Spotted Handfish

Brachionichthys hirsutus is a small bottom-dwelling anglerfish rarely exceeding 12 centimetres in length, distinguished by its hand-like pectoral fins, which it uses to "walk" across the seafloor rather than swim. Its skin bears fine spots and hair-like dermal spinules, giving rise to its common name. As a lie-in-wait predator, it forages for small crustaceans and worms and lays demersal egg clusters that it attaches to seagrass blades, sponges, or other substrates, a reproductive strategy that limits dispersal and confines populations to very small home ranges.

The species is endemic to Tasmania, Australia, occurring in shallow marine coastal and estuarine waters, particularly around the Derwent Estuary and adjacent bays. Its habitat spans soft sediment, seagrass, and sponge-dominated seafloor within the marine neritic and coastal zone.

Its decline stems from cumulative pressures on the Derwent Estuary and nearby coastal habitats: urban and industrial development, wastewater and industrial effluent discharge, agricultural runoff, and general pollution have degraded water and sediment quality. The introduced Northern Pacific seastar (Asterias amurensis) preys on the handfish's egg masses, compounding recruitment failure. Habitat alteration from coastal development has further reduced suitable spawning substrate.

Conservation efforts include a captive breeding and research program led by Australian marine science institutions, deployment of artificial spawning habitats to replace lost natural substrate, ongoing population monitoring, and control measures targeting the invasive seastar. The species is legally protected under Australian environmental legislation.

Population numbers remain extremely low, with surveys indicating only a small number of individuals across a fragmented range. Despite active intervention, the population trend remains decreasing, and the species continues to face a high risk of extinction without sustained habitat restoration and threat mitigation.