The Dusky Morwong is the largest species in this family (Cheliodactylidae) growing to a maximum size of 1.2 metres. Juveniles are deeper bodied than the elongate adults and possess many orange-brown spots on a silvery green base which fade as the fish matures. The Dusky Morwong chooses a diet of consisting of algae, which for its large size lacks the nutrition required for an active lifestyle, so they are often seen resting amongst seagrass. They are often speared because of these slow moving habits, their abundance and their size, however their flesh is considered poor eating quality compared to that of other morwongs.
They are endemic to the cool southern waters of Australia where they inhabit seagrass and sandy patches in shallow coastal estuaries and bays and inshore reefs from New South Wales to Lancelin, WA.
Other common names include Strongfish, Black Butterfish, Butter Perch, Butterfish, Nunckla, Nunda, and Tillywurti.
Occurrence at the Busselton Jetty
The Dusky Morwong is one of the larger and most common residential fish underneath the jetty. Juveniles are often perched on the ledges around the observatory where they may stay for hours. People often confuse this lazy behaviour with the fish being sick or dying. Ten metres from the observatory, near the fallen piles, is where the larger, full size Dusky Morwongs sit suspended in the water column.
Image by: O. Rynvis