DOURADOS, Brazil (AP) _ When Silvinha Cavalcante, a Kaiowa Indian, didn't return to her straw-roofed hut one evening last April, Luciano Arevalo knew where to find his 12-year-old niece.

He crossed the dusty plain of his reservation where a forest once stood and stopped at the foot of a lone guava tree. It was there that Silvinha's widowed mother had hanged herself a year earlier.

From a branch a girl in a sundress dangled by the neck, her body swinging in the moonlight.

``Silvinha went to her mother,'' said Arevalo. ``She had eight baby brothers. They were going hungry, and she could not bear to watch this. It was killing her soul. To save her soul, she killed her body.''

Suicide, once rare among Brazil's native Indians, is ravaging the Guarani-Kaiowa tribe that lives on the remote brushlands of the western frontier state of Mato Grosso do Sul.

In the first nine months of this year, 43 Guarani-Kaiowas killed themselves and dozens of others tried, according to the government's National Indian Foundation, known by its Portuguese acronym, FUNAI.

That is nearly double the average of 23 suicides in each of the four preceding years. And before the 1990s, only a handful of the tribe's 25,000 members killed themselves each year. By contrast, the suicide rate for Brazil as a whole is less than one for every 25,000 people, the census agency says.

An especially troubling aspect is that 40 percent of the tribe's suicides this year have been girls under 16, FUNAI says. Only about 2.5 percent of the nation's total suicides involve young girls.

Experts say they do not have good statistics for Brazil's Indians but they sense that the Guarani-Kaiowa situation is much worse than for other tribes.

``What we are dealing with is a culture in crisis,'' Otilia Nogueira, a Guarani-Kaiowa specialist for FUNAI, said in an interview in Brasilia, the capital.

Indian experts attribute the phenomenon to poverty, the disintegration of families and forced acculturation of the Guarani-Kaiowa in the face of a violent westward push by white settlers, an encroachment similar to that on North American tribes a century ago.

Anthropologists also blame the clearing of forests for pasture and plantations and the loss of more than half of the tribe's ancestral lands to ranchers and farmers.

``To resist giving up their identity, the Guarani-Kaiowa appear to see no alternative but death,'' said Rubem Thomaz de Almeida, an anthropologist who has studied the tribe since 1973. ``It's not only a disgrace, but the shame of a country that likes to call itself the most racially integrated nation on the planet.''

Fewer than 300,000 Brazilian Indians are left today, down from an estimated 5 million when Portuguese explorers arrived in 1500.

The Guarani and Kaiowa then were separate, nomadic tribes, their villages stretching 1,500 miles from the Atlantic Ocean into what is now Paraguay.

About 50 years ago, white settlers began moving west and expelling Indians by violence or by obtaining questionable land titles, often from corrupt territorial judges. The two tribes were lumped together and isolated on tiny ``island'' reservations in Mato Grosso do Sul.

In 1978, FUNAI secured bank loans on behalf of the tribe for mechanized farm equipment and offered as collateral hardwood trees on the reservations.

With no farm training or understanding of planting for profit, the Indians went bankrupt in two years. FUNAI divided the reservations into lots and authorized the cutting and sale of hardwoods.

Today, about 25,000 Guarani-Kaiowa survive in 22 villages scattered over 68,000 acres of largely deforested scrubland. The fragmented reservations are so small they cannot support even subsistence farming.

``Our sorrows begin with the lack of land,'' Chief Amilton Lopes and seven other Guarani-Kaiowa leaders wrote in a letter to Congress earlier this year. ``There is not enough space to plant, hunt or live.''

The problem is most severe near Dourados, a boomtown of 80,000 people that has grown rich on cattle ranching and soybeans.

Here, 9,065 Indians live on 8,750 acres of scrubland. Gone are the animals, fish and forest that once sustained their villages. The soil is parched and sapped of nutrients.

Extended families are crammed into one-room lean-tos and ramshackle huts of scrap wood, mud and brick. They have no running water or electricity, only mud floors and kerosene lamps.

With few prospects, boys as young as 10 leave to earn the equivalent of $20 a week as migrant farm laborers, cowhands or sugar cane cutters for the state's many alcohol distilleries.

Human rights groups say some Indians are lured into forced labor camps on plantations, sawmills, charcoal-producing furnaces and shoe factories.

Guarani-Kaiowa girls, who normally would marry and start families by age 14, are left without potential mates. Many drop out of school to care for their siblings or join their mothers picking crops for meager pay.

By 15, many girls flee to Dourados to work in strip clubs or as maids in hotels. Some are kidnapped to work in brothels in remote gold camps.

Alcoholism and drug use are on the rise, and many Guarani-Kaiowa say those who commit suicide often kill themselves while drunk.

``We have learned the white man's evils,'' said Teodoro Rodrigues, a Guarani-Kaiowa in Bororo village, where nine Indians have killed themselves this year. ``Alcohol only helps to lose the soul, but we have lost control.''