Both Africanized honey bees and European honey bees live in Rancho Palos Verdes, so if you are seeing a swarm or a hive on your property it is simply because they live in the same area as you.  Now, there is a distinction between a hive and a swarm that you need to be aware of:

• Swarms - A swarm of bees can be found on the branches in the trees, or just about any outdoor area.  Swarms take place when a colony outgrows the hive and splits.  Typically, a second queen leaves the hive and takes half of the colony with her.  Until they find a home, they will settle in one spot protecting the queen.  At this time the bees are fairly docile because they do not have a hive to protect.  Even Africanized honey bees aren’t aggressive at this point.
• Beehives - Beehives are the home of the colony.  This is where the queen lays her eggs.  The honeycomb is built in the hive and it is where the honey is produced.  Hives can be built in many places but typically they are built where they can be protected easily.  Hollowed out trees, wall cavities, between the walls of a home can all be homes to a hive.