Fishy fishers' fishing figures fingered using Google Earth Gulf pics
Grad student claims thousands more tonnes caught than reported
A scientist has used Google Earth to uncover a Middle Eastern fish scam which could mean that six times more sea dwellers are caught than is officially reported.
Dalal Al-Abdulrazzak wanted to suss out whether fishermen in the Persian Gulf were telling the truth about how many fish they landed.
She carried out the "first example of fisheries catch estimates from space," using the advertising giant's services to look at the coastlines of six countries. After close examination, the oceanic expert spotted 1,900 fish traps, weir-like constructions which have been used for more than 3,000 years.
These trap numbers led her to calculate that the local fishermen could be netting up to 34,000 tonnes of fish every year, much more than the official reported number of 5,908 tonnes in total for the six countries.
Official estimates claim that just 1 percent of the total catch come from these aquatic killing fields.
But Al-Abdulrazzak, a graduate student in fisheries science at the University of British Columbia in Vancouver, Canada, rubbished the this figure.
"My estimate says it is closer to 10 percent," Al-Abdulrazzak said. "So, it is a lot more significant than they are giving these traps credit for."
She analysed Google Maps images from 2005, which were the last decent shots of the Persian Gulf at low tide, counting some 1,656 fish traps, which she then bumped up to 1,900 to make up for gaps in coverage and areas which were only pictured in low resolution.
After oil, fisheries are the second most important resource in the Gulf. The scrabble for cash could "could have dire consequences for fisheries stock in the long term", Al-Abdulrazzak warned.
Weirs have been used in the area for three millenia. Fish swim into them at high tide and bump into a wall, before instinctively swimming in the direction of the deep sea. However, instead of paddling to freedom, they end up stuck in an enclosure.
"Once they are in there and the tide starts receding, they are stuck. At low tide, the fishermen can just walk out and start collecting the fish," Al-Abdulrazzak continued.
The traps are particularly dangerous to young fish who have yet to spawn, as they prefer to swim in shallow waters around the coastline.
The research is called Managing fisheries from space: Google Earth improves estimates of distant fish catches and is published in the ICES Journal of Marine Science. ®