Important Bird Areas

Marble Canyon and Vermilion Cliffs

This IBA is the Colorado River corridor and adjacent side canyons from Glen Canyon Dam to the mouth of the Little Colorado River. Total length is 125 km.

Tracking of California Condors by biologists shows considerable movement throughout the region. In spring and early summer 2004, as in earlier years, the birds frequented the Colorado River corridor along Marble Canyon and thence to the South Rim of the Grand Canyon, delighting Park visitors with splendid appearances and flights near enough for pictures.

Ornithological Summary

This IBA supports outstanding numbers of over-wintering waterfowl, up to 6000 birds total. The IBA is 20 miles from the release area for the re-introduced population of California Condors in Arizona, and provides a primary foraging and roosting habitat, along with the Grand Canyon National Park further downstream. The Peregrine Fund is the lead organization for the restoration of California Condors at Grand Canyon. Current information is available at http://www.peregrinefund.org. By the close of 2005, there were 59 free-ranging condors in the Arizona/Utah population. Reproduction among wild condors in Arizona reached new highs in 2004 and 2005, with two pairs producing young in each year. Condors 119 and 122 have fledged a chick in 2004 and 2005 from Battleship Cliff in the Grand Canyon below the South Rim and downstream from the IBA boundary. Wild fledged Condors are using the IBA as a travel and foraging corridorbetween the Vemillion Cliffs release site and the South Rim of the Grand Canyon. Wild Population of California Condors -- 127; Arizona 59.
A Great Blue Heron colony (3-4 pairs) exists within the IBA. The riparian habitat provides the best migration corridor in northern Arizona, and supports substantial numbers of passerines, gulls, raptors (especially Osprey), and Belted Kingfisher.

Conservation Issues

There is a serious threat from exotic invasive plants, particularly tamarisk and Ravenna grass. Other possible threats to birds include disturbance by waterfowl hunters and anglers above Lee's Ferry and heavy recreational boating occseasonal urring throughout the reach.

Ownership

Glen Canyon National Recreation Area and Grand Canyon National Park and the Navajo Nation.

Habitat

Habitats have not been fully documented in terms of vegetation species present, but include riparian, desert scrub, cliffs, and springs.

Land Use

Types of human uses occurring within this section of river include recreation (boating), fishing, and hunting.

Research and Conservation Projects:
From 1996 to 2000 a research study was completed on the aquatic and riparian bird communities of the Colorado River from Glen Canyon Dam to upper Lake Mead. No information on on-going conservation projects.

Protected Areas:
Management jointly administered between NPS, Glen Canyon NRA, Grand Canyon NP, and the Navajo Nation. No administered or designated protected areas.