500
Give the main idea of this paragraph:
Three hundred years ago, there were 15,000 Kwakiutl. Today, there are only about 4,000. Many of the people work in logging, constuction, or fishing. They practice many of their old customs, such as potlatches, but also live in modern houses and go to see medical doctors.
What is "the Kwakiutl keep some old traditions but also have modern customs"?