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Investigating life in the sea – introduction

New Zealand is surrounded by the sea, and scientists estimate that as much as 80% of our known species are found in the seas around New Zealand. This marine environment not only provides a habitat for an estimated 65,000 species – it’s an important source of food and provides recreational and economic opportunities for our communities. Although we might think of the marine environment as separate from land, the two ecosystems are intricately linked – we are part of the marine food web whether we live on the coast or not.

Black coral underwater in Fiordland, New Zealand.

Black coral

Unusual conditions in Fiordland result in an abundance of black coral in the 15–40 metre zone. In other marine environments, black coral grows only at depths below 45 metres.

Rights: Stephen Wing, University of Otago

Let’s explore…

Let's go on a journey into the sea. Take a closer look at some of the organisms that live there and how they are classified. For example, we explore the extraordinary adaptations of sea stars, the importance of cockles and how to tell if a bryozoan is a plant or an animal.

Using a diving-PAM to measure photosynthetic potential of corals

Candida Savage diving

Diving is an important skill that Candida Savage uses when researching in the marine environment. In this photo, Candida is using a diving-PAM to measure photosynthetic potential of corals in Fiji.

Rights: Candida Savage, University of Otago

Find out more about where these marine organisms live as we discover some of New Zealand’s unique marine environments including estuaries, fiords and the continental shelf. Living in these habitats is often challenging, and marine organisms have evolved many weird and wonderful adaptations to cope with the variable environmental conditions in the sea.

Meet our scientists

Meet four scientists who are actively involved in research in New Zealand’s marine environment:

Overfishing is the primary threat for deep-water sharks and rays. Discover more about the research that has found that their long lifespans and slow reproduction rates make these species as vulnerable to overexploitation as whales once were.

Teaching and learning activities

On your journey into the sea, take time to try some of the activities:

Explore these activities and resources to learn more about New Zealand’s marine environment and discover some of the secrets of life in the sea.

Marine ecosystem

Explore this interactive diagram to learn more about life in the sea. Click on the different labels to view short video clips or images about different parts of the marine ecosystem.

Rights: University of Waikato

Citizen science

Using online citizen science opportunities as a way to deepen student learning and engagement is easier than you think.

  • Use Adrift to look at marine microbes drifting continually in our ocean systems.

  • Use Spyfish Aotearoa to discover, count and identify fish species that live within our marine reserves.

Read about these schools’ citizen science projects in the Connected  articles Down the drain and Sea science.

Question bank

The Investigating life in the sea – question bank provides a list of questions about life in the sea and places where their answers can be found. The questions support an inquiry approach.

Key terms

For explanations of key concepts, see Investigating life in the sea – key terms.

Timeline

Explore the timeline to look at some of the historical aspects of fisheries in New Zealand.

Published: 8 October 2009,Updated: 13 January 2023