What is a tsunami?

A tsunami is a series of broad waves in the sea (and sometimes in a lake). The cause is a movement on the sea floor – from an earthquake, a volcano erupting, or a landslide. Spreading like ripples from a stone thrown into a pond, they move outwards, travelling as fast as a jet aircraft. 

Impact on land

When they reach shallow water the waves slow down, but they become higher, sometimes 20 metres or more. They can be like a wall of water that crashes, or fast-rising water levels. They rush far inland for many minutes, moving faster than you can run. People caught by the waves often drown, or are killed by debris, and buildings are destroyed.

Tsunamis in the Pacific

Tsunamis can occur in any ocean. But most of them happen in the Pacific Ocean, triggered by the earthquakes and volcanoes there. Tsunamis over a metre high reach New Zealand about 12 times every century.

Some New Zealand tsunamis

• In the 15th century, tsunamis may have forced many Māori to move inland from the coast. A massive wave wiped out an entire village on D’Urville Island.
• In 1855, after a powerful earthquake, water in Wellington Harbour spilled on to Lambton Quay as the land moved and the harbour tilted. Large tsunami waves also rushed in from Cook Strait, at times leaving ships grounded on the harbour bottom.
• A local earthquake at Gisborne in 1947 caused a tsunami 30 minutes later. A 10-metre wave smashed a cottage, but no-one was killed.
• In 1960, a powerful earthquake caused a tsunami that killed thousands of people in Chile and across the Pacific. Boats, houses, and animals were lost as waves hit New Zealand's east coast. A few days later, coastal schools were closed and thousands of people moved inland when a tsunami was feared after a major aftershock of the earthquake.
• A magnitude 7.8 earthquake near Kaikōura in 2016 caused minor tsunamis along the east coast of New Zealand. The largest onshore waves, 6-7 metres, were recorded at Goose Bay, south of Kaikōura.

Warning of distant tsunamis

It could take 12 to 15 hours for a wave from a South American earthquake to arrive in New Zealand. The Pacific Tsunami Warning Center in Hawaii tells New Zealand if a tsunami is expected. Radio, television and internet announcements, phone text messages, and sirens warn people to move away from the coast.

Local tsunamis

If an earthquake near New Zealand triggers a tsunami, there may not be time for an official warning or sirens. If you are on the coast during an earthquake that is strong or lasts longer than a minute, hear unusual noises from the sea or see water rising or receding from the shore, move immediately to the nearest high ground or as far inland as possible.

Why does New Zealand have floods?

Flooding happens quite often in New Zealand, for several reasons:

• Weather systems are constantly sweeping over the country’s narrow islands, bringing heavy rain.
• The many mountain ranges cause moist air to condense and produce more rain. Parts of the West Coast, near the Southern Alps, get more than 13 metres of rain a year on average.
• The country is criss-crossed by rivers and streams that come down from the mountains.
• Since native forest was felled, heavy rain has flowed more quickly into rivers.

European days

The Europeans who began arriving in large numbers in the 1840s  did not know there would be frequent floods. Gold diggers in Central Otago often drowned or lost everything when rain-swollen streams swept their tents away. In 1863 more than 100 lives were lost.

More recent floods

Most New Zealand towns and cities have river flood problems. Floods continue to cause chaos and misery, costing millions of dollars to repair. Between 1968 and 2017 there were more than 80 damaging floods.

Floods can happen very quickly. After a few hours of heavy rain, a dry creek can become a raging torrent – called a flash flood. In 1938, the Kōpuawhara Stream near Māhia rushed through a camp of railway workers as they slept. Huts were hurled about, and 21 people died.

In February 2004, there were major floods in the lower North Island and Marlborough in the upper South Island. The Manawatū River burst its banks and helicopters rescued stranded victims. The cost was about $400 million. Then in July, parts of Whakatāne and Edgecumbe were swamped after intense rain, and more than 3,200 people were evacuated.

