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Re-hashing a 25 year old theory on how Salmon might find their way back to their Scottish birthplace
The Scotsman, Tall and Handsome Built ^ | December 2, 2008 | Ben Bailey

Posted on 01/19/2013 7:56:55 PM PST by SunkenCiv

Every year, 20 million of them leave Scottish rivers and travel thousands of miles to Norway and Greenland to feed. Remarkably, they then return to Scotland, often to within 100 metres of where they were hatched, in a process that can take more than two years.

How salmon complete such voyages across sea and ocean without getting lost has baffled scientists for generations. But a new theory proposes that the fish use the earth's magnetic field to locate their origins in Scottish rivers.

Scientists believe that, in a process called "natal honing", salmon imprint the magnetic signature of their home once reaching adulthood...

The Earth's magnetic field varies across the globe – each oceanic region has a different magnetic signature. Researchers believe that by remembering the unique "magnetic address" of their birthplace, fish may be able to distinguish that location from all others.

Salmon and sea turtles often bypass suitable breeding grounds on their vast journeys in favour of the places they were born. Scientists believe the fish do this due to previous breeding success at a particular site...

Scientists agree the Earth's magnetic field changes over time and probably helps animals arrive only in the general area of their birthplace. Then, once an animal is close to their target, other senses, such as vision or smell, may be used. Salmon are known to use their sense of smell to locate spawning grounds once they are close.

(Excerpt) Read more at martinfrost.ws ...


TOPICS: History; Science; Travel
KEYWORDS: catastrophism; godsgravesglyphs; salmon; scotlandyet

Full title: "Re-hashing a 25 year old theory on how Salmon might find their way back to their Scottish birthplace".
Re-hashing a 25 year old theory on how Salmon might find their way back to their Scottish birthplace

1 posted on 01/19/2013 7:57:06 PM PST by SunkenCiv
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Do Salmon Navigate by the Earth’s Magnetic Field?
Alaska Science Forum
Article #691
by Larry Gedney
November 23, 1984
http://www2.gi.alaska.edu/ScienceForum/ASF6/691.html


2 posted on 01/19/2013 8:02:37 PM PST by SunkenCiv (Romney would have been worse, if you're a dumb ass.)
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Magnetic north pole shift: NASA and Egyptians say this has happened before
http://www.examiner.com/article/magnetic-north-pole-shift-nasa-and-egyptians-say-this-has-happened-before


3 posted on 01/19/2013 8:03:26 PM PST by SunkenCiv (Romney would have been worse, if you're a dumb ass.)
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To: 75thOVI; agrace; aimhigh; Alice in Wonderland; AndrewC; aragorn; aristotleman; Avoiding_Sulla; ...



4 posted on 01/19/2013 8:03:31 PM PST by SunkenCiv (Romney would have been worse, if you're a dumb ass.)
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Bacteria which sense the Earth’s magnetic field (”Simple” organisms?)
EurekAlert! | November 20, 2005 | Staff
Posted on 11/22/2005 2:15:15 PM PST by DaveLoneRanger
http://www.freerepublic.com/focus/news/1526963/posts


5 posted on 01/19/2013 8:05:06 PM PST by SunkenCiv (Romney would have been worse, if you're a dumb ass.)
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 GGG managers are SunkenCiv, StayAt HomeMother & Ernest_at_the_Beach
Just adding to the catalog, not sending a general distribution.

To all -- please ping me to other topics which are appropriate for the GGG list.


6 posted on 01/19/2013 8:05:06 PM PST by SunkenCiv (Romney would have been worse, if you're a dumb ass.)
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To: SunkenCiv

Wonder what it is that Leeds them back.


7 posted on 01/19/2013 8:14:27 PM PST by Ken H
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To: Ken H

Haggis we’ll never know for sure.


8 posted on 01/19/2013 8:20:58 PM PST by SunkenCiv (Haggis? Really? Again? So soon?)
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To: SunkenCiv
Every year, 20 million of them leave Scottish rivers and travel thousands of miles to Norway and Greenland to feed.

