Where are you located? There are weather related problems in some parts of the country and this can affect the number of monarchs.
-Elisabeth

I am in Southern CA. I don't know what zone that is.

Here in Madison, Wisconsin, I find it difficult to impossible to actually observe a monarch caterpillar go all the way from egg to adult, out in the yard. If I want to see a healthy adult eclose, I have to find a milkweed leaf with an egg, and hand-rear, done with a glass mason jar, covered with a piece of fiberglass screen, held down with a rubber band. There are many monarch predators here: ants take the eggs and also smaller caterpillars, wasps take larger caterpillars, and there is a parasite fly that uses monarch caterpillars as a host for its young. Monarch cats can get infected with various microscopic predators, including viruses, bacteria, and protozoa. If you are growing considerable milkweed, my guess is that sooner or later the monarch predators will find your yard. If you decide to hand-rear, its best to bring the monarchs inside as eggs, because they will have had the smallest chance of being infected at that point in the life cycle. Milkweed leaves should be thoroughly washed in cold water, and dried, before being given to monarch cats as food. I'm happy for you that you were able to see adult monarchs emerge and fly off. I don't get to see that very often.

I've posted this before. Sometime in the '90s, I watched a monarch lay eggs all over my yard. I looked at a few but decided to gather them later cuz I was busy. Some hours later, I went to collect them but they were all gone. My guess was that the ants got them.

There are a zillion predators out there. The eggs are very vulnerable, just as the first and second instar cats are also very vulnerable. If you want them to grow up but also want them to do it as naturally as possible, I'd suggest you raise them in a protected environment until they are third instar. There are still plenty of predators that will still grab them but they will be too big for most ants, ladybugs and probably earwigs.

KC