A couple of months ago I go a UV lamp for my African Grey
(Rocky) and have it switched on from the morning until evening for around 8 to
12 hours daily.
Birds are similar to reptiles in regard to their natural
sunlight requirements. Both animal groups use sunlight to produce vitamins and
hormones in their bodies and both use unfiltered (not through a window pane) sunlight
to view the world. By denying a captive bird access to unfiltered sunlight or a
synthetic source of UVA and UVB we effectively deny the bird the right to see
as nature intended and produce the vitamins and hormones that they require in
the way that nature designed them to.
Tetrachromacy is the term used to describe the addition of
the all important fourth cone cell in the eye of birds, reptiles and some fish.
The inclusion of these four cone shaped cells and the oil droplets that they
contain effectively opens up a whole new world to these remarkable animals.
Humans using three rod cells (trichromacy) can only reportedly view the world
with around one million colours. Tetrachromats are able to see around 100
million colours, that is a massive difference. Humans as usual don’t seem to be
able to truly grasp just how important this maybe to birds, maybe it is because
we cannot experience viewing the world in the way in which birds do. The
inclusion of this fourth cone cell allows the bird to see wavelengths of light
that humans simply cannot see i.e far into red and blue and also into the ultra
violet wavelength. I have watched the fantastic BBC series on DVD “the life of
birds”. Why did the bib of the budgerigar glow when exposed to a black light?
These black lights emit a lot of UVA, this then allows a human to see UV
reactive patches on birds and things like banknotes. Birds and reptiles both
appear to wear badges! Special fluorescent patches appear on the feathers and
scales when viewed under the correct wavelength of light and using the gift of
tetrachromacy. Humans cannot see UV so we have to use a black light to view
these patches. Birds can see them all of the time if the tetrachromatic ability
is “activated” by providing exposure to UVA. These fluorescent patches seem to
show the differences in the sexes especially in the monomorphic species,
health, condition and breeding readiness. It has also been shown now that UVA
effects how birds view potential food sources. Tetrachromacy in the wild helps
birds find food. It seems that riper fruits are easier to spot in dense foliage
with the benefit of Tetrachromacy. The waxy surface of these fruits seem to
show up like a neon sign to birds. For softbill’s the theory is the same.
Insects also display these patches, so a fast moving or hidden insect could
actually to a bird be a shining beacon of a display sign that says “here is
food”. I have also read studies showing that poisonous insects and plants seem
to display warnings using these flouro patches that they are not good to eat.
Yellow flowers reportedly show as bright red, humming birds use this gift to
spot the right flowers with good amounts of nectar. Raptors use Tetrachromacy
to see the urine trails left by rodents as they travel through their runs.
Great eyesight is coupled with the ability to see these urine markers, this can
then show the raptor a potential food source even in dense foliage. Rest
assured the more you study Tetrachromacy the more interesting and addictive it
becomes. So Rocky would have this unfiltered sunlight in the wild but being
domesticated this is no longer the case, especially with our Scottish weather
which is far removed from the Congo in Africa.
Bird lighting is one of those products that show’s results
almost immediately. As soon as the lamp is switched on you will generally see
the birds become more animated. In the case of song birds the cocks usually
break out into spontaneous song. Rocky
perks up and actively basks. He opens his wings and ruffle his breast feathers
to allow exposure to his skin. I have
the lamp shinning in one part of his cage so he can move out of the light if he
so desires.
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