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Xantara
20-09-2005, 12:28 PM
If an owl only gets to see in black and white what does a hawk see and is it different for a falcon ?

anyone

xan




Boobook
20-09-2005, 01:00 PM
I though that owls could see colour!? Less well than us sure but not just B&W?

Boobook
20-09-2005, 01:23 PM
More from the BBC...

The power of sight is of paramount importance to birds-of-prey, all of which have forward sight with overlapping ‘binocular’ fields of vision. Acuteness of sight is difficult to define but 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. Better still, 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 for hunting birds’ phenomenal eyesight is the sheer size of the retina. This is the screen at the back of the eye on to which the lens casts an image. 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. However, you ain’t seen nothing yet.
In 1995 the mind-boggling discovery was made by Finnish researchers that some birds-of-prey see a wider colour spectrum than we do: including ultraviolet light. How might this be useful? Kestrels are a familiar sight hovering along motorway verges and grassland. They are watching for small rodents. Their quarry is fast and nimble and ranges over habitat that is often uniform and extensive. At times, the kestrel’s task 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 latrine scents in ultraviolet settings. This ability enables them to screen large areas of vegetation in a relatively short time and to concentrate hunting at ‘busy intersections’. Does this mean they possess the world’s best traffic camera?

Saker-Clive
20-09-2005, 02:10 PM
I've asked this very same question before.............................apparently, falcons and hawks eyesight is 30 times better than ours!! This being the case; from where I live in Sussex, on a clear day, we can see the Isle of White, which I guess as the crow flies is about 60 miles away.
If this is so; when a falcon is 1500 feet up or more; just HOW far can they see or is their sight tuned more for movement........................
From a great height on a clear day, a falcon in theory could quite easliy see 150 miles!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Maybe one of the resident vets might shed some light on the subject.

Hawkmaster
20-09-2005, 03:15 PM
falcons and hawks eyesight is 30 times
8 TO 8 1/2 TIMES BETTER.

Xantara
20-09-2005, 05:06 PM
so they can make out the hawkmaster logo on your vest and get back safe then :)

Questions like this always intrigue me because ultimately we cant for sure answer it i guess. I heard it said at the fair at the weekend that owls only do black and white thats why I asked thought it was interesting. Do birds get startled by colour then does anyone have experience of that ?

North East Harris Hawker
20-09-2005, 09:14 PM
apparently BOP have the most evolved eyesight out of any creature on the planet :shock:

Wightwings
20-09-2005, 09:35 PM
i would agree Lee.....interesting subject this one