I have a Double Yellow-headed Amazon named Harpo who is 20 years old. A couple of friends came to visit recently and exclaimed over his appearance. They too have an Amazon, but report that her coloring isn’t nearly as vibrant. Harpo is stunningly bright and his coloring is vivid.
I could only point to Harpo’s time regularly spent outdoors in my aviary as the factor that creates that difference. I have always stressed the importance of providing an outdoor aviary for parrots, but my friends’ reactions decided me that I should take another pass at delivering this message.
The information that parrots need specialized indoor lighting or natural sunshine is not new. Full spectrum (FS) bulbs have been recommended for years. But… does full spectrum lighting really meet all of our parrots’ needs? I have attempted below to provide a thoughtful discussion of not only why birds need exposure to ultraviolet (UV) light, but the different options for providing this. Hopefully, this information will not only protect your parrots’ health, but provide valuable help to organize your efforts to provide adequate lighting in a cost vs. benefit manner.
Why Is Natural Light Important to Birds?
The term natural light is often used when discussing light quality. Natural light is composed of a broad spectrum that includes ultraviolet (UV) rays. The normal lighting in our homes cannot be defined as natural lighting for the purposes of this discussion.
Our companion parrots specifically need the ultraviolet portion of natural light for three reasons: (1) to promote vitamin D synthesis and absorption, (2) to prevent diseases directly related to UV deficiency, and (3) to promote overall well-being and quality of life. (Becker 2014)
UV Light, Vitamin D, and Parrots
Both parrots and humans need adequate amounts of vitamin D to aid in nutrient absorption and facilitate metabolic processes. Vitamin D is essential for calcium absorption. If a parrot develops a vitamin D deficiency, she will also suffer over time from a calcium deficiency. This can result in egg-binding, soft-shelled eggs, bone fractures and seizures.
Adequate calcium levels are also necessary for maintaining normal function of the heart, muscles and nerves. (Ritchie, Branson and Harrison, Greg 1997) African grey parrots are prone to hypocalcemia (low calcium levels). However increasingly, this “calcium deficiency” is thought to be the result of low vitamin D levels.
Vitamin D deficiencies been implicated in the avian disease known as “stargazing.” They are also thought to be involved in Conure Bleeding Syndrome and in some types of cancer. (Becker 2014)
Three Options for Vitamin D
The precursors to the more active form of vitamin D3 can be obtained from food. Certain foods are better sources than others. However, dietary sources may not be the most efficient way for parrots to get enough vitamin D3.
We don’t know how well parrots absorb this nutrient from their diet. This is because they have evolved an amazing ability to synthesize this vitamin through exposure to natural sunlight. It is possible that they may have a decreased ability to absorb vitamin D from their diet, due to this ability. There is much to be discovered here and to date there have been no species-specific needs established.
Most parrot species have an uropygial gland located at the base of the tail. Referred to as the “preen” gland, it exudes a fatty, waxy substance. (In Amazon parrots and some macaws this gland is absent; it is believed that these species get vitamin D from skin exposure.)
Secretions from this gland contain a compound that produces vitamin D when exposed to the sun’s ultraviolet rays. As a parrot preens under light from a source of UV rays, she ingests the vitamin D that she’s been creating while preening. This compound is then converted by the liver to the more usable form, Vitamin D3.
Parrots also absorb vitamin D through the eyes. (Becker 2014) Humans’ eyes filter out UV light, but parrots’ eyes do not. A parrot’s eyes will absorb red, green and blue light, but also UV light. Birds also have an additional structure around the retina, called the Harderian gland. This aids in the absorption of UV light into the retina.
Moreover, this gland communicates with the pineal and pituitary glands to help regulate breathing, molting, day and night cycles and, in some cases migration. (Becker 2014) Since a parrot’s metabolism and overall health are regulated by the pineal and pituitary glands, it is essential that parrots have adequate access to UV light on a regular basis. We cannot assume that dietary sources are sufficient.
Quality of Life
While we have good documentation regarding the health benefits of FS light, we have little information as to how it impacts other factors relating to quality of life. This is obviously difficult to document through research. We must rely on anecdotal information from those who provide lighting to their parrots. Dr. Becker reports that access to ultraviolet light improves the following:
- Feather damaging behavior
- Poor feather quality
- Organ dysfunction
- Immunologic disorders
- Poor mood and temperament
I believe the last claim to be absolutely true. I can send five snarky, irritable, bored parrots out into the sunshine in the morning and in the evening, I bring in five relaxed, happy birds. It’s like magic. Just as we experience greater well-being and relaxation after spending time outdoors, so do our parrots.
