"In order for Britain to spend all this money here, there has to be a viable population."

It is intended to release a total of sixty birds, to ensure a viable population.

For a viable population both genders must be present.

This forest is one of the last areas large enough to support a viable population of elephants.

Genetically viable populations are generally taken to mean those with a minimum of 20 individuals.

For a viable population should have copies of both genders.

Success in the form of a population viable for future re-wilding is only to be accomplished with difficulty from the start.

You can't have a viable breeding population with only a tenth of the adults fertile!

Only a few viable populations remain, widely scattered in region.

Sometimes the habitat has to be restored to maintain a viable population of a particular species.