What staff members are needed to run animal shelter?

Your lowest number could be one person.

That person would need to know alot about running a shelter. For example, they would need to limit the hours that the shelter is open so they could go home at night, and would need to know the legality behind creating a non-profit organization (if that is the premise for the shelter).

They would also need access to a great deal of money to pay overhead costs like rent, electricity, advertising, insurance, food, and veterinary care.