 In 1970 Gillham took a sabbatical to carry out research on Aldabra Island (CORR) in the Seychelles; far out in the Indian Ocean and virtually isolated from human activity.The US military wanted to turn the island into an airbase, therefore Gillham was to report information about the island's wildlife back to the Royal Society and the Smithsonian Institution before building could commence.Gillham reported the importance of the island for sea birds, including Frigatebirds, as well as for the Aldabra giant tortoise, so the island was never built upon.