British Fisheries Declined Earlier, More Heavily, Than Previously Believed
Modern fishing vessels in the United Kingdom work 17 times harder than their Victorian counterparts to catch the same amount of fish, according to a recent study by British researchers. Writing in the journal Nature Communications, Ruth Thurstan of the University of York and colleagues state that their findings show that groundfish populations in the region have been declining for far longer, and have deteriorated more significantly, than had previously been believed, reports www.megafishnet.com with reference to SeaWeb.
Examining government records dating back to the late 19th century, researchers calculated the "landings of fish per unit of fishing power" (LPUP) by comparing the fishing effort of trawling vessels with the amount they caught. From 1889 to 2007, the LPUP declined 500 times for halibut, more than 100 times for haddock and more than 20 times for plaice, wolffish, hake and ling.
In 1889, write the authors, "a largely sail-powered fleet landed twice as many fish into the United Kingdom than the present-day fleet of technologically sophisticated vessels." By 1910, as an expanding fleet of steam trawlers began to dominate, landings were four times higher than today. At the fishery's peak in 1938, landings were 5.4 times higher. Thereafter, catches began to decline, but for decades, say the study's authors, the full extent of the decrease in groundfish numbers has been partially masked by the increased efficiency of the fishing fleet.
Thurstan and colleagues say their findings have particular significance for management of fisheries, given that European fish stock assessments and the management decisions based on them rely on data that stretches back only between 20 and 40 years-by which time, the new study shows, fish populations were already a fraction of their initial size. In fact, they point out, although catch statistics date from 1889, there is some evidence that trawlers had affected fish populations and catches before then: Concerns about the state of some nearshore fish stocks prompted the establishment of a Royal Commission of Enquiry into fisheries as early as 1863.