Story: Coastal fish
Page 2 – Shallow-water fish
Many New Zealand fish live near the shore, in depths of less than 10 metres. They can be divided into two groups: demersals (living on or near the sea floor), and pelagics (living in the water column above).
Most of the fish species found only in New Zealand (endemic) live in the rocky intertidal zone. Of the 83 species found in here, 54 are endemic and few of the remainder are found further afield than Australia.
Demersals: sea-floor species
These small fish, which have three dorsal fins, are Tripterygiidae, the most diverse family of coastal fish in New Zealand – there are over 25 species, mostly endemic. Many are little researched as they are small and hide in rock pools.
The remarkable seahorse (Hippocampus abdominalis) is widespread around New Zealand. It prefers sheltered harbours, estuaries and other coastal waters, where it hunts tiny crustaceans.
The male has a pouch where the female lays its eggs, to be fertilised by the male. The male incubates the eggs, and a month later tiny seahorses are born.
Wrasse are a very large family of tropical and temperate sea reef fish. There are many species in New Zealand waters, the most common being the endemic spotty (Notolabrus celidotus). Also known as kelpie, guffy and paketi, this is a favourite catch for children fishing from the wharf.
Wrasse are mainly loners that swim around rocky areas, eating almost anything that lurks on the bottom or on the rocks. They have flexible bodies and thick lips, and use sharp teeth to pick small creatures off the rocks.
Although 11 species of right-eyed flounder have been recorded in New Zealand, the most commonly seen and caught are sole (Peltorhamphus novaezeelandiae) and sand flounder (Rhombosolea plebeia).
As larvae, flounder have one eye on each side of their heads. Then as they transform into juveniles the left eye migrates to the right side of the head. The left side of the body becomes the underside of this flattened fish, which rests on the sea floor. (There are also left-eyed species.)
Flounder and sole are widespread in muddy and sandy sea floors around New Zealand, well camouflaged by their colour and flattened profile.
Pelagics: open-water species
The yellow-eyed mullet (Aldrichetta forsteri) is common in estuaries, harbours and sheltered bays, and is also found in the lower reaches of rivers. It is known to Māori as aua. In summer, large schools are seen in estuaries. They are often incorrectly called sprats or herrings.
The grey mullet (Mugil cephalus) is widespread throughout the world. In New Zealand it is most common in northern harbours, and is often caught with set nets.
This long, slender fish (Hyporhamphus ihi) looks like a spear. Also known as a garfish, it occurs in shallow coastal waters and feeds on seagrass fragments, shrimps and crab larvae. In turn it is preyed on by kahawai, kingfish and, as it is often near the surface, gannets and shags.