A new method for censusing animal populations: The number of Eciton burchelli army ant colonies on Barro Colorado Island, Panama.

A new technique for estimating the size of an animal population is described. This technique is used to provide an up to date estimate of the number of colonies of the army ant Eciton burchelli on Barro Colorado Island, Panama. There have been approximately 50 colonies of this species on Barro Colorado Island for more than thirty years. The relative constancy of this population is contrasted with the great temporal variability of other tropical insect populations.