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Which bird can see the furthest? (1 Viewer)
- Thread starter faserferl
- Start date
IanF
Moderator
Hi faserferl,
I can't help with your query really but I dare say it may be one of the Eagles. However I'd like to take the opportunity to welcome you to Bird Forum on behalf of Admin and the Moderators.
I've copied the thread into this forum where it may attract replies fom those more knowledgeable.
I can't help with your query really but I dare say it may be one of the Eagles. However I'd like to take the opportunity to welcome you to Bird Forum on behalf of Admin and the Moderators.
I've copied the thread into this forum where it may attract replies fom those more knowledgeable.
Edward woodwood
Member
they can see all the way to the Sun in the daytime and a lot lot further at night
level seven
Registered user
john barclay said:
All I know is that birds of all families seem to see me coming along from a heck of a way off....
Edward woodwood
Member
all BOP have forward sight with overlapping 'binocular' fields of vision. If we were endowed with the eyesight of a kestrel it is estimated that we could read a newspaper at a range of 25 yards. If we had the vision of an eagle we would be able to detect the twitch of a rabbit from a distance of two miles. One explanation is the size of the retina. Compared to ours, an eagle's retina is physically larger. The retina is composed of rods and cones, two different kinds of light-sensitive elements. Rods register shape, whereas cones discern colour. The retina of a human eye contains 200,000 rods. An eagle has about a million.
Some bop see a wider colour spectrum than we do: including ultraviolet light. Kestrels hovering along motorway verges are watching for small rodents. At times, it must seem like a search for the proverbial needle in a haystack. However, rodents mark their runs with urine and faeces, which are visible in ultraviolet light. In tests, wild kestrels brought into captivity were able to detect vole and mouse scents in ultraviolet settings. This ability enables them to screen large areas of vegetation in a relatively short time.
Some bop see a wider colour spectrum than we do: including ultraviolet light. Kestrels hovering along motorway verges are watching for small rodents. At times, it must seem like a search for the proverbial needle in a haystack. However, rodents mark their runs with urine and faeces, which are visible in ultraviolet light. In tests, wild kestrels brought into captivity were able to detect vole and mouse scents in ultraviolet settings. This ability enables them to screen large areas of vegetation in a relatively short time.
Tim,Tim Allwood said:
Rods react to light without reference to its wavelength(colour), they have a lower level of reaction than cones and so are mainly used in low light levels giving monchrome (scotopic) vision. Cones need a higher light level to react and according to the most popular theory come in three types reacting to the three primary colours red, green and blue. This gives colour (photopic)vision.
The central field of the retina, the fovea, is circular in humans and consists of cones only, in BOP the fovea is arcuate with a much bigger area than humans but still consisting of cones only.
Shape recognition starts further along the neural pathway and reaches its full in the occiptal lobes of the brain.
Sorry about the lecture but didn't want anyone reading your post to get duff gen, the rest of the post was spot on. :clap:
IanF said:
I believe they do but couldn't find the reference book with the info in it. :h?:
IanF
Moderator
Another snippet I heard or read was that the Golden Eagles of Dumfries & Galloway, Scotland could see the display antics of the single bird at Haweswater, Cumbria and so he may attract a mate.
I'm not sure whether this was fact or just fanciful supposition or perhaps that he may attract a mate heading north to Scotland?
I'm not sure whether this was fact or just fanciful supposition or perhaps that he may attract a mate heading north to Scotland?
IanF said:
If their eye sight was only 3 times as good as ours that would be feasible, the distance is about 90ish miles line of sight. As the figures touted are usually 5 or more times as good as ours then I would think it a strong possibility given clear weather.
joannec
Well-known member
I remember hearing a radio program a year or so ago that was discussing some new research that suggests that swallows and other long distant migrants can actually SEE the earths magnetic fields and this is the secret of their amazing navigational abilites. I can't remember the details but I think the gist of it is that they have special nerves and receptors in their eyes that enable them to actually see the magnetic fields. Does anyone know more about this? It's a fascinating concept.
Joanne
Joanne
I think you're thinking of the research done with pigeons which found natural 'magnets' within the birds brains, the speculation being that sensing the magnet's movement in the natural magnetic field would help with location. There isn't anything about seeing magnetic fields as such. Some birds have natural polarizing filters so can see polarized light very readily, this is usually indicative of bodies of water, so mostly waterbirds with this.joannechattaway said:
joannec
Well-known member
The research I heard about was not with pigeons but specifically with swallows and other long distance migrants. It was reported that they could actually SEE the magnetic fields and clouds obscurred this view which could explain why swallows stay below the cloud layer on overcast days. The discussion resolved around them having a specific part of their EYE which, if I can remember correctly, scientists had identified and are further studying.
Unaware of this research, will trawl net for some insight
Looked on World Ornithological Literature website and no mention of magnetism and vision, one reference to savannah sparrow and polarised light.
Looked on World Ornithological Literature website and no mention of magnetism and vision, one reference to savannah sparrow and polarised light.
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Keith Reeder
Watch the birdie...
IanF said:
Keith Dickinson said:
Eh?
If you were in D&G you'd be hard-pushed to see a golden eagle in Cumbria with the Hubble Telescope, so there's not a hope in Hell that a the Scottish birds could see the English eagles - even assuming they were both on the very highest bit of ground in their territory and there wasn't a cloud in the sky!
Come on, lads! Do you really think you could see birds in Haweswater from D&G with say, a good 30x scope?
No way.
So an eagle - with a nominal 5x better visual acuity than we have - wouldn't stand a chance.
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Rasmus Boegh
BF member
Keith Dickinson said:
Ritz, T, P. Thalau, J.B. Phillips, R. Wiltschko & W. Wiltschko. 2004. Resonance effects indicate a radical-pair mechanism for avian magnetic compass. Nature 429: 177-180.
... and there's been a few follow-up articles on the subject, too.
Allen S. Moore
Well-known member
It sounded a bit amazing, really. I suppose that if it was true, it would increase the likelihood of golden eagles moving to Cumbria from D&G, resulting in there being more than the one golden eagle territory in the English Lake District. Is the Lake District large enough for a few territories, do people more in the know think?Keith Reeder said:
Rasmus Boegh said:
Read the abstract for this article but cannot find specific reference to the bird actually using its eyes to see the magnetic field. This is similar to the research done with pigeons that I mentioned in an earlier posting. The posting I was responding to then had mentioned the birds seeing the magnetic field.
As to eagles seeing from D & G to Haweswater, it would be feasible on a clear day, the eagle would only have to recognise the display flight which would not need the resolution of recognising an individual bird. How often have you watched a raptor in the air, just a dot and been able to get a rough id by its flight behaviour.
