Our Changing World

Wastewater testing became part of our daily lives during the Covid-19 pandemic, but what else can it tell us about what’s happening in our communities? From looking for illicit drugs, to monitoring alcohol consumption and health biomarkers, Claire Concannon meets scientists tapping into the rich research potential of what’s in our pee.

Read the article: 

Learn more:

• The Detail also did an episode on this topic in 2022, delightfully called ‘Spying on our sewage’
• For more about drugs and alcohol in New Zealand, watch/read/listen to Wasted and Proof
• Our Changing World also covered New Zealand’s world leading approach to Covid-19 sequencing during the pandemic.

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They will look like fish, swim like fish and even sense like fish. Liz Garton meets a research team designing robofish and smart wetsuits to monitor the state of our oceans.

Learn more:

• Claire Concannon checked out more of the Auckland Bioengineering Institute’s research last year in Digital twins and beating hearts.
• The podcast Voice of Tangaroa takes a deep dive into the state of New Zealand’s oceans.

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Making and processing music is something unique to human brains, says Dr Sam Mehr. But why are we so attuned to rhythms, melodies and matching tones? Claire and Sam take a deep dive into the universal language of music, and how our minds make sense of it.

Spotify is open on Dr Sam Mehr's work computer. He's halfway through Billie Eilish's new album, which he's enjoying. 

"I listen to every Billie Eilish album that comes out. I mean, she's great and it's kind of wild, why she's great to me." 

It's one of his side interests, homing in on supremely popular music to figure out the secret sauce of what makes it so well-liked. 

But his main research focus is the basic psychology of music - why and how our brains process music. 

The psychology of an everyday thing

Think of the space that music occupies in your life. Do you listen daily? On your commute? To get pumped up in the gym? Do you hear it all around - radios, cafés, the supermarket, TikTok videos? Maybe you sing or play an instrument. But have you ever stopped to wonder... why?  

"No species other than humans have something like music. Other species have vocalisations that might sound a bit like music, but they're very, very different in their functions and in their design than the human music faculty is," says Sam. 

"Just the fact that we're doing it in the first place is like, wait a minute, what's that about?"

Based now at the University of Auckland, Sam's own musical background paved the way for what he researches. He played piano from a young age, saxophone at school and then went to a music conservatory to study music education at third level. It was while running classes for very young kids with their parents that he started to ponder about the psychology behind it all.  

Is it a universal language? 

While a highly produced Billie Eilish album might be an entertaining listen, when it comes to answering the fundamental psychological questions about how humans interact with music, Sam focuses on more basic forms of music that have been around for much longer. 

Something he and collaborators have been working on for over a decade now is the Natural History of Song project - a collection of vocal music from all around the world, with recorded context for each piece of music. There are 118 recordings, divided into four categories - lullaby, love, dance, and healing songs. (You can explore the recordings in this interactive visualisation of the project.)   …

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Claire Concannon and Dr Andrew Digby talk about all things kākāpō: that habitat trial and where the birds are now, the next breeding season, and Andrew's hopes for the future of this iconic manu.

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In July 2023 four male kākāpō were released into the fenced Sanctuary Mountain Maungatautari - part of a new habitat trial to investigate suitable locations for the growing kākāpō population. But after a further six were introduced, the kākāpō began to wander - beyond the fence. A year on, and several escapes later, what's been learned? And what's next for kākāpō in Maungatautari?

There are plenty of night-time wanderers in New Zealand that you might expect to come across driving on back roads - rats, mice, a seemingly endless number of possums. 

But it's not often that you round a corner to come face to face with a kākāpō. 

Elwin's escapade

This was the surprising sight that faced Tyler James Lindsay very early one morning in January 2024. 

A Cambridge local, Tyler was driving a milk tanker along Scott Road, northeast of Sanctuary Mountain Maungatautari, when suddenly he saw before him a strange shape. 

"Just a big green bird. Just in the middle of the road looking straight at my lights, I think it was rather confused," he says.

Luckily, Tyler is into native birds, so he was aware that kākāpō had been introduced to the fenced sanctuary six months earlier. He knew exactly what he was looking at. 

The next day, Tyler's report made its way to Sanctuary Mountain Maungatautari kākāpō ranger Dan Howie, who quickly began the search for the elusive Elwin.  

"Such an incredible interaction that he saw this bird out there - in the middle of the road no less - which is absolutely terrifying as kākāpō ranger," says Dan.

But this was not the first time, nor the last, that Dan would feel that fear. 

The habitat trial 

Kākāpō numbers are growing. In 1995 there were just 51 kākāpō and the threat of losing them forever was all too real.

A decade ago, around the time that Dr Andrew Digby joined the Kākāpō Recovery team, there were just over 120 kākāpō. Today there are 247. 

Intensive management and three quite successful breeding seasons have enabled this doubling of kākāpō numbers in the last 10 years. Initially, the challenge was to save the charismatic, flightless parrots from extinction. Now, the team also has an added challenge: where to put them.

To date, the majority of kākāpō have lived on offshore predator-free islands in the rohe of Ngāi Tahu - Whenua Hou / Codfish Island next to Rakiura / Stewart Island, and Pukenui / Anchor Island in Fiordland. But these islands are getting full.  …

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An expedition to the Bounty Trough off the Otago Coast uncovers a treasure trove of deep-sea creatures - including some species new to science. Veronika Meduna meets slimy fish, snails, and tiny shrimp-like critters from the ocean depths.

The Bounty Trough is one of the world's least explored deep-ocean ecosystems.

Earlier this year, an expedition set off to explore this deep underwater rift valley off the Otago coast as part of the international Ocean Census project, under the umbrella of the United Nations Ocean Decade.

