Skip to main content

Our Coast

Our Coast

Our western boundary is almost nine kilometres of beaches. These clean, sandy beaches attract thousands of tourists all year round.

Due to the natural processes of wind and waves, our coastal environment is highly dynamic, naturally erosive, and ever-changing. Our coastline is actively managed to counter the impacts that threaten to damage it.

Wildlife

One of the most cherished parts of living near the beach is sharing it with native wildlife. While we can happily co-exist, sometimes we need some tips for sharing our beaches.

Hooded plovers live on our Southern beaches year-round, but their breeding season is August to March, meaning they nest on the beach during the busiest time of year – spring and summer. They nest at the base of the dunes, on the dry sand, in a shallow nest scrape (a little dent in the sand).

When the chicks hatch, they’re only the size of a 50c coin or about 3cm tall.

They need to source their own food from the water’s edge, which can be dangerous, especially if dogs are unleashed.

It takes around five weeks for a chick to reach the fledgling stage, which means they can fly.

If you see a Hooded Plover on the beach, the best thing to do is to keep your distance.

Green Adelaide has other tips for beachgoers on how to play their part in protecting the beach-nesting birds, which are considered an endangered species.

  • Keep your dog on a leash at the beach – especially during spring and summer.
  • Only walk below the high tide mark during the nesting season.
  • Look for signs and fences indicating a nest or chicks on the beach.
  • Move away quietly when you see a Hooded Plover.
  • Spread the word about the beach-nesting birds.

There are reportedly less than 70 Hooded Plovers across Adelaide and the Fleurieu Peninsula, and it is estimated that there are only 500 to 800 Hooded Plovers in the whole state.

Did you know that off the coast of Kingston Park, Seacliff, and Brighton, there is a unique population of stingrays that are nearly all large, mature females?

What makes this cluster of stingrays unique is that they are present in our waters all year round.

Similar clusters of female stingrays can be found in other parts of southern Australia but are seasonal in nature.

Within our local population, there are two main species of stingrays:

  • Southern eagle rays have a mottled appearance with pointy fin tips, a small fin on the tail and a blunt snout
  • Smooth rays are plain grey with an irregular pattern of small white spots, rounded fins and a pointy snout

Both species carry a barb on their tails, which can be used in self-defence to deliver a lethal injection of venom. While these animals are not aggressive, they may attack in self-defence if provoked.

These stingrays enjoy coming close to the shore. This is likely because there is easy access to food, shelter and warm water, which helps with their metabolism and provides a safe haven for eagle rays to give birth to live offspring, potentially several at a time.

Please do not feed or touch the stingrays to ensure their safety and yours. Beachgoers are encouraged just to enjoy the pleasure of watching them glide by, perhaps take some photos and let them go on their way.

Stingrays have a large hole behind each eye. This is called a spiracle, which allows them to draw in oxygenated water from above their body to breathe even when lying flat on the sea floor. They also use the spiracles to pump water into the sand to hunt for prey.

Their flat shape means that they are specialists in feeding on the sea floor, targeting prey such as crabs, squid and fish.

In marine ecosystems, they play an important role as mesopredators (middle predators), which means they help to control prey populations and provide large predators, such as sharks, with food.

The smooth ray is the largest ray in Australia. It can grow to 4.3 metres in length, 2 metres wide and weigh up to 350kg.

Beach Management

Council and the State Government share responsibility for managing our beaches as part of the Adelaide Living Beaches strategy implemented by the Department of Environment and Water.

Sand naturally moves northwards along Adelaide's coastline. Before European settlement, the beaches were naturally replenished from the dunes, so sand movement could continue almost indefinitely.

However, development along our coast has resulted in large quantities of sand either being 'locked up' or removed from the beach system, preventing natural replenishment. As a result, natural processes have eroded the beaches, and without artificial replenishment, sand will continue to erode away.

To counteract this, sand is pumped from Glenelg every winter, where it naturally builds up, and deposited at 11 key locations between Kingston Park and Glenelg. This activity will need to continue every year to maintain our sandy beaches.

Coastal Adaptation Planning

Coasts are dynamic, constantly changing environments impacted by both development and storms that are increasing in severity and frequency due to climate change and sea level rise.

In some locations, these impacts are occurring at a fast rate and damaging important community assets or infrastructure. To understand and plan for the risks and impacts associated with sea level rise, the City of Holdfast Bay is working through a complex multi-year coastal adaptation planning process with a range of stakeholders to develop a Coastal Adaptation Plan for the future of our coast.

Sand Dunes

A healthy dune system has many important benefits, from protecting against storm erosion to providing habitats for birds, reptiles, and insects and providing sand for the beaches.

Before extensive coastal development in the 19th and 20th centuries, the original dunes were up to 20 m high and extended 200 - 300 metres inland. They were an important source of food and shelter for the traditional owners, the Kaurna people.

We use sand-drift fencing to help recreate and protect dune systems from erosion. This fencing traps wind-blown sand in the vicinity of the fence where natural vegetation is not sufficient. However, such fencing does not completely prevent natural erosion.

We have three main dune areas behind our beaches: the Brighton to Seacliff dunes, the Glenelg dunes, and the rare remnant Minda Dunes at Somerton Park.

Since the late 1990s, we have conducted revegetation and restoration projects with the help of local residents, schools, and volunteer conservation groups.

The Minda dunes are important remnant ones, one of only two original dune systems along the Adelaide coastline. During 2018-19, the council, in partnership with the State Government and Minda Inc., undertook significant biodiversity works to improve the Minda dunes.

We have developed a Holdfast Bay Dune Biodiversity Action Plan, which captures important information about the current state of our dunes and makes prioritised recommendations to improve biodiversity.

Coastal Vegetation

Our coastal plant communities feature diverse plant species and life forms, such as ground covers, grasses, small to large shrubs, wildflowers and climbers. Most of these are highly adapted to survive in the harsh coastal environment, particularly tolerant to salt, wind and hot, dry conditions.

These areas of native coastal vegetation form important habitats for wildlife. They play an important role in stabilising the dunes and forming a protective buffer between land and sea.

We strongly encourage the use of local native plants in creating coastal water-wise gardens because they:

  • are perfectly suited to our soil and climate
  • thrive without additional water
  • don't require fertilizers or pesticides
  • provide a natural habitat for indigenous birds, insects, and reptiles.

Our Green Living program subsidises residents to purchase local native plants. See our Green Living Gardens section for information about our subsidy and environmentally-friendly gardening.

Coastal Weeds

A weed is any plant that grows where it is not wanted. Unfortunately, introduced species form a significant proportion of our coastal vegetation and include not only plants that have been introduced from overseas, such as Gazania but also native species from other regions of Australia, such as the coastal tea tree, which comes from NSW.

Weeds affect native plants by successfully overpowering and replacing them and, in some cases, by forming conditions that prevent indigenous species from establishing around them.

Reducing the damage caused by weeds and protecting our coastal environment and its biodiversity is a key priority for us. Our specialist teams actively control unwanted plants throughout our reserves and foreshore regions.