A team of researchers using satellite feeds and common ship tracking technology found that industrial fishing covers more than 55 percent of the ocean’s surface – over four times the area covered by agriculture.
The new data set compiled is hundreds of times higher in resolution than previous global surveys and captures activities of more than 70,000 vessels, including more than 75 percent of industrial fishing vessels larger than 36 meters (118.11 feet).
“The biggest issue is a lack of transparency in the global fishing industry,” said David A. Kroodsma, director of research and development at Global Fishing Watch, the lead author of the study. “By publishing the data and analysis, we aim to increase transparency in the commercial fishing industry and improve opportunities for sustainable management,” he added. “It is amazing what we are able to see now. Previously we had a very poor understanding of where fishing was happening in the high seas.” Global Fishing Watch itself is the result of the environmental organization Oceana coming together with Google and SkyTruth several years ago to develop a tool to track large fishing vessels globally.
The study reflects the team efforts of Global Fishing Watch, the National Geographic Society’s Pristine Seas project, the University of California Santa Barbara, Dalhousie University, Sky Truth, Google and Stanford University. Their researchers processed 22 billion automatic identification system messages and tracked more than 70,000 industrial fishing vessels from 2012 through 2016, creating global dynamic footprint of fishing effort with spatial and temporal resolution two to three orders of magnitude higher than for previous data sets.
They found that global patterns of fishing have surprisingly low sensitivity to short-term economic and environmental variation and a strong response to cultural and political events such and holidays and closures, they indicated.
The data set provides greater detail than previously possibly about fishing activity on the high seas, beyond national jurisdictions. While most nations appear to fish predominantly within their own exclusive economic zones, China, Spain, Taiwan, Japan and South Korea account for 85 percent of observed fishing on the high seas.
The study showed that the total area of the ocean fished is likely higher than the 55 percent estimated, as the data do not include some fishing effort in regions of poor satellite coverage, or exclusive economic zones with a low percentage of vessels using automated information systems.
More than 37 million hours of fishing were observed in 2016 and fishing vessels traveled more than 460 million kilometers or 285,830,748 miles, a distance equivalent to going to the moon and back 600 times.
The study “Tracking the global footprint of fisheries” appears in Science, Vol. 361, Issue 6378.