Important Bird Areas

Bitterroot River

Montana

Within sight of the majestic Bitterroot Mountains to the west and Sapphire Range to the east, the IBA encompasses the 500-year floodplain around a 50-km stretch of the Bitterroot River from Woodside downriver to just south of Lolo and includes the Lee Metcalf National Wildlife Refuge. The riparian habitat is dominated by black cottonwoods and willows.

The boundaries of the IBA were made to correspond closely to the 500-year floodplain. The northern and southern boundaries of the IBA was based on capturing the most extensive cottonwood gallery forest present.

{link:For IBA map, click here.|http://mtaudubon.org/birds/documents/bitterrootriver_web.pdf}

Ornithological Summary

More than 240 species of birds have been recorded within the IBA, with at least 115 species breeding. Numbers of Lewis's Woodpeckers and Red-naped Sapsuckers in the cottonwood forest along the river exceed the respective thresholds for an IBA of Continental significance. Other species of conservation concern that nest here include Bald Eagle, Northern Harrier, Wilson's Phalarope, Short-eared Owl, Pileated Woodpecker, Willow Flycatcher, and Red-eyed Vireo.

Conservation Issues

The human population in the Bitterroot Valley has grown substantially during the last 20 years, and housing developments are quickly eating up open space and wildlife habitat and reducing the number of people who maintain a rural existence. Although cottonwood stands are healthy in some areas, invasive weeds, overgrazing, and erosion have degraded some of the riparian habitat.

Ownership

Most of the land within the IBA owned by individuals, with some 1,118 private landowners. Only 11 of these owners have more than 1,000 acres; 4,332 acres (14.4% of IBA) have been placed in conservation easements. The IBA also includes the Lee Metcalf National Wildlife Refuge.

Habitat

The riparian forest consists mostly of black cottonwood and various species of willows. Grasslands are a mix of native bunchgrasses and exotic perennials and annuals.