Seagrass secrets could help restore Queensland's coastal ecosystems

By Katelyn Dunn

Not all seagrass meadows are created equal, according to new CQUniversity Australia research that could help improve the success of restoration projects in Queensland and beyond.

Marine ecologist Elizabeth Andrews has discovered that even neighbouring seagrass meadows can develop unique traits that make them better suited to the environments in which they grow, a finding that could reshape how restoration projects source and plant seagrass.

Conducted through a collaboration between CQUniversity's Coastal Marine Ecosystems Research Centre (CMERC) and Deakin University, and supervised by Professor Emma Jackson, Dr Andrews' research focused on Zostera muelleri, an ecologically important seagrass species found throughout Australian coastal waters. Her work examined four genetically distinct populations within the Port Curtis region near Gladstone and investigated how environmental factors influence their growth, resilience and restoration potential. 

Dr Andrews said the findings challenged the assumption that seagrass from the same region could be used interchangeably in restoration projects.

"One of the key findings was that not every meadow is the same, even when they're located within the same estuarine system," Dr Andrews said. 

"We found significant differences between meadows in response to environmental factors such as light availability, wave exposure and sediment type.

"Those differences may influence how well seagrass performs when it's transplanted or used for restoration. It suggests restoration projects could benefit from matching source material to the conditions of the restoration site, rather than simply sourcing plants from the nearest meadow." 

The findings are particularly significant as coastal communities increasingly look to restoration as a tool for strengthening ecosystem resilience.

Seagrass meadows provide critical habitat for marine species including fish, crabs, turtles and dugongs, while also supporting fisheries, stabilising sediments, improving water quality and protecting shorelines from erosion. Yet despite their importance, they often receive less attention than other marine ecosystems.

Dr Andrews likens seagrass meadows to forests beneath the sea.

"Seagrass meadows are really the woodlands of the ocean," she said.

"They're full of life and support entire food webs. If people enjoy fishing, boating, snorkelling, seeing turtles or spotting dugongs, then healthy seagrass meadows play an important role in making those experiences possible." 

The research also highlighted the importance of preparing for future disturbances before they occur.

"Restoration isn't just about responding when a meadow declines," Dr Andrews said.

"It's about understanding these ecosystems now so we can act quickly and effectively when future disturbances occur. Having the right restoration material available and understanding where it performs best can help build resilience before it's needed." 

For Dr Andrews, the PhD marks the latest chapter in an unexpected career journey.

Originally from the Channel Island of Jersey, she moved to Australia and built a career in the corporate sector before making a major life change and beginning study as a mature-age student through CQUniversity's STEPS program.

After enrolling in an undergraduate science degree and completing a research project with Professor Emma Jackson, she discovered a passion for seagrass ecology that would ultimately shape her career.

"I always loved the marine environment, but I never thought becoming a marine scientist was something I could achieve," she said.

"Beginning my studies at CQU changed everything. What began as curiosity became a career dedicated to protecting and restoring coastal ecosystems."

Now based in Tasmania as a postdoctoral researcher, Dr Andrews is helping lead seagrass restoration projects that support one of Australia's rarest marine species, the critically endangered red handfish.

Looking back on her research journey, she says one lesson stands above all others.

"The biggest lesson I've learned is the importance of collaboration," she said.

"The challenges facing marine ecosystems are too big for any one group to solve alone. Researchers, communities, Traditional Owners, industry and environmental managers all have pieces of the puzzle, and when we work together, we get better outcomes."

Discover more research at CQUniversity's Coastal Marine Ecosystems Research Centre (CMERC).