The Gianella Bridge spans the Sacramento River in Hamilton City, California. The bridge, which was built between 1908 and 1911, is part of CA Highway 32 and connects Glenn County and Butte County. Each fall threatened North American green sturgeons migrate southward in the river to the brackish waters of the San Francisco Bay. There, the bottom opportunistic predators feast on clams and shrimp before continuing along the West Coast as far south as Baja, Mexico or as far north as Alaska before returning to the Sacramento River every three to five years to spawn. The U.S. Army Corps of Engineers Sacramento District Planning Division has inserted telemetric tags in 85 green sturgeons over the past four years, which is helping them gather behavior data on the ancient fish species. The data is then analyzed to determine the degree of impacts USACE civil works projects may or may not have on the species that since 2006 has been listed as threatened under the Endangered Species Act. (U.S. Army photo by Ken Wright)