However, it is entirely likely that (given the non-migrant nature of the species) the populations, some 2000 miles separated from each other, would constitute separate subspecies. In this case, the Tuamotu subspecies would be called "Prosobonia cancellata parvirostris", while the Kiribati population would be the nominate subspecies, " P. c. cancellata" (Kiritimati sandpiper). The Kiritimati population became extinct some time in the first half of the 19th century or possibly later due to introduced predators. These might have been black rats ("Rattus rattus"); as these were only temporarily present on Kiritimati and perhaps did not arrive until the 20th century, the feral cats which started to overrun the island in the 19th century make more likely culprits.