This past summer, my wife Cassandra and I took a road trip down to Arizona.

We camped and went birding in several of the small mountain ranges in the regions surrounding the city of Tucson in the southeastern part of the state.

These mountains are rich in biodiversity, including birds.

Southeastern Arizona is actually a major bird-watching hot spot in the U.S.

It's a magical place, home to special birds like the elegant trogon, Arizona woodpecker,

Mexican jay, red-faced warbler, and blue-throated mountain gem, which is a hummingbird.

My first experience exploring this region was in 1999, when I worked as a volunteer research

assistant in the Chiricahua Mountains.

Of the dozens of small, isolated ranges in the region, the Chirikawa's are the largest and most

biologically diverse. I spent the summer of 1999 hiking around in the high country of those mountains

at elevations around 9,000 feet, or 2,700 meters.

The forest up there was a lush mixture of pines, furs, and aspen trees.

Beneath the trees, the undergrowth was thick with shrubs, wildflowers, and

mushrooms. Fast forward 22 years to my recent trip with my wife. After over two decades, I had

finally returned to the higher reaches of the Chiricawa Mountains. And you know what? I hardly

recognized the place. The forest was much thinner than I remember, and the trees smaller.

Unlike the dense, shady forest of my memory, bright sunlight was shining between the trunks now,

and many slopes were relatively bare of trees altogether.

"'Was I shocked to see this dramatic transformation?'

"'No, not at all. I already knew what had happened.

In the summer of 2011, a massive fire erupted in the Chirikawa Mountains. It raged for about

six weeks and scorched over 224,000 acres, which is about 91,000 hectares. Almost the entire mountain range

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