Freshwater Fish in Hawke's BayKia whakamāramatia ngā ika taketake.

Most of the native freshwater fish species in Hawke’s Bay are migratory, meaning they swim between the sea and freshwater at different parts of their life cycle. Some, like our galaxiid (whitebait) species live and spawn in freshwater and use the sea to raise their young, and the juveniles swim back into our rivers at 6 months of age. Others like eels and mullet live in freshwater and go to sea to breed. Lamprey, one of the rarest fish in Hawke’s Bay, spend most of their life at sea and come to freshwater to breed.

Many of these migratory fish do not swim very far inland, and so abundance and diversity generally decreases the further from the sea. For example, you might find 10 different species of fish in the Maraetōtara River near Te Awanga, whereas a stream in the Kaweka Ranges may only be home to a few longfin eels and koaro, or perhaps none at all.

The key take away – what fish species you’d expect to find in a waterway depends on the type of the waterway, the instream and riparian habitat, and the distance inland

A lost cousin from over the ditch?

These eels are native to Australia, and were first detected in New Zealand in the 1990’s in Taranaki. They’ve since been found all around the North Island, including Hawke’s Bay.

Size and distinguishing features

Female spotted eels can grow up to 1600mm long and up to 14kg, males typically only reach 600mm. As the name suggests, the longfin spotted eels have a longer dorsal fin when viewed side-on than their short finned cousins, which extends further along the body than the anal fin (see pic). They also have a browny black mottled pattern.

Habitat and diet

Not much is known about the habitat preferences or life history of the Australian longfin eel in New Zealand. Australian longfin eels feed on a variety of insects when small, and fish when older.

An excellent climber and forest stream dweller 

Threat status - Not threatened
Climbing ability (fish passage) - Excellent
Spawning period – March – September (peak May – July)

Banded kokopu are one of the five galaxiid species that make up the whitebait population. Like koaro, they are excellent climbers, and can scale large waterfalls. They can also form landlocked populations, using waterbodies such ats Lake Tūitra and the Kaweka Lakes as a larval rearing ground instead of the ocean. Banded kokopu have specific habitat requirements, preferring to live in waterways with overhead tree cover. Laboratory studies conducted on juvenile banded kokopu have shown that they are attracted to the pheromones (odour) of adult fish, meaning they can select what streams to enter as whitebait based on where the adults live.

Habitat and diet

Banded kokopu almost exclusively live in streams with overhead vegetation such as trees and grasses. They are rare or absent from much of the east coast of both islands, south of East Cape, probably due to the extensive deforestation that has occurred in the past. They feed on floating terrestrial animals like beetles, ants, wetas and spiders, as well as drifting aquatic larvae. Fencing off and replanting smaller streams may lead to increase in banded kokopu populations in Hawke’s Bay.

Life history

Banded kokopu are diadromous, meaning they spawn and live their adult lives in freshwater, and the larvae go to sea (or a lake) to grow. Spawning occurs in late autumn and winter in the forest litter beside adult habitat. During the next high flow, the eggs hatch and are swept out to sea. The larvae return three to four months later as whitebait.

Size and distinguishing features

Banded kokopu often grow to 200mm, and have been recorded up to 260mm. As their name suggests, banded kokopu can be distinguished from fish like koaro by the presence of thin pale vertical bands across their sides.

A surprising sight in our inland waterways

Threat status - Not threatened

Climbing ability (fish passage) – Poor

Most people think of flounder as a marine or estuarine species, so they are surprised when see a Patiki dart away from them in a river far from the coast. They’ve been seen as far back as Whanwhana in the mid – upper Ngaruroro, and have even been found 250km inland in the Whanganui River! They are amazing at camouflage and can adapt their skin colour to match the underlying substrate.

Habitat and diet

Patiki occupy a wide variety of habitats, from marine, estuarine, slow flowing muddy streams and rivers to large braided rivers. They feed on benthic insects, snails and small fish.

Size and distinguishing features

Patiki can grow up to 450mm in length, but most commonly reach 200-250mm. They may be confused with a yellow belly flounder, until you flip them over and see their silver-grey underside. Yellow belly flounder are unlikely to swim further inland than the upper estuary.

Life history

The life history of patiki isn’t well known, but they make migrations between the seas and freshwater. It’s thought they go to sea to spawn.

The colourful riffle dweller

Threat status - Declining
Climbing ability (fish passage) – Poor
Spawning Period – August – March

When people see their first male bluegill bully they are amazed that such a colourful native fish exists in our waterways!

