Full spectrum lighting

[findi]

Some thoughts and info on full spectrum lighting, what we do in zoos, ideas for home; what is your experience? Providing the Proper Type and Amount of Light to Pet Birds | That Bird Blog

 

[DebsFlock]

BUNCH of recent threads on this forum on this topic, you may want to do a search.

Bottom line is that if a bird gets an average of five minutes a day most weeks of exposure to sunlight that is not filtered through glass or plastic, a full spectrum light is not necessary.

If not, they do need exposure to UV-B for health (and they actually see into the UV-A part of the spectrum FWIW) so you would then want to use full spectrum supplemental lighting.

You need to be careful to find a bulb that is really full spectrum -- not daylight balanced. It is not uncommon for hardware store bulbs or home-decorator bulbs to be mislabeled. True UV-producing bulbs are pricey and need to be replaced every 6 months as the coating that produces the UV will wear out, basically. You won't see any difference in the visible part of the light, but it needs replacing anyway.

I got Aviansun to send me a spectrum once, demonstrating the bulb really does produce UV light. Since UV is essentially blocked by normal glass, this is tricky, which is why the bulbs are pricey.

 

[Featheredsamurai]

My avian vet said if they don't get exposure to sun (no window or screen in the way) they need a UV light on for 8 hours a day.

 

[MaraWentz]

I was told that they need at least one hour of full spectrum lighting of pure sunlight, but the more they get the merrier

 

[DebsFlock]

My avian vet said if they don't get exposure to sun (no window or screen in the way) they need a UV light on for 8 hours a day.

I'm going to quibble a hair here. Sunlight coming through a screen, like normal windowscreen netting where you can see how big the holes are, WILL contain the same proportion of UV-A and UV-B as unadulterated sunlight. The only issue is that the overall brightness is reduced, so instead of 5 minutes a day, an hour might be more appropriate, depending on how bright the sunlight is.

UV A/B light has a wavelength around 200-400 nanometers. That's less than one ten-millionth of an inch. Standard window screen mesh has holes a bit smaller than one tenth of an inch. Trying to block UV with a hole that size is like trying to restrain mice using a cage with bars 50 miles apart. The UV doesn't know the mesh is there, it's all about the total quantity of sunlight. This is NOT true of glass or plastic and may not be true of certain types of cloth.

 

[MaraWentz]

I was told the screen filters out Uvs and thought that was odd lol

 

[Riio]

Sooooo, do they have to be directly in the sun? Or just outside where the light gets them, like in the shade? Its been hot here and dont want lil one in the direct sun to cook.

 

[MonicaMc]

Indirect will work just as fine as direct... the rays bounce around, so in the shade, there will still be some amount of UVB/UVA rays getting to you and your birds.

 

[DebsFlock]

Indirect will work just as fine as direct... the rays bounce around, so in the shade, there will still be some amount of UVB/UVA rays getting to you and your birds.

Yep. The trick is that the total illumination adds up to about the same. If the light in the shade is half as bright, you need to spend twice as much time.

 

[findi]

Hello All,

Sorry for the delay in getting back on this. I've been involved with research on this matter, and re reptiles, in conjunction with veterinarians during my years at the Bx Zoo. While far less sun that UVB bulb exposure would be adequate, there is a good deal of variation by species, locale, season, and so on...I'm in touch with someone working on this, and will update. Work with reptiles has established that screeing does cut down on UVB penetration - more significant with bulbs than with sun. Metal reflectors counteract this a bit, by bouncing rays back into the cage. I advise folks to go with bulbs designed specifically for birds, rather than hardware store models. Far more work has been done with reptiles, re UVB/UVA, but thisdoes not directly translate into usable info for bird owners; some is useful however, pl let me know if you need further info, Best, Frank

 

[DebsFlock]

Screen will cut down on the total illumination, by the amount reflected away by the wires in the screen, but it should not single out the UV. The wavelength is so short it's not going to cause diffraction.

Another way to say it is that screen with holes big enough you can see won't alter the spectrum of the light until you get way out the red end, in the infrared. Until the size of the holes/wires and the wavelength of the light become comparable, it's like throwing balls through windows, you don't get effects like diffraction or interference to any significant degree. You can miss the window and bounce back, but as long as the ball is much smaller than the window, the probability of bouncing back isn't affected by the size of the ball.

OTOH, if the wires cover 20% of the area, you'll lose 20% of the light in all wavelengths.

 

[findi]

Screen will cut down on the total illumination, by the amount reflected away by the wires in the screen, but it should not single out the UV. The wavelength is so short it's not going to cause diffraction.

Another way to say it is that screen with holes big enough you can see won't alter the spectrum of the light until you get way out the red end, in the infrared. Until the size of the holes/wires and the wavelength of the light become comparable, it's like throwing balls through windows, you don't get effects like diffraction or interference to any significant degree. You can miss the window and bounce back, but as long as the ball is much smaller than the window, the probability of bouncing back isn't affected by the size of the ball.

OTOH, if the wires cover 20% of the area, you'll lose 20% of the light in all wavelengths.

Earlier work done with reptiles is not exactly in line with the above, but on a practical level a reflector will do away with concerns when using a bulb, and sunlight will deliver ample UVB through screening in most situations.
Best, Frank