Farewell Spit, at the northern extremity of the South Island, shelters the quiescent Golden Bay to the east, the wetlands of which are an internationally-significant habitat for over 80 species of wetland birds including several internationally-migrating species. Gazetted as a Protected Area since 1938, the majority of Farewell Spit is accessible by permit only and tourist traffic to the lighthouse at the far end of the spit is carefully managed to keep impacts to a minimum.
Farewell Spit has been built up from sand deposits carried north along the South Island West Coast over the course of approximately 6500 years. Presently about 35 kilometres long, Farewell Spit continues to receive an average of approximately 2.2 million cubic metres of sand each year and is still extending at a rate of about 15 metres per year as a result. In addition to the transport of sand along the northern shores of Farewell Spit by longshore currents, huge volumes of surface sand are also blown across the spit towards Golden Bay to form extensive dunefields directly above the beach. These dunefields are exposed to strong winds from virtually every direction, especially from the west.
Dune vegetation on Farewell Spit is dominated by exotic Marram grass (Ammophila arenaria), although the native Pingao (Desmoschoenus spiralis) is believed to be making a comeback in recent times following the removal of grazing cattle from the spit. Active dunefields are characterised by classic crescent-shaped ‘barchan’ dunes, often separated from each other by small dune lakes or patches of quicksand.
The dune in this photograph is an example of an old eroded dune, topped by Marram grass, that is slowly being buried by a freshly-rippled barchan dune as westerly winds continue to bring in sand from the distant beach.