Habitat and diet

Bluegill bullies are often found in the swift flowing, broken water of our streams and rivers, a habitat they often share with torrentfish. They have an upturned mouth, which suggests they pick their prey such as mayflay larvae from beneath rocks. We find bluegill bullies in our larger rivers like the Mohaka, Ngaruroro Tūtaekurī and Tukituki, but also in smaller waterways which have fast flowing sections. They have moderate climbing ability so can negotiate small barriers and can be found quite far inland.

Size and distinguishing features

The male bluegill bullies grow larger than the females, and may reach 93mm, but more often between 50 – 60mm. They have a striking metallic blue strip on their pectoral fin, with splotchy dots on their head. Spawning males can also have a colourful rich orange or bronze colour.

Life history

Not much is known about the life history of bluegill bullies. They are known to spawn in spring, and the male will establish a territory where the female will lay eggs. After several weeks, the eggs hatch and the larvae are swept out to sea, and after several months the 20mm long juveniles return to freshwater. They are thought to mature at age one and not live longer than two to three years.

Spawning Period – March – June (peak May – July)
Climbing ability (fish passage) – Can jump small shuts and waterfalls

Native to Europe, Brown trout were introduced in the 1880’s from stock from Tasmania. Along with rainbow trout, they make up a highly valued trout fishery in Hawke’s Bay. With a license from Fish and Game, anglers can enjoy our rivers and lakes chasing these hard fighting sports fish. The upper Mohaka and Ngaruroro Rivers are highly prized for their clear water and large trout, and draw anglers from around the world.

Habitat and diet

Brown trout can be found throughout Hawke’s Bay, from lowland estuaries like the Tukituki to the top of the Ngaruroro and Mohaka Rivers. They’re also present in lakes such as Tūtira. Some ‘sea run’ brown trout spend part of their life in the ocean and will enter rivers during spring chasing whitebait and smelt. They eat a wide range of aquatic insects, snails and crustaceans, taking drifting stream insects. They will also eat mice and frogs when larger.

Size and distinguishing features

Brown trout in Hawke’s Bay commonly grow to 1.5 -2kg, with a trophy trout being over 5kg. Some sea run trout in the Tukituki will be over 6kg! Brown trout are deep brown – olive in colour and have brown black and red spots.

Life history

Brown trout will migrate upstream to headwater streams in autumn or early winter, and spawn in gravelly sections. They spawn in pairs; the female digs a hole in the gravel and the deposits from several hundred to a few thousand eggs which the male then fertilises. The female then buries the eggs and they develop over one to two months. The ‘fry’ emerge from the eggs and stay in the gravels for a time and then come out to form loose shoals around the stream margins. Adults will live to up to ten years.

Threat status – Not threatened
Spawning period – August - March
Climbing ability (fish passage) – Juveniles – moderate, Adults - poor

If you’ve seen bullies darting around a lake or stream, there were probably common bullies. They are the least secretive and most numerous of our bully species. Common bullies are poor climbers and often don’t swim very far inland.

Habitat and diet

Common bullies occupy a variety of habitat types, including small streams, margins of gravelly rivers, and still water such as lakes and wetlands. They can form landlocked populations and have established populations in the Tutira Lakes. They eat a wide variety of stream insects, small fish and snails.

Life history

Common bullies mature at age one and will live for up to four years. Males are territorial and will establish a nest under or on top of a large rock. The female will lay several hundred to a thousand eggs in the nest which the male then defends. The male may breed with several females in the same nest. The eggs hatch after several weeks, and the larvae disperse to the sea and return after three to four months.

Size and distinguishing features

Often grow to 100mm, males grow larger than females. Land locked common bullies are often smaller and may only reach 60mm. When in spawning mode, the males turn black with a prominent orange dorsal stripe.

Threat status – Not threatened
Climbing ability (fish passage) - Poor
Spawning period - December – August (Peak March – June)

Smelt are the 6th species of the whitebait fishery, and are highly valued by Māori for mahinga kai. Fishers line our lower braided rivers like the Tukituki and make ‘trenches’ to channelise water and condense schools of these migrating fish into their nets. If you’ve ever held a smelt in your hands you’d remember their distinctive and strong cucumber scent!

Habitat and diet

Smelt form large roving schools and inhabit our lowland waterways, as well as penetrating quite far inland – smelt can be found in the mid – upper Tukituki catchment stream like the Tukipo. They were also spread to inland lakes by Māori for food, and later by Europeans for trout food. Smelt are present in Lake Opouahi. They eat an array of aquatic and terrestrial insects.

Size and distinguishing features

Smelt often grow to around 120mm, but landlocked lake populations are smaller, with individuals usually around 60mm. They are silvery in colour, and can look like inanga, except for the lack of spots. Their smell usually gives them away when trying to ID them!