The remnants of two tropical cyclones (Debbie and Cook) caused widespread flooding, slips and power outages in Bay of Plenty and along the east coast of both the North and South Islands in April 2017. Edgecumbe was flooded again, forcing around 2,000 people to leave their homes.

In January/February 2023, the Auckland Anniversary downpour and the remnants of Cyclone Gabrielle caused widespread flooding, slips and power outages along the east coast of the North Island. Fifteen people died and more than 10,000 had to leave their homes. The final cost to the economy was expected to be more than $10 billion.

Can floods be prevented?

Floods cannot be totally prevented, but stopbanks and dams help control rivers. They may, however, also create problems. Regional councils check rainfall and water levels, issue flood warnings, and control how land is used in risky areas. Flood plains are likely to be regularly flooded, and it is foolish to build on them.

Early Māori diet

Before Europeans settled in New Zealand in 1840, Māori ate lots of fish – especially snapper, barracouta and red cod. Shellfish were also popular. Archaeologists have discovered the remains of shellfish such as pāua (abalone), pipi, mussels, limpets and cat’s eyes in ancient settlement sites.

Early European diet

When European settlers first came to New Zealand, they did not eat much seafood. They were used to the foods they had eaten in the United Kingdom and Europe, and preferred to send home for canned fish, or eat red meats such as mutton and beef.

By the 1930s, people of European descent still ate less seafood than Māori. Their recipes were basic – baked whole fish or fried fillets.

Favourite Kiwi fare

Fish and chips – from the working-class north of England – has been a firm Kiwi favourite since before the First World War.

Whitebait are young fish which swim into estuaries in spring. They are caught in nets and eaten whole in fritters. They are considered a delicacy.

Crayfish, kina (sea eggs), oysters and pāua are also delicacies. Toheroa was particularly popular in the early 1900s, when it was made into a thick green soup. It is now a protected species.

New flavours

Deep-sea fishing developed in the 1980s, and has become a big industry. Orange roughy and hoki are the main species caught and eaten. Scallops are also widely available. New Zealand aquaculture – farming and harvesting fish and shellfish – is a multi-million-dollar industry which produces salmon, oysters and mussels for local and overseas buyers.

Recent immigrants from Japan, China, Taiwan, Korea and South-East Asia have brought with them a taste for seafood. Even so, most New Zealanders continue to eat only small amounts of fish – usually as part of Friday night’s fish and chips.

What is the atmosphere?

The atmosphere is the cover of gases, including oxygen, that lies between earth and outer space. It reaches hundreds of kilometres above the earth. The atmosphere protects us from the sun’s rays, and controls the temperature around us. Without it, life could not exist. The layer of atmosphere where we live, and where the weather happens, is the troposphere.

What is an aurora?

An aurora is a beautiful display of coloured lights in the night sky. This occurs in the upper atmosphere. In the northern hemisphere it is called the aurora borealis, and in the southern hemisphere, the aurora australis. New Zealanders are most likely to see an aurora from the southern South Island.

What is the greenhouse effect?

This is the way the earth is warmed by the sun. Energy from the sun travels down through the atmosphere to the earth’s surface, where much of it is absorbed as heat. The surface then sends the heat back up. But some of this is held in the atmosphere by gases, keeping the earth warm enough for living things to survive – like a gardener’s greenhouse.

Why are greenhouse gases bad?

The gases that hold the earth’s warmth are called greenhouse gases. They include carbon dioxide and methane. In recent times human activities have upset the balance of these gases in the atmosphere. Cars and factories produce carbon dioxide, and so does burning down forests. Farm animals such as cows and sheep produce methane by burping, and New Zealand’s many farms produce a huge amount of methane. All the extra carbon dioxide and methane in the atmosphere is holding a lot more heat. This causes global warming. If it continues, life as we know it will be in danger.

The ozone layer

Ozone is a type of oxygen which forms a layer in the atmosphere. It protects us from the sun’s ultraviolet (UV) radiation, which can cause skin cancer. Ozone can be destroyed by chemicals released into the atmosphere from old fridges and other causes.

