Leigh students conduct research to combat climate change

Students at Leigh School have been at the forefront of a collaboration between NIWA, Auckland University of Technology and the Goat Island Discovery Centre that could have global implications.

With help from the students, the scientific consortium is studying the movements and frequency of salps, a jelly-like barrel shaped ‘planktonic tunicate’ you’ve most likely overlooked while swimming.

According to NIWA ecologist Dr Moira Decima, the reason salps are important is because they capture and trap carbon, which could have positive implications for climate change.

Salps consume carbon-rich plankton and convert it into a dense faecal pellet that quickly sinks to the bottom of the ocean, where it can stay for a thousand years, effectively removing carbon from the atmosphere.

“Because salps combine their swimming and feeding mechanism, they can filter a lot of water in a short time, making them efficient at sequestering carbon,” Dr Decima says.

Dr Decima came from California to New Zealand in 2015 to study zooplankton and was surprised to find that salp blooms are a regular part of the ecosystem in Leigh. They are generally considered an anomaly in other parts of the world.

The reason why they are commonplace here is a mystery and has been the subject of Dr Decima’s most recent research.

A team of snorkel-clad student researchers from Leigh School have been brought in to collect data on when and where salps appear.

From the research vessel Tangaroa, Dr Decima was able to fill the students in on her work, provide regular blog updates and answer questions via video.

An app that allows the students to communicate with Dr Decima was designed by AUT app lab director of research and development, Dr Claudio Aguayo.

It allows users to take a picture of the salps they have observed and send the information straight to Dr Decima.

Dr Aguayo says the project is part of a broader movement towards ‘citizen science’ using technology to bring together scientific researchers and the wider community.

Leigh ‘citizen scientists’ on the job.

“Researchers can’t be everywhere, but bringing in the community leverages a wide group of people who know their local area,” Dr Aguayo says. “It also increases awareness of environmental issues.”

Although the school students didn’t manage to find salps at Goat Island on a snorkelling trip last month, 10-year-old Noah Write did sight them at Mathesons Bay.

“The most interesting part was finding out what salps were, because I thought they were just fish eggs,” Noah said.

His interest in salps, which involved making a video and a model salp, made him realise how important they are for the environment. Noah says he wants to become both an artist and an ecologist when he leaves school.

Teacher Rachael Waterhouse says the project has been great for taking a big global idea like climate change and making it local for students so that they can understand it.

“Kids are more environmentally conscious these days and it is important for them because it is the world they will be living in,” Rachel says.

“But you have to make sure it’s not too doom and gloom because they are just kids, which is why this project is perfect.”

Leigh residents are invited to join the project and can get involved by downloading the app at app.salpcount.nz


Nature’s carbon eaters

Salpa thompsoni are commonly found in the sea around Leigh.

Salpa thompsoni, commonly known as salps, are sea creatures that appear as a gelatinous blob. Classed as urochordates, they have a primitive spine made from cartilage. Salps move around via jet propulsion, contracting muscles which pump water through the body.

The water is also strained through filters, feeding the salp with phytoplankton. In the Leigh area they have become a regular part of the ecosystem, with fish such as oreo and warehou specialising in preying on them.

This is unusual because in the United States, salp blooms are only present during El Nino warm water events. To make things even stranger, salps reproduce both sexually and asexually. At the start of a breeding cycle, a salp reproduces asexually by producing a chain of buds, which each separate and mature into a fully grown female.

These females will then be fertilised by a male and give birth to a single embryo which will start the process again. After giving birth to the embryo, the female grows testes and functions as a male fertilising future females.

Sources, Dr Moira Decima, NIWA and others.