Two herons—one chalky blue, the other snowy white—lift from the reeds beside a gravel road running along the levee. On the other side, a lone mallard lands with a skid on the surface of the Santa Fe Canal, which is filled with water pumped from the Sacramento-San Joaquin River Delta. As Ric Ortega steers his white pickup along these marshy wetlands southeast of Mount Hamilton, he says the patchwork of canals, tule clusters, and grassy bogs comes alive with clouds of birds in the fall, when ducks and geese are migrating south from Canada.