In addition to library databases (like ProQuest) and free article indexes (like Google Scholar), several US Government agencies provide freely available indexes to their own publications.
Ma, M. (2015, August 24). Power Lines Restrict Sage Grouse Movement in Washington. Retrieved from UW News: https://www.washington.edu/news/2015/08/24/power-lines-restrict-sage-grouse-movement-in-washington/