The number of polygamists is growing throughout the Western United States, and most live in Utah, a researcher says.

"Polygamy is on the rise," said Cliff Craig, an associate professor at Utah State University. Craig spoke Friday while making a report to a session of the annual convention of the Association of American Geographers, which concluded Saturday.Craig said he believes 30,000 to 40,000 people could be practicing polygamy in the West, from southern Canada to northern Mexico. He estimated that 20,000 to 30,000 of those live in Utah alone.

He acknowledged it is difficult to determine the exact number of polygamists in the Western United States and that other estimates range from 10,000 to 50,000.

Craig said most are scattered through small towns and rural communities, with larger concentrations in places such as Colorado City, which is in the isolated Arizona Strip portion of northwestern Arizona.

Craig's talk was based on preliminary findings of research to identify changes in the practice of polygamy since 1887, when the federal Edmunds-Tucker Act outlawed it. Gary King, a University of New Mexico graduate student, assisted in the research.

Modern polygamy often is associated with "neo-fundamentalists" who attach political values to the practice of having more than wife, Craig said. The values generally are against taxes, public schools and big government and in favor of self-government and home schooling, he said.

The philosophy seems to be based on a wish to "let me do my own thing," he said.

The new form of polygamy is much different from the traditional form of the 19th century, which was based on deep-seated religious values more than on political ones, Craig said.

The Church of Jesus Christ of Latter-day Saints renounced plural marriage in 1890.

Almost nothing is done by state or federal officials to stop the practice of polygamy, and in some cases community leaders who do not practice polygamy have been sympathetic to those who do, he said.

"State and federal laws have been nearly impossible to enforce against polygamists due in large part to the unique cultural composition of the region in which it is practiced," Craig wrote in a summary of his report.

"Both media sensationalism and a concerted effort by some community leaders to keep the issue quiet have combined to present a skewed public understanding of the practice of polygamy," he said.