In 2002, Dr. Peter Moyle, an eminent professor of fish biology at UC Davis, and a specialist in California's native fish, sketched the known range of the major California native species on topo maps.  These were digitized by his graduate student, Paul Randall (now a leading fish biologist in his own right), and published as a GIS database.  We've converted the trout species information to KMZ files, making it generally accessible for the first time. The species we've converted include:

• Golden trout (California's state fish)
• Lahontan and Paiute cutthroat trout
• Coastal rainbow trout
• Eagle Lake rainbow trout
• Goose Lake redband
• McCloud River redband
• Kern River rainbow and Little Kern golden trout
• Warner Valley redband

You can download a zip archive of the entire dataset from the ">CA Downloads" link in the "CA Resources" menu in the sidebar.

Clearly, these data are somewhat "old school", and newer datasets are becoming available that duplicate some of this information with (possibly) more precise information.

But I'd want to know what one of the most eminent fish biologists in California thought about this stuff before I went out, wouldn't you?