Activities for Dune Care


Draw a beach profile, showing the different zones of the beach. Be sure to do this at low tide so you can see the structure of the beach as far out as possible. Are there sand banks offshore? Are there sand dunes? Are there plants that can live in the sand? How far inland does the sand go? Are there old sand dunes now covered with forests (or houses) behind the beach? Does a river or creek or a storm drain enter the beach? What effect does this have on the distribution of the sand? How deep is the sand on different parts of the beach?

Determine how beach profiles and particle size differ between beaches exposed to heavy waves and protected beaches.

Are there any structures built on the beach? A rock wall? A pier? A road? How does the structure change the distribution of the sand?

Compare old photographs of the beach with more recent ones. Your local council might have a series of aerial photographs of the beach over time. How has the beach and the area around it changed over the years? Photocopy the photographs and draw an outline of the beach and sand dunes. What changes can you find? Have the sand dunes moved towards the sea or inland? Have there been buildings or roads constructed?

Gradually build up a list of undisturbed beaches, damaged beaches, and beaches that have been improved by local effort. Perhaps your local council already has such a list. If so, obtain a copy and discuss why the different beaches are the way they are.

Visit a beach with high recreational use and nearby housing. Compare what you see there (vegetation, dune structure, erosion, sea creatures, birds) with a visit to a beach where few people go.

When you visit a beach, imagine what it must have looked like before there were any people in New Zealand, perhaps a thousand years ago. Draw a picture of what you think the beach looked like then and another showing what the beach looks like now. If you like, draw a third showing what you think the beach will look like in another thousand years.

Collect some sand from different beaches (have students from other schools exchange samples from their beach) and from different parts of the beach. Keep accurate field notes and label the sand so you know where it came from.

Examine the sand under a microscope or magnifying glass. Can you find differences between the samples? What are they and how do they relate to the origin of the sand and conditions on the beach? Describe the sand grains, giving their size, colour, and if they are made of rock or skeletons of living creatures.

Is your sand made from skeletons of living creatures or from rocks or both? Drop some sand grains into a clear glass or test tube of white vinegar. Are there bubbles of carbon dioxide rising from the sand? Try different colours of sand grains, sorting them carefully under a magnifier. Which ones react with the vinegar? Sand made from rocks is made mostly of silica - just as glass is. Glass does not react with vinegar. Sand made from skeletons is made of calcium carbonate. What happens when vinegar comes in contact with calcium carbonate?

Grow some pingao or spinifex seeds. What conditions do they like best? Work with your local council to replant the seedlings when they are old enough.

Survey the dune plants in your area. Are any of them imported? Are any of them endangered? What is the extent of pingao surviving in your area?

Students research the history of a community beach care group established to improve sand dunes. They present a report evaluating the impact of the group's activities.

Join or organise a beach care group and remove imported plants, especially if they are just getting started in your area. Remember the dunes must be replanted right away once the imported plants are removed.

If you live near the coast, examine your land and garden for aggressive weeds. Remove them and dispose of them properly, perhaps by mulching and composting. Never put garden cuttings on dune areas. Replant with native seeds. Ask your local Forest and Bird protection society for information about appropriate plants for your area.

Can you identify the succession of plants from new to old dunes? Set up a transect to map the vegetation sequence. Map changes in height above sea level, sand particle size, protection from wind, and changes in plant numbers and density.

What problems must these plants solve to be able to survive on sand dunes?

What insects can you find on the beach and the dunes? Many of them leave tiny trails on the sand but only come out at night. Where do they live during the day? Look out for the little Katipo spider. It lives in old cans, driftwood and near the base of dune plants. The female is poisonous and can be dangerous if you pick it up. She is about 6-mm long and has a shiny black body with a bright red patch on the rear of her abdomen.

Sandhoppers look like insects but they are amphipods - related to shrimps. They eat all sorts of dead material - plant and animal - and along with the sea gulls, crabs, sand lice and snails, help rid the beach of dying and dead creatures. Without their help, the beaches would stink of rotting vegetation and dead animals. Try placing a small piece of dead fish or cockle in a tide pool or on a sand flat and quietly observe what happens.

Study the birds that depend on the beach and help protect their nesting areas.

Design and carry out a survey of the local community near a beach. How much do they know about the dunes and beaches? What do they feel about the issues related to dune protection? About exotic plants? Use of the dunes? Community participation in maintaining and protecting dunes?


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