Gilbert P. Whitley’s classic ‘Marine Fishes’ pocket guide published in 1962 describes garfish as an “exquisite table fish, in spite of their many fine bones. They swim slowly at the surface feeding on minute organisms.” But Hall and MacDonald (1986) Victorian Dept of Conservation Forests & Land Fisheries Division say “Southern sea garfish are largely herbivorous, seagrasses of the genus Zostera being major component of their diet. Other items recorded from stomach contents include filamentous green algae, diatoms, insect larvae and polychaete worms” Just goes to show, we never stop learning.
Apart from their long and toothless lower jaw, southern garfish (Hyporhamphus melanochir) are also notable for being one of the few Australian fishes that include seagrass as a major part of their diet. Perhaps this is why they generally hang out in depths less than 4 metres?
As you’ll see in Greg Wallis’ fantastic youtube clip of garfish grazing off Brighton, they’re also great at ballet! http://www.youtube.com/watch?v=VC2IYq4x6FU