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Fisheries management
We work closely with the Australian Fisheries Management Authority (AFMA) to collect data on fishing activity and catches in waters around Australian Territories in the Southern Ocean. Scientific observers are present on all Australian fishing vessels, and collect important data such as:
- where fish are caught
- how many fish are caught
- size
- sex
- diet
Observers also tag toothfish and look for any recaptured fish, which provide important data on movement and growth of toothfish. Our research shows that several toothfish tagged around the Heard and McDonald Islands have been recaptured 1000's of km to the northwest, by French vessels fishing around Île Crozet.
Observers collect otoliths (ear bones) from toothfish. We prepare and analyse these ear bones to work out how old each toothfish is and how fast it has grown. Each ear bone grows in a series of layers, which appear as rings in slices cut from each otolith – just like the growth rings in a tree.
Close up of a tagged Patagonian toothfish.
Photo: AFMA | |
Tank full of Patagonian toothfish waiting to be tagged and released.
Photo: AFMA | |
Section of a Patagonian toothfish otolith from a 800 mm long individual -around 13 years old at capture.
Photo: Antarctic Division | | All of these data – on the biology and ecology of the fish captured, and how many, where and when they are caught are used to better understand the biology and population cycles of fishes, their linkages to other species in the ecosystem, and how many fish can be taken in each season by the fishery.
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