This number includes funds provided via the Mitchell Act (16USC 755-757; 52 Stat. The Mitchell Act specifically directs establishment of salmon hatcheries, file conduct of engineering and biological surveys and experiments, and the installation of fish protective devices. The major objective of this program has traditionally been to mitigate the negative effects of lost salmon habitat caused primarily by the building of dams for hydroelectric power, and also by other factors, such as agricultural runoffs, logging, and urban development. Over the years, Mitchell Act hatchery production has changed to meet two other objectives. First, some hatchery production has shifted to areas above the Bonneville Dam in order to provide harvestable salmon under the Columbia River Treaty Indian "IYust. Second, a portion of the hatcheiy production is being shifted to fulfil a conservation role in preserving endangered salmon stocks (captive breed) and supplementing their recovery.