dweste,

Can you explain what you mean by this. How it works. Or, some
examples.

"migrate to best harvest areas with the opportunities / seasons"

Wheat and grain harvesters move northward each season and
harvest wheat for farmers. Few jobs. Highly mechanized.

Migrant farm laborers, fruit and vegetable pickers move around
as needed. Hard work. Lots of poor people to compete with
you. I flash on "Grapes of Wrath" by John Steinbeck.

It is really hard for me to think of good examples of this;
but I guess if you were starving, you would try anything.