Hobbies And Interests
Appearance
This small bird had the traditional morphology of extant sandpipers. It is believed to be closely related to P. leucoptera, another extinct sandpiper of the same genus. Notable features described by Anderson include several characteristics distinguishing the two species. P. ellisi had no white spot caudal to its eye, its wings had two white bars, rather than one and its legs were believed to be yellow. P. ellisi was generally lighter in color than P. leucoptera.
Range
The limited information collected about this now-extinct bird makes it difficult to determine its former geographic range. P. ellisi existed on Moorea and it likely existed on other islands, including Tahiti, Bora Bora and small atolls with its flight range. The extant species in this genus has a historical range extending throughout the Tuamotu Archipelago. This archipelago is east of Tahiti and contains hundreds of small islands and atolls. It is likely that P. ellisi once shared a similar range.
Taxonomy and Ecology
The white-winged sandpiper belonged to the Order charadriiformes, a global group of birds including sandpipers, gulls, plovers and other small shoreline birds. Within this diverse group, sandpipers receive their own taxonomic family, Scolopacidae. These birds, including P. ellisi, are omnivorous, eating primarily invertebrates such as shellfish, insects and annelids, but opportunistically eating certain plants and the occasional small vertebrate, fish and amphibians. The white-winged sandpiper's closest living relative, the Tuamotu sandpiper, is found from shorelines to forest edges, where it preys on invertebrates and occasionally practices herbivory.
Cause of Extinction
Like most birds living on remote Pacific islands, P. ellisi evolved with no mammalian interactions of any kind. The difficulties of successfully traveling to such small and remote islands preclude mammals from establishing viable populations at these places. As a result, the habits of these species do not include defenses against mammal predation. When explorers visited places like French Polynesia in the 18th century, they unknowingly introduced mammals such as cats and rats to the island ecosystem. These introduced animals easily hunted and exterminated many bird species by attacking the birds directly or eating their eggs, and by destroying the vegetation used by the birds for habitat. P. ellisi became extinct by the end of the 18th century as a result of the introduction of mammals to its range of islands.