People's homes, jobs plus the fisheries and aquaculture sectors are at growing risk as climate change and human activity puts pressure on New Zealand's oceans and coasts, report says

As climate change and human activity puts growing pressure on New Zealand’s oceans and coasts, new research shows hundreds of thousands of homes, jobs and entire sectors are at increasing risk.

Research from a report called Our Marine Environment 2025, by the Ministry for Environment and Statistics New Zealand, shows the fisheries and aquaculture sectors, which contribute about $1.1 billion to Gross Domestic Product and support over 14,000 jobs, are being affected.

Alongside this 219,000 homes, representing $180 billion in assets, are already in flood-prone areas. And between 2026 and 2060, it’s estimated 1300 coastal homes (representing $900 million in assets) will experience greater than 20% damage in one or more extreme events.

These findings were published on Wednesday as part of a series and includes references to government reports, mātauranga Māori (Māori knowledge), statistics, published literature and peer-reviewed work.

The Ministry for the Environment’s chief science advisor Alison Collins says the report brings together the best available evidence to show how the marine environment is changing - and why it matters.

“For many people, the sea is part of daily life – whether through work, recreation, or cultural connection.”

Homes

The report says homes and communities are at increasing risk from rising sea levels and storm damage as changes in the ocean contribute to more extreme weather, flooding and inundation of coastal areas.

“Sea levels in New Zealand are rising, and extreme weather events such as storms are projected to become more frequent and severe. In low-lying coastal areas, higher storm surges are exacerbating the effects of flooding from heavy rainfall.”

The report says rising sea-surface temperatures in the Southern Pacific Ocean are providing more energy to drive extreme weather systems.

“The future will potentially bring more intense tropical cyclones and heavier rainfall, increasing risks for vulnerable communities in New Zealand.”

Increasing risk of damage and loss

Many of New Zealand’s homes and critical assets, think pipes and roads, are on the coasts, the report says.

“These are already vulnerable to the increasing damage and loss due to the cascading risks arising from coastal erosion and flooding,” the report says.

The report points to examples too - raising how a storm event in 2023 in Southland led to coastal erosion of about 5 to 30 metres along 1500 metres on the shore of the Waiau River estuarine lagoon.

The erosion also occurred in front of private properties on Bluecliffs Beach Rd, the report says, “causing a risk to these properties, with a potential loss of land, dwellings and outbuildings”. 

Alongside this, king tides combined with sea-level rise “will result in regular small-scale surface flooding and king tides coinciding with storm events will result in major tide-related flooding events”.

Insurance is also a concern with the report saying: “These increasing risks are likely to drive higher reinsurance costs for insurers, and higher insurance costs for households.”

This comes as consumer advocacy organisation Consumer NZ put out a report about insurance, saying if the country didn’t act now when it came to having a climate adaptation framework, it’s entirely possible many New Zealanders won’t be able to get insurance at all by 2035.

Alongside this, academics who specialise in insurance and its connection to climate told Consumer NZ the country has until 2040 before we start to see some insurers exiting Aotearoa and suggested some main centres could see insurance retreat by the end of the decade.

Infrastructure

It’s not only houses but roads, water pipes and bridges, things that are used to transport goods, keep communities connected and are critical for health and sanitation, are also all at increasing risk.

Figures from 2019 show 2273 kilometres of roads, 5572 kilometres of water pipes, 2457 square kilometres of land and buildings (with a combined replacement value of $26.18 billion in 2016) were vulnerable if sea levels rise by 0.6 metres.

The report also says sea-level rise, storm surges, coastal erosion and flooding are “just some of the effects of climate change that are expected to increasingly compromise wastewater infrastructure in New Zealand”.

“This will exacerbate other challenges facing many of our wastewater networks due to ageing, under-design and deferred maintenance.”

The report says there are nature-based solutions such as offshore reef and wetland restoration, which could reduce wave energy and store floodwaters.

Artificial reefs, seawalls and levees could also mitigate the effects of sea-level rise, the report says, “but are predicted to become increasingly difficult to maintain as sea levels continue to rise”.

In terms of fisheries and aquaculture, climate change is already affecting some species and ecosystems with the report saying marine heatwaves have already caused “substantial” decreases in fish catch “and large losses in farmed salmon and mussels”.

Warming sea temperatures and ocean acidification, when the ocean becomes more acidic because more carbon dioxide mainly from human activity is being absorbed from the atmosphere, may reduce the growth rate of some species like shellfish, blue cod and other large fish species.

“Conversely, ocean warming and marine heatwaves are likely to increase the abundance of some fish such as snapper and trevally - to a point, as these increases are likely to reverse if temperatures become too warm,” the report says.

There’s also concerns about diseases and marine life having poorer health in warmer temperatures.

Changing ocean temperatures have also created changes in how fish populations migrate and are distributed.

“This would have implications for Māori commercial fisheries, which hold about one-third of the interests in New Zealand."

“For example, warming south of the Chatham Islands since 2006 has placed the region in almost perpetual marine heatwave conditions, and could have implications for the orange roughy and hoki fisheries in the area," the report says.

Māori economy

The report says “marine environmental degradation linked to human pressures is resulting in the depletion of fish stocks, which directly affects Māori fisheries and the wider Māori economy”.

“These environmental pressures also directly affect customary and commercial fishing practices, reducing the health of key taonga species and disrupting mahinga kai and katiakitanga practices.”

The future of Māori customary fishing is at risk due to degradation of marine environments, impacting iwi Māori involved in fisheries settlements, the report says.

“Current pressures on fisheries impact customary fishing rights, as they limit opportunities for food gathering, weaken community ties, destabilise traditions and diminish connection to the environment.”

Tourism

In 2023, it’s partially estimated, due to limited data availability, that marine tourism and recreation employed about 1605 people and contributed $120 million to New Zealand’s GDP. 

“The natural environments that have supported the tourism industry, and the infrastructure that allows us to access and enjoy them, are at increasing risk,” the report says.

“For example, under one tourism climate change scenario, in which there is a disorderly reaction to climate change, with little policy action until 2030, projected risks include some coastal roads and popular visitor journeys being damaged intermittently.

“This scenario could result in unreliable visitor experiences, total loss of some experiences, and increased health and safety concerns for operators.”

So, what to do?

The report calls for a strategic approach and to prioritise areas “where better knowledge will make the biggest difference to decisions and outcomes” when it comes to better understanding the connection between climate change and marine environment changes.

To make this happen, the report suggests things like making data more open and accessible, and strengthening data through emerging technologies, integrating knowledge and establishing long-term measurements to detect shifts and trends.

It also suggests things like growing our knowledge of compounding pressures when it comes to climate change, bringing mātauranga Māori and tohu (environmental indicators) into coastal monitoring, and exploring coastal areas to get a better idea of the imminent risks but also opportunities.