Global lessons across our largest ocean | UniSC | University of the Sunshine Coast, Queensland, Australia

A marine iguana rests on a volcanic rocky shore in the Galápagos Islands, warming its leathery skin in the sun after diving into the cold ocean in search of food. More than 12,000kms away on a tiny coral cay in the Great Barrier Reef, a black noddy seabird searches for leaf litter to build its nest in the sweltering Queensland heat.

On the surface there seems little to connect the two.

Yet both are contributing to a search for answers by University of the Sunshine Coast researchers that could be vital to their survival – and the health of our blue planet.

It has been almost 190 years since Charles Darwin, aged just 22 years, devised his theory on the biological origins of life after noticing the unusual diversity between the creatures he encountered on a voyage along the South American coast.

Now an evergrowing contingent of young PhD candidates and undergraduate students, led by UniSC academics, are following the world’s most famous biologist to Galápagos, seeking their own incredible journey of scientific discovery.

Australia and the Galápagos lie at opposite ends of the Pacific Ocean, with ecosystems and species as widely different as the seas between them, but are linked by a changing climate, shifting species and the growing scourge of plastic pollution.

Out in the field, they are measuring blue whales, wrangling sea lions and marine turtles for blood tests, tagging sharks and manta rays, and taking genetic samples from bottlenose dolphins.

These activities are part of a diverse range of studies helping to build a detailed baseline picture of the health and connectivity across the ocean of some of the world’s rare and threatened species.

“We need to further our discoveries and find solutions to some of the most pressing issues facing our planet, and Galápagos’ relatively pristine environment provides an unparalleled opportunity to do this." Professor Ross Young

What Darwin could never have imagined

On land, the Galápagos flightless cormorant – with its tiny wings evolved from no longer needing to fly – resembles an ungainly duck.

It’s an endearing sight watching a male devotedly waddle the shore searching for ocean debris to decorate its nest.

Once seaweed, sea stars, sea urchins and other ocean items decorated their nests to attract a mate. Now, many are filled with plastic.

Just how this is impacting on these birds, and other seabirds in the Galápagos is the focus of research by UniSC PhD student Alice Skehel, with supervisors Associate Professor Kathy Townsend and Dr Dominique Potvin.

Both the flightless cormorant and the lava gull have been highlighted as high risk of being impacted by pollution.

“We are asking how it impact their general and population health, and breeding success," Alice said.

Initial findings are alarming

"We found these vulnerable species have toxic chemicals in their bodies.”

“We also suspect that the flightless cormorants are actually more successful at achieving a mate because the nests are so attractive filled with blue ropes, discarded cameras, flipflops and other apparently appealing items.”

The study builds on collaborative research that reveals the disturbing extent of pollution in the Galápagos from the millions of tonnes of rubbish that enter the world’s oceans each year.

“In this most untouched natural wonders, rubbish is washing up on every one of its 13 major islands, including those that are isolated and uninhabited," said lead author Juan Pablo Muñoz-Pérez, who completed the research as part of doctoral studies at UniSC.

It is a sight that would have been unthinkable when Darwin first sailed into the archipelago.

Photo Credit: Juan Pablo Muñoz-Pérez

More than 50 species, including 20 found nowhere else on earth, were found to be regularly consuming and becoming entangled in plastic debris.

“Green sea turtles, marine iguanas, whale sharks, medium-ground finches, Galápagos flightless cormorant and manta rays are facing the greatest threat of serious harm from entanglement,” he said.

“Our Santa Cruz tortoise, green sea turtle and Galápagos marine iguana are most in danger of ingesting plastic.”

Poisoned by plastics?

A vital next step was to determine if exposure to plastic toxins was making these animals sick.

In one finding, the daily ingestion of microplastics by the sampled green sea turtle populations varied from zero to a staggering 2610 pieces.

“Our team measured the amount of plastic pollution in these at-risk species by taking their vital signs and blood samples to compare with standard health metrics,” Mr Muñoz-Pérez said.

“We found even when pollution is not visible to humans, it is becoming a silent, emerging contaminant for some species."

“And while all animals appeared clinically healthy, suppressed immune systems were observed in those with the most plastic accumulation.”

This research is the first to use both health and plastic pollution metrics to understand the threats of plastic contamination on Galápagos wildlife, providing essential baseline data for future comparisons.

UniSC is conducting similar world-first research in marine turtles along the Queensland coast, providing important insights on the extent of the problem of plastic toxicology across entire populations.

Too hot to handle

Suited up in scuba diving gear, UniSC Associate Professor Kathy Townsend dives into the waters off Lady Elliot Island at the very southern tip of the Great Barrier Reef. Her heart sinks.

The water is warm. Too warm.

Temperatures on the reef flats are soaring into the high 30s and reach into the high 20s at depth.

“The corals on the reef were under stress. Colonies bleached white or showed bright florescent colours as they lost their symbiotic algae. In some areas, up to 90 percent of the corals were bleached,” Dr Townsend reflects.

“It was so hot that it was even uncomfortable for me as I snorkelled. Something I had not experienced before.

Yet the heatwave sadly did not come as a surprise.

Last month was expected to be the 15th consecutive month of record-breaking global ocean temperatures, with marine heat waves described as “off the charts”. The forecasts for what could follow are unprecedented.

It's one of the great evolutionary challenges facing our ocean. And Galapagos is in the crosshairs.

Its many islands sit at the intersection of three ocean currents, a convergence that brings very nutrient rich, cool waters to the region, and makes it very susceptible to climate variability, particularly from El Niño events.

