New Zealand The Land And Environment

The ancient supercontinent of Gondwanaland combined modern-day South America, Africa, peninsular India, Antarctica, and Australia. The islands now known as New Zealand split from the supercontinent roughly 80 million years ago, much earlier than other present-day continents, making it an isolated ecological time capsule. With few natural predators, New Zealand’s avian life evolved to occupy the ecological niches that mammals assumed elsewhere. They gained stronger legs, larger size, and many lost use of their wings. Two primary examples of these primordial birds—the Haast eagle (Hapagornis) and the moa—are now extinct. The giant Haast was the world’s largest eagle and dominated South Island’s food chain, and the moa was found on both North and South Island and was New Zealand’s chief grazing bird. The Giant Moa towered above the 11 other species of moa, standing nearly 3m tall. The country’s most recognizable bird, the thin-beaked kiwi also flourished on pre-human New Zealand.

Flora

Before 1800, 70% of New Zealand’s landscape was covered in the Gondwanian lowland forests, wetlands, and grasslands. Today, only 15% of the ancient forest remains. Despite this depletion, New Zealand is still home to a host of unique native plant life, nearly 2700 species. The most famous among these species are the towering kauri forests, which are among the oldest in the world. Although colonial loggers harvest 90% of the valuable original kauri forests to support the building of modern New Zealand, the kauri forests remain an invaluable asset to Northland’s tourist industry . The kauri are just one of a large family of podocarps, a class of conifers that includes other native trees such as the totara, rimu, miro, matai, and kahikatea. Such podocarps dominate many of New Zealand’s forested regions, forming many-layered forest canopies across North Island. Endless southern beech forests are more common on South Island; the famous Nothofagus genus can trace its roots to the forests that blanketed Gondwanaland. One hundred ninety-three different species of ferns have also left an indelible imprint on New Zealand’s flora. The mamaku tree fern can grow up to 20m in height; the ponga tree fern, with its silver-bottomed fronds, is the official national symbol. A few other distinctive plants make their mark on New Zealand’s landscape. The pohutukawa, “New Zealand’s Christmas tree,” has bright crimson blooms during late December and is found in northern regions. The rata begins life as a vine and slowly strangles its host tree to death until it casts a peachy-orange glow to the undergrowth with its bright blooms. The world’s largest buttercup, the Mt. Cook lily, and New Zealand’s only native palm trees, the Nikau palms, are other examples of the archipelago’s biodiversity. Alpine tussock grasslands on both North and South Island round out the diverse landscape.

Fauna

Many animal families that evolved on the supercontinent never developed in New Zealand. Most noticeably, New Zealand has no snakes, and three species of bats are the only native land mammals. Instead, the country has many strange and exotic birds. The four different species of kiwi are New Zealand’s most recognized celebrity. The small, solitary birds have slender beaks with external nostrils to help scrounge food from the forest floor during their nocturnal scavenging. Like many of their avian cousins, the kiwi is flightless, tail-less, and practically wingless. The kea, the world’s only alpine parrot, is one of the few birds to reside in the peaks of the Southern Alps. Any visitor to the ski slopes or national parks of New Zealand will quickly realize that the kea is no ordinary bird, but a clever, destructive, and bold menace. Watch your back—and your pack. The kereru, the native pigeon, is the only bird able to disperse the large seeds of some native plants. Some of the most recognizable New Zealand bird species include its seven types of penguins. Among them, the blue, yellow-eyed, and Fiordland crested are the most common. These fascinating birds are popular with tourists in Otago (p.385). Other fanciful names for New Zealand’s astonishing variety of birds abound: the morepork (ruru, the only native owl), the muttonbird (titi), the shag (kawau), and the wrybill (ngutuparore, with its slender and twisted beak), among others.

Today, many of these rare birds are endangered. Only 160 of the blue-green takahe, flightless parrot from the Australian continent, remain. The black stilt (kaki) are down to under 70. Fewer than 90 nocturnal kakapo, the world’s heaviest parrot (males can weigh in at 4kg), are still in existence. The sensitive bird is notoriously difficult to breed in captivity. Intensive conservation efforts operated by the Department of Conservation (DOC) and private organizations are underway for all three species, including the creation of predator-free sanctuaries on offshore islands and in remote wilderness areas.

Besides the birds, New Zealand is host to many critters that are both cringe-worthy and fascinating. 1500 species of land snails (some carnivorous), 11 species of the weta—the world’s heaviest insect, teeming crayfish (koura), pesky sandflies (te namu), and ethereal glowworms (titiwai) and their native habitats are all tourist attractions. The extremely rare coastal katipo spider, a relative of the black widow, is New Zealand’s only poisonous spider. Although people rarely encounter the katipo, the black spiders have a distinctive red stripe on the top of their abdomen and are usually found under logs or other debris. If you do get bitten, you should go to the hospital for an antidote. Although these spiders are poisonous, do not kill them—they are endangered, and will leave you alone if you leave them alone. Another primordial relic found in New Zealand is the tuatara, a lizard-like creature old enough to have roamed with the dinosaurs 200 million years ago.

Although land mammals are few and far between, there are plenty of marine mammals flourishing off New Zealand’s shores. Orca, seals, and sea lions can be found in the waters off South Island. The islands are also home to almost half of the world’s migrating whale, porpoise, and dolphin populations. Marine mammals unique to the area include Hector’s dolphins, beaked whales, the New Zealand fur seal, and the Hooker sea lion. At the turn of the century, marine mammal populations reached dramatic lows due to the lucrative whaling and sealing trades. While those early trades are no longer a threat to New Zealand’s marine life, climate changes and water pollution continue to threaten these animals’ habitats.

Invaders

Man’s arrival to isolated New Zealand brought about the massive destruction of natural habitats and the introduction of invasive, non-indigenous species. The first settlers from Polynesia arrived over 1000 years ago carrying with them breeds of disease-carrying dogs (kuri) and rats (kiore), ushering in the first age of extinction. The Maori, and later the Europeans, cleared forests for agriculture and hunted the giant moa to extinction. Deer, goats, pigs, rabbits, and opossums, brought to make settlers comfortable in unfamiliar surroundings, overwhelmed native species. Stoats and weasels, imported to control the exploding population of introduced rabbits, started feeding on hapless native birds when the rabbit and opossum supply diminished. Millions of years of evolution left New Zealand’s birds without any natural predators and no means of defense; even today, many bird species seem uncommonly friendly to tourists. Predation of native species continues to plague New Zealand. The kiwi is now vanishing at an annual rate of almost 6%. Wasps hidden in aircrafts entered the ecosystem during WWII and have since reached epidemic proportions, threatening the food of birds and endemic insects. In addition to losing 43% of frog fauna and over 40% of bird fauna since humans first arrived, New Zealand now has more than 600 endangered species.

Non-native flora has also disrupted the ecosystem by out-competing endemic flora for sunlight, space, and nutrients. These plants, accustomed to harsher weather, thrive in New Zealand’s mild climate. Because the introduced plants lack native predators, and because introduced predators often feed on indigenous plant life, the addition of a single foreign plant species can destroy an entire ecosystem. Of the 20,000 non-native species introduced to the country, the DOC reports that over 200 are now weeds.