New Zealand: ozone and air pollution

New Zealand has very high UV levels in summer, and many Kiwis die from skin cancer. It is important to cover up in the sun, especially in the middle of the day.

The air is cleaner than in many countries. But Auckland’s traffic causes pollution, and Christchurch has smog in winter. To protect air quality, there are now rules about car exhausts and other pollutants.

The Kyoto Protocol

The Kyoto Protocol is an international agreement to deal with global warming. It was signed in 1997 in Kyoto, Japan. New Zealand and many other countries have agreed to reduce the greenhouse gases they are putting into the atmosphere.

Māori use of native plants

Early Māori tribes grew plants that they had brought with them from the Pacific as well as some New Zealand natives. They grew rengarenga lilies to eat their fleshy roots, and planted karaka trees around their villages for their orange berries. Although karaka fruits are poisonous, Māori knew how to process them so they were safe to eat.

European use of native plants

One of the first things European settlers did was clear native bush and plant European grasses. For a long time native plants were often seen as boring, or hard to grow. People in Britain were more interested in growing New Zealand native plants than New Zealanders were. British people liked common New Zealand plants such as cabbage tree because they seemed exotic.

There were always some people who loved native plants. J. G. McKenzie, who worked in Wellington’s parks department, planted so many pōhutukawa trees around the city that he was known as ‘Pōhutukawa Mac’.

In the 1970s and 1980s, people began to realise that they could make interesting gardens with natives. Today native plants are very popular because they are easy to grow and have interesting shapes and foliage.

Garden survivor

Tecomanthe speciosa is a climbing plant with big, glossy leaves and bunches of cream, bell-shaped flowers. It grows well in Auckland gardens, but only one plant survives in the wild, on a remote island in the Three Kings group.

New Zealand spinach

The only native plant that is still grown for food is New Zealand spinach or kōkihi. It has arrow-shaped leaves and is grown as a novelty vegetable.

What is biosecurity?

Biosecurity means protecting people, resources, plants and animals against harmful species from other countries. New Zealand’s native species and farming industry can both be threatened by new pests and diseases.

History

Early European settlers tried to stop human and animal diseases arriving in New Zealand. They built quarantine stations on islands, where sick people had to stay until they were better. Imported animals were also quarantined.

Farmers realised that some pests and diseases found in other countries were not in New Zealand. But settlers imported many plants and animals they thought would be useful. Some became serious pests.

Laws were passed to prevent or control pests and diseases – including scab (a sheep disease), the codling moth, which attacked fruit trees, and weeds that threatened farming. The government began inspecting fruit and plants arriving at ports.

Biosecurity today

In the 2000s biosecurity was managed at the borders by:

• inspecting and fumigating goods
• stopping people bringing organic matter into New Zealand – airports and ports have customs inspectors and dogs that can sniff out organic material, and have bins for throwing it away before people get to the customs desk
• spraying the cabins and holds of aircraft with insecticide.

However, some unwanted species still manage to get in – especially as trade and tourism increase. The painted apple moth, the Asian gypsy moth, and didymo algae have all been recently found in New Zealand.

Where possible, species are eradicated – or attempts made to slow their spread and reduce numbers.

Newspapers and journals

From the early days of European settlement, newspapers covered farming news. Journals informed farmers about animal, land and machinery sales, and tasks to be done on the farm. Farming families in isolated places relied on these papers for news.

Websites

Today, farmers can get information from the internet. There are many New Zealand websites about farming.

Radio

Radio broadcasts began in New Zealand in the 1920s. They soon became popular, helping farmers feel less isolated. City people also often listened to the programmes. William Goodfellow, founder of the New Zealand Cooperative Dairy Company, helped set up a national radio network.

At first, mainly music was broadcast – then news, weather forecasts and special farming shows began. From the 1930s, there were programmes for pupils of small country schools and Correspondence School pupils. After the Second World War more radio programmes were made for farmers, but these were cut in the late 1980s.

Television

Television began broadcasting in New Zealand in 1960. Like other media, it provided farmers with information and entertainment, and showed city people images of rural life. By the late 20th century, most New Zealanders lived in cities – but many still thought of the country as the ‘real’ New Zealand, and enjoyed watching programmes about it.

