Marine life in need of care and protection
Aotearoa’s marine environment is a taonga (treasure) of natural, cultural, recreational and economic importance. It underpins our marine economy, including fisheries, aquaculture and marine tourism.
Our seas are 15 times New Zealand’s land area. While around 10 per cent of our land mass is protected as public conservation land, less than 0.4 per cent of our Exclusive Economic Zone is protected in no-take marine reserves.
Alan Eggers, from Trans Tasman Resources (TTR), claimed in a recent opinion piece that the company has the marine and discharge consents it needs to start mining the seabed in the South Taranaki Bight. This is incorrect.
For the last seven years, Te Runanga o Ngati Ruanui Trust, Nga Rauru , Kiwis Against Seabed Mining, Forest and Bird, Fisheries Inshore NZ, the NZ Federation of Commercial Fishers, Talley’s Group, LegaSea and many others have vigorously contested TTR’s proposals.
The Supreme Court is now considering the issue, with its decision expected within the next few months.
These organisations have all opposed TTR’s plans because of seabed mining’s potentially significant impacts on what they value about our oceans.
In a giant experiment which hasn’t been trialled elsewhere, TTR wants to vacuum up 50 million tonnes of black ironsand each year. It wants to do this over a 66-square kilometre area 22 to 36 km offshore from Pa tea.
It proposes to anchor a large mining ship to process the ironsand at sea. Some 10 per cent of the sands would be processed into iron ore concentrate with the other 90 per cent pumped back into the sea causing a huge discharge ‘‘plume’’ of suspended sediment. And TTR wants to be able to do this around the clock for 35 years.
The deep sea environment is the least explored and largest ecosystem on earth. Seabed mining hasn’t been done before. The full extent of its likely environmental impacts is uncertain, yet scientists around the world have expressed serious concern about the harm a constant sediment plume could have.
On land, we understand the harm that sediment pollution from earthworks, urban development and vegetation clearance causes to streams and estuaries and aquatic life.
Across Aotearoa, progressive farmers, iwi and hapu¯ , and community groups are planting riverbanks to trap sediment and nutrient pollution and improve the health of waterways. Yet TTR is proposing to dig up and discharge tens of thousands of tonnes of sediment every day.
Of the 12,820 species described for New Zealand’s marine environment, over half are endemic – they are only found in the seas around Aotearoa.
The seasonal concentrations of krill in the South Taranaki Bight mean that it’s a hotspot for marine mammals such as Pygmy blue whales, orca and southern right whales.
The Taranaki coast is also home to Maui’s dolphin — our rarest marine mammal — and bottlenose and Hector’s dolphins. What impacts will the sediment have on them and the species they feed on?
The fishing industry is concerned that the sediment plume and mining noise would cause fish to avoid key fishing areas, such as the Graham Bank.
The sediment plume would also reduce light in the water column, affecting growth of phytoplankton, critical to the marine food web. The persistent 24/7 underwater noise from the large suction dredge and processing vessel could disrupt communication for marine mammals and other marine life.
The executive chairman of TTR describes the opposition to seabed mining as short-sighted. I disagree. A ban on seabed mining allows a long-term view.
If we want to avoid the ongoing loss of marine species and biodiversity, the increasing warming, acidification and rising seas caused by a changing climate, we need to protect the oceans as our largest carbon sink.
The Green Party has proposed a 10-year moratorium on all forms of seabed mining, including dredging iron sands.
A moratorium would allow time for a robust assessment of whether seabed mining can or should occur anywhere in New Zealand’s ocean space, and if so, under what conditions. It would allow research into potential environmental effects and the rollout of comprehensive marine spatial planning.
Maori Party co-leader Debbie Ngarewa-Packer has a member’s bill before Parliament which would prohibit seabed mining around Aotearoa/New Zealand. It deserves to go to select committee so public views can be canvassed.
Over the last 200 years the oceans have absorbed a third of the carbon dioxide produced by human activities and 90 per cent of extra heat associated with global warming.
Oceans have a huge role in mitigating climate change.
Rather than allowing the large-scale disturbance of seabed mining with long-lasting and potentially unforeseen consequences, oceans deserve our care and protection - because we depend on their good health.