Different systems of knowledge – together, stronger

Researching my book The Science of the Māori Lunar Calendar has deepened my appreciation of Mātauranga Māori and its importance to the lives of New Zealanders past and present. Not long ago, Māori knowledge was largely disregarded by the scientific community and treated as little more than myth and superstition.

Today there is a greater awareness of the wealth of accumulated knowledge that allowed Māori to adapt and thrive – from the use of sophisticated star maps for navigation to a recognition of celestial patterns that marked the passage of time. Sustainable resource management took the form of rāhui (temporary bans) to protect depleted ecosystems, while in-depth botanical knowledge was the basis for rongoā Māori (traditional medicine). These were just the tip of an iceberg of ancient wisdom that researchers are still uncovering today.

For centuries, a bedrock of Mātauranga Māori has been the lunar calendar or maramataka (literally ‘the turning of the moon’) which formed an integral part of Māori life and was used to regulate hunting, fishing, planting, and harvesting. Similar versions of the calendar can be found throughout Polynesia where they have been modified to reflect local conditions.

As Māori had no written language, the calendar was essential for monitoring seasonal changes, the migration of fish and birds, and the flowering of plants. It also dictated when to plant and harvest. Like the appearance of the Matariki, monitoring the phases of the moon had practical value in the struggle to survive.

One practical application involved fishing. For instance, some fish are more active or abundant during certain tidal fluctuations which are influenced by the moon’s gravitational pull and allowed Māori to predict good and bad fishing days.

Two separate studies by statisticians at Auckland University have found a link between a popular Māori fishing calendar and fish catch. Dr Russell Millar found a relationship with recreational fishing for snapper. Although the effect wasn’t dramatic, snapper stock would have diminished since Māori developed the calendar, so the effect may have been substantially different years ago when overfishing was less of a problem.

Another study, led by Dr Ben Stevenson, found a similar correlation. He and Millar write that “a fishing trip undertaken at the most successful point in the cycle will have an expected catch 13.7 percent greater than a corresponding trip at the opposite point of the cycle”.

Over the past decade there has been a resurgence of interest in the calendar coinciding with the Ministry of Education’s push to give indigenous knowledge equal standing with scientific knowledge. Many popular books and social media sites on the maramataka have emphasised the more obscure aspects such as the belief that certain phases can affect everything from a person’s mood and energy levels to their ability to concentrate.

Wiremu Tāwhai’s Living by the Moon, and Hinemoa Elder’s Wawata Moon Dreaming are prominent examples. These beliefs played a relatively minor role in traditional Māori society as the primary purpose of the calendar revolved around food security and survival. Despite this, many Kiwis now routinely follow Māori calendar apps that predict ‘high’ and ‘low’ energy days.

Several teachers are using these ‘energy levels’ to determine which days are best to conduct assessments, and which are optimal for sporting activities, while others use it to predict days when students are likely to misbehave. The mayor of Kaikohe, Moko Tepania, uses the calendar to schedule meetings on days deemed less likely to trigger conflict. Some government-funded health clinics are not only using it to help their staff manage the ‘high’ and ‘low’ energy levels of each month, but their patients’ mental health problems and everything from quitting smoking to diabetes and depression.

Unlike with fishing, the science behind these claims is on shaky ground. Contrary to popular belief, there is no significant correlation between the phase of the moon and an increase in hospital admissions, police calls, crime, or unusual behaviour. In New Zealand there is a popular belief that serious mental health events such as depression and suicide cluster around certain phases of the Māori calendar. Yet a 2025 study led by Auckland University anaesthesiologist David Cumin and biologist Nickolas Matzke examined 22 years of data and found no significant correlation either for the overall population or the sub-group of Māori. This is in line with international studies on the effect of lunar phases and behaviour.

With so many Kiwis using the calendar to guide their physical and mental wellbeing, it is essential that these therapies be evaluated by western medicine. The impact of the Māori lunar calendar on health needs to be validated. Until this occurs, patients can be encouraged to use the maramataka in conjunction with scientifically supported therapies.

We owe it to our whānau to determine the efficacy of these treatments. This is not an attack on the status of Mātauranga Māori, but a call for collaboration between different systems of knowledge. In the words of Auckland University Vice Chancellor Dawn Freshwater, “mātauranga Māori and Western empirical science are not at odds and do not need to compete. They are complementary and have much to learn from each other”.