Species Focus - The Giant Boarfish
The Giant Boarfish is a prized target for spearfishermen when they come into shallower depths during summer.
The giant boarfish is the largest of five species of boarfish found in New Zealand’s waters, and also found in southern and eastern Australia. They are not seen that often by divers due to living mostly deeper than recreational diving limits, over the continental shelf down to approximately 200 metres.
However, individuals or pairs sometimes come into shallower water on reef margins, as shallow as five metres, where they often remain for several weeks. The occasional aggregation of several is not unheard of, whilst juveniles tend to congregate more reliably in small loose schools.
An attractive, if somewhat peculiar-looking fish, with broad tiger-like bands along the flanks, alternating silver with olive green-brown. Sometimes individuals are seen with a dense covering of yellow spots upon the normal olive green body, and these are presumed to be males. The reference to pigs (boarfish, sowfish) is due to the elongated snout, which becomes more elongated with age. Juveniles are deeper bodied with shorter snouts, and with more definitive banding. Giant boarfish use their elongated snouts and fleshy lips to snuffle around in the sand and mud for interstitial invertebrates, such as crabs, molluscs and worms; again, similar to terrestrial pigs. They may even blow sand away with jets of water to reveal hidden prey.
A species with some commercial value, more so on the Australian side of the Tasman, giant boarfish are caught in trawl nets on the continental slope. In New Zealand, they are often a non-target species, and even prohibited from sale in some fisheries zones, namely the Auckland/Kermadec regions. They are still caught however as by-catch, when trawling for John Dory and other species that share similar habitat. They are also a prized target for spear fishermen when they come into shallower depths during summer.
The Giant Boarfish - 8 key points
- One of five species of boarfish found in New Zealand.
- Pentaceridae means ‘five horns’, referring to the prominent, sharp spines in their dorsal fins (though not always five in all species).
- The largest boarfish species grow to a length of one metre.
- Other common names include sowfish, duckfish, giant armourhead and giant penfish.
- Adult males are distinctly covered in yellow spots.
- Use their elongated snouts to probe for invertebrate prey.
- Normally found deeper than recreational diving depths, but occasionally seen shallower.
- Spawning aggregations of up to 100 individuals have been seen during summer.