A Global Hotspot for Biodiversity

The Siskiyou Crest sits at the center of the world class Klamath-Siskiyou region. The mountain ranges and river valleys that define this region are some of the most spectacular in America and support globally important concentrations of biological diversity.

“The Klamath-Siskiyou ecoregion of southwest Oregon and northwest California has long been recognized for its global biological significance and is considered an Area of Global Botanical Significance by the World Conservation Union, a global Centre of Plant Diversity, and has been proposed as a possible World Heritage Site. More recently, World Wildlife Fund US scored the Klamath-Siskiyou as one of their Global 200 sites reaffirming its global importance from the standpoint of biodiversity.”
-- Stritholt J.R., R. F. Noss, P. A Frost, K. Van-Borland, C. Caroll, G. Heilman, Jr. 1999. A conservation assessment and science based plan for the Klamath-Siskiyou

“Based on comparisons of species richness, endemism, unique evolutionary and ecological phenomenona (e.g., species migrations, adaptive radiations), and global rarity of habitat types, scientists have ranked the biodiversity of the Klamath-Siskiyou Ecoregion among the world’s most outstanding temperate coniferous forests.”
• DellaSala, DA, Reid, SB, Frest, TJ, Strittholt, JR, Olson, DM Natural Areas Journal [Nat. Areas J.]. Vol. 19, no. 4, pp. 300-319. Oct 1999. A Global Perspective on the Biodiversity of the Klamath-Siskiyou Ecoregion

The Siskiyou Crest offers one of the best conservation opportunities in the United States to preserve and restore such a wide-ranging assemblage of ecosystem types and roadless forests with such a rich abundance of species in a relatively small reserve area. Referring to the ‘Siskiyou Biome’, the Bureau of Land Management (BLM) writes:

“This biome has a diversity of wildlife and habitats not usually found in such a limited area. ODFW (2005) identifies the Siskiyou mixed conifer forests and woodlands as the most diverse forest habitats in Oregon. The Klamath Mountains are considered to be a herptile "hotspot" by Bury and Pearl (1999), supporting 38 native species of amphibians and reptiles. . .higher than any similar-sized mountain range in the Pacific Northwest (Olson et al. 2001). Sixty-five Bureau Sensitive and Federally Listed are documented or suspected in the Siskiyou Biome.

The highest avian species richness west of the Cascade crest in Oregon and Washington occurs in the Klamath Mountains (Ralph et al. 1991). The Klamath-Siskiyou ecoregion is an area of "extraordinary biodiversity," rated "among the world's most outstanding temperate coniferous forests" (Dellasala et al. 1999). They analyzed 2,377 terrestrial animals (including snails, butterflies, birds, mammals, reptiles and amphibians), and 168 or 7 percent were found nowhere else.

Influenced by both the Mediterranean climate of California and the strong marine influence of the Pacific Northwest, as well as a combination of soil types including a large area of serpentine, the Siskiyou Biome is one of the most botanically diverse in North America (Stein et al. 2000). Approximately 2/3 of the known rare plants and fungi (97 species) in Western Oregon occur in the Siskiyou Biome. This botanical diversity was a major reason for the creation of the Cascade Siskiyou National Monument in 2000. Unique plant communities in the Siskiyou biome are threatened by starthistles, knapweeds, thistles, brooms, puncture vine, knotweeds, Dyers woad, leafy spurge, loosestrife, false broom, yellow flag iris, and Sudden Oak Death.”
--From BLM Vegetation Treatments Using Herbicides on BLM Lands in Oregon DEIS Chapter 4, page 211, Affected Environment and Environmental Consequences and Vegetation, Native Plants, and Plant Communities, page 112.

“In 1975, Wayne Roderick of the University of California Botanic Garden, Berkeley, asserted in the Journal Four Seasons that Cook and Green Pass (at the center of the proposed monument) has ‘the largest single aggregation of native plant species known to occur in one limited area in California.’” --Page F-7, Rogue River National Forest FEIS, Land and Resource Management Plan

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