Global warming has forced fish stocks in the North Sea to go scores of kilometers north to cooler waters, according to a study by climate-change scientists.
Major fish species, including cod and haddock, have sought out cooler waters in response to a 1oC rise in the temperature of the North Sea over the past 25 years. In the same period, more exotic southern species have encroached on North Sea waters.
The shift in fish populations has profound implications for fisheries which have already driven stocks to record lows, the researchers say.
British scientists at the University of East Anglia and researchers at the Centre for Environment Fisheries and Aquaculture Science in Lowestoft pored over fisheries data from 1977 to 2001 and looked at the size of catches. They also examined records of sea temperatures, general climatic patterns and the effects of the Gulf Stream.
The researchers found that 21 species had shifted their distributions in line with the rise in sea temperature, and 18 species had moved much further north. According to the study, published yesterday in the journal Science, the North Sea cod population has moved 117km towards the Arctic, while haddock have moved 105km north.
The study raises concerns that some already overexploited fish stocks are under further threat from climate change.
Allison Perry, who co-authored the study, said: "We know these ecosystems are already under heavy pressure and this is an added stress. If we want to rebuild stocks we need to be more cautious because the conditions now aren't as suitable as they were 25 years ago."
"The fact that species such as haddock and cod have moved over 100km northward suggests that management programs will need to be particularly precautionary if southerly populations are to recover from overfishing," said John Reynolds, who led the study.
Many of the species studied also moved to deeper waters as they shifted north, which may also have been driven by a search for cooler waters. Populations of six species, including plaice and cuckoo rays, moved to deeper waters without changing latitude.
The findings demonstrate how sensitive fish stocks are to climate change. In 2003, scientists at the University of Texas reported that 99 species of birds, butterflies and alpine herbs had shifted 600m north each year because of global warming. In the latest study, fish populations headed north nearly four times as quickly, at an average of nearly 2.3km a year.
The shifting populations of fish have implications beyond fisheries management. The study found that smaller fish with shorter lifecycles were more likely to move north in response to climate change, with larger, slower-growing fish lagging behind. Scientists now fear that differing abilities to respond to warming waters will fragment ecosystems by separating predators from their usual prey.
‘IN A DIFFERENT PLACE’: The envoy first visited Shanghai, where he attended a Chinese basketball playoff match, and is to meet top officials in Beijing tomorrow US Secretary of State Antony Blinken yesterday arrived in China on his second visit in a year as the US ramps up pressure on its rival over its support for Russia while also seeking to manage tensions with Beijing. The US diplomat tomorrow is to meet China’s top brass in Beijing, where he is also expected to plead for restraint as Taiwan inaugurates president-elect William Lai (賴清德), and to raise US concerns on Chinese trade practices. However, Blinken is also seeking to stabilize ties, with tensions between the world’s two largest economies easing since his previous visit in June last year. At the
Nearly half of China’s major cities are suffering “moderate to severe” levels of subsidence, putting millions of people at risk of flooding, especially as sea levels rise, according to a study of nationwide satellite data released yesterday. The authors of the paper, published by the journal Science, found that 45 percent of China’s urban land was sinking faster than 3mm per year, with 16 percent at more than 10mm per year, driven not only by declining water tables, but also the sheer weight of the built environment. With China’s urban population already in excess of 900 million people, “even a small portion
UNSETTLING IMAGES: The scene took place in front of TV crews covering the Trump trial, with a CNN anchor calling it an ‘emotional and unbelievably disturbing moment’ A man who doused himself in an accelerant and set himself on fire outside the courthouse where former US president Donald Trump is on trial has died, police said yesterday. The New York City Police Department (NYPD) said the man was declared dead by staff at an area hospital. The man was in Collect Pond Park at about 1:30pm on Friday when he took out pamphlets espousing conspiracy theories, tossed them around, then doused himself in an accelerant and set himself on fire, officials and witnesses said. A large number of police officers were nearby when it happened. Some officers and bystanders rushed
Beijing is continuing to commit genocide and crimes against humanity against Uyghurs and other Muslim minorities in its western Xinjiang province, U.S. Secretary of State Antony Blinken said in a report published on Monday, ahead of his planned visit to China this week. The State Department’s annual human rights report, which documents abuses recorded all over the world during the previous calendar year, repeated language from previous years on the treatment of Muslims in Xinjiang, but the publication raises the issue ahead of delicate talks, including on the war in Ukraine and global trade, between the top U.S. diplomat and Chinese