HELENA - Counties encompassing American Indian reservations - and the reservations themselves - hold Montana's youngest populations, and the pattern reflects social conditions among the state's largest minority, experts say.
Short lives plagued by illness, poor health care, alcoholism and drug use are the reason for the concentration of youth in and around reservations, they said.
"Indian populations don't tend to live as long because of factors such as health care availability," said Jim Sylvester, economist at the Montana Bureau of Business and Economic Research.
Stan Spotted Wolf, director of tribal social services on the Blackfeet Reservation, said many Indians live only to 50 or 55, far below the general population's life span of about 76.
Diabetes, drugs, alcohol and traffic crashes claim many lives, he said. Limited access to medical care for the elderly contributes to shortened lives, he added.
But the low median ages also reflect a tendency of youngsters to continue living on reservations because they are unable to afford education or find jobs elsewhere, Spotted Wolf said.
In a state where the median age last year was 37 1/2 year old, the seven counties with reservations had an average median age four years younger. Six of the 10 counties with median ages lower than the state were tied to reservations.
Big Horn County, home to the Crow Reservation, had the lowest median age at 29.8 years, which means half the people were older and half younger. Almost 40 percent of residents were under 20 and less than 9 percent had reached 65.
Tiny Boneau, with 190 residents, was the state's youngest community. The town near the southern edge of the Rocky's Boy Reservation in northcentral Montana had a median age of just 13. Nearly 40 percent were children less than 10 years old.
Of the 25 youngest populations, 17 were in communities on or near reservations.
Median ages on the reservations also were low, averaging 23 1/2 years old. The youngest was Rocky's Boy at just 20 1/2 years; the eldest was Flathead Reservation at 37 1/2 years.
The seven reservation counties had the state's highest percentage of households with single mothers. Spotted Wolf said it was an indicator of how drug and alcohol abuse have affected social behavior and led to more teen pregnancies on reservations.
The oldest population was St. Marie, a former Air Force base on the plains north of Glasgow that had been marketed as a military retirement community. The median age was 59.9 years and slightly more than a third of its 183 residents were at least 65 years old.