Fish 'shrinking due to global warming'

[Jimmy_041]

Now I am worried about the effects of global warming............

FISH have lost half their average body mass and smaller species are making up a larger proportion of European fish stocks as a result of global warming, a study has found.

”It's huge,” said study author Martin Daufresne of the Cemagref Public Agricultural and Environmental Research Institute in Lyon, France.

”Size is a fundamental characteristic that is linked to a number of biological functions, such as fecundity – the capacity to reproduce.”

Smaller fish tend to produce fewer eggs. They also provide less sustenance for predators – including humans – which could have significant implications for the food chain and ecosystem.

A similar shrinking effect was recently documented in Scottish sheep and Mr Daufresne said it is possible that global warming could have “a significant impact on organisms in general.”

Earlier research has already established that fish have shifted their geographic ranges and their migratory and breeding patters in response to rising water temperatures. It has also been established that warmer regions tend to be inhabited by smaller fish.

Mr Daufresne and his colleagues examined long-term surveys of fish populations in rivers, streams and the Baltic and North Seas and also performed experiments on bacteria and plankton.

They found the individual species lost an average of 50 per cent of their body mass over the past 20 to 30 years while the average size of the overall fishing stock had shrunk by 60 per cent.

This was a result of a decrease in the average size-at-age and an increase in the proportion of juveniles and small-sized species, Daufresne said.

”It was an effect that we observed in a number of organisms and in a number of very different environments – on fish, on plankton, on bacteria, in fresh water, in salt water - and we observed a global shrinking of size for all the organisms in all the environments,” Mr Daufresne said.

While commercial and recreational fishing did impact some of the fisheries studied, it “cannot be considered as the unique trigger” for the changes in size, the study published in the Proceedings of the National Academy of Sciences found.

”Although not negating the role of other factors, our study provides strong evidence that temperature actually plays a major role in driving changes in the size structure of populations and communities,” the study concluded.

[Mickyj]

No wonder I'm having trouble catching some

[Jimmy_041]

I'm going to have to reduce the size of the hooks in my fishing box

[spell_check]

Over-fishing (i.e. commercial) wouldn't have anything to do with it?

[JAS]

Over-fishing (i.e. commercial) wouldn't have anything to do with it?

...and the French wouldn't know anything about that now would they???

Now why do I suspect that EU fishing quota's might be up for review or something soon.

Regards
JAS

[Jimmy_041]

Over-fishing (i.e. commercial) wouldn't have anything to do with it?

...and the French wouldn't know anything about that now would they???

Regards
JAS

and the Spaniards..........

[Leaping Lindner]

Global warming is a myth. Just ask Steven Fielding. If anyone would know about myths it's him

[Jimmy_041]

I am beginning to believe it though - I can tell by the size of fish I am catching thse days

[Psyber]

Global warming is a myth. Just ask Steven Fielding. If anyone would know about myths it's him

I don't think global warming is a myth, but I'm not convinced it isn't just part of the natural cycle of sun activity. The planet has been warmer in the past than it is now.
However, I am not suggesting we shouldn't do anything about our pollution output - we definitely should.
Fine particulates that can penetrate cells may injure our health, and there are recent suggestions that fine particulates from laser printers may be a major factor in "sick building syndrome".
What really concerns me is the presence of powerful cancer causing agents in diesel exhousts - including those running bio-diesel...

[Leaping Lindner]

Guys I had my tongue firmly in my cheek. I find it strange that Steven Fielding despite scientific evidence doesn't believe global warming yet he doesn't have a problem unconditionally accepting as fact fairy tales written 2000 years ago. Seems odd to me.

[MightyEagles]

Over-fishing (i.e. commercial) wouldn't have anything to do with it?

...and the French wouldn't know anything about that now would they???

Regards
JAS

and the Spaniards..........

and the Japanese.

[Jimmy_041]

Over-fishing (i.e. commercial) wouldn't have anything to do with it?

...and the French wouldn't know anything about that now would they???

Regards
JAS

and the Spaniards..........

and the Japanese.

and the Chinese

[therisingblues]

Global warming is a myth. Just ask Steven Fielding. If anyone would know about myths it's him

I don't think global warming is a myth, but I'm not convinced it isn't just part of the natural cycle of sun activity. The planet has been warmer in the past than it is now.
However, I am not suggesting we shouldn't do anything about our pollution output - we definitely should.
Fine particulates that can penetrate cells may injure our health, and there are recent suggestions that fine particulates from laser printers may be a major factor in "sick building syndrome".
What really concerns me is the presence of powerful cancer causing agents in diesel exhousts - including those running bio-diesel...

What is happening now was predicted over 50 years ago when they discovered the level of CO2 in the atmosphere was increasing, along with human output of the same gas. As time has gone by they have uncovered more and more facts to back up their theories.
How anybody today could possibly say that what is happening is natural, after all the warnings and reasoning we received in advance completely bamboozles me.

P.S Yes I also thought Lindner's original post was tongue in cheek.

[Psyber]

Yes, I also understood. I was commenting on Fielding's views, not thinking they were LL's.

TRB, I'm amazed that anyone can swallow whole the idea that all the changes are man induced, and new, when the Romains were growing grapes in the region of Yorkshire around 200AD, and Greenland was green in the period around 850 to 1100 AD. Mind you, I have heard climate catastrophists argue that Erik the Red was the first real estate scammer and it was always really Whiteland!

