By Susan Milius
Economists say that their computer models could bring peace, at last, between the fisheries industry and conservationists.
The models show that cutting back on fishing until a marine population rebounds, a dream of conservationists, also maximizes profits over time, says Quentin Grafton of Australian National University in Canberra. He and his colleagues found that after populations recover, profits rise. When fish are abundant, catching the quota takes less time and requires less fuel. The increased profits eventually compensate for industry losses during the prior period of restraint, Grafton and his colleagues say in the Dec. 7 Science.
The team’s computer models show this scenario working out in all of the four fisheries studied. In three populations—big eye and yellowfin tuna in the Pacific and prawn north of Australia—stocks could rebound in less than a decade. More remarkable, says Grafton, is that the economic scenario also plays out in orange roughy, which would need decades to rebuild their population.
An expectation of future profits should allow for schemes to ease the pain during the initial period of restraint, says Grafton. For example, a program might compensate crews during the stock-building phase but collect a share of later profits.
Economists had previously talked about the possibility that marine abundance would boost profits, but Grafton and his colleagues say they are the first to show the dramatic influence of what is called the stock effect.
Even before publication, their analyses convinced Australia to adopt a delayed-gratification policy for prawn fisheries, starting in 2008.
