Cal Poly-UCSB Study Proposes Closing the High Seas to Fishing — with Surprising Results
March 25, 2014
Contact: Crow White
The blue areas in the image above represent the high seas —
international waters where fishing is unregulated.
It's not every day you get to please economists and conservationists, but Cal Poly Biology Professor Crow White and his colleague Christopher Costello, a professor at UC Santa Barbara, might have done just that. According to their article in PLOS (Public Library of Science) Biology, closing international waters to fishing could more than double the populations of migratory fish species. The surprise came when they found that fisheries' profit levels could also double while their yields increased by more than 30 percent.
Migratory species in unregulated international waters, known as the high seas, pose perhaps the greatest global challenge to sustainable fisheries management. The high seas account for 58 percent of the world's oceans and aren't controlled by any one country. Wild fish such as tuna and billfish are in precipitous decline in these areas, partly because of the absence of catch limits.
Closing the high seas to fishing might provide enough protection for populations to rebuild. Because they migrate, fish from protected international waters could then find their way into the exclusive economic zones (EEZs) of each nation, where they could be harvested.
“From a policy perspective, the results are incredibly important because they indicate a win-win-win — food, profit, conservation — scenario from closing the high seas,” White said.
The researchers developed a computer simulation model of global ocean fisheries that considers biological, geographic and socio-economic factors. After examining a number of management scenarios, the team found the greatest benefits in all areas from high seas closure.
“Even though our main focus was on the profitability of fisheries, this policy would represent possibly the largest conservation benefit ever enacted in the world’s ocean," said Costello. “We were pretty shocked. We definitely did not set out thinking a complete closure could be such an all-around beneficial policy."
Further research is needed before such a bold proposal could be put in practice. “We hope this can be a starting point for further analysis and debate about the ecological and economic implications and political feasibility of a high seas closure,” said White.