Fishing vessels differ in fishing power-that is, in the quantity of fish they would catch per unit time if they were fishing at the same time and location-and there is a general trend of increasing fishing power over time. Typically, fishing power studies are limited to comparisons over 1-2 decades, but here I attempt to quantify this trend for English North Sea trawlers over the past 120 years. A review of fishing history shows how sailing trawlers, steam trawlers, and currently both motor otter trawlers and twin-beam trawlers have in turn dominated the trawl fisheries. A huge, overall increase in fishing power has occurred but the trend has been all but linear: fishing power has sometimes "leapt" forward within a few years, but at times has also stagnated for decades. Compared with historical sailing trawlers, motor otter trawlers around the Millennium are estimated to have 50 times higher cod fishing power, and twin-beam trawlers to have 100 times higher plaice fishing power. However, this does not mean that fisheries have become more profitable, because increases in catch rates have lagged far behind those in fishing power, and everything points in the direction of great overcapacity of the current international North Sea trawling fleet.
|Title of host publication||Advances in Fisheries Science: 50 years on from Beverton and Holt|
|Number of pages||25|
|Publication status||Published - 9 Feb 2009|