It’s A Need, Not a Want
The need to actively provide a specific type of lighting then is not in dispute. Parrots who do not receive either indoor full spectrum lighting or access to sunlight in an outdoor aviary are at risk for illness and poor quality of life. Formulated diets and the natural lighting in our homes are not enough. “Overall, the benefits of UV light warrant that every companion parrot should receive some exposure.” (Wade 2009)
This brings us then promptly to a discussion of full-spectrum lighting versus natural sunlight. How do we want to provide for our parrots’ light needs?
Full Spectrum Bulbs
The ultraviolet light spectrum consists of three kinds of light: UVA, UVB and UVC. Birds and reptiles can see UVA wavelengths; we cannot. (Wade, Laura 2009) The UVA portion assists parrots when selecting mates and identifying ripe foods. It is the UVB portion that helps them metabolize vitamin D. UVC is filtered out by the earth’s atmosphere, so is not a concern.
Windows and fine mesh screening filter out the UVB portion of the ultraviolet spectrum. Thus, sunlight that comes in through a window does not protect your parrot’s health. (Windows do not filter out the UVA rays, which is why your carpets will still bleach over time when sunlight hits them through a window.)
If you are thinking about providing FS lighting, there are six things you must know. Few people really have the facts about full spectrum lighting. There is a great deal of misinformation in print, as well as a lack of information provided by the industry who sells these bulbs. Most of the information in print was extrapolated from use with reptiles, which is inappropriate. Reptiles and birds have different lighting and dietary needs. (Thrush 1999) This is what you need to know:
#1: The words full spectrum create confusion. This description can be used by manufacturers to advertise bulbs even if they do not emit UV rays. In these products, the term full spectrum merely means that the range of light emitted is visible to the human eye. They may emit UVA rays, but not the UVB that your bird needs. You must purchase a specialty bulb manufactured just for birds.
#2: The UVB rays emitted from even the specialty lights are much weaker than the total component of visible light that they produce. (Thrush 1999) It does not travel as far from the lamp as the visible rays do. Thus, most recommendations call for placement of the bulb as close to the parrot as possible without resulting in corneal damage or burning of the skin.
A typical recommendation is as close as 6 inches from the parrot’s head and no further than 12 to 18 inches away. This means that to get adequate exposure, your parrot has to sit directly under the bulb. If he spends much time on the bottom of his cage foraging or away from the cage, he is not benefiting from the UVB rays the bulb produces.
#3: Birds have much thinner skin than do mammals. Their corneas also are thinner. This is why they are more sensitive to UV light. This puts them at risk for developing corneal inflammation if UV bulbs are used incorrectly or have an output that exceeds recommendations.
Such a case was documented in a Meyer’s parrot. Testing of the bulb in this case revealed very high levels of quite low UVB light emitted. Another documented case involved “skin burning” in an African grey after the initial introduction of a new UV bulb. According to Dr. Wade, “…increased damage from high intensity, low-wavelength UV light may increase the risk of cancer and cataracts over time.” (Wade 2009)
#4: Since UV lighting has become so popular for parrots, there has been a rapid increase in the manufacturing of these and the types that are available. Unfortunately, there are no industry standards in place. Dr. Wade has done extensive testing of available bulbs and has found a large variance in emissions.
She recommends either the Arcadia Bird Lamp linear tube or the Duro-Test Vita-Lite linear tube for low UVB needs. Parrots who might benefit from higher emissions include those eating a seed diet, those who don’t get any natural sunlight, or that are laying eggs. For these parrots, she recommends using either the ZooMed Reptisun 5.0 linear tube or the Hagen ExoTerra Reptiglo 5.0 linear tube. (Wade 2009)
She specifies linear tubes as best for birds if UV light is provided during the winter months. During the warmer months, she urges caregivers to provide their birds with 20 to 30 minutes of unfiltered sun exposure two to three times each week.
#5: The output of UV light from your full spectrum bulb will decrease over time as it ages. We cannot depend upon manufacturers’ statements regarding lamp life; these merely reflect the time at which we might expect the bulb to stop working.
It is phosphors within these bulbs that produce the light rays. The phosphors that produce the UV rays are different than those that produce the visible light. Those that produce the UV light degrade at a much faster rate. According to Thrush, after 3000 hours of operation the levels of UVB emitted from the lamp will have decreased by 20 percent. Therefore, full-spectrum bulbs should be replaced every 6 months, even if the output of visible light hasn’t changed. (Wade 2009)
#6: FS bulbs are florescent bulbs and are rated as to their Color Rendering Index (CRI). This CRI rating reflects the bulb’s ability to make colors appear and is measured on a scale of 0 to 100. Natural sunlight at noon has a CRI of 100. Most indoor lighting has a CRI in the 60s or 70s. Even some FS bulbs will have a CRI as low as 85. For correct color perception, parrots need a CRI higher than 90. This is yet one more factor to consider when choosing a bulb.
