a wasp
An animal that looks like a wasp and builds its home from mud is called a mud dauber. They are generally harmless to humans but will sting when they feel threatened.
If referring to the nest of a Mud Wasp, then about the size of a soccer ball
The European paper wasp makes its nest out of mud.
Mud daubers are a variety of wasp which build their nests out of mud or use the nests of other species of wasp. Mud daubers which survive the cold months are immature individuals which spend the Winter in the nest.
Mud dauber wasp only has one predator and that is the bird.
A wasp is in the genus Hymenopera, family Vespidae
the class is insecta
Yes - there are many types of wasps in California including: German yellowjacket, western yellowjacket, California yellowjacket, paper wasp, mud dauber, fig wasp, Western sand wasp, square headed wasp, bee wolf, Pacific burrowing wasp, gall wasp, soldier wasp, club horned wasp, burrowing wasp, blue mud wasp, cutworm wasp, thread-waisted wasp, mason wasp, potter wasp, and pollen wasp. Obviously this is not a complete list - just scratching the surface really - but it does demonstrate that California has plenty of wasps.
10 years
Assuming I understand your question, it's not a bee. It's a mud dauber -- a type of wasp.
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