A Mexican wolf born this month at a wildlife centre in suburban St. Louis is offering new hope for repopulating the endangered species through artificial insemination using frozen sperm.

The Mexican wolf population once roamed Mexico and the western U.S. in the thousands but was nearly wiped out by the 1970s, largely from decades of hunting, trapping and poisoning.

Commonly known as "El Lobos," the species, distinguished by a smaller, more narrow skull and its grey and brown colouring, was designated an endangered species in 1976.

Even today, only 130 Mexican wolves live in the wild and another 220 live in captivity, including 20 at the Endangered Wolf Centre in Eureka,

Missouri. A litter of Mexican wolves was conceived by artificial insemination in Mexico in 2014. But the birth on April 2 at the Missouri centre was the first-ever for the breed using frozen semen.