Survival for some endangered species hinges on 'Frozen Zoo'

ESCONDIDO, Calif. – San Diego Zoo officials say the survival of the northern white rhinoceros and dozens of other species could hinge on their gene bank, known as The Frozen Zoo.

For nearly 40 years, researchers have raced out whenever an endangered animal dies to collect its eggs, sperm or a bit of tissue to freeze in nitrogen-filled tanks for genetic research.

The collection amassed over nearly 40 years that has become the largest gene bank of its kind.

The Frozen Zoo's work has taken on renewed urgency since the San Diego Safari Park lost a northern white in December. There are only five left. All are unable to reproduce.

Scientists hope to utilize frozen sperm to produce another one.

The icy vials may someday even be used to resurrect recently extinct animals.