In the early '90s, environmental lawsuits seeking stricter protections for the goshawk threatened to restrict and even halt commercial logging in Arizona and New Mexico's national forests. The Forest Service -- with its mission to manage forests for multiple use and timber yields -- was in a tight spot, so it tapped Reynolds to gather data on the health of the Kaibab's goshawk population. Within a year, he was unrolling his sleeping bag at Big Springs, setting up the study on habitat structure and goshawk fitness that he's still working on today.
Soon after, he and a team of biologists and silviculturists developed the Goshawk Recommendations, a conservation plan for the birds, based on what they already knew about the species' food web. Pulling from hundreds of articles in scientific journals, they synthesized the habitat requirements of 14 of the goshawk's key prey species -- including the Steller's jay, cottontail rabbit and tassel-eared squirrel -- to produce a blueprint for an ideal forest. In 1996, the plan was officially adopted by the Forest Service's Southwest Region. From then on, national forests in Arizona and New Mexico were to be managed so that they would eventually mirror that master-image.
It was a very different picture than the one generated by prevailing management practices. During the 1980s, logging on the Kaibab and elsewhere in the Southwest cleared entire stands, leaving just a few mature trees to act as seed banks. Foresters then thinned the regenerating saplings to produce even-aged stands of uniformly spaced trees; it was a classic timber-centric model designed to increase the rate at which trees are grown and harvested. Outside of these heavily logged areas, the forests became clogged with small trees thanks to fire suppression.
The Goshawk Recommendations instead call for groups of trees with interlocking crowns separated by openings. The groups should be varied in age; that way, when a group of older trees dies, a batch of younger trees is already growing up elsewhere to replace it. The openings serve as flyways and foraging grounds for the goshawk, a sub-canopy hunter, provide natural firebreaks, and offer sunny spaces in which young trees can come up. "(It was) a paradigmatic shift," Reynolds says.
But some environmentalists don't see it that way. To create openings and maintain age diversity, the plan calls for the harvest of some large-diameter, old-growth trees. Reynolds' critics, many with a deep-seated distrust of the Forest Service's timber policies, cite research that suggests that goshawks depend on old-growth forest habitat. In the Goshawk Recommendations, they see just another excuse to cut big trees. Reynolds stands by the approach, though, claiming that generating saleable timber is an added bonus, not a driving objective.
Reynolds hoped that the research he's done would resolve this controversy once and for all. And the numbers do indicate that the Kaibab population is secure -- certainly not going extinct -- and that it fluctuates in response to shifts in prey populations on the Plateau. But the data also suggest that precipitation rates exert a greater influence on goshawk fitness than habitat structure. Without enough water to produce the pine cones that feed the squirrels that feed the goshawks, neither old-growth stands nor groups and clearings will support the Kaibab's hungry population. These preliminary results confound attempts to draw a neat cause-and-effect relationship between forest structure and goshawk health, but they reinforce Reynolds' commitment to managing forests to serve the prey species upon which goshawks depend.