As a graduate of the Bachelor of Marine Biology and PhD candidate at UTS, Mitchell spends his days doing what he loves: researching ways to conserve seahorse habitats and helping endangered or threatened marine species thrive.
Mitchell Brennan has been fascinated by the humble seahorse his entire life.
He’s one of those rare individuals who has known what he wanted to be since he was a kid. From exploring the water wearing floaties at the age of five, to now squeezing into scuba gear to study the depths of Sydney Harbour, Mitchell has made a career out of protecting his favourite animal.
“I’ve loved seahorses and sea dragons for a long time, and now getting to work with them – it’s about as close to a dream scenario as you can get.”
As a PhD candidate at the University of Technology Sydney, he spends his days in labs and in the water, researching ways to conserve seahorse habitats and help endangered or threatened marine species thrive.
But although he’s always loved the ocean, back in high school he wasn’t exactly sure how to translate this passion into a career.
Studying on land and sea
His journey to studying these fascinating creatures began at UTS Open Day when Professor David Booth, a leader in marine biology and seahorse conservation, gave a presentation sharing what it’s like to be a marine biologist, as well as his work studying sea dragons in Sydney’s harbour.
It felt like the perfect fit, and Mitchell commenced his undergraduate studies in marine biology at UTS.
Throughout his time as a student, he had opportunities to experience firsthand what it was like to be in the field doing research. During his third year, he took a trip to Heron Island in far north Queensland to study marine life in the Great Barrier Reef. It was a transformative experience.
Getting to complete some of my subjects on the Great Barrier Reef, in such an idyllic location, is an awesome way to experience research and actually get out into the ocean.
In addition to coursework, he accepted an undergraduate research internship in his final year, which Mitchell says was beneficial in confirming that life as a research scientist was ultimately what he wanted to do.
After graduating, Mitchell spent time in industry working with seahorses and other marine life in aquariums. While he says this was beneficial for helping him forge connections and gain confidence in his skills, it wasn’t long before research called to him again.
He thought back to his first intro to marine biology at Open Day, and pursuing a PhD at UTS felt like a natural fit given his interest in seahorses. Mitchell’s journey has come full circle, as Professor Booth is now his PhD supervisor.
“The research focusses at UTS were something I was drawn to and influential in my decision to do my PhD here,” he says.
"You want to work with people who are passionate about the same things you are. It’s a great opportunity to work with people who are experts in their field, but who are also able to motivate you and assist you with having genuine impact."
Mitchell has also paid it forward, welcoming undergraduate research students to intern on his projects and employing UTS graduates as research assistants.
Preserving seahorses for future generations
Now, Mitchell spends his days toggling between labs at UTS and field sites. At any given time, he’s diving to count seahorse populations, caring for seahorses in aquariums, installing seahorse hotels to help combat habitat loss and encourage population growth, analysing data, and more.
“The way I summarise my career is it’s dynamic – no two days are the same,” he says.
“It makes your work life pretty cool.”
Some of his time is also spent working with community groups, traditional owners and citizen scientists to communicate the important role Sydney’s seahorses play in marine ecosystems.
Sydney Harbour is home to two species of seahorses, one of which is endangered. It also houses sea dragons, pipe fish and other syngnathids.
“Seahorses are an indicator species – if there’s not habitat or food, there won’t be seahorses,” he says.
Mitchell feels they’re also a great mascot for marine life and getting people interested in preserving our oceans.
“They’re found in myths and folklore, they’re strange and unique, so I think everyone can gravitate towards them and they’ve become this charismatic species for getting people engaged with marine conservation,” he says.
Studying seahorses in the harbour also has personal significance for Mitchell.
“I learned to dive in Sydney Harbour and first saw the White’s seahorse when I was 18 or 19 – that was my first real interaction with them, and they’re now the species I work on,” he says.
I spend a fair amount of time diving in the harbour and seeing cool things. Sometimes I have to remind myself that I’m doing this as a job.
“Just knowing that my work is focused on having tangible impacts on a threatened species that I find to be amazing – I’m glad to have the opportunity to do that,” he says.
It’s a passion he plans to nurture long after he finishes his PhD.
“I’d like to keep working in a space that has real-world impact and positive effects on our oceans and the species that call them home,” Mitchell says.
“If I can work with seahorses and sea dragons forever that would be fantastic. I want to continue to support and develop our understanding of what we can do to support our endangered species and ecosystems.”
At UTS, the open water is Mitchell’s classroom.
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Mitchell Brennan
Professor of Marine Ecology
School of Life Sciences
