Solow, A.R. J. Math. Biol. (1993) 32: 79. doi:10.1007/BF00160376
This note describes a test for extinction in a declining population based on a record of sightings. The test assumes that, prior to extinction, the sightings follow a Poisson process with decreasing rate function. An application to a sighting record of the black-footed ferret is presented.