HMAP Dataset 17: North Sea Demersal Fish

Fishery scientists tend to take a rather short-term view of history (Pauly 1995), referring only as far back in time as their biological sampling programmes will allow. Most fishery- independent survey time series do not extend back beyond the 1970s, yet we are increasingly being asked to comment on the longer-term impacts of climate change or increased fishing pressure. A recent study (Myers & Worm 2003) demonstrated that populations of predatory fishes can decline by as much as 80 percent within the first 10-15 years of exploitation, and that the majority of fish stocks in the ocean today are at 10 percent or less of virgin levels. This implies that the most dramatic changes in exploited fish populations can occur long before scientifically rigorous monitoring systems are in place. Clearly, fisheries scientists must begin to take a longer-term view if they are ever to untangle natural and anthropogenic influences on marine systems.