UNDERWATER LIFE of the HAURAKI GULF Species Found in the Hauraki Gulf Marine Park
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This poster celebrates the diversity of marine UNDERWATER LIFE OF THE HAURAKI GULF species found in the Hauraki Gulf Marine Park. Orca Orcinus orca Maki Bottlenose dolphin Tursiops truncatus Terehu 5.5-9.8m 1.9-3.9m Common dolphin Delphinus delphis Aihe Flying fish 1.7-2.7m Australasian gannet Fluttering shearwater Cheilopogon pinnatibarbatus Morus serrator Takapu Puffinus gaviaPataka 25-45cm 89cm 33cm Bryde’s whale Balaenoptera edeni 11.5-14.5m Blue shark Prionace glauca Mango-pounamu Pilot whale New Zealand fur seal Arctocephalus forsteri Kekeno up to ≈ 4.3m Globicephalus macrorhynchus Upokohue 3.8-6m male: 2.5m | female: 1.5m Hammerhead shark Sunfish Sphyrna zygaena Mango-opare Mola mola up to ≈ 3.5m 80-150cm Skipjack tuna Blue maomao Katsuwonus pelamis Aku Scorpis violaceus Maomao Pilchard 45-100cm 20-40cm Manta ray Sardinops neopilchardus Mohimohi Manta birostris 10-25cm Snapper Pagrus auratus Tamure 30-80cm Trevally Pseudocaranx georgianus Araara Red moki John Dory Kingfish 30-60cm Cheilodactylus spectabilis Nanua Zeus faber Kuparu Seriola lalandi Haku 40-60cm 100-200cm 30-40cm Kahawai (female) Arripis trutta Eagle ray Bluenose Hapuku 40-60cm (male) Myliobatis tenuicaudatus Whai repo Hyperoglyphe antarctica Matiri Polyprion oxygeneios Sandager’s wrasse 60cm-1.5m (across wings) 60-140cm 60-200cm Coris sandeyeri 20-45cm 5 6 7 1 2 8 Crayfish or rock lobster 3 Jasus edwardsii Koura Common kelp 4 Kina PROTOCTISTA: Ecklonia radiata Evechinus chloroticus Foraminifera 9 10 Globorotalia inflata ZOOPLANKTON: 1. Copepod Calanus australis 2. Ctenophore (comb jelly) Pleurobranchia pileus PHYTOPLANKTON: 5. Diatom Chaetoceros decipiens 6. Dinoflagellate Gymnodinium simplex 3. Salp Thalia democratica 4. Euphausiid (krill) Nyctiphanes australis 7. Coccolithophore Emiliania huxleyi 8. Dinoflagellate Ceratium fusus 9. Diatom Pseudo-nitzschia australis 10. Diatom Guinardia delicatula WILDLIFE OF THE HAURAKI GULF MARINE PARK The Hauraki Gulf Marine Park was established in 2000 under the Hauraki Gulf Marine Park Act. As our first national park of the sea, made up of 1.2 million hectares of water MARINE BOUNTY and more than 30 major island groups, it protects scenery, ecosystems and natural features that are nationally significant for their beauty, uniqueness and scientific value. Diver and snapper. It is estimated fishing has depleted snapper Photo © Tony and Jenny Enderby Photo © Tony and Jenny Enderby populations by more than 80% in the Hauraki Gulf. Densities of harvestable size snapper are around 14 times higher in marine Safe havens reserves than surrounding fished areas. Within the Gulf there are currently five small marine reserves which protect less than 0.3 per cent of the Gulf’s marine area. As well as Marine reserves in the Gulf being small, these areas are not representative of the Gulf’s range of habitats and species with, for example, only an estimated 37 per cent Boundary of Hauraki Gulf Marine Park of intertidal species present within the Gulf currently protected. They also do not form an effective network. Cape Rodney-Okakari Point became New Zealand’s first marine reserve in 1975. Within ten years snapper and crayfish populations re-established, previously decimated by overfishing, setting off a series of changes in the ecosystem of the reserve. Nowhere else on the coast teems with such a profusion of fish life that can easily be seen by visitors. The marine reserve has returned to what we imagine it would have been like prior to the arrival of humans. Cape Rodney – Okakari Point Photo © Tony and Jenny Enderby Tawharanui HAURAKI GULF Long Bay – Okura Te Whanganui – A – Hei Motu Manawa – Pollen Island (Cathedral Cove) Blue maomao Sponge habitat The sea boiled with kahawai and trevally over several feeding frenzy known in fishing circles as a ‘boil-up’ or ‘meatball’. squirts are among the creatures that live permanently attached to waters feeding on kahawai, sprats and other large fish. Meanwhile, “acres, screaming terns and gannets diving from above. The ocean seethes with life as a multi-pronged attack is launched: rock surfaces, competing for space as tiny particles of planktonic powerful orca come in close to shore to feed on stingrays. Close to home: Bryde’s whale Surface trevally rushed forward noisily, gorging themselves the fish are trapped near the surface by large predators such as food drift past them in the currents. The flow of plankton is on tiny krill. Into the surging sea surrounded by swarms of kingfish and common dolphins herding them from below, while simultaneously devoured by hungry fish such as blue maomao, silver bubbles, we powered down below the unsettled surface. avian predators such as gannets and shearwaters dive down from trevally and demoiselles. At dusk the nightshift plankton feeders Taking care Down past dark glistening bodies of frantic kahawai. above and pursue them underwater. such as bigeyes take over while the day feeders go to sleep. Down through plankton-feeding