THE DIET AND ECOLOGY OF HAWAIIS EXTINCT FLIGHTLESS WATERFOWL - EVIDENCE FROM COPROLITES

Ar least five species of large flightless waterfowl have become extinc t in the Hawaiian Islands in recent millennia. These birds are thought to have occupied the role of large herbivores in a wide range of terr estrial habitats. A collection of coprolites from one of the species ( Thambetochen chauliodous) was obtained during excavations in Holocene cave sediments on the island of Maui. The chemical composition and pol len and spore content of the coprolites ale analysed and compared with pollen/spore spectra from the cave sediments and from recent goose se als. The results support the contention that these birds were primaril y folivorous, and further suggest that ferns were important in the die t. The coprolites have a very fine texture that may result from effici ent hindgut fermentation and digestion of plant fibre. Our data are di scussed in the light of a recent hypothesis of plant/herbivore coevolu tion between extinct avian herbivores and native Hawaiian lobelias. Th e loss of large native herbivores, as well as other changes in vertebr ate trophic structure due to extinctions over the past few thousand ye ars, may still be affecting ecological processes in areas of the Hawai ian islands with native vegetation. (C) 1997 The Linnean Society of Lo ndon.