Historical Degradation and Ecological Recovery

Spanish arrival to Alta and Baja California in AD 1542 marked the beginning of widespread ecological changes for California Island ecosystems. Over several centuries, Native peoples were removed to mainland towns and missions, intensive commercial fisheries and ranching operations developed, and numerous exotic plants and animals were introduced. The ecological fallout was swift and extensive, with extinctions and extirpations, devegetation, severe soil erosion, damaged hydrology, collapsed fisheries, and other ecological impacts. Archaeologists have long recognized some of the effects of these historical impacts, but only after decades of restoration biology on the islands have we come to appreciate how dramatically ecological baselines have shifted since Spanish arrival. As a result, many of California's islands now appear to have been optimal rather than marginal for human occupation.