The main types of ecosystem MOWS are concerned with in terms of restoration and conservation work, are sand dunes and wetlands.
Sand dunes are critically endangered ecosystems, supporting a wide variety of specialist native flora and fauna (Jamieson, 2010). They have declined significantly in the past century, partly due to coastal development and exotic invasions. They are natures’ flood defence system, allowing sand to be dragged out during a storm to create sandbars, which reduce the power of the waves hitting the beach. The sand is then gradually returned to the beach and the dunes build up again over time. This process is negatively affected by the use of marram grass (Ammophilia arenaria) to stabilise dunes. This European grass creates a steep dune profile, causing storm waves to gouge out the front of the dune, leaving an almost vertical face which takes a long time to repair itself. In contrast, native grasses such as spinifex (Spinifex sericeus) and pingao (Ficinia spiralis) result in a shallower gradient and allow dunes to rebuild in a shorter space of time.
Wetlands are natures’ filters; sifting harmful substances from the water, as well as protecting against floods and erosion. They provide habitat and food for many species, and recreational areas for activities such as fishing and tramping.
The dominant vegetation on the fore dunes are the native grasses spinifex (Spinifex sericeus), pingao (Ficinia spiralis) and sand tussock (Austrofestuca littoralis). These fore dune plants are well adapted to the dynamic environment, tolerating high temperatures, low moisture conditions, salt spray and burial by sand (Esler, 1970). These species are in good condition on the spit but are threatened by invasive pest plant species and rabbits. The back dune is dominated by pohuehue (Muhlenbeckia complexa) and wiwi (Juncus pallidus).
References: Esler, A. E. (1970). Manawatu sand dune vegetation. Proceedings of the New Zealand Ecological Society, 17: 41-46.
BirdLife International (2012). Charadrius obscurus. In: IUCN 2012. IUCN Red List of Threatened Species. Version 2012.1. . Downloaded on 03 August 2012.
Jamieson, S. L. (2010). Sand dune restoration in New Zealand: Methods, Motives, and Monitoring. Unpublished MSc Thesis. Victoria Universityof Wellington, Wellington, New Zealand. 158p.