Sky Islands of North America: A Globally Unique and Threatened Inland Archipelago

"Sky islands" are a globally unique convergence — the north-south overlap of two major cordilleras spanning the temperate and subtropical latitudes, covering some 40 distinct mountain ranges in the southwestern U.S. But they are at risk.

2 minute read

January 15, 2008, 6:00 AM PST

By sbuntin


"With the theater set and the actors revealed, the ecological play within the Sky Island region is complex, diverse, and fragile. How does all this ecological complexity interact with the human element upon the landscape?

Unfortunately, today the stage is being dismantled piece by piece. The greatest threat to the region's natural heritage is not unlike that which plagues our planet's other biodiversity hotspots-habitat loss and fragmentation-though it's progression of degradation is occurring at breakneck speed here.

Historically, species decline, extinction, or extirpation (local population extinctions) often came at the hands of government trappers and hunters, aided by a general societal conviction that wolves, bears, wild cats, prairie dogs, and many other species should be done away with at every opportunity. At one time, the idea was that these "vermin" stood in the way of agricultural development, and should be removed to make the area safe for colonization. From roughly the early 1800s through the middle 20th century, it wasn't so much that habitat didn't exist to support populations of native wildlife as it was that full-scale persecution brought their numbers to all-time lows.

The U.S. and Mexico crusades against the Apache Indian culminated in 1886 with the capture of Geronimo and his remaining band, then cattle grazing and mining safely moved in and took their toll on the region's grasslands and woodlands. The ecological effects of the late 1880s and early 1900s are still felt today, though most scientists agree that, comparatively, today's landscape is healthier than it was then. Except now, new and direr threats appear."

Thursday, January 10, 2008 in Terrain.org: A Journal of the Built & Natural Environments

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I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching. Mary G., Urban Planner

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching.

Mary G., Urban Planner

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