In the past, extreme events have devastated the archipelago. Alarming numbers of iconic wildlife perished, marine iguanas, Galápagos penguins, fur seals, flightless cormorants, as well as corals.

Seabirds stopped laying eggs and abandoned nests, and invasive plants took over native vegetation.

Mighty lessons from a tiny island

The Galápagos archipelago, with its 13 main islands and chain of 100 smaller islands and islets, is a powerhouse of evolution.

By comparison, Lady Elliot Island is literally and figuratively just a speck in the ocean.

Yet this tiny coral cay - once stripped back to bare rock by guano mining in the 1800s - is punching well above its weight, revealing new insights into species shift, a changing climate and regeneration.

Species entirely new to science, others never observed in Australian waters and tropical marine life found where they do not usually belong.

These are among the latest startling discoveries from the unique research Leaf to Reef project led by UniSC on the island, that sits at the southern end of the Great Barrier Reef.

“We expected it would be a decade or more before we found new tropical marine animals and bird life moving here in search of cooler waters, when we started four years ago to establish a baseline to measure biodiversity and climate change, " Dr Townsend said.

It's happening now.

"As the heat in our seas intensify, our latest findings confirm the island’s critical role as refuge species move from the equator to escape."

At last count, the research team had confirmed more than 660 species on and around the island and surrounding reefs, including bird counts that uncovered the world’s oldest recorded red-tailed tropic bird and 14 new migrant species.

The research project is also linked with ongoing restoration project on the island.

“And as marine heatwaves become more common, intense and longer lasting, Lady Elliot is the perfect place to gain insights and knowledge of the actions we can take to safeguard against growing challenges facing our ocean," Dr Townsend said.

What the birds can tell us

Across the world seabird populations are in heavy decline, not only from a warming seascape, but from habitat loss, introduced predator species and competition with fisheries.

These birds are the ‘canaries in the coal mine’ as UniSC researchers seek to establish population baselines and gain new insights on climate change and plastic pollution impacts.

The black noddy is one of most easy-to-spot seabirds on Australia’s Great Barrier Reef islands, found in their thousands during breeding season.

Populations in the southern reef make up 20 percent of global numbers.

It is also known as a seabird "wreck species", prone to mass die-off events, most recently in 2021.

Zerra Edgerton is tracking the marine tern as part of her UniSC doctoral research.

"We suspect the birds starved to death due to food scarcity, typically linked to changes in oceanic conditions from El Niño events," she said.

“With their intensity and frequency of these events predicted to increase, it will impact on seabird populations that rely on access to near-shore foraging waters – and future generations,” she said.

“The more we understand about the way these animals use their habitat both on land and at sea enables us to form the best plans for conservation."

Evolution in motion

The marine iguana, found nowhere but the Galápagos, looks like a prehistoric punk rocker and is a superstar in the lizard world as the only one that can swim in the sea.

As an undergraduate, UniSC Alumni Kate Berry had the invaluable opportunity to travel twice to Galapagos, and to Florida as part of a team seeking to uncover new insights on evolution by studying the locomotion of these iconic creatures.

Led by UniSC’s Dr Christofer Clemente, the study was surprised to find that it had not changed the way it moved in order to inhabit its environment, compared to lizards.

Photo credit: Kate Berry

“Understanding movement strategies of these animals is key to understanding which habitats are most important to them – and thus which we should focus on preserving.

“This is true not only in the Galápagos islands, but across the globe."

Looking at the bigger picture

Imagine getting as close as possible to a 200 tonne blue whale, the largest animal on the planet, while being tossed about in choppy waters in a three metre inflatable boat.

"It really is the ultimate rush,” says Galápagos Science Centre researcher Daniela Alarcón-Ruales, who is seeking to better understand how climate variability affects the largest animals in the ocean as part of her UniSC doctoral studies.

Yet, helping the Galápagos through what some describe as its greatest evolutionary test is not just a professional interest for Ms Alarcón, and her partner Juan Pablo Muñoz-Pérez.

It’s also deeply personal.

San Cristóbal island is where the marine biologists live and raise their daughter Brisa.

“There is still hope, especially for the future generations,” said Mr Muñoz-Pérez.

“Our daughter, Brisa, was literally born in the water and had learned to swim and fall in love with the underwater world since the age of one year."

Together, towards a better future

Collaboration is vital to answer some of the most pressing environmental issues the Galapagos, Australia and the wider world faces.

Professor Ross Young says UniSC is in the privileged position of being able to foster international research with partners and embrace being global citizenship that contributes towards a better tomorrow.

“This underpins the strength of our commitment to use our resources and expertise to have impact in the Pacific and do all we can to contribute to aligned United Nation’s sustainable development goals.”

UniSC is a member of the International Galapagos Science Consortium, a group of global institutions dedicated to studying and preserving the archipelago, through collaborative, interdisciplinary research.

The University of North Carolina at Chapel Hill and the Universidad San Francisco de Quito lead the group, with partners University of South Alabama and James Cook University.

The thread of Darwin’s theory of natural selection, based on this remarkable chain of islands, sets the theme for over 30 collaborative research papers published so far.

“And we are scaling up what we are doing in future,” Professor Young said.

“We are continuing to investigate critical areas such as the genetics and evolution of species, plastics ingestion and toxicology, the origin of debris choking our oceans, and the invasive species threatening the world’s islands.

“We are seeking to show how traditional island wisdom and Indigenous knowledge can help set a research agenda.”

Many of the research and citizen science projects are led by UniSC’s Ocean Future Research Cluster and UniSC Marine and Terrestrial Megafauna Research Cluster.