Using Google Earth imagery, scientists say they’ve spotted large fishing traps in the Persian Gulf that are catching six times the amount of fish than are being reporting.
The study, the first of its kind, was done by researchers at the University of British Columbia
in Canada. Using the satellite imagery, they say the counted 1,9000 fishing weirs along the coast in 2005. The researchers say the weirs caught approximately 31,000 tons of fish, while the amount reported to the United Nation’s Food and Agriculture Organization was 5,260 tons.
Fishing weirs are traps – similar to underwater fences – that take advantage of tidal changes and currents to catch marine animals, including fish.
“This ancient fishing technique has been around for thousands of years,” says Dalal Al-Abdulrazzak, a PhD student with the UBC Fisheries Centre’s Sea Around Us Project and the study’s lead author. “But we haven’t been able to truly grasp their impact on our marine resources until now, with the help of modern technology.”
The study shows the potential for using remote-sensing approaches, such as satellite imagery, to validate catch statistics and fisheries operations in general.
“Time and again we’ve seen that global fisheries catch data don’t add up,” says Daniel Pauly, principal investigator with the Sea Around Us Project and the study’s co-author. “Because countries don’t provide reliable information on their fisheries’ catches, we need to expand our thinking and look at other sources of information and new technologies to tell us about what’s happening in our oceans.”