Eye-stripe surgeonfish

In its native range this colourful, quintessentially tropical species inhabits coral reefs and is also known as Dussumier's surgeonfish, Hawaiian surgeonfish, ornate surgeonfish, and palani.

This species of surgeonfish is found in both the Indian and Pacific oceans, from Africa in the west to Hawaii in the east. The most northern populations occur in Japan and the southern edge of their range is New South Wales in Australia.

Within their native range eye-stripe surgeonfish occur from shallow coral reef crests to deep reef slopes (from 4m to 131m), where they can often be seen grazing on the algal films and diatoms that grow on the reefs they inhabit. In New Zealand, eye-stripe surgeon fish have been found from North Cape down to White Island and are often seen schooling with juvenile parore and snapper.

So how do you know if the tropical fish you spotted during your dive or fishing trip was an eye-stripe surgeonfish? Firstly, all species in the family Acanthuridae have sharp ‘blade-like’ spines on their caudal peduncle (the narrow part between the fish's body and the tail fin), hence the common name 'surgeonfish'.

Eye-stripe surgeonfish are generally a yellowish-brown colour, and as the name suggests, mature fish have a bright orange band running across their eye. Juveniles of the species tend to lack the distinctive eye-stripe, but they do have a bright blue stripe along the edge of their anal fin and a yellow band on the caudal peduncle at the base of the tail fin.

All of the eye-stripe surgeonfish recorded in New Zealand have been juveniles ranging in length from 2.5cm to 10cm. Juvenile eye-stripe surgeonfish are often very shy and flighty, but will usually stay within a small home range. These juveniles currently don’t survive our winters, which means eye-stripe surgeonfish are not breeding in New Zealand waters.

Within their native range most eye-stripe surgeonfish encountered are around 35cm, but they can grow to a maximum size of 54cm. They will live for up to 30 years and reach reproductive maturity, or breeding size, at around 20cm in length.

So where are the eye-stripe surgeonfish we are seeing in New Zealand coming from? The most likely source populations for juvenile Eye-stripe surgeonfish are Lord Howe Island, Norfolk Island and southern parts of eastern Australia.

Eye-stripe surgeonfish larvae drift on ocean currents for 50 to 85 days, which is a relatively long time in the fish world and more than long enough for them to cross large areas of open ocean to New Zealand.

It is likely that we will continue to see pulses of juvenile eye-stripe surgeonfish arriving in New Zealand waters, facilitated by prevailing ocean currents and storm events. If ocean temperatures continue to increase in New Zealand, we may also see these juveniles start to overwinter and reach breeding size.

If eye-stripe surgeonfish do establish populations here, they may compete with native species like parore and moki for food, so it’s important for us to keep an eye out for this species. If you think you have spotted an eye-stripe or any other surgeonfish in New Zealand waters, send a photograph to WhatsThatFishNZ or a fish taxonomist to confirm the identity. We are particularly interested in photos of larger specimens!