I think the bigger puzzle is how do they find there way to Norway and Greenland?

They can be imprinted on their journey with the route they took but they have never been to the feeding grounds before.

9 posted on 01/19/2013 9:39:58 PM PST by Pontiac (The welfare state must fail because it is contrary to human nature and diminishes the human spirit.)
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To: SunkenCiv

On a trip to Scotland last year my party walked across a bridge and observed salmon going/jumping back up a river. Don’t ask me what river.


10 posted on 01/20/2013 3:40:19 AM PST by driftless2
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To: SunkenCiv

FYI, PBS is currently running a superb series on volcanoes. A recent episode dealt with how certain Alaskan salmon adapted some 2000 y ears ago, when a volcano erupted and completely blocked their access to the rivers and streams where they spawned. They were somehow, immediately able to modify their behavior. The episode should be on the PBS website.


11 posted on 01/20/2013 5:16:40 AM PST by ken5050 ("One useless man is a shame, two are a law firm, three or more are a Congress".. John Adams)
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To: SunkenCiv
Haggis we’ll never know for sure.

The Royal Mail?


12 posted on 01/20/2013 5:21:42 AM PST by COBOL2Java (Fighting Obama without Boehner & McConnell is like going deer hunting without your accordion)
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To: Pontiac
“the bigger puzzle is how do they find there way to Norway and Greenland? “

I have thought about the salmon's journey for years without arriving at your now-obvious question. Nice work.

A corollary of your question is “Why do hatchery raised salmon mingle with returning wild salmon since the hatchers have never experienced the birth stream of the wilds?”

13 posted on 01/20/2013 5:28:06 AM PST by Makana
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To: Makana

Monarch butterfly migrations are also a wonder. Several generations are involved with the total trip.


14 posted on 01/20/2013 5:59:16 AM PST by Gadsden1st
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To: SunkenCiv

GPS


15 posted on 01/20/2013 6:02:16 AM PST by SWAMPSNIPER (The Second Amendment, a Matter of Fact, Not a Matter of Opinion)
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To: SunkenCiv

A sixth sense that humans have lost or never needed


16 posted on 01/20/2013 7:00:17 AM PST by winodog (Thank you Jesus for the calm in my life)
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To: winodog

I’m irresistably attracted to the smell of pizza... :’)


17 posted on 01/21/2013 6:50:18 AM PST by SunkenCiv (Romney would have been worse, if you're a dumb ass.)
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To: driftless2

What river?


18 posted on 01/21/2013 8:11:00 AM PST by SunkenCiv (Romney would have been worse, if you're a dumb ass.)
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To: Pontiac; SWAMPSNIPER; driftless2

Thanks ken5050!


19 posted on 01/21/2013 8:11:46 AM PST by SunkenCiv (Romney would have been worse, if you're a dumb ass.)
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To: ken5050; SWAMPSNIPER; driftless2

Thanks Pontiac.


20 posted on 01/21/2013 8:11:46 AM PST by SunkenCiv (Romney would have been worse, if you're a dumb ass.)
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To: SunkenCiv

Some river around Banchory. Where one of my wife’s sisters lives.


21 posted on 01/21/2013 9:26:10 AM PST by driftless2
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To: ken5050
certain Alaskan salmon adapted some 2000 y ears ago, when a volcano erupted and completely blocked their access to the rivers and streams where they spawned.

Don’t tell the environmentalist or the EPA. They would have a meltdown.

If that is true we could start building Hydroelectric Dams again.

22 posted on 01/21/2013 5:05:02 PM PST by Pontiac (The welfare state must fail because it is contrary to human nature and diminishes the human spirit.)
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To: SunkenCiv
Maybe these guys can give us the answer:


23 posted on 01/25/2013 3:24:16 PM PST by colorado tanker
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To: Pontiac; driftless2

I would strongly suggest the movie “Salmon Fishing in The Yemen”.

Very funny !


24 posted on 01/25/2013 3:29:57 PM PST by Mears
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