We
all know the story. Sockeye Salmon migrate over incredible distances
from the rivers out into the oceans. Years after their first migration,
the salmon swim back upstream to their birthplace to spawn their young.
But how do they find their way around such vast distances?
A new study sheds some light on the matter. It suggests that the salmon are able to locate the spawning grounds by sensing the
magnetic signature of the river in which they were born. The Earth has a
magnetic field that is strongest at the poles and weakest at the
equator. There are fluctuations in the intensity of this magnetic field
at any locations from year to year. After analysing 56 years of data
(which identified the routes taken by the salmon from the ocean to the
rivers), the researchers realized that the intensity of the magnetic
field could be used to predict the route taken by the salmon around
Vancouver Island.
It was shown that every year, the salmon
could be expected to take the route that had a magnetic signature most
similar to that of the Fraser River when the salmon initially migrated
to the Pacific Ocean. The findings strongly suggest that juvenile salmon
are able to learn and remember the magnetic signature of their spawning
ground. By remembering this, they are able to use the memory as a sort
of in-built GPS to find their way back.
It is common knowledge
that some animals are able to use the Earth’s magnetic field as a
compass to orient themselves to a straight route. However, this is the
first instance of an animal learning and remembering magnetic signature
in such a way. This makes the discovery an extremely important one in
the field of behavioural biology. Furthermore, using this knowledge, it
may be possible to predict the future movement of salmon during their
migrations which is useful for fisheries management.
There is
still much to learn about the salmon behaviour. For example, we still
don’t know “exactly how early and how often the salmon check Earth’s
magnetic field” on the way back home. However, one of the researchers
thinks that considering how long the journey is (up to 4000 miles), the
migratory choice would probably be made pretty early. So for the initial
orientation, they might use the Earth’s magnetic field to aid them.
Once they get close to the coastline, they might check the magnetic
field more regularly to get closer to their destination. Once the salmon
reach their home river, they might use their sense of smell to help
them find the specific tributary in which they were born.
Read all about it: http://bit.ly/W0vq7c
Image source: http://bit.ly/WOO2Hm
We
all know the story. Sockeye Salmon migrate over incredible distances
from the rivers out into the oceans. Years after their first migration,
the salmon swim back upstream to their birthplace to spawn their young.
But how do they find their way around such vast distances?
A new study sheds some light on the matter. It suggests that the salmon are able to locate the spawning grounds by sensing the magnetic signature of the river in which they were born. The Earth has a magnetic field that is strongest at the poles and weakest at the equator. There are fluctuations in the intensity of this magnetic field at any locations from year to year. After analysing 56 years of data (which identified the routes taken by the salmon from the ocean to the rivers), the researchers realized that the intensity of the magnetic field could be used to predict the route taken by the salmon around Vancouver Island.
It was shown that every year, the salmon could be expected to take the route that had a magnetic signature most similar to that of the Fraser River when the salmon initially migrated to the Pacific Ocean. The findings strongly suggest that juvenile salmon are able to learn and remember the magnetic signature of their spawning ground. By remembering this, they are able to use the memory as a sort of in-built GPS to find their way back.
It is common knowledge that some animals are able to use the Earth’s magnetic field as a compass to orient themselves to a straight route. However, this is the first instance of an animal learning and remembering magnetic signature in such a way. This makes the discovery an extremely important one in the field of behavioural biology. Furthermore, using this knowledge, it may be possible to predict the future movement of salmon during their migrations which is useful for fisheries management.
There is still much to learn about the salmon behaviour. For example, we still don’t know “exactly how early and how often the salmon check Earth’s magnetic field” on the way back home. However, one of the researchers thinks that considering how long the journey is (up to 4000 miles), the migratory choice would probably be made pretty early. So for the initial orientation, they might use the Earth’s magnetic field to aid them. Once they get close to the coastline, they might check the magnetic field more regularly to get closer to their destination. Once the salmon reach their home river, they might use their sense of smell to help them find the specific tributary in which they were born.
Read all about it: http://bit.ly/W0vq7c
Image source: http://bit.ly/WOO2Hm
A new study sheds some light on the matter. It suggests that the salmon are able to locate the spawning grounds by sensing the magnetic signature of the river in which they were born. The Earth has a magnetic field that is strongest at the poles and weakest at the equator. There are fluctuations in the intensity of this magnetic field at any locations from year to year. After analysing 56 years of data (which identified the routes taken by the salmon from the ocean to the rivers), the researchers realized that the intensity of the magnetic field could be used to predict the route taken by the salmon around Vancouver Island.
It was shown that every year, the salmon could be expected to take the route that had a magnetic signature most similar to that of the Fraser River when the salmon initially migrated to the Pacific Ocean. The findings strongly suggest that juvenile salmon are able to learn and remember the magnetic signature of their spawning ground. By remembering this, they are able to use the memory as a sort of in-built GPS to find their way back.
It is common knowledge that some animals are able to use the Earth’s magnetic field as a compass to orient themselves to a straight route. However, this is the first instance of an animal learning and remembering magnetic signature in such a way. This makes the discovery an extremely important one in the field of behavioural biology. Furthermore, using this knowledge, it may be possible to predict the future movement of salmon during their migrations which is useful for fisheries management.
There is still much to learn about the salmon behaviour. For example, we still don’t know “exactly how early and how often the salmon check Earth’s magnetic field” on the way back home. However, one of the researchers thinks that considering how long the journey is (up to 4000 miles), the migratory choice would probably be made pretty early. So for the initial orientation, they might use the Earth’s magnetic field to aid them. Once they get close to the coastline, they might check the magnetic field more regularly to get closer to their destination. Once the salmon reach their home river, they might use their sense of smell to help them find the specific tributary in which they were born.
Read all about it: http://bit.ly/W0vq7c
Image source: http://bit.ly/WOO2Hm
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