Sonoran pronghorn (Antilocapra americana sonoriensis) are located exclusively in the Sonoran desert of Arizona and Mexico. They were abundant in the 1800s but have suffered a significant decline due to drought, habitat fragmentation and other environmental factors. It is important to understand the ecology of the population to develop adequate management practices. Currently, there does not appear to be a lot of information on the relationship between cortisol levels and chlorophyll levels, or even cortisol levels alone, which could be important information on how pronghorn are responding to current environmental conditions. The intention of this project is to address this possible relationship between cortisol and chlorophyll levels in pronghorn. Methods include using pronghorn fecal samples, a less invasive way to gather population information, collected from individuals at sampling sites. The collected fecal pellets are dried and pigment is extracted for analysis. Then, extracts are put through enzyme-linked immunosorbent assay (ELISA) testing to measure cortisol levels and chlorophyll levels are measured with a spectrophotometer. The data of both cortisol and chlorophyll is compiled for correlation testing.
Results/Conclusions
There appeared to be variation in the baseline levels in cortisol and chlorophyll levels among individual pronghorn. A positive correlation was found between the cortisol and chlorophyll levels. However, the relationship between the two is unclear as high quality forage areas (areas high in chlorophyll) can be associated with stressful environmental or social conditions. These conditions could be intraspecific competition around sampling sites as well as human disturbance.