California Wild Heritage Act of 2003 - Designates specified national forest and Bureau of Land Management district lands in California as wilderness and components of the National Wilderness Preservation System (System). Requires such areas to be administered by the Secretary of the Interior or Agriculture, whichever has current administrative jurisdiction over each area.

Designates specified California public lands as: (1) salmon restoration areas; (2) wilderness study areas; and (3) potential wilderness areas.

Designates specified California national park lands as wilderness and components of the System, requiring such lands to be managed by the National Park Service.

Designates specified California rivers as wild and scenic rivers. Requires the review of two additional California rivers to determine their suitability as wild, scenic, or recreational rivers.

Establishes the Sacramento River National Conservation Area. Requires the development of a comprehensive plan for the long-range protection and management of such Area.

Establishes the Ancient Bristlecone Pine Forest for public enjoyment and scientific study. Requires the development of a comprehensive management plan for such Forest.