Five Islands Nature Reserve; Mapped Geographic Boundaries and Protected Coastal Island Landscapes

The Five Islands Nature Reserve was established in the mid-twentieth century as part of a broader push to safeguard the biological values of New South Wales' coastal islands. It was formally dedicated as a fauna reserve on 10 June 1960, and is today managed by the NSW National Parks and Wildlife Service. The reserve is recognised for both its biological and Aboriginal heritage significance.

Human use of the islands long predates this formal protection. During the last ice age, around 18,000 years ago, lower sea levels meant the islands were simply part of the mainland coast. By the time Europeans began exploring the area south of Sydney in the late eighteenth century, the mainland opposite the islands was occupied by the Tharawal people. Cattle and rabbits were introduced to the islands before 1861, and in 1867 the Perkins family built a house on Big Island, living there until 1872 while grazing cattle and catching sharks. In the early twentieth century, the seabed west of Big Island was mined for shells, further altering the surrounding environment.

Despite the gazetting of the reserve in 1960, ecological recovery has been an ongoing challenge. Long-running impacts from grazing animals, introduced grasses and soil erosion have shaped the present-day vegetation communities, and management has had to balance the protection of seabird breeding habitat with attempts to restore native plant cover.

The landscape of Five Islands Nature Reserve is one of small, low-lying continental islands set against the open waters of the Tasman Sea. The highest point in the group is Big Island, which reaches only about 16 metres above sea level, while nearby Rocky Islet rises barely a metre above the water. Across the reserve, the islands vary from substantial landmasses of around 17.7 hectares down to rocky outcrops of less than a hectare, creating a diversity of exposure to wind, spray and shore conditions.

Geologically, the islands are composed of volcanic rocks roughly 250 million years old, partly capped by sedimentary layers. Their present shape owes much to the end of the last ice age: as sea levels rose, wind and waves stripped much of the original sand and soil cover, leaving behind rocky remnants with only thin, easily eroded soils. The deepest soils are found on Big Island, but these too have been affected by past grazing, which accelerated natural erosion processes.

Seen from the mainland, the islands form a distinctive skyline along the Illawarra coast, with their dark vegetated slopes and rocky shores standing out against the blue of the Tasman Sea. From a distance, their varied profiles and scattered arrangement give the reserve a layered visual identity, while up close the islands reveal a fragmented but visually rich coastal terrain shaped by wind, salt and time.

Ecologically, Five Islands Nature Reserve occupies a transitional position between marine and terrestrial environments along the Illawarra coast. The shallow soils and exposed conditions support a mix of coastal vegetation communities that include both native plant species and introduced grasses, with vegetation cover varying considerably between the larger island of Big Island and the smaller, more wave-exposed islets.

The most persistent ecological challenge has been the degradation of native plant communities, especially on Big Island. Past grazing by cattle and rabbits, combined with the spread of exotic species such as Kikuyu grass, has suppressed regeneration of indigenous vegetation. Kikuyu in particular competes aggressively with native plants and can interfere with the burrowing habitat needed by petrels and shearwaters, making its control an ongoing concern for reserve management.

Marine influence is central to the ecological identity of the reserve. The islands lie within the productive waters of the Tasman Sea, and intertidal fringes support marine invertebrates such as Waratah anemones and sea dragons, as recorded in early twentieth-century observations. The combination of cool offshore waters, exposed rock platforms and sheltered bays supports a rich variety of coastal marine life that complements the terrestrial ecosystems on the islands themselves.

Wildlife is the defining feature of Five Islands Nature Reserve, with the islands best known for their seabird colonies. Historical records from 1914 describe hundreds of little penguins breeding in burrows alongside shearwaters and gulls, while a 1952 presentation identified little penguins, white-faced storm petrels, wedge-tailed shearwaters (muttonbirds), crested terns and silver gulls as breeding on the islands at that time. Nearby, the mainland coast at Red Point also hosted what was then Australia's only confirmed mainland colony of muttonbirds, though that site suffered from human disturbance.

