The proposal of an initial human coastal migration into the New World during the late Pleistocene has gained considerable support in recent years. However, the methods of such a migration are not clear and the proposition that it was accompanied by seafaring around the North Pacific to access a kelp highway is still subject to debate. Recent discoveries now suggest that humans crossed Beringia into North America below the ice at least 17,000 years ago. Conversely, in southern California, people are not recorded on the ancient island of Santarosae any earlier than 13,000 years ago. In contrast, the use of seaworthy watercraft is evident only around 10,000 years ago when sea level inundation separated Santarosae into the four present-day islands of San Miguel, Santa Rosa, Santa Cruz, and Anacapa. At this time, early Holocene sea level rise appears to have stimulated watercraft technological innovations.