Great Bend of the Gila National Monument Establishment Act This bill establishes the Great Bend of the Gila National Monument in Arizona. The Department of the Interior shall: (1) conduct an inventory of invasive plant species in the Monument, (2).develop a management plan for the Monument in government-to-government consultation with Indian tribes having a cultural or historic tie to the Great Bend of the Gila, and (3) allow scientific research within the Monument, including research for the preservation of its historic and cultural resources. Interior may: (1) carry out vegetation management treatments within the Monument, including efforts to control salt cedar and other invasive plant species; and (2) conduct, or authorize other persons to conduct, research regarding the effects of climate change on the Monument's resources.