The CRI also reflects the speed at which the light is emitted. Not only do birds see a larger portion of the color spectrum than we do, they are able to see at a faster speed. Light is emitted in wavelengths. When the speed of light is too slow, parrots will not perceive it as continuous light. They will see a flicker. This can create visual disturbances and is another reason to purchase a bulb with a CRI of 90 or higher.
To summarize, if we are going to use full spectrum bulbs we must (1) choose carefully giving thought to type and CRI rating, (2) place them no further than 12 to 18 inches from the parrot, and (3) replace them every 6 months. While most veterinarians recommend using full spectrum bulbs at least during the winter months, cautions exist and some question whether FS lighting could diminish quality of life outside of health concerns.
Dr. Becker reminds us: “Nothing man-made can ever completely replace the health benefits nature provides in clean, fresh air and sunlight.” Dr. Wade describes natural, unfiltered sunlight as “ideal.” Thrush is more direct: “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.”
The Outdoor Aviary and Other Options
If these facts about FS lighting cause you to reconsider its use, an outdoor aviary is the ideal. Please don’t disregard this as impossible before considering all the facts. The investment in an aviary will produce a lifetime of benefits to you and your birds.
Every individual who has purchased an aviary upon my recommendation has come back to me with gratitude. Wendy describes her aviary as “The most important tool besides the Kings 506 we have to successfully keep Georgie Pink Superstar. It was critical in bringing along Alison when she arrived. I will never forget her first day in the aviary. Her face in the sun reflected absolute joy. Additionally, as a caregiver trying to provide for large cockatoos, it keeps my sanity at times.”
David says: “I am very happy that I was encouraged to have an outdoor aviary–enough to move it halfway across the continent! Parrots receive natural full spectrum lighting. They can see other birds and outdoor phenomena safely. They feel the wind and weather in their feathers and across their bodies, and are able to exercise in a different way. It’s a different sort of mental and physical activity.”
Providing an aviary is a “win” for all. Parrots enjoy their birthright – sunshine, rain, wind and the stimulation of that combination. They move around more. They enjoy bathing in the rain. For further enrichment, an aviary can be planted with vegetables, flowers and herbs for foraging.
Time spent in an outdoor aviary will also do wonders to calm down a “hormonal” parrot and I believe that recovery from feather damaging behavior may depend in some cases upon exposure to sunlight.
The benefit to the humans in the house is just as significant. Parrots have large personalities and it can be nice to have a short break from them. If the aviary is constructed well, supervision of the parrot(s) is not necessary after a period of introduction. A well-constructed aviary will provide adequate safety, even in your absence.
If you are convinced, your options will be to build from scratch or purchase a pre-fabricated aviary. I strongly encourage you to choose the latter. For safety from predators, your aviary should be constructed of galvanized wire that is at least 14 gauge (12 is better) and has a spacing of ½-inch by 3 inches. Having done it, I can tell you that working with this wire is no party. Further, if you construct an aviary yourself, you won’t be able to take it when you leave.
There are many sources for pre-fabricated aviaries. One company I recommend is Corners Limited. Presently, they have a wait time of 6 to 8 weeks. However, the quality of these aviaries is excellent. They are easy to set up, attractive, and can be moved. They can be powder coated if you are concerned about the safety of galvanized wire.
If an aviary is absolutely out of the question, other options exist. You can provide another parrot cage on a deck or other place of safety. However, the bar spacing of most will pose a danger if raptors or other predators are nearby. Constant supervision is necessary.
Another option is the Cageoller. This is essentially a cage on wheels that can be taken for walks or simply moved outdoors. Again, supervision is necessary.
If we provide an aviary or other safe option for getting our bird outdoors, we don’t have to concern ourselves with all the uncertainties that can accompany the use of full-spectrum bulbs. We can rely on our parrot’s inner wisdom to limit their time in the sun, which they will do. It is absolutely the best option for your parrots.
Ritchie DVM, Branson and Greg and Linda Harrison. Avian Medicine: Principles and Application. Lake Worth: Wingers Publishing, Inc., 1997 Abridged Edition.
Wade DVM, ABVP, Laura. “Ultraviolet Lighting for Companion Birds: Benefits & Risks. 2009. http://www.buffalobirdnerd.com/clients/8963/documents/UVlightingBirds.pdf