Here is some alternative reading from the "dark side":
http://www.skepticalscience.com/
http://scienceandpublicpolicy.org/sppi_ ... ation.html

And for a more neutral look:
Look at the cycles on the long term temperature chart based on ice core studies in this one:
http://en.wikipedia.org/wiki/Ice_core

These are interesting too:
http://en.wikipedia.org/wiki/Maunder_minimum
http://www.solarstorms.org/CloudCover.html

I'm just arguing for a balanced examination of the issue, while supporting the idea that we clean up our act anyway because regardless of whether or not we are generating a non-cyclical and potentially catastrophic change, we are doing damage in many ways - like the cancer causing agents in diesel fumes, and the excess near microwave frequency radiation in our modern environment.
http://www.cnet.com.au/mobile-phones-wo ... 287841.htm

[Mickyj]

I'm going to have to reduce the size of the hooks in my fishing box

I am already using size 16 trout hooks jimmy I cant go any smaller

[therisingblues]

Yes, I also understood. I was commenting on Fielding's views, not thinking they were LL's.

TRB, I'm amazed that anyone can swallow whole the idea that all the changes are man induced, and new, when the Romains were growing grapes in the region of Yorkshire around 200AD, and Greenland was green in the period around 850 to 1100 AD. Mind you, I have heard climate catastrophists argue that Erik the Red was the first real estate scammer and it was always really Whiteland!

Here is some alternative reading from the "dark side":
http://www.skepticalscience.com/
http://scienceandpublicpolicy.org/sppi_ ... ation.html

And for a more neutral look:
Look at the cycles on the long term temperature chart based on ice core studies in this one:
http://en.wikipedia.org/wiki/Ice_core

These are interesting too:
http://en.wikipedia.org/wiki/Maunder_minimum
http://www.solarstorms.org/CloudCover.html

I'm just arguing for a balanced examination of the issue, while supporting the idea that we clean up our act anyway because regardless of whether or not we are generating a non-cyclical and potentially catastrophic change, we are doing damage in many ways - like the cancer causing agents in diesel fumes, and the excess near microwave frequency radiation in our modern environment.
http://www.cnet.com.au/mobile-phones-wo ... 287841.htm

I'll get around to reading those links one day Psyber. A bit too busy at the moment. But to date I haven't read anything close to convincing that the rise in temperatures is solely the hand of mother nature. Which is my particular beef.
A few years back it was difficult convincing some people that global warming was actually occurring. Now those same people tend to cast aside any responsibility by the human race in the global warming phenomenon. I think that it is more comforting for some people to believe that the environment's destruction lays outside the human sphere of influence, while others just refuse to acknowledge man's role because it is uneconomically viable. I think naturally I'd belong to the first group but having seen what evidence I have there's no way I could maintain that view.
Nature may or may not play some part in global warming. I sort of wish it was all nature, because nature has a way of fixing things, then we could go on enjoying our oil driven luxuries guilt free. I do think that most of the changes are man induced, remove our negative influences and the whole problem would be a whole lot more bearable IMO. But I am not so stubborn as to ignore or refuse to listen to another's ideas and when I get a chance to read those links I might post again on the topic.

[Psyber]

Global warming is a proven fact.
In about a billion years all the water on earth will boil away.
This was an interesting aside on this video, which itself is an interesting examination of world energy provision that puts up the most convincing case for solar power use that I have seen.
It has changed my mind about nuclear energy: http://www.adelaide.edu.au/researchtues ... video.html

There is lots of other interesting stuff here: http://www.adelaide.edu.au/researchtuesdays/

[Psyber]

However, here is a counter argument in favour of nuclear technology - also from Adelaide University..
http://www.abc.net.au/rn/scienceshow/st ... 629053.htm

[dedja]

Global warming is a proven fact.

Unless you're Andrew Bolt or Steve Fielding ...

[Psyber]

Global warming is a proven fact.

Unless you're Andrew Bolt or Steve Fielding ...

I should perhaps have said - "In about a billion years all the water on earth will boil away, purely due to the expansion of the sun".
I'm not convinced about anthropogenic warming, as distinct from solar effects and natural cycles..

My recent reading of a book entitled "A History of the Vikings", revealed that most of the colonisation of Iceland, Greenland, and northen America, ocurred during the 10th century AD - earlier than I had thought - and that a major cooling cycle followed so that most of the colonies collapsed by the early 12th century.

Confirming reports come from the history of the Thames freezing.
It appears we are now recovering from a period of "Global Cooling" extending from about 1100 AD to the early 19th century.

From 1400 into the 19th century, there were 24 winters in which the Thames was recorded to have frozen over at London; if "more or less frozen over" years (in parentheses) are included, the number is 26: 1408, 1435, 1506, 1514, 1537, 1565, 1595, 1608, 1621, 1635, 1649, 1655, 1663, 1666, 1677, 1684, 1695, 1709, 1716, 1740, (1768), 1776, (1785), 1788, 1795, and 1814.

http://en.wikipedia.org/wiki/River_Thames_frost_fairs

The Thames has been frozen over 40 times since 1142 and doubtless countless times before that, although the many narrow piers on the older bridges may have aided freezing as far downstream as London and within the tidal reaches (Teddington, well west of old London, is the tidal head of the river). A recent account of the freezings over is Helen Humphreys, “The Frozen Thames”, 2007, McLelland & Stewart, Toronto, which bases itself on historical accounts related to each of the events.

http://web.mac.com/keithjtinkler/Weathe ... hames.html