The alpine tundra is the fragile community of grasses, sedges and dwarf plants that occurs above treeline in the Rockies. In Colorado, treeline is typically somewhere in the neighborhood of 11,500 feet. There is no other place besides the tundra to find White-tailed Ptarmigan. In summer, the most conspicuous breeding bird is usually American Pipit. Brown-capped Rosy-Finch is also found above treeline in summer, usually around exposed rock faces and permanent snowfields. It is more likely to be found in the steeper, rockier areas, while ptarmigan and pipits favor the grassier areas. Golden Eagles and Common Ravens hunt on the strong winds above this habitat, which is frequented by bighorn sheep, yellow-bellied marmot, and the cute little rabbit-like animal called the pika.
The tundra is one of Colorado’s most unique habitats. Although many other western states have areas of tundra, Colorado has more of it than anywhere else in the lower 48. Isolated from other patches of tundra since before the last Ice Age, Colorado’s tundra is home to many species whose closest relatives are found thousands of miles away, in Siberia. For example, the very rare Uncompahgre Fritillary butterfly is found only in Colorado, on the tundra of a handful of peaks in the high San Juans. Its closest relatives are found in tiny patches in the mountains of Wyoming, Canada, and central Asia. More common butterflies of the tundra are Phoebus Parnassian, Mead’s Sulphur, Colorado Alpine, Melissa Arctic, and Lustrous Copper.
The wildflowers of the tundra are legendary for putting on a dramatic show in the summer. To cope with the extreme weather conditions, many of them have evolved to become far tinier than their downslope relatives. You will want to get down on your hands and knees to fully appreciate the beauty of moss campion, alpine avens, alpine primrose, alpine forget-me-not, and big-rooted springbeauty.
Because the tundra is so fragile, it is very important to treat it with care. Whenever possible, walk on rocks or snow rather than on the plants. If you must walk on the plants, try not to blaze any new trails through them; when hiking off-trail in a group, hike abreast of one another instead of single-file.
