Restoration of estuarine ecosystems

Estuarine restoration research is relatively new in New Zealand and has been largely instigated by community groups that have become increasingly concerned with the decline of plant and animal species.

Whaingaroa (Raglan) estuary. Photo: Alastair Senior

Estuaries are semi-enclosed bodies of water, where freshwater from rivers and streams meet and mix with seawater from the ocean. Due to their direct relationship with the land, they are subject to numerous threats, mainly deriving from human activities and poorly managed catchments. Threats such as increased sediment runoff from clearing land for development and  pollutants like untreated stormwater can result in changes to estuarine habitats and resident plants and animals.

Estuarine restoration involves reversing the negative pressures put on estuaries and increasing the abundances of species that have historically been abundant in an area. The need for research in this area is great as there is no quick fix for all species.

Some examples of research conducted by scientists at NIWA and in collaboration with other government agencies and community groups include: