Plants, Lizards, and Ants

My independent project was focused on Short Horned Lizards and the microhabitats that they live in. These small lizards have limited home ranges that often span less than 100 meters. Short Horned Lizards on the property appear to cluster around certain areas, being notably absent across wide stretches of land. My question, then, was: are these sites chosen based on habitat structure or proximity to preferred food sources? Because sparse sagebrush communities are so common on the property, I expected them to congregate around specific ant communities.

My first day on the property I planned on locating two sites with lizards present, two sites without but on the same geologic formation (The Morrison), and one control. Unfortunately, despite hours of searching, I was only able to locate one lizard site, so my comparative study had to be changed. To reduce variability in my small sample size, I chose a site similar in vegetation and soil composition to where I found the lizard and a control farther away. At my three sites, a 25-meter diameter circle was set up, and vegetative data was collected with five Daubenmire frames: one at the center and four halfway to the perimeter in each direction. Also, total sagebrush was counted, and a general ground cover estimate was made. On the spots where I did the Daubenmire frames, I dug a small hole for a pitfall trap with a plastic cup and covered them with saranwrap to avoid catching anything through the day. The next day consisted of uncovering and monitoring the pitfall traps over the four hours that each was left open. Captured invertebrates were identified to morphospecies, counted, and released. Now that the data has been collected, I need to test significance of disparities in insect and plant community composition to quantitatively show if Short Horned Lizards choose their home sites based on local insect composition.

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