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Vegetation in the Esperance Valley, Milford catchment, Fiordland, as it was in February and March 1974, is described using quantitative data for part of the valley that included home ranges of two male kakapo (Strigops habroptilus). One home range, of only 1.8 ha, was sited at 700 – 730 m altitude and extended over a gently-sloping river terrace covered in snow totara (Podocarpus nivalis) scrub with short silver beech (Nothofagus menziesii) forest at its margins. The other home range was 4 ha in area, sited on a very steep (42°) valley wall mantled with unconsolidated avalanche debris at 800-860 m altitude, faced NW and was covered by Blechnum capense fern – shrubland and short silver beech forest communities. At that time, this valley differed from most other parts of Fiordland: although possums (Trichosurus vulpecula), stoats (Mustela erminea) and rats (Rattus spp.) were present, ungulates were absent or very localised. Results gave no indication that food was limiting kakapo numbers in the Esperance Valley and we conclude that, because of the extreme vulnerability of females and their eggs, nestlings and fledglings to introduced mammalian predators, stoats were the most probable primary cause of kakapo decline in Fiordland.