Tauranga-based producer Justine Murray dons some gumboots and meets some teeny-tiny cockles as she joins a team surveying the Waihi estuary. Professor Kura Paul-Burke is weaving mātauranga Māori and western science together to address questions that local iwi have about the health of the estuary, and what can be done to improve it.

There are many signs in the taiao (natural world) if you look close enough. Like when the tōrea (oystercatcher) strikes at low tide looking for food; these birds love shellfish, crabs and tuangi (cockles). But how long does it stay? And what is the relationship of the bird to what's around it?

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That's just a glimpse into the tohu surveys (observations) that Professor Kura Paul-Burke and her research team are carrying out as part of the research project 'Tāwharautia te wahapū o Waihi - Protect the Waihi estuary' supported by Our Land Our Water and led by Te Rūnanga o Ngāti Whakahemo.

For generations this estuary was used as a mahinga kai (food gathering place) but over the years the water quality has declined, due to increased pathogens and sedimentation, much of which comes from four neighbouring water canals. Kura, the country's first wāhine Māori Professor of Marine Science and Aquaculture, based at the University of Waikato, argues the straighter the canals are, the more likely pollutants or paruparu makes its way into the estuary.

As the water quality declines, the loss of species also means the loss of mātauranga Māori. Kura and her team draw on both western science and Māori knowledge systems in this study.

Integral to the harbour is the nana (seagrass) meadows. Nana is a kōhanga (nursery) and a foraging habitat for young snapper and trevally, but it is decreasing at an alarming rate.

In 1943 nana meadows were plentiful in the Pukehina district. Today there are just two discrete beds left - this impacts the feeding habits and survival rates of tuangi (cockles).

Kura and her team are on a mission to assess the health of the estuary and figure out what needs to be done. Producer Justine Murray joins the team at Pukehina to learn more.

To learn more

Justine Murray spoke to another of Kura's PhD students last year about the resilience of crayfish in Tauranga Harbour.

Listen to 'Collaborating to move freshwater species' to learn about weaving mātauranga Māori and western science together for conservation translocations.

Hear more about using these two knowledge systems together in 'A bridge between science and mātauranga Māori' and 'The science of Matariki'…

Go to this episode on rnz.co.nz for more details