Greater sage-grouse (Centrocercus urophasianus), a species of conservation concern, inhabits the western United States where it selectively browses on sagebrush. Sage-grouse browse preferentially on Artemisia nova and avoid Artemisia tridentata ssp. Wyomingensis which may differ in their chemical defenses including polyphenols. Polyphenols are aromatic compounds produced in sagebrush which influence detoxification pathways and cellular signaling in herbivores. We hypothesized that certain polyphenolic compounds deter sage grouse, which accounts for dietary preferences for Artemisia nova over A. t. wyomingensis by sage-grouse. We found that the total polyphenolic content of A. t. wyomingensis was higher than A. nova. Using reverse phase high performance liquid chromatography (HPLC), the same number of individual polyphenols was found in both species. However, 12/36 polyphenols were found at higher concentrations in A. t. wyomingensis, which may account for sage-grouse avoidance. By better understanding sage-grouse dietary preferences, it may be possible to conserve and restore sagebrush that are of the highest dietary quality. Additionally, diet selection by sage-grouse may direct us to new bioactive polyphenols that may be used in the development of new medications or therapies.

The role of polyphenols of Artemisia nova and Artemisia wyomingensis in sage grouse dietary preferences