Source: Radio New Zealand
Cockles are used as an indicator species to track the health of the harbour. Veronika Meduna
The wetlands and surrounding forests of Te Awarua o Porirua, or Porirua Harbour, were once rich food baskets for Ngāti Toa Rangatira. Indeed, it was the bounty of these waterways that convinced famed 19th century rangatira Te Rauparaha to bring his people south from Kawhia in 1820.
Ngāti Toa Rangatira kaumatua Te Taku Parai says there was lots of timber for building waka and whare, tributaries flowing into the harbour carried different foods, swamps provided plenty of harakeke, and greenstone could be found close by.
Sometimes, you can still see rays and rig sharks, and occasionally even pods of orca in pursuit of a meal in the inlets. But the harbour also carries the legacy of decades of development throughout the catchment – large-scale deforestation, road and rail building, and urban growth – bringing sediment and pollution in, and destroying natural habitats.
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Earlier this year, Ngāti Toa Rangatira signed a historic account with local and regional authorities to restore the harbour’s ecosystems, with a focus on stemming sources of pollution and reducing sediment flows.
Jimmy Young, Greater Wellington’s catchment manager for Te Awarua o Porirua, says his team is out on the harbour every week to meet with other groups working on the restoration. The two inlets – or “two lungs of the harbour” – are affected differently.
“One is far more rural and the other is far more urban,” he says. “In Pāuatahanui you don’t have those urban pressures, you have the roads but a much more natural shoreline. While in Parumoana, you have all the heavy infrastructure that’s been there for decades – railway lines and state highways that have straightened the shoreline, and a lot of reclamation of land.”
Young says the accord puts the harbour at its centre to better coordinate ongoing efforts, focusing on sites with the best chance of restoration. “It’s an inter-generation effort to restore the abundance of fish and healthy ecosystems.”
An aerial view of the two arms of Te Awarua o Porirua, with Parumoana inlet in foreground, Pāuatahanui inlet in the back. Wikimedia Commons
The regular cockle survey in Pāuatahanui inlet, run by the Guardians of Pāuatahanui, is one of New Zealand’s longest-running citizen science projects. Every three years, since 1992, volunteers come together to sample the inlet and count and measure the cockles they find.
Chair of the Guardians, Lindsay Gow, says the inlet has a variety of bird species and fish and is the main breeding ground for rig sharks in the western part of the North Island. “All of that needs significant protection, and the job of the Guardians is to do everything we can … to make people aware of the importance of the inlet.”
A cockle survey takes place every three years. Veronika Meduna
Te Taku Parai says the harbour once allowed Ngāti Toa to feed its own people well, but also to host manuhiri and treat them with kai moana. He says he won’t rest until the harbour is restored and has instructed the iwi’s rangatahi to compose a mōteatea (lament) to sing as a reminder of the important work ahead.
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– Published by EveningReport.nz and AsiaPacificReport.nz, see: MIL OSI in partnership with Radio New Zealand
