My Portal story begins in 1991 when Jim Brown offered me the opportunity to be the Portal postdoc. Among other things, this meant I organized the yearly ant census in which we spent about 2 weeks counting the abundance of ant colonies on the experimental plots. In one of my first summers, I hired Don Sias to help with the census. Don was a non-traditional student and had previously traveled extensively throughout the southwest. One day he mentioned to me that the vegetation in the San Simon valley looked pretty “beat up”. By that he meant the vegetation, dominated by shrubs, had the look of a grassland that had become desertified.

I was intrigued by Don’s comment for two reasons. First, Brown and Heske (1990) had recently described a significant increase in grass cover on Portal plots that removed kangaroo rats and mentioned that the site was “near the zone…