Land-based Effects on Fisheries and Ecosystems

Runoff from the land can have huge effects on our coastal ecosystems and the fisheries they support.

Streams and rivers carry sediments, nutrients and bacteria from our roads, farms and forests into the sea; while stormwater running down the drains from our streets and driveways pollutes estuaries and harbours with a cocktail of oil and other chemicals.

In many cases the effects of these are not instantly obvious and build up over many years. Occasionally, effects reach a point where we start to notice them – often when a fishery we care about is affected.

If no changes are made to the way we manage and use the land, sediment and other runoff could have ever-increasing impacts on both marine and freshwater ecosystems. This may cause many fish and shellfish populations to decline.

Everyone needs to be involved in addressing land-based effects, because we are all a part of the problem and all part of its solution.

The government’s goal is to see the health of affected ecosystems and fisheries restored. Some of the communities and groups working together to address land-based effects are already reporting positive results. For example, in Whaingaroa (Raglan) Harbour, water quality is now improved through a local initiative to fence and plant waterways leading into the harbour.

Similarly, in Golden Bay, farm runoff has been reduced through a local initiative involving local dairy and marine farmers, Fonterra, and Tasman District Council.

Many different groups have a stake in New Zealand's coastal and marine environment, and responsibilities for its management are shared among a range of central and local government agencies.