Today, the reserve continues to support a remarkable variety of breeding seabirds, including the sooty oystercatcher, little penguin, wedge-tailed shearwater, short-tailed shearwater, crested tern, white-faced storm petrel, silver gull, kelp gull and Australian pelican. Ongoing research by the Southern Oceans Seabird Study Association has helped track these populations and inform management of the islands.

Reptiles are also an important part of the fauna, with species such as the eastern water skink, common garden skink, weasel skink and three-toed skink recorded across the reserve. Larger marine animals occasionally appear along the islands' shores, with Australian fur seals, New Zealand fur seals and leopard seals sometimes hauling out on the intertidal fringes. Together, these groups make the islands an unusually rich wildlife refuge for such a small protected area.

Five Islands Nature Reserve is valued in conservation terms primarily as a refuge for breeding seabirds in a section of coast that has been heavily modified by urban, port and industrial development. As an IUCN Category IV habitat and species management area, the reserve's main role is to maintain specific wildlife populations and native vegetation communities rather than to keep a landscape in an untouched wilderness state.

Key conservation concerns include the long-term recovery of native vegetation communities, the control of invasive plants such as Kikuyu grass, and the management of threats to seabird burrowing habitat. The interaction between Kikuyu and burrowing petrels is particularly important, because the grass can disrupt the soft-ground nesting conditions these birds rely on.

Another significant aspect of the reserve's conservation profile is its role in seabird research and monitoring. Its accessibility from the Wollongong and Port Kembla region, combined with its relatively undisturbed breeding sites, has made it a focal point for organisations such as the Southern Oceans Seabird Study Association. This research is central to understanding local seabird populations and to informing conservation decisions on other near-shore islands along the New South Wales coast.

The cultural context of Five Islands Nature Reserve is shaped by its deep association with Aboriginal heritage along the Illawarra coast. When Europeans first visited the area south of Sydney in the late eighteenth century, the mainland opposite the Five Islands was home to the Tharawal people, and the islands themselves are central figures in Tharawal and broader Aboriginal Dreamtime stories.

A well-known Dreamtime narrative describes the West Wind, who lived on the Illawarra Range, and his six daughters. Five of the daughters were cast into the sea on pieces of the mountain for their unruly behaviour, becoming the five islands, while the remaining daughter, Geera, eventually turned to stone and became what is now known as Mount Keira overlooking the coast. This story weaves the islands into the broader cultural landscape of the Illawarra escarpment.

European use of the islands has also left a cultural imprint. Cattle and rabbits were present before 1861, and the Perkins family lived on Big Island from 1867 to 1872, grazing cattle and catching sharks. Mining of the surrounding seabed for shells in the early twentieth century further marked the islands as a working part of the coastal economy before their formal protection in 1960.

A small but biologically dense reserve, Five Islands Nature Reserve concentrates a remarkable amount of wildlife value into a group of low continental islands close to one of Australia's major industrial port cities. Its combination of breeding seabirds, reptile populations and occasional marine mammal visits makes it disproportionately important for conservation on the Illawarra coast. The reserve's strong ties to Aboriginal Dreamtime narrative give it a distinctive cultural dimension that complements its ecological role.

The most suitable times to experience Five Islands Nature Reserve tend to align with the milder months along the New South Wales south coast, when cooler temperatures and calmer sea conditions generally make offshore areas more accessible and when seabird breeding activity on the islands is well established. Spring and early summer bring active breeding colonies of penguins, shearwaters and storm petrels, which is a key feature of the reserve.

Winter and early spring can be quieter in terms of breeding spectacle but offer their own character, with cooler weather, reduced crowds in the wider region and the chance to observe less disturbed wildlife. Visitors interested in seabird research will find it useful to time a visit around known periods of monitoring activity by organisations such as the Southern Oceans Seabird Study Association, though access to the islands themselves is generally restricted and managed to protect wildlife.