Climate change threatens to SHRINK FISH AND CHIP SUPPERS
Teeny oxygen-starved cod will hit global food supplies
Climate change could threaten the quintessential British meal, the venerable fish and chips, which will only be available in small portions or not at all if boffins are correct.
The scientists have warned that the body weight of fish, including North Sea haddock and cod, will drop if oceans warm up. The theory goes that warmer waters increases the metabolic rate in fish, which will increase the demand for oxygen. If there isn't enough oxygen to go around, then the fish body weight will drop, it is believed.
According to computer models, the maximum body weight for more than 600 species could shrink by 14 to 20 per cent between the years 2000 and 2050.
“We were surprised to see such a large decrease in fish size,” study lead author William Cheung, an assistant professor at the University of British Columbia Fisheries Centre, said.
“Marine fish are generally known to respond to climate change through changing distribution and seasonality. But the unexpectedly big effect that climate change could have on body size suggests that we may be missing a big piece of the puzzle of understanding climate change effects in the ocean.”
The researchers already know that the number of fish in the world's oceans is likely to decline with climate change, but the study shows that the ones that are left will still get smaller.
The fishes' growth is linked to their oxygen supply, an idea another UBC boffin, Daniel Pauly, first suggested thirty years ago. But this is the first time his idea has been applied to the global fish population.
“It’s a constant challenge for fish to get enough oxygen from water to grow, and the situation gets worse as fish get bigger,” Pauly, who also worked on this study, said.
“A warmer and less-oxygenated ocean, as predicted under climate change, would make it more difficult for bigger fish to get enough oxygen, which means they will stop growing sooner.”
The biggest effects of fish shrinking are likely to be seen in the tropics, but colder seas will also see the migration of those tropical fish as they warm, another factor impacting the size of fish in those waters.
The study was published in Nature Climate Change. ®
There is of course no connection to the depletion of the fish stocks due to over-fishing, there's no need to control for that particular factor.
Cod are already shrinking due to natural selection.
The nets used to trawl for cod have to have holes large enough to let the young cod escape. As a result, if you are an older smaller cod you are more likely to survive and pass your genes on. Hence you get shrinking fish.
There is a whole host of research out their about fish, including changes is size, all based upon actual physical evidence and not some computer model being tweaked by a researcher, who has probably never even handled a fish let alone measured it.
What you've displayed is the clear position of someone who doesn't understand science and/or the scientific method.
If you did, then you would know that no scientist will ever say "if x happens, then y *will* happen", they may, in some of the more stable and accepted scientific answers (say, for example, Boyles Law), say that "if x happens, then we expect to see y".
The reason for this is that science doesn't work with absolutes, it works with probabilities and with any probability you have to accept that even at a tiny level, you could be wrong (this is why it's still called the Theory of Evolution).
If you want to talk in absolute's, talk to a politician, religious fanatic or a sales-man.