They hear them
They memorized a map
They smell them
They dig at random until they find one
400
1000
10
4000
To hide from birds that would eat them
To make a nest for their young
To make a burrow to keep themselves cool in the summer
To find food underground
Even native bees that can sting rarely sting people unless you scare or hurt them.
On flowers
In underground cells
In honeycombs
In the bark of trees
All of the above
Look for them places with many flowers
Be patient and observe them
Do not be afraid of them
To find females to mate with
Most of the native bees in North America have already been studied.
An egg
Nectar and pollen
A waxy coating along the inside