Life history

Smelt mature at age one or two, and river populations spawn in the lower reaches of rives in summer and autumn, laying thousands of eggs in sandy spots and then dying. The larvae hatch and go to sea, where they return in spring as transparent whitebait like juveniles.

Hawke’s Bay’s only non- migratory bully 

Threat status – Not threatened
Climbing ability (fish passage) - Juveniles – moderate, adults – poor
Spawning period – August – March

Crans bully are the only non-migratory bully in Hawke’s Bay, meaning their larvae do not go to sea. They are found throughout Hawke’s Bay, but are noticeably absent from the Mohaka catchment, where it is thought volcanic ash laden flows from the Taupo eruption of 186AD wiped out fish species. Since then, migratory fish have re-established, but non-migratory fish like crans bully have not.

Habitat and diet

Crans bullies are mostly found in boulder or cobble bottom streams, as well as braided rivers and weedy spring fed streams. They feed on a variety of stream invertebrates.

Size and distinguishing features

Crans bully often grow to 80mm, though males grow larger than females. When in spawning mode, the males turn black with a prominent orange dorsal stripe

Life history

Crans bullies mature at one year old and will live for up to four years. The males are territorial and will establish a nest under a large rock. The female will lay several hundred to a thousand eggs in the nest which the male then defends. The male may breed with several females in the same nest. The eggs hatch after several weeks, and the larvae remain in freshwater.

Non migratory miniature galaxiids

Dwarf galaxids are one of the few non-migratory fish found in Hawke’s Bay.

Habitat and diet

Dwarf galaxids are found in the shallow margins of larger braided rivers like the Tukituki and Ngaruroro, and in larger gravel or cobble riffles of small tributary streams. Dwarf galaxiids feed on an array of invertebrates that live on the stream bed, such as chironomids, mayfly and caddisfly larvae.

Life history

Dwarf galaxids mature at age two, and although not much is known about their spawning behaviour, are thought to spawn near to adult habitat. Larvae and juveniles will exist in small schools in slower marginal habitats during spring and summer.

Size and distinguishing features

Dwarf galaxids look like a small inanga or koaro. They mostly grow to around 70mm.

A pesky introduction but a tasty treat for wading birds

Climbing ability – Poor

Introduced from Hawaii in the 1930’s, gambusia or Mosquitofish have become widespread in the North Island. Their nickname mosquitofish comes from the mistaken belief that they can control mosquito populations. You might see large numbers of these small darting fish in our slow flowing or wetland waterways. One upside to their presence is that they are believed to be a food source for wading birds such as herons, or the endangered Australasian bittern or Matuku.

Habitat and diet

Gambusia are usually found in slow flowing margins or still wetlands habitats. They are highly tolerant to poor water quality extreme temperature ranges from near freezing to 44°C and very salty water. They eat a wide range of aquatic and terrestrial invertebrates. Gambusia are also known to attack native fish and compete with them for food.

Life history

Males mature at 21mm long and one month old, and females at 28mm and six weeks old. Females give birth to live young, and they breed rapidly and can establish large populations very quickly.

Size and distinguishing features

Females can grow to 60mm, but males only grow to about 30mm. They are a stout little fish, the females drab in colour but the males displaying a diverse array of colours. You can distinguish gambusia from native fish by the irregular way they dart – stop – dart around, as oppose to a continuous swimming motion.

The ‘big cousin’ of the common bully

Threat status – Naturally uncommon
Climbing ability (fish passage) – Poor
Spawning period – August - March

As the name suggests, giant bullies are the largest of the bully species. You probably haven’t ever seen one, but they’re lurking in our slow flowing lowland waterways, close to the coast such as the lower Clive / Karamū.

Habitat and diet

Giant bullies like structure, so they’re often found hiding in undercut banks and in instream debris like logs and large rocks. They’re nocturnal, and emerge at night to feed on small fish, crustaceans, snails and insect larvae.

Size and distinguishing features

Giant bullies often grow over 150mm, and have been recorded up to 240mm. Confusingly, common bullies, can get pretty big too, and to tell them apart you need to count the spikes in the dorsal fin – common bullies have seven or six spikes, whereas giant bullies have six.

Life history

It’s presumed that giant bullies are migratory, but their life history is not well known. Scientists know they spawn in spring, and the female will lay thousands of eggs in a nest under a large rock or log which the male will defend. The eggs hatch after several weeks, and the larvae may go to sea or remain in the estuary.