Country calendar was the first farming programme. It started in 1966, and was still going in 2022 – making it New Zealand’s longest-running TV show. It focused on personal farming stories, and sometimes played jokes on its audience.

Some drama programmes have been set in the country. In the 1970s, comedian John Clarke became famous as his character Fred Dagg, a farmer who wore a black singlet and gumboots and had a deadpan sense of humour.

Advertisements for products such as food and cars often appeal to New Zealanders’ fondness for country life.

In 19th-century Britain and Europe, wealthy people liked to go into the countryside and shoot game (wild animals such as deer, pigs and rabbits). They ate the meat, and displayed deer antlers as trophies.

When British settlers arrived in New Zealand, they found there were few animals suitable for hunting. So from the 1850s they shipped in deer and other animals, releasing them in the forests and the mountains.

Deer

New Zealand’s wild deer live in the bush, hills and mountains. The most common species is the red deer, which soon spread around the country. Other species include sika and fallow deer.

Other wild animals

Also hunted for sport were:

• tahr (related to wild goats)
• chamois (an antelope)
• pigs
• goats
• wallabies
• rabbits and hares.

Deerstalking

Stalking (hunting) deer was very popular in the 1920s, and rich Englishmen visited to capture large trophies. Hunters mostly used a .303 rifle.

Today hunters still head for the mountains in autumn, which is the time of ‘the roar’. This is the mating season, when many stags (male deer) have splendid antlers. The stags roar at each other and fight over the hinds (female deer). Hunters compete for the best antler trophies, using guns with telescopic sights.

Safety is vital, as sometimes hunters shoot each other by mistake, thinking they have seen a deer.

Too many deer

By the 1930s there were millions of deer, which were destroying native plants and trees and causing erosion. The government decided to reduce their numbers. Hunters known as deer cullers worked in remote areas, living in huts and shooting deer. By 1954 more than a million deer had been killed. Later, hunters shot them from helicopters – sometimes 300 deer a day. Government deer culling stopped in the 1980s, but recreational hunters help keep the numbers down.

Pig hunting

Wild pigs were hunted by Māori and Europeans, and today there are at least 25,000 pig hunters in New Zealand. It can be a dangerous sport. If a wild boar (male pig) is injured or angry it can attack and cause serious harm with its tusks. Hunters use dogs to find and hold a pig, and a rifle to shoot it or a knife to ‘stick’ it in the neck to kill it.

Māori and land ownership

Traditional Māori society had complex ideas about rights over land. Hapū (sub-tribes) and whānau (extended families) could have rights to use the same piece of land for different purposes. For example, one group might be allowed to fish in the stream, while another could grow food on the land nearby.

European settlers thought that once they bought Māori land, no one else had the right to use it. When Māori realised that, they began to question the sales. After the Treaty of Waitangi was signed in 1840, land commissions were set up to investigate earlier land sales. But much Māori land was either sold, or confiscated in the New Zealand wars of the 1860s.

European settlement

Many European settlers who came to New Zealand wanted to own their own land. In the North Island there were mainly small farms, and in the South Island there were sheep farms that covered large areas of land.

To help settlers get land for farms, the government bought land, often from Māori, to sell, lease or grant to the settlers.

Farm sizes

In the 1890s the government bought and broke up many of the biggest farms to create smaller family farms. In the 1940s and 1950s small farms were combined to make medium-sized family farms. During the 1990s, farms were joined up to make bigger farms, which were more efficient to run.

In the past people mainly farmed sheep and dairy cows, but now farmers have branched out into deer, goats, horticulture and forestry. Lifestyle blocks have also become common.

The importance of land

In recent years, Māori tribes have bought back land or had it returned as part of Treaty of Waitangi settlements.

Many people have been concerned about people from overseas owning New Zealand land, particularly in the high country of the South Island. There have also been concerns that high-paying tourists will have access to land, which will be closed off to ‘ordinary’ New Zealanders.