Marine biodiversity in New Zealand

Many of New Zealand’s species are endemic – they are found nowhere else on Earth. This makes New Zealand’s biodiversity very special in the world. This includes marine biodiversity – for example, 90% of New Zealand’s marine molluscs are found only in New Zealand. Understanding biodiversity is important because it shapes our national identity, underpins our economy and has intrinsic value. It also allows us to track the wellbeing of our ecosystems.

Research in biodiversity

Professor Chris Battershill, the University of Waikato’s Chair in Coastal Science, is leading research to explore marine biodiversity in the Bay of Plenty, including the functions of marine ecosystems. This involves recording biodiversity, understanding how it is maintained and examining the stresses and strains that may be impacting on it. The research explores how diversity may add to the resilience or buffering of our ecosystems in order to keep them healthy.

One outcome of these studies found that marine organisms have developed complex biochemical machinery to protect themselves and cope with changing environments. These findings have led to conservation projects and to generating ideas for new areas of innovation based on bioactive chemicals.

Conservation projects

The conservation projects involve examining human impacts on the environment and how marine ecosystems could be protected. One example is a recent large set of projects related to possible impacts of pollution from the Rena. Other projects will investigate sensitive marine areas – ecosystems that are already under stress and that may need more management to enhance their resilience to changes in the environment.

Of special interest are biodiversity ‘hot spots’ or areas where biodiversity is exceptionally high. There are a number of these hot spots in New Zealand – in these places, 60% of the species are found nowhere else in the world. One such hot spot is in the Bay of Plenty. In this hot spot, warm water currents meet with cold water currents so marine life includes both subtropical species and cold temperate species.

The projects will look at how the biodiversity changes over time. Research in Australia shows huge changes in biodiversity of the seafloor plant and animal life where waters have warmed in response to changing currents. The Bay of Plenty research will look at changes of marine life in a comprehensive and detailed way. This hasn’t been done in a marine environment in this country before where all aspects of the ecosystem, including the microbial ecology, are examined.

If we don’t protect our biodiversity, we will not be able to seek clues for treatments of new diseases and environmental problems of the future.

Innovative ideas

Sustainable aquaculture

The research has helped identify new methods for aquaculture, particularly for producing food and biofuels. The aim is to create sustainable marine farms in new ways, for example, farming plant-eating fish (like butterfish or the ‘sheep of the sea’) instead of carnivores like kingfish. Also, seaweeds have been identified as a growth industry for biofuel. They yield 24 times more biofuel extracts than palm oil.

Both the food and biofuel products could be grown in the same farm with a better environmental outcome. For example, fish, mussels and algae could be grown together. They all provide nutrients for each other and could be developed as a micro-ecosystem. In this way, their environmental carbon footprint is reduced as well. This type of farming is called integrated multi-trophic aquaculture (ITMA).

Novel byproducts

New Zealand’s marine biodiversity produces a living chemical warehouse. Well over 10% of our marine species can generate biological chemicals offering potential for biodiscovery. The uniqueness of our organisms has made such research a high priority. For example, many algae and metazoans (encrusting animals such as sponges) survive by generating biological chemicals to protect themselves. These chemicals have applications in agriculture (such as pesticides) and medicine (such as anti-cancer drugs). Marine bacteria are also a focus within the research. Because they evolved over 4 billion years, Chris identifies them as a chemical library worth studying, “so that we can get clues as to how they survived using their defensive chemistry, which gives us insight into how we may develop useful chemicals for our own use”.

New Zealand has already pioneered three out of 30 current anti-cancer drug leads in the world from marine sources. The most significant of these drugs was developed from a sponge found on the Kaikōura Coast.

Internationally, there is a 0.000001% chance of discovering a useful chemical from a marine organism within an exclusive economic zone (EEZ). New Zealand’s success rate is 2% – enormously high by comparison. Even if these discoveries don’t develop into a drug, they still generate a lot of income because they may inform future drug leads and they build capacity in this country for other high-technology endeavours. Many can be used in other applications such as biomedical, industrial or veterinary products.

Chris relates our success to the marine diversity in New Zealand and to the approach taken. Scientists were not blindly looking for useful marine organisms. Rather, they worked out how organisms were surviving in nature first and then used this to work out how they might use that ability to help people.