THE DALLES, Ore. (AP) — Two Pacific Northwest tribes on Monday demanded the removal of three major hydroelectric dams on the Columbia River to save migrating salmon and starving orcas and restore fishing sites that were guaranteed to the tribes in a treaty more than 150 years ago.

The Yakama and Lummi nations made the demand of the U.S. government on Indigenous Peoples Day, a designation that's part of a trend to move away from a holiday honoring Christopher Columbus.

For decades, people have debated whether to remove four big dams on the Lower Snake River, a tributary of the Columbia, but bre...