Ecology and breeding colors of the side - blotched lizard ( Uta stansburiana ) in the Grand Canyon by Robert Schell and Jessica Dettman

The side-blotched lizard (Uta stansburiana) is one of the most common lizards along the Colorado River corridor through the Grand Canyon (Warren and Schwalbe 1986). During our trip down the river, we saw numerous side-blotched lizards, despite the cold spring weather; they were by far the most frequently observed lizard species. Their colors were variable and bright, including shades of brown, gray, white and blue dorsally; with whites, blues, oranges, and yellows ventrally (Fig. 1 and 2). Past studies have shown that these lizards are most abundant in the lower riparian zones (new high water zone and fluctuation zone) (Warren and Schwalbe 1986); however we found that they were widespread throughout the riparian zone, and even above the riparian corridor. Our qualitative observations suggest that the side-blotched lizard may not rely as heavily on the lower riparian zones as past studies suggest, but rather that it utilizes all parts of the riparian habitat. In fact, these lizards seemed to possess a broad habitat preference, and were found practically everywhere we went in the canyon.