Mystery fish washed up on Horseshoe Bay at Bermagui have tentatively been identified as frostfish or Lepidopus caudatus.
One witness reported seeing about seven of the fish on Tuesday, July 11, while a customer at the Bermagui Bait and Tackle shop later claimed to have seen “dozens” of the dead fish on the beach.
A photograph of one of the fish posted on the Narooma News Facebook page generated a lot of debate as to the species of fish with suggestions including hairtail, ribbon fish, barracouta and even long tom.
Check out the Facebook post to see all the comments:
But a check with the Ichthyology department at the Australian Museum Research Institute seems to indicate that the fish are indeed frostfish. The small forked tail or caudal fin was the dead give away.
Also in the trichiurid family of fishes are hairtails, scabbardfishes and cutlassfishes, but the frostfish is the one with the small caudal tail.
“The fish has certainly garnered a lot of debate,” said ichthyologist Amanda Hay. “You are correct. It is a frostfish, the caudal fin is the give away.”
The Australian Museum included the following links:
While the identity of the fish may have been solved, where they came from remains a mystery.
Local commercial fisherman Jason Moyce, also known as Trapman Bermagui, indicated the fish in the photograph may have been one of several that fell off a trawler as it was unloaded in Bermagui Harbour. He also wrote that he thought it was a ribbonfish.
But Bermagui Fishermen’s Co-op chairman Rocky Lagana said while trawlers regularly landed frostfish or ribbonfish, they had their heads removed upon landing, so all the fish falling off the back of a trawler was unlikely.
He said these fish did migrate north as temperatures cooled and they could have been some kind of natural mortality event.
Frostfish are also caught recreationally by those targeting more sought-after species such as blue-eye cod in waters of 400 metres deep and deeper.