Marine biodiversity and biodiscovery

Nikki Webb, a student at the University of Waikato, worked on a summer research scholarship collating an inventory of biodiversity for Tauranga Harbour. This was a collection of plants and mostly unarmoured (no shell) animals within three marine ecosystems. Samples were split to provide specimens (identification vouchers) for museums, and a subsample was frozen to be analysed later for bioactive chemicals (for medicinal drugs and agrichemical discovery).

Biodiversity laws relating to the biodiscovery process

Nikki first endeavoured to find out what New Zealand laws existed around collecting these marine samples, with a special focus on Treaty of Waitangi considerations. She wanted to ensure she was collecting according to cultural, ethical and environmental protocols. She spent time looking up legislation and talking to librarians about science and Māori law. Nikki discovered that there are no specific laws about collecting biological material from the sea. She did learn, though, that the Ministry of Economic Development became aware of the need for a specific law for collecting New Zealand marine samples in 2007 and is working with iwi to make such a law. They are working with the Waitangi Tribunal and the Convention on Biological Diversity. The new law will address issues of ownership of samples, intellectual property and traditional Māori knowledge.

Collecting the samples

Nikki collected samples from three different marine environments:

• Leisure Island (Moturiki, Mt Maunganui) – a rocky shore.
• Rabbit Island (Motuotau, Mt Maunganui) – a rocky reef (these samples were collected by diving).
• Waikareao Estuary (central Tauranga) – this area was divided into mangroves (a muddy area full of mangroves) and sandflats (a more open area with a sand base rather than mud).

The samples collected from these areas included seaweeds, sea lettuce, sea squirts, sponges, anemones and algae.

Although there are currently no laws about collecting these samples, Nikki was careful to observe some common-sense rules:

• Her collection was minimal (20 items from each area – a total of 60).
• She did not take any rare samples – only those that were in abundance.
• She removed items carefully so as not to disturb the surrounding area.
• With some items such as sponges, she took half, leaving the other half to grow back.
• She took small portions of algae, seaweeds and sea grass – leaving the majority to grow back.

Voucher samples for museums

These samples were taken to the Coastal Marine Field Station at Sulphur Point in Tauranga. Here, the samples were identified and labelled along with details about the samples (such as their colour and smell) and the ecosystem they were found in (such as the tidal condition and temperature of the site). One of each of the best looking samples, known as voucher samples, was preserved in isopropyl alcohol (IPA). These samples will be passed on to museums. The remaining samples of each species went into the freezer with tracked labels linked to the voucher.

Biodiscovery – looking for bioactive chemicals

At a later date, the frozen samples will be analysed for bioactive chemicals. These are natural chemicals found within an organism that have an effect on the physiology of other organisms. Scientists are particularly interested in the pharmaceutical (medicinal) and agrichemical (natural herbicide and pesticide) properties of these chemicals. A database of known bioactive chemicals has been collated, and scientists seek these in organisms that can be easily grown and harvested.

Nikki is interested in finding two particular bioactive chemicals:

• An active ingredient for anti-cancer drugs.
• An agrichemical – a natural bacteriocide against Pseudomonas syringae pv. actinidiae (Psa), a bacteria that kills kiwifruit vines.

A silver lining to the oil spill

Some of the samples collected were taken from polluted areas. Run-off from around the Waikareao Estuary contributes to a build-up of mud, nutrients (fertiliser) and pesticides. The samples collected from Leisure Island were collected not long after the container ship Rena was shipwrecked near Tauranga Harbour. Spilt oil was visible on the rocks from where the samples were collected from Leisure Island.

The reason Nikki collected mostly unarmoured (without shells for protection) animals was that, when under threat, these animals often give off a chemical defence, especially if there are pollutants around. These chemicals have a high chance of being bioactive. If an animal is confronted with pollutants (oil or fertilisers) that may threaten its life by causing disease, the animal may release bioactive chemicals to protect itself. These are the same chemicals that may be of use to us.

Consulting iwi

An important aspect of this project is that it incorporates consultation with local iwi. As iwi share their local knowledge with Nikki, she will share outcomes of her scientific data with them.