At work, at housing camps and in bars and restaurants, men have been left to mingle with their own. High heels and skirts are as rare around here as veggie burgers. Some men liken the environment to the military or prison.

“It’s bad, dude,” said Jon Kenworthy, 22, who moved to Williston from Indiana in early December. “I was talking to my buddy here. I told him I was going to import from Indiana because there’s nothing here.”

This has complicated life for women in the region as well.

Many said they felt unsafe. Several said they could not even shop at the local Walmart without men following them through the store. Girls’ night out usually becomes an exercise in fending off obnoxious, overzealous suitors who often flaunt their newfound wealth.

“So many people look at you like you’re a piece of meat,” said Megan Dye, 28, a nearly lifelong Williston resident. “It’s disgusting. It’s gross.”

Prosecutors and the police note an increase in crimes against women, including domestic and sexual assaults. “There are people arriving in North Dakota every day from other places around the country who do not respect the people or laws of North Dakota,” said Ariston E. Johnson, the deputy state’s attorney in neighboring McKenzie County, in an e-mail.