In partnership with Te Papa and NIWA, the voyage aimed to fill gaps in our knowledge of what lives in the deep. 

Hundreds of new species discovered

Onboard the research vessel RV Tangaroa were different sets of traps and samplers as well as a deep-tow camera system to allow the scientists to watch what goes on at depths of up to 5,000 metres. The expeditioners returned with hours of video footage and 1,800 specimens. Hundreds of them are new to science - including a slender, slimy bottom-dwelling fish known as an eelpout.

The number of new fish species may be countable on one hand, but Dr Rachael Peart expects to identify several new small crustaceans known as amphipods and isopods. They look a bit like tiny shrimp and dominate life in the deep ocean. 

Te Papa mollusc curator Kerry Walton has already identified 78 new species of snails and mussels from the Bounty Trough, including a parasitic snail stuck to a gummy squirrel - a weird sea cucumber with a large sail-like extension.

Te Papa fish curator Andrew Stewart says the museum's collection is limited to shallower depths of about 1,200 metres and mostly commercial species. Being able to explore the Bounty Trough opened up a treasure trove of sightings and catches from the deep. 

It also brought home the importance of ocean life.

"This is the world's largest habitat, by a vast margin. It plays a massively important role," he says. "We really need to know what's down there because shifts down there are the canary in the coal mine. We lose those, we're in trouble. Maybe not today, maybe not tomorrow, but we're in trouble."

Why explore the deep sea?

Professor Alex Rogers, the science director of the Ocean Census programme, says there are many reasons why we need to know what lives in the deep. 

About half of the oxygen we breathe is produced by tiny plants that live in the ocean. They also kick off the marine food web - from microorganisms to fish - which ultimately feeds millions of people.  …

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Avocado seed powder to make snacks, fish waste skin for wound healing, and bioactive compounds made from brewer's spent grain - Claire Concannon visits a food lab at AUT turning food waste into wealth.

Food is usually a no-no in a science lab, but this lab at the Auckland University of Technology is different.

One fridge is labelled 'beer research'. There's a drawer full of stick blenders, and a coffee machine.

"Well, it is a food lab," says senior lecturer Dr Rothman Kam. "It would be quite sad if you do experiments and were not able to eat the food that you make."

Food scraps to snacks 

Rothman and his food science lab group are interested in turning food waste into high value products (a process called 'food waste valorisation').

For example, tonnes of avocado seeds are a waste product of making avocado oil. Rothman and his team have set their sights on transforming seeds into snacks.

They've worked out a method of blending the seeds and processing them to make them fit for human consumption, resulting in an avocado seed powder.

This powder can then be added to breads or biscuits, or used with other grains to make puffy snacks. 

Arti-fish-al skin for wound healing

A second project, led by PhD candidate Edward Quach, is investigating the use of fish waste products to create artificial skin. This skin can be loaded with drugs to help burn victims heal faster. 

While the method of using fish gelatine in this way isn't new, Edward is trying a novel technique that bypasses the need to extract the gelatine, and instead goes straight from the freeze-dried ground-up fish waste to the jelly-like skin. 

A second life for spent grain

The lab's 'beer research' focuses not on the alcoholic drink, but on the spent grain generated in the beer brewing process. 

PhD candidate Ha Minh Quoc uses a freeze-drier to remove any moisture from the brewer's spent grain. Once he has dried out the grains, and ground them to a powder, he adds bacteria in. The bacteria (and the enzymes they contain) chop up proteins found in the grain, producing molecules with bioactive properties. 

These bioactive molecules are small bits of protein (peptides) that can carry out many different important functions in our cells. For example, bioactive peptides might help fight off germs, reduce high blood pressure, lower blood fats, act as antioxidants, or help ward off obesity, diabetes or ageing.  …

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Climate-change-induced sea level rise is happening. What will this mean for our low-lying wetlands? Will they get eroded away - releasing more carbon? Or will they grow at the same rate, and hold their ground? And what will this mean for the critters that live there? A team are investigating at an Otago wetland that might be the first in New Zealand to make this change.

From Lake Waihola, not far south of Ōtepoti Dunedin, fingers of water run down the plains, converging with the Waipori river coming from Lake Waipori.  

Dr Chris Kavazos, a freshwater technical advisor for the Department of Conservation, stands in one of these fingers. Waders on, he rummages in the muddy bottom for a logging device that has sat there for the last four months. 

Tracking the change

In that time, the device has been taking measurements of pressure and conductivity every ten minutes. From here, the water will complete its journey by joining the Waipori River, which connects with the Taiari (Taieri) river, and then empties into the ocean ten kilometres away. 

But it's not just a one-way trip. 

The area is extremely low-lying, just centimetres above sea level. Despite the distance from the coast, these waters experience tidal changes, and influxes of sea water. By measuring tiny pressure changes that equate to water depth, plus a conductivity reading that gives an indication of salinity, these logging devices are tracking the impacts of rising tides on these inland wetland areas. 

As sea levels rise - a result of human-induced climate change - these wetlands might be the first in New Zealand to experience significant impacts. Chris and others are keen to understand what it might mean for the area, and its inhabitants. 

The Waipori-Waihola wetland complex

From a map the approximately 2,500-hectare Waipori-Waihola wetland complex is easy to spot. 

Two lakes mark the north and south boundaries. The darker patches of lagoons, pools, swampy areas and meandering channels that connect them are easy to distinguish from the bright green rectangles of cultivated land that form the borders. 

And off a gravel road on the inland side of the wetland complex is a small collection of buildings – an office, accommodation, equipment sheds and a native plant nursery – this is the working space of Te Nohoaka o Tukiauau Trust…

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