by Pajarita » Sun Jul 14, 2013 8:10 am
Well, the thing with parrots is that they not only regulate their endocrine system entirely by light (duration and quality) but also that they have more photoreceptors (cells that react to light and set off the glandular domino effect that ends up affecting sleep, appetite, molt, breeding, etc) than we do. Mammals (including humans) have only photoreceptors in the eyes so, if we close them, even if there is a bit of light in the room, it won't do anything for us because we can't 'sense' it - but birds have photoreceptors inside their brains with skull bones so thin that light actually goes through them to activate these 'light sensitive' cells and there are studies that show that very light light can screw up their circadian (means 'around one day') and circannual (meaning one year) cycles. These are the biorhythmic cycles that determine everything to a bird's body: when to wake up, when to go to sleep, when to eat, when to breed, when to migrated, when to molt, etc. So leaving a light on at night is not recommended. Some people think that a red light is OK because we, humans, don't even register it when it's a low one at night but red light has the ability to travel through tissue more efficiently and faster than any other light so it's not good for birds.
I don't know why people's tiels have night frights . I've had a flock of more than 30 tiels and none of them ever had a single night fright. I used to think it was because they were not caged but the ones I have now are all handicapped and need to live in a cage and still don't.
But, if you cover her cage and no light is shining into it, it's fine -that's what I do with the birds I keep outside the birdroom and they do just fine.