What is OneFishTwoFish?

One day, while eating a fish taco, it occurred to marine biologist and conservationist Dr Chris Gillies there might be a way to balance consumers’ seafood intake in much the same way as we do with carbon.

As the former Oceans Program Director at The Nature Conservancy and Science Director for the Earthwatch Institute, he’d worked to regenerate threatened marine ecosystems, including shellfish reefs and coastal wetlands, and helped corporate Australia adopt new sustainability practices.

Unfortunately, many of the solutions for replenishing our oceans are under-resourced or unrecognised. As a result, seafood lovers have no tangible ways of resolving the ethical dilemma about eating fish.

That taco was the impetus for OneFishTwoFish and Seafood Positive, formed by Chris in mid 2022 to encourage people to replace the fish they consume with new ones. In just a few months, a wide range of supporters, businesses and everyday people have joined the cause to make a difference, one fish at a time.

As well as running Seafood Positive & OneFishTwoFish, Chris is an Associate Professor (adjunct) at James Cook University and a member of the Australian Institute of Company Directors. He is a three-time Australian Antarctic Expeditioner, commercial diver and has published more than 50 scientific papers.  

Will you help us?

By becoming Seafood Positive and replacing the fish you consume with new fish, you’ll be doing your bit to help recover our oceans and make the world a better place.


Want to know more about the science behind returning fish to the sea? Visit our FAQs

Creating new fish overcomes the hurdles that prevent the natural recovery of fish and marine life. Most fish release millions of eggs but only a fraction of these ever make it to adulthood.

Eggs get eaten and young fish often fail to reach their nursery habitat where they can take shelter, forage for food, and grow into big fish.

Our projects focus on improving the size and quality of fish nursery habitats. Then, our assisted breeding programs increase the number of fish that can be replaced into their natural habitat.

This is the best way to help fish and marine life recover and thrive. An ocean teeming with marine life is possible within our lifetime.

What we do now makes all the difference.

It is entirely possible to reverse biodiversity loss in the oceans within our lifetime. Our strategy is to move towards a ‘circular’ seafood economy, where fish stocks are regularly replenished, and harvest is balanced with production.

We know this works because we have seen it happen in habitats all around the world.
But we can’t do it alone. Partner with OneFishTwoFish and we can change the state of our oceans.



OneFishTwoFish was created by Marine Biologist, Dr Chris Gillies, and is supported by a talented team of ocean lovers.

Dr Chris Gillies

Founder & Managing Director

Ivan Botic

Creative and Design

Tim Clarke


Lynne Hale

Conservation Advisor

Dr Philine Zu Ermgassen

Fish Advisor