Seaweek 2005

Student Information Sheet 9 - Commercial Shark Fishing

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Glossary

Sharks have been fished for thousands of years. In primitive societies, they were caught with wooden or bone hooks for their meat and livers. Their teeth could be used as weapons or tools. Over time, uses have been found for most parts of a shark's body. The skin can be used for leather for shoes or belts, jaws are taken as souvenirs, the flesh is eaten, the carcass can be used for fertilizers, the fins in soup and liver oil is a rich source of Vitamin A and has been used in medicines and cosmetics.

Why is there concern over fishing for sharks?
What fishing methods are used to catch sharks?
World catches increasing
Shark fishing in Australia

Why is there concern over fishing for sharks?
Sharks are often difficult to identify and so catches recorded by fishers in logbooks do not tell you what species it is. There has often been no recording of bycatch that is thrown away. The lack of information makes management of shark fisheries more difficult.

Most sharks and rays grow and reproduce slowly and are late to mature compared to bony fishes. This means that shark populations are at risk because of fishing and are slow to recover if over-fished. Sharks need careful management if shark fisheries are to be sustainable. Many shark fisheries throughout the world have brought about rapid stock decrease and collapse.

What fishing methods are used to catch sharks?

Gillnets
This is the most common fishing gear in shark fisheries. They are suspended vertically in the water near the surface or near the sea floor. The size of the holes in the nets depends on the species being fished. The nets are usually several hundred metres in length. They are left in the water for two to six hours and are then hauled in.

Shark gillnet vessel with net deployed
(© Bureau of Rural Sciences, Australian Fisheries Resources, 1993)

Shark gillnet vessel returning to port in
southern Australia (© Albert Caton)

Shark gillnet vessel at the wharf in Darwin
(© Kevin McLoughlin)

School shark-a species targeted by the
Australian Southern Shark Fishery
Image © Ken Hoppen Photography

Longlines
These are one line that can be several kilometres long. Baits are attached to the line at regular intervals as it is being set from a moving boat. Longlines can be set at various depths in the water. Shark fishers generally set their lines on the sea floor with anchors to keep the line in place. Tuna fishers set their lines above the seafloor and although they do not target sharks they catch a lot as bycatch.

Trawling
Trawlers tow a net along the seabed. Trawlers usually target fish and prawns rather than sharks; however, they can be caught in high numbers as bycatch. Bycatch has been reduced by using special equipment that allows large animals to escape from the net.

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