Clues on how to manage sustainable ocean fishing can be found by looking back 700 years. Marine scientists investigated fishing yields since the 13th century in America's biggest coral reefs in Florida Keys and Hawaii made some surprising discoveries.
They found that by practicing effective eco-system management , the ancient fishing communities achieved higher yields than today and sustained fish stocks.
Study co-author and Colby College assistant professor of environmental studies, Loren McClenachan, says, "Ancient Hawaiian society effectively practiced what we now call ecosystem-based management, which is something that modern society often struggles to achieve. Incorporating some of these ancient techniques into today's policy may be the key to sustaining our fisheries."
The research, published in the Fish and Fisheries journal, was co-written by John 'Jack' N. Kittinger, from Stanford University's Center for Ocean Solutions. He explains that before Europeans landed, the natives in Hawaii caught fish on the reef in much greater quantities than those of today. This shows that high productivity can be combined with sustainability, as long as they are accompanied by effective management.
On the other hand, the reef fishermen in Florida went through many cycles of boom and bust, as well as low stocks of valuable species suitable for export.
Loren McClenachan says the Hawaiian fisherman employed conservation plans, such as protecting certain areas and limits on catching endangered species. The plans were agreed by the local fishermen and strictly enforced with harsh penalties such as capital punishment. No modern management system has managed to secure this kind of balance and it is common to see reduced resources, she says.
The team of researchers carried out in-depth reviews of the archives, which included records of numbers of species caught from the 19th century as well as population and fish consumption levels per head 500 years earlier.
They used various sources, such as native scholars, to discover the management systems employed. Those that were used during times of greatest yields were when the rules were strict and strongly enforced. Regulations based on class, such as keeping endangered species just for religious leaders and chiefs, were also observed.
The Hawaiian natives used methods previously used to keep fish ponds healthy to draw out nutrients and cut pollution on the reefs. Today, the solution is often to rely on large numbers of wild caught fish and to use antibiotics, which can cause greater pollution.
The study, called Multicentury trends and the sustainability of coral reef fisheries in Hawaii and Florida, highlights the U.S. National Ocean Policy as a holistic way of managing the sea's ecosystems and applauds co-management of local fisheries to ensure local communities are involved.
The Center for Ocean Solutions has about 80 scholars and educators who research coastal and ocean ecosystems. Colby College, based in Waterville, Maine, is one of America's oldest independent liberal arts college.