Little room left for fisheries
The Earth has run out of room to expand fisheries, according to a new study led by University of British Columbia researchers that charts the systemic expansion of industrialized fisheries.
The Earth has run out of room to expand fisheries, according to a new study led by University of British Columbia researchers that charts the systematic expansion of industrialized fisheries.
In collaboration with the National Geographic Society and published today in the online journal PLoS ONE, the study is the first to measure the spatial expansion of global fisheries. It reveals that fisheries expanded at a rate of one million sq. kilometres per year from the 1950s to the end of the 1970s. The rate of expansion more than tripled in the 1980s and early 1990s 鈥� to roughly the size of Brazil鈥檚 Amazon rain forest every year.
Between 1950 and 2005, the spatial expansion of fisheries started from the coastal waters off the North Atlantic and Northwest Pacific, reached into the high seas and southward into the Southern Hemisphere at a rate of almost one degree latitude per year. It was accompanied by a nearly five-fold increase in catch, from 19 million tonnes in 1950, to a peak of 90 million tonnes in the late 1980s, and dropping to 87 million tonnes in 2005, according to the study.
鈥淭he decline of spatial expansion since the mid-1990s is not a reflection of successful conservation efforts but rather an indication that we鈥檝e simply run out of room to expand fisheries,鈥� says Wilf Swartz, a PhD student at UBC Fisheries Centre and lead author of the study.
Meanwhile, less than 0.1 per cent of the world鈥檚 oceans are designated as marine reserves that are closed to fishing.
鈥淚f people in Japan, Europe, and North America find themselves wondering how the markets are still filled with seafood, it鈥檚 in part because spatial expansion and trade makes up for overfishing and 鈥榝ishing down the food chain鈥� in local waters,鈥� says Swartz.
鈥淲hile many people still view fisheries as a romantic, localized activity pursued by rugged individuals, the reality is that for decades now, numerous fisheries are corporate operations that take a mostly no-fish-left-behind approach to our oceans until there鈥檚 nowhere left to go,鈥� says Daniel Pauly, co-author and principal investigator of the Sea Around Us Project at UBC Fisheries Centre.
The researchers used a newly created measurement for the ecological footprint of fisheries that allows them to determine the combined impact of all marine fisheries and their rate of expansion. Known as SeafoodPrint, it quantifies the amount of 鈥減rimary production鈥� 鈥� the microscopic organisms and plants at the bottom of the marine food chain 鈥� required to produce any given amount of fish.
鈥淭his method allows us to truly gauge the impact of catching all types of fish, from large predators such as bluefin tuna to small fish such as sardines and anchovies,鈥� says Pauly. 鈥淏ecause not all fish are created equal and neither is their impact on the sustainability of our ocean.鈥�
鈥淭he era of great expansion has come to an end, and maintaining the current supply of wild fish sustainably is not possible,鈥� says co-author and National Geographic Ocean Fellow Enric Sala. 鈥淭he sooner we come to grips with it 鈥� similar to how society has recognized the effects of climate change 鈥� the sooner we can stop the downward spiral by creating stricter fisheries regulations and more marine reserves.鈥�
More information: View the study at .
Provided by University of British Columbia
