Believed Extinct. Navassa Island was visited in 1966 and 1967 and no animals were present. An entomologist visited the island again in 1986 and saw no signs of any iguanas although he was not specifically looking for them. An extensive search again in 1999 failed to find any iguanas. Military occupation of the island prior to the 1960's was apparently responsible for its extirpation. A very slim possibility exists that some specimens may remain in captivity somewhere in the world but they would certainly be aged.