Point-didn't realize Spain's navy was that small.
Still, the Russians have the same problem, and Spain controls the entire west coast of South America and Mexico-they can send ships around Cape Horn and then north, stopping in Buenos Aires, Valprisario, Lima etc. for resupply. Russia, by contrast, would probably have to stay away from Spanish holdings as much as possible, with means going around Africa, through the Indian ocean, and up the Chinese coast-with no resupply for this entire distance unless Britain or the Netherlands decide to be friendly.
So again, considering that the Nootka Crisis could happen in 1789, I think Spain would make a big stink about Russia trying to settle California-but for the reasons above, I think an actual war would be a difficult, resource-intensive thing both countries would want to avoid, and thus you'd get some kind of compromise-probably giving the Russians some of northern California, and the rest to the Spanish.
I think if we assume Russia is in a position for this to be a serious issue, we have to assume Russia is in a better position than OTL in regards to ships and supplies or Russia won't be able to establish a presence worth reporting to Spain in the first place.
Well, consider that, IOTL, Spain didn't seriously start trying to populate California till around the American Revolution. Here-seen as how the Russians might conceivably move into California if it stays empty-they're probably going to start 30-50 years before then-founding a network of forts and missions along the coast, and offering land grants and other encouragement to anyone willing to come to them (not only from South America, but Spain itself, the rest of Europe and the Phillipenes as well-I expect the new colony might have a large Asian population, at least at first). It probably won't get hugely populated at first-but then again, neither will Russian America.
The problem is that Spain can try all it likes, but that doesn't make people enthusiastic about coming there.
And with all this activity in California, the likelyhood of someone finding the gold increases-and if we go with "north of San Francisco Bay" as the border, that would, IIRC, put it right on top of the goldfields, which could get very interesting...
I don't have a map handy, but I think they're split.
BlondieBC: But for Spain?