Uncovering the secret lives of fish in marine national parks

In a research partnership between Deakin University andParks Victoria, marine scientists have captured rare video footage of fish and other marine creatures living on the seafloor off western Victoria.

Researchers have for the first time captured high resolution video of fish and other sea creatures in their natural habitat 100 metres below the ocean surface at Discovery Bay Marine National Park, 20 kilometres west of Portland. The video footage is part of a project to understand the links between the characteristics of the seafloor and fish communities across Victoria's marine national parks and sanctuaries.

"Ultimately we want to know what it is about particular areas along the seafloor that attract certain fish and other sea creatures," said Deakin's Dr Daniel Ierodiaconou, the project's lead researcher.

"Thanks to the latest in underwater video technology we are able to drop cameras to much lower depths than previously possible. The high resolution, continuous seafloor information we are filming is rare and for the first time we can see how marine creatures live on and near the seafloor."

The current project builds on Dr Ierodiaconou's previous work in mapping the habitats along the seafloor. It uses underwater video cameras called BRUVS—Baited Remote Underwater Video Station—that are dropped from a boat to the seafloor and can capture all movement within eight metres of the camera with an exact position on the seafloor recorded with GPS. The footage taken will be combined with the previous mapping data to draw a complete picture of life at the bottom of the sea.

"It is like a census of the fish population," said Dr Steffan Howe, Manager Marine Science at Parks Victoria.

"This project will tell us about what fish live where, how many of them there are, what their habitat looks like and how they interact with other species and across habitats. Projects like this one help us build on our knowledge of life under the surface in our marine national parks and provide us with the most up to date information to help in park management."

Initial analysis of the footage captured at Discovery Bay Marine National Park has revealed more than 40 species of fish. Further surveys will be carried out over the next three years at The Twelve Apostles and Point Addis marine national parks, and Merri Marine Sanctuary.