The Mackerel Islands are a gazetted nature reserve. The ever-changing nature of the shore reveals shells and rock formations during a walk along the beautiful natural beaches. A colourful variety of sea life is to be discovered in these tropical waters and the islands are home to many bird species.

Sea Turtles

Sea turtles nest on Thevenard Island between December and March and you can observe the females digging in the sand dunes to lay their eggs and later, the baby hatchlings scurrying to the water’s edge, during these months. Flatback, hawksbill, loggerhead and green turtles abound at the Mackerel Islands’ renowned “turtle highway”.


Several species of dolphins inhabit the waters surrounding the Mackerel Islands including the bottlenose, spinner, striped, common and humpback dolphins. It is rare to have a day out on the water without seeing dolphins close up and friendly.


Whales that have been observed in the area include the pilot whale, false killer whale, sei whale, bryde’s whale and humpback whales. Humpbacks migrate south from June to October, with calving taking place in August. It is common for visitors to the islands to have continuous whale sightings.

Dugongs (Sea Cows)

Dugongs are also found in waters around the islands and can be observed feeding and calving in waters less than 5 metres deep. Dugong breeding occurs between September and April. Sightings are often reported by people using small boats in the shallow waters within 1km of the islands.


24 species of land birds have been recorded on Thevenard Island. In addition, there are up to 31 species of migratory birds occurring in the Mackerel Islands area, including kestrels, quails, godwits, plovers, sandpipers and harriers. Some birds migrate from remote northern hemisphere locations as far as Siberia, and are protected by international treaties. Seabirds, such as terns and shearwaters, nest from October to January.

Mammals & Reptiles

The only native land mammal on the island is the forrest mouse. The domestic mouse also inhabits the island and is most likely to have been introduced. A total of 9 reptile species have been recorded on the island including goannas, dragons, skinks, geckos and our friendly little ta-ta lizards. No snakes or rare or endangered reptiles have been recorded.

Eco Walk Trail

For the energetic and adventurous, the Thevenard Islands Eco Walk Trail is for you. It takes you trekking the circumference of the island with 12 stops of interest, allowing you to absorb its inherent beauty. The walk takes about 3-4 hours and a level of fitness is recommended.

Our Commitment to Sustainable Ecotourism Development

Mackerel Islands has had state-of-the-art facilities installed to support sustainable ecotourism in recent years, including a solar farm and desalination plant. The reverse osmosis desalination plant produces up to 70,000L of crystal clear water per day and runs entirely from the power of the sun.

The solar farm was one of the first using this technology at this scale, comprising:

  • 1200 solar panels delivering 325 KVA of power
  • 650 KW hours of Lithium Ion battery storage
  • 4 x 110 KVA generator backups

The Mackerel Islands remains steadfast in its commitment to future sustainable solutions while developing tourism in the region.