The large schooling herbivore of our lowland rivers

Threat status – Not threatened
Climbing ability (fish passage) – Poor

Grey mullet are a marine wanderer – meaning they can be found out at sea, in our estuaries or in our lowland waterways near the coast. You may have seen the shiny bellies of these large fish shimmering as they twist algae of stones. They’re valued for mahinga kai, taste great smoked and make great snapper bait!

Habitat and diet

Grey mullet can be found in our estuaries like the Ahuriri and Waitangi, and will venture reasonable distances inland in rivers like the Wairoa, Waikare, Esk, Tukituki, Ngaruroro Tutaekuri and Karamu. They can form large schools, and will graze on plant material and detritus

Size and distinguishing features

Grey mullet can grow surprisingly large, up to 750mm, and 5kg. They look similar to yellow-eye mullet, but are often thicker in body and grow larger.

Life history

Grey mullet span in the marine area, with hundreds of thousands of tiny eggs.

Wild descendants of aquarium ancestors

Climbing ability (fish passage)– Poor
Invasive status - Although exotic, goldfish are not though to compete with native freshwater species or be damaging to our waterways.

Wild goldfish are more common than people think, and are often confused with the more invasive and troublesome Koi carp, which are a noxious pest. If you do come across a large goldfish in one of our waterways, get in touch with us at 06 835 9200 as we can use eDNA testing to make sure it’s not a Koi carp.

A face out of science fiction

Threat status – Nationally vulnerable
Climbing ability (fish passage) – Excellent

Lamprey are perhaps the most unusual freshwater fish in New Zealand, both in terms of their appearance and their life history. They are incredibly secretive, so most New Zealanders would have never seen one. We don’t know much about where Lamprey live in Hawke’s Bay, but they have been caught by whitebaiters and found in Rivers like the Nuhaka, Wairoa, and Tukituki.

Life history

Adult lamprey spend several years at sea as parasites on larger fish and then and migrate upstream in winter and spring. They hide under boulders or undercut banks and wait for 14 to 16 months for their ganads to develop for breeding. In this time they don’t feed at all! They spawn in these habitats, and then die. Lamprey larvae spend around four years buried in fine sediments as filter feeders in freshwater before metamorphosing into miniature adults that then migrate downstream to the ocean.

Size and distinguishing features

Adults grow to 450-750mm. Lamprey look eel like, except for their round, sucker like mouth.

Threat status – Not threatened
Climbing ability (fish passage)– Juveniles – moderate / good, adults poor
Spawning period - August - September

Male redfin bullies compete with bluegill bullies for the best looking native freshwater fish - their splendid red fin and body stripe displays are a sight to behold!

Habitat and diet

Redfin bullies like reasonably swift water and prefer large substrates like gravels and cobbles where they can hide. They can be found in our large braided rivers like the Tukituki and Ngaruroro, as well as our small coastal creeks. They eat an array of stream insects like midges (chironomids), mayflies, caddisflies, small crustaceans and snails.

Size and distinguishing features

Redfin bullies have been recorded to grow to 122mm, but will most often grow to 80mm in size. Both males and females have distinctive diagonal stripes on their cheeks. The males have bright red and orange stripes and fins.

Life history

Redfin bullies spawn in spring, and the male will turn jet black and establish a territory beneath a large rock where the female will lay thousands of eggs. After several weeks, the eggs hatch and the larvae are swept out to sea, and after several months the 20mm long juveniles return to freshwater. They are thought to mature at age one and may live for more than four years.

The cleanwater taniwha

Threat status – Declining
Climbing ability (fish passage)– Excellent

The longfin eel is endemic to New Zealand, which means it is found nowhere else in the world. You might find a longfin in a lowland stream near you, or see one in a small stream all the way back in the Kaweka Ranges! They are impressive climbers when they are young, and are able to climb large waterfalls.

Habitat and diet

Although longfins can be found in a variety of habitats including farm drains, they typically prefer cleaner water and will swim far inland. They are secretive and nocturnal, and much more active in warmer months than in winter. Longfin eels feed on a variety of insects, crustaceans and snails when small, and fish when older. They have been known to feed on small birds such as ducklings!

Size and distinguishing features

Longfin eels are the largest of the world’s freshwater eel species. Female longfin eels can grow up to 2000mm long and up to 40kg, males typically only reach 700mm. As the name suggests, longfin eels have a longer dorsal fin than their shortfinned cousins, which when viewed side on extends further along the body than the anal fin (see picture below). Also, longfin eels when folded have wrinkly skin compared with the tight skinned shortfins.

