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Rare & Sensitive Species

Rare & Sensitive Species

From the lush prairie and grassland to the heights of the craggy summits of Boulder's mountain backdrop, Open Space and Mountain Parks provides a protected refuge for animals and plants that are rapidly vanishing elsewhere. 

Many of these rare species are protected in special Habitat Conservation Areas on OSMP.

Meet Some of our Rarest Residents

The rare White Adder's Mouth Orchid, which grows wild on Green Mountain, is known from no other site in the entire state of Colorado!

Hiding in tall wetland grasses lives a small, shy mouse with a long tail: the Preble's Meadow Jumping Mouse. This nocturnal mouse is now listed as threatened with extinction by the U.S. Fish and Wildlife. Photo by Tamara Gorel.

Although they may seem to be everywhere around Boulder, Black-tailed prairie dogs have been decimated in the West.  Approximately 98 percent of the their habitat has been destroyed since Euro-American settlement.

The Hops Blue butterfly is known from a few sites along the Front Range, and no where else in the world. It and its food plant, wild hops, are strictly protected on OSMP. Photo by Dr. Paul Opler.

The Ute Ladies' Tresses Orchid is known from only a handful of sites in the western United States. Cattle grazing and prescribed burning help protect its habitat in wet OSMP meadows.

Townsend's Big-eared Bats spend the months of April through October on Open Space and Mountain Parks land. Multiple females bearing one pup each seek roosting sites in caves along the Front Range. Two of Colorado’s 11 known maternity colonies are found on OSMP. To protect  the breeding bats from disturbance and the possible spread of the deadly white-nose fungus, OSMP has gated both caves that house the colonies.

Pups are raised in a nursery system under the watchful care of many mothers. But even under normal conditions without human interference, pups suffer high mortality rates. Those that survive through fall migrate short distances to higher elevations. Once arriving in a colder climate, the bats hibernate until their April return. These bats are protected by wildlife closures.

Wood Lilies are one of the plant species on Open Space and Mountain Parks which are listed as rare and imperiled by the Colorado Natural Heritage Program. Collecting has been a factor in this plant's decline.

Paper Birches on Green Mountain were cut off from the rest of their kind when the climate changed at the end of the Ice Age! The nearest paper birches are now found in Nebraska. The tall prairie grasses of the foothills are also relics - leftovers from the Ice Age climate. Colorado's only paper birches are protected in the Western Mountain Parks Habitat Conservation Area.

The Golden Eagle is one of two large brown eagles residing in North America. Females are generally larger than the males; juveniles tend to be much darker than the adults. Golden eagles in the Boulder area are not true migrants. Because their diet consists of small to medium-size mammals (such as prairie dogs - see photo above) that exist year round, the eagles simply expand their home territory during winter. Golden eagles tend to use the same nest site for many generations. They can be seen carrying nesting material to enlarge or repair an older nest. These materials consist of various kinds of sticks, especially pine boughs. These scented boughs act as parasite control by repelling insects that find the smell unappealing. These birds are protected by wildlife closures.

Peregrine Falcons are found throughout North America but are not common anywhere. Plumage varies distinctly between adults and juveniles. Adults have dark heads with dark mustache marks that contrast sharply with black streaking on white underparts. Juveniles have darker underparts such that the black streaking is not quite as prominent. Unlike the Golden Eagle, most Peregrines search for ledges on a rock face rather than a nest. They scrape out any debris that has fallen on the ledge during the winter or previous years.

In 1991, the first pair since 1958 returned to Open Space and Mountain Parks. Due to increasing numbers in the United States, the Peregrine Falcon was downgraded from "Endangered" to "Threatened" on the federal endangered species list in 1999. These birds are protected by wildlife closures.

The Prairie Falcon looks much like the Peregrine, although its coloration is overall more pale. Rather than a stark black and white contrast, Prairie Falcons have gray spots on a much whiter underside. Prairies are also far more common on Open Space and Mountain Parks than the Peregrines. Both species of falcons scrape debris out from the desired nest site. The ledge is known as an eyrie; sometimes potholes or other indentations in the rock face are used. These birds are protected by wildlife closures.

The vanishing Prairie Gentian wildflowers are protected on OSMP's pastures. They occur in wet meadows east of Boulder, such as the Lower Boulder Creek Habitat Conservation Area.

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