Above the bush line
Despite the challenging landscape and harsh climate, some native animals make their homes in the alpine zone.
New Zealand’s black mountain ringlet butterfly looked so like a European one (Erebia epiphron) that it was classified as the same. Scientists later realised it was a distant cousin, placed it in a different genus, and renamed it Percnodaimon merula. Species of native edelweiss also look almost identical to the European edelweiss, but belong to another genus. These are examples of ‘parallel evolution’ – where life evolves in similar ways in comparable yet separate environments.
Three species of bird live almost exclusively in the mountains: the South Island’s large kea parrot, a native pipit and a rare, tiny rock wren which, in winter, forages under the snow. This last one is a living fossil with no close similarities to any other living bird (except the rifleman).
Other animals living high in the mountains are: alpine versions of geckos and skinks, spiders, dragonflies, cockroaches, wētā, grasshoppers, cicadas, flies, moths, flatworms, and a giant snail.
Wetland and freshwater animals
Animals living in rivers, streams, lakes, bogs and swamps include bitterns, harriers, wrybills, stilts, gulls, crakes, shags, kingfishers, fernbirds, grebes, teal, scaup and other native ducks.
Three kinds of native eel, a lamprey, two smelt species, seven species of bully and 25 species of galaxiids are found in New Zealand waters. There are also kōura (a small edible crayfish) and, more rarely, freshwater mussels.
Many insects, such as mayflies, stoneflies, dragonflies, caddis flies, mosquitoes, midges, and sandflies live in the water or mud as larvae, but emerge to fly as adults. Water spiders run across the surface of streams while beneath swim water beetles and water boatmen. Many waterways carry the water snail Potamopyrgus.
If a sandhopper is picked up and released in the sand dunes, it hops back across the beach towards the sea. If released a kilometre inland, it will still hop back to its beach. Catch a sandhopper on a Canterbury beach, on the east coast, and release it on a West Coast beach and it will hop back towards the east coast.
Many animals live on New Zealand’s sandy and rocky coasts. The most notable of the birds are gulls, terns and shags, but dotterels, sandpipers, plovers, herons, spoonbills, kingfishers and 57 kinds of wading bird feed on the beaches and estuaries. Many of the waders are migratory, arriving for the summer to feed at estuaries and shell banks. For example, 100,000 godwits migrate annually from Siberia and Alaska. Over 50,000 gannets nest round the coasts.
New Zealand’s only venomous animal, the katipō spider, lives in dunes behind sandy beaches. Abundant sandhoppers and kelp flies feed on rotting seaweed.