Life History

Male longfin eels mature at 25 years, and females at 35 years, but females may stay in our waterways as long as 100 years. Scientists have used satellite pop up tags to find out exactly where longfin eels go to spawn, and now think their spawning ground is in the Tonga Trench, near Fiji and New Caledonia. Before they go, they undergo changes to make their journey easier (eyes get bigger, lips become thin and their head becomes pointed). Their larvae returns to NZ over the next 18 months, where they enter our rivers as ‘glass eels’ around 50- 70mm long.

A highly prized sportfish

Climbing ability - Can jump small waterfalls
Spawning period - September – July (peak March – July)

Introduced in the 1880’s from California, rainbow trout make up a highly valued trout fishery in Hawke’s Bay. With a license from Fish and Game, anglers can enjoy our rivers and lakes chasing these hard fighting sports fish. The upper Mohaka and Ngaruroro Rivers are highly prized for their clear water and large trout and draw anglers from around the world!

Habitat and diet

River fish inhabit faster flowing water, waiting for drifting stream insects like stoneflies, mayflies and caddisflies, as well as terrestrial insects like cicadas and spiders.

Size and distinguishing features

Rainbows will most often grow to around 3kg. They have a distinctive pinky – rosy colour to their gills and sides.

Life history

Rainbow trout will migrate from our larger rivers and lakes to spawn in late winter or early spring in small gravely streams. The females dig a small hole with her tail in the gravles, called a ‘redd’, where she deposits her eggs. The males fertilise the eggs with sperm, and then are covered by the female. After a month or two, the eggs develop and young fish will form schools and can be seen darting around river margins.

A resilient taonga species and familiar sight in your local stream

Threat status – Not threatened
Climbing ability (fish passage) – Excellent

The shortfin eel is native to New Zealand, but not endemic (meaning it occurs elsewhere too). Shortfins can be found in Australia, New Caledonia, Norfolk Island, Lord Howe Island, Tahiti, and Fiji. They are a taonga species, treasured by Māori for mahinga kai.

Habitat and diet

Shortfin eels typically inhabit lowland slower flowing streams wetland and lakes but can climb large waterfalls when young. They are secretive and nocturnal, and much more active in warmer months than in winter. They are our least sensitive freshwater fish species to things like water temperature and dissolved oxygen, and will exist in high numbers in productive or degraded waterway systems like drains. Shortfin eels feed on a variety of insects, crustaceans and snails when small, and fish when older (>500mm long).

Size and distinguishing features

Female shortfin eels can grow up to 1200mm long, males typically only reach 600mm. As their name suggests, shortfin eels have a shorter dorsal fin than their longfinned cousins, which finishes about the same point as the anal fin (see pic). Also, shortfin eels have tight skin compared with longfins wrinkly skin.

Life History

Male shortfin eels mature at 15 years, and females at 30 years, but females may stay in our waterways as long as 40 years. They then migrate to somewhere near Samoa to spawn, a journey that can take six to nine months! Before they go, they undergo changes to make their journey easier (eyes get bigger, lips become thin and their head becomes pointed). Their larvae return to NZ over the next 18 months, where they enter our rivers as ‘glass eels’ around 50- 70mm long.

Swift water dwellers and relatives of the Marine Blue Cod!

Threat status – Declining
Climbing ability (fish passage) – Poor
Spawning period - December - June (Peak Jan – May)

Most people would have never seen a torrentfish, as they mostly live in fast broken water feeling on invertebrates (bugs) that live on rocks. Their closest relative are Blue Cod. Torrentfish are bullet shaped and have strong fins to help them live in fast water.

Habitat and diet

As their name suggests, torrentfish prefer fast flowing water, and are most often found in rapids or fast riffles, living amongst large substrates like rocks and gravels. They are especially prevalent in the riffles of our braided rivers like the Tukituki and Ngaruroro, but are also found in small streams, as long is there is fast water present.

Size and distinguishing features

Torrentfish can be surprisingly large for a fish nobody gets to see, reaching up to 200mm. When females are full of eegs, they can look rather obese! They are an unique looking fish compared to other native species, with four diagonal black stripes along their grey body.

Life History

Torrentfish are diadromous, which means they live in freshwater as adults, but their larvae go to sea and return as small juveniles about 20mm long.

Marine wanderer and introduction to fishing for many kiwi kids

Climbing ability (fish passage) – Poor

Yellow-eye mullet are often the fish that kiwi kids catch off the wharf or at the beach. They live in our estuaries and will sometimes travel quite far inland. They’re an important food source for other marine fish and birdlife.

Habitat and diet

Yellow- eye mullet mostly inhabit marine and estuarine areas but will swim up and spend time in low lying stream and rivers such as the Karamu. They eat a variety of small crustaceans, detritus and algae.

Size

Yellow- eye mullet can grow up to 500mm but are mostly less than 300mm.