Mangrove law change proposed for Whangateau

A large number of mangroves have established in the Waikokopu Estuary following the construction of the Omaha causeway in 1971.


 

Mahurangi residents living on the Whangateau Harbour may soon be able to remove mangroves without resource consent, as Auckland Council has indicated support for a relaxation of the rules.

Under current rules, resource consent is required to remove mangroves taller than 60cm, but under the Proposed Auckland Unitary Plan (PAUP), the removal of mangroves that have established since 1996 will be allowed.

Council representative and NIWA scientist, Dr Carolyn Lundquist, and the Omaha Beach Community (OBC) have recommended Whangateau Harbour be exempt from the regulations and mangrove removal be allowed back to 1948 levels, which will be determined from aerial photos from the time.

The topic was heard by the PAUP independent hearings panel earlier this year.

In her evidence to the panel, Dr Lundquist said mangroves were encroaching on seagrass and saltmarsh habitats in the harbour, and removing mangroves would only have a minor impact on the environment. The construction of the Omaha causeway in 1971 created an artificial environment which allowed mangroves to propagate in the Waikokopu Estuary, to the south of the causeway. However, if the mangroves were removed they would have a low chance of re-establishing, she said.

The OBC commissioned ecologist Dr Grant Dumbell to complete a study on mangroves in the harbour to support their submission. Dr Dumbell said aerial photography of the Whangateau Harbour from 1948 and 1953 shows that historically there were few mangroves in the harbour.

Removing mangroves back to 1948 levels is “not only desirable, but critically necessary for the recognised ecological and amenity values of this harbour to be protected and … to restore and preserve the natural character and ecological integrity of the harbour,” he said.

Under the proposal, areas at Tramcar Bay and Horseshoe Island in Whangateau would be excluded from the removal zone.

OBC president Peter Hooper says the changes would not result in wholesale removal of mangroves.

“We are not anti-mangroves, we just want them controlled in a rational way. If a landowner has half a dozen in front of his property, they should be able to remove them without having to get a resource consent.”

Several groups submitted in opposition to the proposals.

Mahurangi marine biologist Dr Roger Grace presented evidence on behalf of Forest & Bird and the Environmental Defence Society. Dr Grace said mangroves provide an important habitat for fish and birds, including banded rail.

“Mangroves in the Whangateau enhance the range of recreational experiences available, and provide unique opportunities to explore a very different habitat amongst the mangroves, by snorkelling, kayaking, or stand-up paddleboarding.”

He said the lack of mangroves present in 1948 was likely due to the number of cattle which grazed on mangroves in the estuary at low tide in the early 1900s.

The independent hearings committee is expected to make recommendations to Council in July next year.