Caring for Northland's dunes

Why protect our sand dunes?

Protect the dunes and they'll protect us

Beaches and sand dunes are the narrow but precious bands of sand that lie between the land and the sea.

Sand dunes are natural habitats for many native species and, in their natural state, they protect land and property from erosion, storms, cyclones and tsunamis.

Large areas of Northland’s coastal dunes have been modified for residential development, roads, recreation farmland and forestry. This has led to extensive loss of native vegetation, increased weeds and dune erosion.

Our dunes are also under pressure from increased beach use. Wheels, feet and animals damage dune vegetation which can lead to significant wind erosion and reduce the ability of dunes to repair after storms.

The good news is that we can all play a part in caring for and protecting Northland’s valuable dunes.

How do sand dunes work?

Sand dunes are always changing as they erode and build-up in cycles. Dune plants play an important role in this process.

Settled weather

Sand builds up on the beach and dunes.

Diagram of dunes and tide above picture of beach during settle weather. 

Storm erosion

Waves erode the beach and dune, eroded sand forms an offshore bar.

Diagram of dunes and tide after storm erosion over a picture of sand dunes with storm erosion.

Post-storm beach recovery

Sand moves onshore and rebuilds the beach. Dune plants grow seaward down the eroded dune face.

Diagram of dunes and tide during recovery over a picture of dunes during post storm beach recover.y. 

Post-storm dune recovery

Dune plants trap sand, gradually rebuilding the dune.

Diagram of dunes and tide showing post storm dune recovery over a picture of sand dunes during post storm dune recovery. 

Thanks to the Dune Restoration Trust of New Zealand for allowing us to reproduce some of its information. www.dunestrust.org.nz 

Sand dune vegetation

Native plant species in our dunes

Images of native dune plants.

Native dune plants...

… can

  • Reduce wind erosion.
  • Build up sand dunes which reduce wave erosion.
  • Speed recovery of dunes after storms.
  • Grow in the hostile coastal environment.  

… can't

  • Prevent direct wave erosion.
  • Withstand excessive damage from people, stock or vehicles.
  • Cope with mowing.
  • Tolerate introduction of unsuitable exotic plants.

Pest plants in our dunes

In many coastal areas, introduced species have been planted to stabilise or beautify dunes. Plants also spread onto dunes from neighbouring properties. 

Unfortunately, these plants aren’t as effective at dune protection as native plants, and they can sometimes make erosion worse. Many introduced species have also become a problem as they can over-run large areas and threaten native species.

Some of the problem species are agapanthus, exotic iceplant, purple groundsel, prickly pear, daisies, boneseed, coastal banksia, freesias, kikuyu grass and wattle.

Exotic ice plant with pink flower.Exotic iceplant.Purple groundsel plant flowering on the sand dune.Purple groundsel.

Help stop the spread of pest plants

Many pest plants are garden escapees – you can help by:

  • Composting garden waste instead of dumping it onto the dunes
  • Removing invasive introduced plants and replacing them with natives.

Contact the Northland Regional Council for removal techniques and suitable replacement plants.

Find our guidelines for weed control on sand dunes

Dune restoration

Restoring and protecting our coastal dunes can help re-establish natural dune form and function, provide a buffer from erosion and storms and provide habitat for native creatures.

Weed and pest control is a vital part of dune restoration projects. Alongside management of beach access this can be enough to allow the dune to repair.

At some sites replanting with native plants is needed to restore natural function and biodiversity values. Where the dune has been highly modified it can be necessary to mechanically reshape the dune and remove exotic vegetation and fill before planting. Keep in mind that some dunes are naturally unstable and are valued environments just as they are. 

Before you start a project to stabilise or restore the dunes, please contact Northland Regional Council for advice. Funding is available for suitable projects.

People removing weeds from sand dunes.Northland CoastCare groups carry out dune restoration projects to protect and enhance native vegetation through pest and weed control, fencing and replanting where necessary.

We can all help protect our beaches

Keep off the dunes
Wheels, feet and hooves can destroy important plants, threaten wildlife and cause dune damage. Follow marked tracks to the beach and only drive or ride on the hard sand.

Watch your dog
Dogs can disturb or kill shorebirds and other wildlife. Don’t let your dog run over dunes or chase shorebirds and keep it away from any fenced off areas.

Leave our beaches litter free
Rubbish can be harmful to people and wildlife on the beach and in the ocean. Please take your litter home with you.

Bin or bury fish carcasses 
Fish heads and bones from fishing are litter and should be taken home and binned, buried or composted.

Leave sand on the beach 
It is illegal to remove sand, pebbles or rocks from our beaches. These materials are the building blocks of our coastline and take years to build up.

Take action – get involved

If you’re keen to get involved in dune restoration work please contact the CoastCare Co-ordinator at the Northland Regional Council.

Phone 0800 002 004 or
email  [email protected]

Pingao and Spinifex growing on sand dunes.Pingao (foreground) and spinifex are able to tolerate the harsh front dune environment and are important sand-binding plants.