Using satellite imagery from Google Earth, UBC researchers estimated that there were 1,900 fishing weirs along the coast of the Persian Gulf during 2005 and that they caught approximately 31,000 tonnes of fish that year. The official number reported by the seven countries in the region to the United Nation\u2019s Food and Agriculture Organization was 5,260 tonnes.<\/p>\n
Fishing weirs are semi-permanent traps that take advantage of tidal differences to catch a wide variety of marine species. Used in Southeast Asia, Africa and parts of North America, some weirs can be more than 100m long.<\/p>\n
\u201cThis ancient fishing technique has been around for thousands of years,\u201d says Dalal Al-Abdulrazzak, a PhD student with the UBC Fisheries Centre\u2019s Sea Around Us<\/i> Project and the study\u2019s lead author. \u201cBut we haven\u2019t been able to truly grasp their impact on our marine resources until now, with the help of modern technology.\u201d<\/p>\n
The study shows the potential for using remote-sensing approaches, such as satellite imagery, to validate catch statistics and fisheries operations in general.<\/p>\n
\u201cTime and again we\u2019ve seen that global fisheries catch data don\u2019t add up,\u201d says Daniel Pauly, principal investigator with the Sea Around Us<\/i> Project and the study\u2019s co-author. \u201cBecause countries don\u2019t provide reliable information on their fisheries\u2019 catches, we need to expand our thinking and look at other sources of information and new technologies to tell us about what\u2019s happening in our oceans.\u201d<\/p>\n