The sand dunes of Kawakaputa Bay and Haldane Bay, Southland

The Conservation Estate, administered by the Department of Conservation (DOC), contains areas of land of undetermined conservation value. These include coastal lands, obtained and managed by the Government of the day for other than conservation purposes. One such purpose was to stabilise coastal sand dunes where drifting sands presented a hazard to adjacent railway lines or roads. The Sand Drift Act 1908 was enacted to facilitate this process. At Kawakaputa Bay approximately 60 ha of land was obtained by the Crown and planted in marram to protect the adjacent railway from drifting sands. These lands, today vegetated and semi-vegetated sand dunes, are currently grazed by sheep and cattle in accordance with a grazing concession. The character of the Kawakaputa Bay dunes is of interest to DOC (Southland) because of the potential to restore a mountain-to-the-sea landscape incorporating: the coastal dunes; adjacent remnant kamahi-broadleaf forest on former dunes; lakes; wetlands; and the plant and forest communities of the Longwood Range. The botany of the DOC lands has been described by Johnson (1984) but to date there has been no assessment of the distinctiveness of the coastal landforms present or the impact of grazing on these landforms. There is also interest in the potential to restore pingao (Desmoschoenus spiralis) should stock be removed from the dunes. A very similar situation exists at Haldane Bay in eastern Southland. At this location Crown land covers an area of approximately 144 ha and extends from the Haldane Bay foreshore to the "Reservoir" in the north and Blue Cod Bay in the east. As with Kawakaputa Bay the site has significant botanical values (Range 1995) but there has been no assessment of the character or geomorphic significance of the dunes. The purpose of the current study is, therefore, to: 1. provide a description of the landforms and processes at Kawakaputa Bay and Haldane Bay; 2. provide an assessment of the geomorphic distinctiveness and representativeness of the dune landforms at these locations; 3. evaluate the impact of landuse options (specifically, grazing and non-grazing); and 4. recommend management options for marram control and pingao restoration. 1 2. Landforms and geomorphic processes 2.1 ENVIRONMENTAL SETTING Kawakaputa Bay lies between Riverton and Te Waewae Bay on Foveaux Strait at latitude 46.5°S. Kawakaputa Bay, Colac Bay and Oreti Bays are defined by a series of headlands composed of gabbro-granitic rocks (Longwood Intrusives). Kawakaputa Bay is enclosed by Wakaputa Point to the …