between species. Distribution and habitat The Barrier Reef anemonefish is found in lagoons and outer reefs in the Great Barrier Reef, Coral Sea, northern New South Wales, New Caledonia, the Loyalty Islands and Tonga. A. akindynos has been thought to be limited to depths of less than 25 m, however surveys using autonomous underwater vehicles of mesophotic reefs at Viper Reef and Hydrographers Passage in the central Great Barrier Reef observed A. akindynos at depths between 50 and 65 m. Host anemones The relationship between anemonefish and their host sea anemones is not random and instead is highly nested in structure. A. akindynos is a generalist, being hosted by the following 6 out of the 10 host anemones: Entacmaea quadricolor Bubble-tip anemone Heteractis aurora beaded sea anemone Heteractis crispa Sebae anemone Heteractis magnifica magnificent sea anemone Stichodactyla haddoni Stichodactyla mertensii Mertens' carpet sea anemone Reproduction The Barrier Reef anemonefish is a nesting fish. A few days before mating, aggression from the dominant male towards the female increases, and at the same time he begins clearing a nest site, usually on a rock close to the host anemone. The rock is cleaned of algae, sometimes with the assistance of the female. When spawning takes place the female zig-zags over the nest site and the male follows fertilizing the eggs which have been deposited. Between 100 and 1000 elliptical eggs of between 3 and 4 mm in length may be laid. They are attached to the nest site by a mass of short filaments. The male guards and aerates the eggs for 6 to 7 days until they hatch. The larvae are then dispersed by currents and swimming. Larvae mortality is high, with most of the surviving larvae settling on the original reef. Diet The diet of the Barrier Reef anemonefish consists primarily of algae (seaweeds) and zooplankton. The dominant pair in the social hierarchy tend to travel farther from the host anemone in order to find food. The host anemone may benefit from small pieces of food which the anemonefish drop when feeding. Conservation status Anemonefish and their host anemones are found on coral reefs and face similar environmental issues. Like corals, anemone's contain intracellular endosymbionts, zooxanthellae, and can suffer from bleaching due to triggers such as increased water temperature or acidification. The other threat to anemonefish is collection for the marine aquarium trade. The Great Barrier Reef Marine Park Authority