Time series of areas newly exploited by marine fisheries (1950–2005), expressed in km2. Newly exploited areas defined as regions where primary production required (PPR) to sustain reported fisheries landings exceeds the threshold percentage of local primary production (PP). Results based on three exploitation thresholds (10%, 20% and 30%) are presented. Swartz, et al., 2010

By Allan Dowd; editing by Peter Galloway
Thu Dec 2, 2010 5:50pm EST VANCOUVER (Reuters) – The world’s fishing industry is fast running out of new ocean fishing grounds to exploit as it depletes existing areas through unsustainable harvesting practices, according to a study published Thursday. Expansion into unexploited fishing grounds allowed global catches to increase for decades, and disguised the fact that older areas were being depleted, according researchers at the University of British Columbia and National Geographic. “We knew the expansion was going on, but this is the first time we have quantified it,” said Daniel Pauly, a scientist at the Vancouver-based university who co-authored the report published in the online journal PLoS ONE. (here) About 19 million tons of fish were landed in 1950, and that increased to a peak of 90 million tons a year in the late 1980s, according to the researchers, who looked at data from 1950 to 2005. The researchers tracked the expansion of fishing activity using computer models that examine both the total number of fish caught and the impact that catching different types of fish has had on the ocean’s productivity. By the late 1990s, the world’s fishing fleets had largely run out of new fishing grounds to exploit, the researchers said. … That expansion has left only unproductive fishing areas on the high seas and the ice-covered waters of the Arctic and Antarctic for boats to move into. Some other researchers have complained that recent studies warning the oceans are being depleted of larger fish are making the situation appear worse than it really is. Pauly said those critics have ignored the role that the move of the fleet into new fishing grounds has on fish-catch data, which is documented in the current study.

World running out of new places to fish: study