A series of 18 fossil beetle assemblages are used to reconstruct the paleoenvironment of the northwest West Coast, New Zealand, over the period of the last interstadial–stadial transition (ca. 37,000–21,300 cal yr BP). The samples were recovered from an in-filled hollow within a dune field ca. 9 km south west of Westport (41°47′S, 171°30′E). This fossil beetle reconstruction is compared to an existing palynological reconstruction from the same site. The beetle assemblages indicate an environment of marshy shrubland interspersed with closed canopy coastal vegetation prior to glacial onset, and a mosaic of closed canopy patches and open tussock grassland during full glacial conditions. These interpretations, contrast with the palynologically based interpretation which indicates subalpine shrubland prior to glacial onset and widespread grassland with little woody vegetation during the period of maximum glacial cooling. This study is consistent with other non-pollen studies in New Zealand and indicates that the palynological interpretation of the paleoenvironment of the Westport region downplays the importance of closed canopy vegetation in the area during the transition from interstadial to full glacial (stadial) conditions. It challenges the interpretation of open vegetation at low elevations during glacial periods from pollen studies.

A fossil beetle study is presented from the northwest coast, South Island, New Zealand. The samples were recovered from overbank deposits on a marine terrace situated 4 km east of Westport, New Zealand (418 45' S, 1718 36' E). The age of the site is constrained to between 74 and 40 ka but discrepancies between luminescence and radiocarbon age results prevent more precise age control.The older of two samples indicates a closed canopy Nothofagus (southern beech) forest with deep litter and dead wood on the forest floor. The younger sample yields a similar Nothofagus forest environment with subalpine affinities and nearby tussock grassland. For the older sample, mean summer and winter minimum temperatures were similar to modern values. Mean summer temperature was ca. 3.08C cooler than modern during the younger phase while mean minimum winter temperature was ca. 5.08C cooler than present indicating both cooling and increased seasonality. Both samples suggest a 30-40% decrease in mean annual precipitation from modern values.Persistence of closed canopy Nothofagus forest during the period of 74-40 ka contrasts with regional pollen studies which imply widespread shrub-land at these times. This implies that this site may have served as a glacial refugium for Nothofagus forest.

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