New technology ends pole method for Port Lincoln tuna fishing but industry in danger of overkill by 1980s

Ken Martin's statue of a tuna poler, celebrating the early method for hauling in southern bluefin tuna, was unveiled in Port Lincoln in 2019. Inset: The map of southern bluefin tuna's life migration around Australia.

European immigrants, particularly from Croatia, led the expansion of the southern bluefin tuna industry in Port Lincoln, using the line-and-pole method that the American/Norwegian Jangaard brothers had shown during their state government-sponsored visit in 1956.

By the early 1960s, three Australian fisheries – Esperance, Western Australia; Port Lincoln; and off the coast of New South Wales –  were catching 8000 tonnes of southern bluefin tuna.

While Australian tuna industry was getting started, the Japanese aggressively expanded their own fishing fleet that had been restricted until 1952 by the United States of America after World War II. The Japanese catch peaked in 1962 at 82,000 tonnes sold mostly in Japan and the Australian catch was canned for domestic consumption. A Port Lincoln cannery had opened in 1939.

In the late 1970s, Australia reworked the industry to drastically improve fishing efficiency. The arrival of the Haldanes’ Tarcoma vessel in Port Lincoln in 1952 had signalled the change to larger-scale fishing. The loss of the Lincoln Star (1961) and Smarda  (1963), each with seven on board, emphasised the need for bigger and better quality craft.

The brave but dangerous work of tuna polers gave way to purse seine fishing (surrounding the school of fish with a net). Boat design changed from United States to Norwegian design, better suited to rough Great Australian Bight waters. Chumming boats (releasing bait into the surrounding ocean) with purse seine boats enabled greater catches by pooling together. Spotter planes were introduced to find schools of southern bluefin tuna and direct vessels to then.

All these components increased the southern bluefin tuna catch to unprecedented levels. In 1982, the Australian catch peaked with 21,000 tonnes. At the same time, the Japanese catch of 40,000 tonnes was half its peak in 1962.

This confirmed what biologists had warned in 1979: the fishery was fully exploited. The parental biomass was found to be reducing at an alarming rate (30% of the level before intensive fishing) that would ultimately result in poor levels of juveniles to the fishery.

Despite warnings, the fishing pressure/effort continued into the early 1980s as fishing vessels continued to search the ocean for ever scarcer schools of southern bluefin tuna. In 1983, an Australian government inquiry found that the fishery was biologically overexploited and heavily overcapitalised.