The zoo says this an indication the Species Survival Plan is working.Henry Doorly Zoo & Aquarium's giraffe Zola is expecting a baby this Spring.Jason Herrick the Vice President of Conservation and Animal Health said over the years SSP has made enough breeding recommendations to keep the population where it is now, so the plan is right where it should be.Shandera said in order to create sustainable growth in the giraffe population, Henry Doorly works closely with other zoos."If we were to have the giraffe that we have here at Omaha and never make transfers or send or receive from other institutions that's not vey conducive to a sustainable population," he said."