Filtering by
- All Subjects: Grand Canyon National Park (Ariz.)
- All Subjects: Conservation
- All Subjects: Birds
- Creators: United States Department of the Interior
- Creators: Cantrell, Christopher
- Creators: Kolb Bros.
- Creators: Mitchell, Guy E.
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Black and white print of five women and one man riding mules on the Bright Angel Trail. A wooden sign next to the trail says, "Photo by Kolb Bros." Handwritten annotation, "Annie Goodenough on Bright Angel Trail."
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Handwritten cover titled, "Nature Notes of Grand Canyon, Polyphemus Moth, Female, Found at Grand Canyon, 5 July 1928, Vol. 3 - No. 2." Cover includes a drawing of the moth.
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Typescript report, black and white, describing the birds of Grand Canyon National Park with cover drawing of a bald eagle.
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Typescript report, black and white, describing the mammals of Grand Canyon National Park with cover drawing of a bighorn sheep.
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Apache trout is a federally threatened salmonid native to headwaters of the Little Colorado, Black, and White rivers in east-central Arizona. Decline of Apache trout to threatened status was attributed to over-fishing, habitat degradation and negative interactions (predation, competition and hybridization) with introduced nonnative salmonids. Although over-fishing is no longer considered a threat, habitat degradation and negative interactions with nonnative salmonids continue to threaten Apache trout, and it is towards these threats that recovery actions are directed. While barrier construction began in 1979 and livestock exclusion began in the mid-1980s, the efficacy of these recovery actions at increasing Apache trout abundance and improving habitat condition had not been evaluated. We therefore initiated a study to evaluate the efficacy of riparian fencing and barriers.