Given the fact most bulb advertisements would have a person mount a light on top of their birds cage and subject their bird to this for hours, and that this has been shown to be not only without benefit but actually harmful, I feel the need to post information contradictory to this frequently recommended practice. This post will contain relevant quotes from an article on birds and lighting sprinkled throughout. I hope its not choppy reading and instills some understanding. There was a member on another forum, a year or so back who wrote about how her bird got sunburned eye patches and one eye red and swollen for two days due to a cage mounted light.
"The author invites the reader to take a fluorescent lamp assembly and sit with it about a foot or two away from his/her face for twelve hours and then assess if they believe this to be a pleasant experience."
"Placing a device right on top of a bird is unfomfortable and a disturbance to it's visual acuity and metabolic process."
"Whenever possible, mounting from the ceiling is the best and most natural method.............The concept of placing it closer to the cage is an artifact of reptile keeping, and is unnecessary and possibly detrimental for the captive bird. Overhead suspension accomplishes two things. First, the light is directed downward, as it would appear in the outdoors. This ensures that your bird perceives the light as coming from a natural direction. In this manner, light direction cues are delivered consistent with what the avian brain expects to experience. It also makes for a good saturation of light, both visible and invisible into the cage area. Objects are illuminated equally in this fashion, and are placed into proper visual perspective. Secondly, it is easier to control the intensity of light reaching cage areas. Too bright a light is not a good thing. If the area looks over-lit, it probably is. The same rules of visual comfort that apply to humans apply to your bird.
A bird's brain is not in darkness like ours. It receives light through their skulls from outside. We also have to consider that parrots spend most of the day in the shade relaxing, preening, dozing, etc. to avoid overheating and the direct rays of the sun. They are most active in the early morning and evening when sunlight is attenuated by the Earths atmosphere.
To clear up some confusion on the subject of lighting
There are two categories of fluorescent full spectrum:
a)
General Illumination. "A general illumination lamp that may be properly termed full spectrum has a CRI (color rendition index) of greater than 90, and a Color Temperature of greater than 5000K. These devices are
not intended as a source of UV irradiation, but do produce small amounts of UVA (near-range ultraviolet) as a byproduct of their operation."
These are the fluorescent full spectrum bulbs and ballasts available at Home Depot, etc. They are not UVA or UVB (mid-range ultraviolet light) which is involved in vitamin D synthesis. Again, that’s ok because our birds do not need bulbs for vitamin D synthesis…..
“Most pelletized diets, and a balanced natural diet contain cholecalciferol or calciferol, a precursor to Vitamin D3. The presence of UVB is not necessary for birds to convert this form to usable and sufficient levels of Vitamin D. “
But, if this is your goal or purpose in lighting then the only way to achieve this is through a fluorescent UVA/UVB bulb.
b)
Specialty Illumination. These are UVA/UVB, marketed as "Avian Bulbs." They are "Specialty illumination devices, such as the pet series (Vitalite, et al.) and tubes for seasonal affective disorder (Ott, et al.) contain varying amounts of ultraviolet light in the near (UVA) and possibly middle (UVB) ranges in addition to meeting the general illumination criteria. "
Here are some issues with these bulbs:
1)“UVB irradiance is
weak, is
unbalanced negatively in relation to natural sunlight levels, and
does not travel as far from the lamp as visible light. With this in mind, the popular concept has been to place the lighting source as close as possible to the bird to achieve useful exposure for natural pre-vitamin D (cholecalciferol) synthesis “
"When Dr. John Ott was researching the effects of light on various plants and animals, it became quickly apparent that imbalances in the spectrum of light delivered could affect the organism in a variety of ways. Applying this research to humans, imbalances in lighting have been shown to cause depression, lethargy, decreased immune response, and in some cases, agitation and aggressive behaviors. Each factor noted in the human species has a
direct equivalent for animals of all species. "
2) UVB output degrades quickly….
”efficiency will have degraded after six months to where the device is generally useless in playing a part in the Vitamin D synthesis process”
But the dangers of a bulb kept so close to your bird remain…..
3) “Another problem concerns avian visual and endocrine disturbances from the visible and UVA output of the lamp
at close range. Improper lighting can bring on varied health problems; behavioral and breeding disorders which are often attributed to other sources. These symptoms and problems include but are not limited to: lack of strength and endurance; feather and toe picking; restlessness and agitation; decreased immune response; abnormal sex ratios in breeder situations.
Therefore, how could one even consider an arbitrary close distance appropriate for the health and environmental comfort of their bird? “
Stronger UVB output bulbs don't help the degrading and weak output factor but make matters worse:
"Concentrations of UVB in fluorescent tubes can be increased, but due to the amount of barium based phosphors involved,
these devices are no longer lamps which can produce a suitable visible spectrum. When manufactured in this manner, the lamp becomes either a reptile series lamp or tanning (erythemal) device, and must necessarily be regulated or controlled in exposure to prevent damage to humans and animals. The effective life span of these devices is also short, as noted by the previous discussion. Unnecessarily increasing the UVA/UVB to peak levels may cause problems to present themselves in the form of retinal degeneration, cataract formation, and calcium/bone disorders. "
My only purpose in posting this is to avoid harm to our birds through advertisements that are incomplete/misleading and may possibly cause well-meaning owners to harm their birds. I tried to sum it up but for further reading Google author Patrick R. Thrush.