The adzebills (Aptornithidae) were an ancient endemic lineage of large flightless Gruiformes that became extinct shortly after Polynesian settlement of New Zealand. The diet and ecology of these enigmatic birds has long been a matter for conjecture, but recent stable isotope analyses of bones of the North Island adzebill (Aptornis otidiformis) have indicated that adzebills may have been predatory. Here, we add to our understanding of adzebill ecology by providing the first stable isotope analyses of South Island adzebill (A. defossor) bones from two Holocene deposits.
Pollen analysis of a high altitude bog (Winterton Bog) and an alluvial soil sequence in the upper Awatere catchment on the western flanks of the Inland Kaikoura Range, and radiocarbon dates on wood and charcoal from the Marlborough region, have established a Holocene, (post 10 000 years B.P.) vegetation history for this area.
During the Late Holocene (1800 years BP to the present day) there have been three depositional episodes in coastal sand dune areas: Tamatean (1800 to 450 years BP), Ohuan (450 to 150 years BP) and Hoatan (150 years BP to the present day). Each episode comprised two phases: an unstable phase with a high rate of deposition, followed by a stable phase with a low rate of deposition and soil formation.