape and biodiversity for the South East Alberta Watershed Alliance.
Very few people visit Red Rock Coulee Natural Area – or have even heard of it – but it boasts some incredibly distinct geology and wildlife, especially for an area that most Albertans think of as parched, dull, and lifeless. While there is no doubt that Red Rock has a desert-like landscape, the coulees, the cactus, and the clay-coloured hills have a certain charm, and huge red rocks scattered throughout the area are a pretty good reason to venture into a somewhat neglected corner of the province.
The government of Alberta uses a variety of mechanisms to conserve or protect public (Crown) lands, and there are different levels of protection that specify types of allowable uses. Red Rock Coulee covers 324 hectares of Crown Land. It has been designated as a Natural Area, which means that permitted uses include low-intensity nature-based recreation, and nature and heritage appreciation and education. Natural Areas are meant to preserve and protect special or sensitive landscapes, or features of regional and local significance. Most Natural Areas include natural and near-natural landscapes and have no facilities other than parking areas or trails. Red Rock Coulee is typical in that way, not flashy or impressive; no bathrooms, no paved paths. There is, however, a small, well-used picnic table near the parking area, and at almost 1000 feet in elevation, the long view alone can make the trip worthwhile.
Red Rock Coulee gets its name from the large round sandstone boulders littering the area. The boulders are a type of “concretion;” and, at up to 2.5m across, are considered among the largest in the world. The word concretion comes from the Latin “con” (together), and “cresco” (to grow). Concretions are found throughout the world though they vary considerably in their size, shape, hardness and colour, and even method of growth. It is believed that the Red Rock concretions formed in prehistoric seas as layers of sand, calcite and iron oxide collected around a nucleus formed by shells or bones. Layers of mineral continued to be deposited over time, and if you look closely at some of the concretions, you can see their “growth rings.” Concretions can be found embedded within a variety of rocks but are particularly common in shales, siltstones, and sandstones. The boulders are more resistant to erosion than the bedrock they are found in, and at Red Rock Coulee, the comparatively weak bedrock of the 75 million-year-old Bearpaw Formation has eroded from around them leaving the concretions behind. At several places in the Natural Area, you can see concretions just starting to emerge as the surrounding ground is slowly washed away.
Soils are thin in this region and bedrock is close to the surface and, as a result, the Natural Area boasts less typical prairie landscapes within the rolling terrain. Water erosion has carved ravines (coulees) and badland landforms such as hoodoos. Exposed bedrock can be seen throughout the area, the different coloured bands on cliffs representing different shales, sandstones, clays and an iron-cemented sandstone known as ironstone.
Southeast Alberta has a semi-arid climate, and mid-day heat typically keeps wildlife out of sight. If you visit early or late in the day, however, there is a good chance you will see mule deer, pronghorn antelope, or jackrabbits. There is also a fairly good chance you will spot a coyote or one or two Richardson’s ground squirrels (gophers). Western rattlesnakes and bull snakes are less common, and short-horned lizards and scorpions are rare but they have been spotted here. If you are a bird watcher, you might see or hear rock wrens, western meadowlarks, lark buntings, horned larks, nighthawks, and grasshopper sparrows. Plant lovers can expect to see several species of short and dry-mixed grasses and common prairie wildflowers, as well as sagebrush, wild rose, juniper, prickly pear and pincushion cactus, prairie crocus, and gumbo primrose. If you look closely at the concretions, you will see patches of orange, black and grey lichen that has previously been identified as Xanthoria.
Medicine Hat is 265 km from Calgary, and Red Rock Coulee Natural Area is located on Highway 887, near the hamlet of Seven Persons, about 40 minutes south-west of Medicine Hat. On a clear day, you can see the Sweet Grass Hills of Montana, 100 km to the south. On the day I visited Red Rock Coulee we ventured south for a better view of the Hills and met a moose wandering across the road… one never knows what one might find…
By Maggie Romuld