demoiselle and bright Larger algae or seaweeds are a food source for herbivorous or Humans are also top predators, using commercial and recreational blue maomao. Down past crowds of pink maomao, their grazing fish such as butterfish, marblefish and silver drummer, means to target their most favoured species from Gulf waters. colour faded whitish blue in the deepening light. Down the Power supply which have specialised ways of digesting the chemicals that the seaweeds contain. Spotties and other wrasses meanwhile feed on As a result, the numbers of many popular edible species like bottomless vertical wall. Sentinel kingfish cruised the void. the tiny snails and crustaceans that graze on the algal ‘fuzz’ that snapper, kahawai and kingfish have declined to a fraction of what Ghostly white hydroid fans punctuated the dark rock face. Surprisingly, the powerhouse driving this melee is made up of grows on the surface of seaweeds. Kina (sea urchins) use their they once were. Some, like hapuku or groper, were once the top Suddenly, staring with large saucer-eyes, was a huge groper millions of microscopic phytoplankton – single-celled algae. five-toothed jaws to graze algal mats directly from the surface of predator of inshore reefs, but are now considered a deeper water like a small cow. With two audible thwacks of his powerful Using the sun’s rays to produce energy, phytoplankton provide rocks. Groups of kina can form a formidable army, which can species. Entire habitats, such as the mussel beds that once stretched tail, he dissolved into the inky depths. Nitrogen narcosis was food for animal plankton, known as zooplankton. Some of literally mow down areas of the common kelp, Ecklonia radiata, from Waiheke Island to the Firth of Thames, have disappeared. kicking in. Time to get out of there.¹ these minute animals will spend their whole lives floating in the leaving a bare rock surface (‘kina barrens’) much like clear-felled Other human activities that have a major impact on the marine plankton. Others are the juvenile forms of more familiar marine forests on land. environment include sand dredging by the construction industry, ” animals such as crabs, shellfish, fish and sea urchins destined to dumping of harbour dredgings, urban development, farming and escape to a new lifestyle if not eaten first. forestry. Run-off from the shore, especially during heavy rains, Auckland’s own whale regularly sends plumes of brown sediment into the Gulf’s estuaries As daylight lengthens, the warming waters combine with Top of the chain an influx of nutrients from deeper waters and trigger a sudden and open waters, smothering delicate filter-feeding animals and Right on the city’s doorstep, a group of little known Bryde’s increase, or ‘bloom’, in phytoplankton numbers. Blooms blocking out sunlight that is so crucial to the health of seaweeds. Chemical pollutants from myriad sources can bind to sediments whales makes the Hauraki Gulf their home. A member of the bring about changes to the water’s clarity, giving it a ‘greenish’ Snapper consume a wide variety of foods found on rocky reefs, and enter the ocean through our waterways, often with unknown pod divides the waters of the Hauraki Gulf as it surfaces for air. appearance. Their timing is part of an annual cycle, feeding the switching prey as they grow. Armed with sharp teeth the larger consequences to marine life and to ourselves. Feeding on enormous quantities of plankton and small baitfish tiny larvae of many marine organisms over spring and summer. snapper are able to tackle heavily armoured shellfish and can such as pilchards and anchovies, these large baleen whales are a even crack open prickly kina. The large-lipped, but toothless red The sea is an important part of our lives. It provides us with kai sign of the abundance of life in the gulf. Sometimes the whales’ moki suck in seemingly indigestible coralline algae, extracting moana, inspiration, ancestral connections and valued recreational Photo © Rochelle Constantine huge flukes – extending out of the water as they lunge forward Wall of mouths the tiny animals that live among them and expelling indigestible and economic opportunities. Managing our extraction of its on their sides in open-mouthed feeding manoeuvres – can be particles through their gills. Crayfish emerge from their lairs at precious resources, and reducing the contaminants we release into mistaken for the enormous dorsal fins of orcas. it, is critical to the well being of the life it supports. Bryde’s whales reach up to 14.5 metres in length and 40 tonnes in weight. They are unique among baleen (filter-feeding) whales as they do not appear to migrate to feeding grounds night roaming widely to hunt shellfish, crabs, starfish and kina. in the Southern Ocean each summer and are thought to remain in waters warmer than 15-20˚C. The resident population in the Hauraki Gulf is estimated to number between 100- The schools of silvery fish moving together in a dance of Millions of reef-encrusting animals feed on the plankton soup Among the top predators in the Hauraki Gulf are dolphins such 200.