Where land meets sea, the Rena disaster – introduction

The resources in this collection are about where the land meets the sea. New Zealand has 15,134 km of coastline with extensive marine habitat. Land and sea are intricately linked, one impacting on the other – an ecosystem that needs care and protection.

Rights: Maritime NZ

Container from the Rena

The cargo vessel Rena is grounded on the Astrolabe Reef off the Tauranga coast. Tonnes of oil and dozens of containers are spilled into the sea, polluting the Bay of Plenty coastline.

In the early hours of 5 October 2011, the 236 m cargo vessel Rena struck the Astrolabe Reef about 12 nautical miles off the Tauranga coast and became grounded. The ship carried 1,368 containers, 1,700 tonnes of heavy fuel oil and about 70 tonnes of diesel in its tanks. Concern for the ecosystem rose as the stranded ship slowly split and spilled hundreds of tonnes of thick fuel oil and dozens of containers into the sea. This caused sickness and death in the seabird wildlife and polluted the Bay of Plenty coastline. After the emergency clean-up, the big question asked by everyone was, “How long would the environment take to recover?”

Learning from a disaster

Hub content developer Barbara Ryan used the Rena’s grounding as the context to develop a set of resources regarding the impacts of an environmental disaster, the consequences and responses. Barbara worked with Professor Chris Battershill and university students Nikki Webb, David Culliford and Alice Morrison. Chris heads the Coastal Marine Group at the University of Waikato and investigated environmental toxicity after the Rena went down. The students were already involved in surveying the Bay of Plenty coastline and collecting samples in relation to marine biodiversity and biodiscovery. The Rena disaster added another dimension to their research.

Key science concepts – biodiversity and habitats

The underpinning science concepts involve the marine environment. Although the articles use the Bay of Plenty as the location, the key science concepts apply to marine environments throughout New Zealand. Key articles look at biodiversity in the Bay of Plenty and how knowing what we have benefits marine science and innovation. Habitats is another key science concept – how marine life adapts to habitats and how it deals with stress caused by human impacts.

Cleaning up Rena – the aftermath

The Rena grounding had ongoing ecological impacts on the Bay of Plenty marine environment and the people who live there. Efforts by the science and local communities to clean up and restore the area and the effects it had on these communities are explained in these articles:

• Rena bird recovery
• Pollution from Rena
• Cleaning up the oil spill
• Iwi and kaimoana

Take up the challenge

The student activities explore the two key science concepts of habitat and biodiversity. Where do I live? looks at why and how marine animals and plants are best suited to particular habitats. The activity is ideal for rocky shore and estuary studies. With Introducing biodiversity, students make models of a marine ecosystem and then explore ways humans might impact on that ecosystem.

Two activities are associated with the clean-up effort. Responding to Rena uses video resources to help students consider short-term and long-term responses to an environmental disaster. Cleaning up oil in water experiments with sorbents, dispersants and cleaning oil from bird feathers.

Rights: Maritime New Zealand

Mixtures of contaminants can be potent

Mixtures of contaminants leached from the Rena could be toxic to marine life. Scientists look for signals in marine life that might come from such mixtures.

On the road to recovery

The Rena Recovery Project was declared complete in July 2015. The project noted that no new Rena-related oil wash-ups had been reported since March 2014. Local dotterel and penguin numbers were stable or increasing and Rena-related shellfish contamination was no longer an issue. In 2016, a commision of enquiry found that the Rena could be left on the Astrolabe Reef.

Find out more about the decision to leave the wreck remains in this Connected article.

In 2021 it was announced that the Astrolabe Reef will become part of the Mōtītī Protection Area, this means that the taking of any animal or plant will be prohibited. The goal is to combat the loss of biodiversity caused by previous overfishing.