Chatham / Challenger Project

Zoning the ocean into areas that reflect biodiversity for management purposes is a complex task. To date, progress has been made using physical oceanic data, but information about sea-bed ecology is largely missing.

The Chatham / Challenger project will map and compare habitats and diversity of sea-bed communities in fishable depths at key locations across the Chatham Rise and the Challenger Plateau.

These two areas have been chosen for the project because they provide a strong contrast in terms of plankton productivity. Their sea-bed communities are likely to mirror this.

This is a joint project between MFish, DOC, NIWA and LINZ. The $4.7 million project contributes to New Zealand’s Biodiversity Strategy.

Project Outcomes

To balance protection of the environment with the use of those resources it has become clear we need more information about the biological systems that operate in the ocean.

We already know about the distribution of fisheries and commercial fish stocks, and we know that deep water seamounts have fragile ecosystems vulnerable to fishing.

But we still know very little about the sea-bed communities that are found in soft sediments between 200 and 1200 metres deep - the depths and sediment types where our largest offshore fisheries are found (e.g. hoki, hake, ling and silver warehou).

We need to know more about the role of soft sediment communities in sustaining marine ecosystems and biodiversity, as well their role in sustaining our fish resources.

We also need to know how sensitive sea-bed communities are to disturbance. Mapping and characterising soft sediment communities in fishable depths is a step towards understanding this.

Information from the Chatham / Challenger project will:

Provide an important step towards mapping sea-bed habitats and communities on the Chatham Rise and Challenger Plateau.

Provide new information on the effects of trawling on soft sediment sea-beds.

Be used to improve decision-making around development of offshore Marine Protected Areas.

The Voyages

The first voyage, in 2006, acoustically mapped sea-bed habitats at key locations on the Chatham Rise and Challenger Plateau.

The second voyage, in April 2007, explored the Chatham Rise locations using deep-sea cameras and sample sea-bed communities using sea-bed sleds.

The third voyage, in June 2007, is exploring the Challenger Plateau locations using deep-sea cameras and sample sea-bed communities using sea-bed sleds.

Preliminary maps of biodiversity and the habitat types from this project will be available by mid-2008.