Apologies if this is a duplicate - wasn't able to find anything similar.
Making a 3gal batch of strawberry wine. Poured sugar-water over fruit and set aside to cool. Been having problems with bugs so I put the lid tight on bucket. Anyway, life got ahead of me and forgot about the wine for two days. Ran back to my bucket, opened the lid and was very surprised to see that the fruit had started fermenting without me! Strawberries were clearly into primary fermentation already. Fearing I would lose the wine, I added my yeast. 2 days later and things seem to be okay; primary is still going strong and must seems to be happy.
In doing research, it appears I stumbled into "young country wine" making, but all of the directions say to leave the bucket uncovered. My lid was tightly-closed, creating a secondary-like environment.
I've read there are natural yeasts on the fruit and in the air, but I removed the air.
Question Can anyone explain what happened?