6 white rhinos arrive in San Diego to be surrogate mothers

In this Dec. 31, 2014, file photo, Nola, a 40-year-old northern white rhino who is only one of five remaining of the species, wanders around her enclosure at the San Diego Zoo Safari Park on a cold winter day in Escondido, California. Six female southern white rhinos arrived on a chartered MD11 flight from South Africa landed at the San Diego International Airport on Thursday, Nov. 5, 2015. San Diego Zoo Global has one of the most successful rhino breeding programs in the world. To date, a total of 94 southern white rhinos, 68 greater one-horned rhinos and 14 black rhinos have been born at the San Diego Zoo Safari Park. AP FILE PHOTO

SAN DIEGO, California — The San Diego Zoo has welcomed six white rhinos from South Africa.

The six female southern white rhinos are part of the zoo’s efforts to save the critically endangered northern white rhino. There are just four northern white rhinos left in the world.

The zoo said Friday that the six southern white rhinos will act as surrogate mothers. They’ll be implanted with northern white rhino embryos in hopes of saving the subspecies, which has been decimated by poachers.

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Researchers are hoping a northern white rhino calf could be born from a surrogate within 10 to 15 years.

The six southern white rhinos arrived to the zoo Thursday after a 22-hour flight from Johannesburg. They were transported in individual crates and unloaded into fenced yards for a 30-day quarantine.