UV and Reindeer — finally some real science!

I’ve been about ready to bust for months. Here it is September, past the middle of the month, and no one has asked about UV Suppression. Dang! What’s wrong here? Don’t tell me y’all been listening to me and wised up? You mean I’ve been holding back all this anti-UV vitriole for a year, and no one wants to get me wound up?

Guys, this is a sorry state of affairs. Between this and the Bengals winning their opener, you’d think the world was coming to an end.

Okay, since nobody wants to ask the magic question, I’ll have to ask it myself.

So shaman, what’s  your opinion on UV suppression?

Funny you ask.

I was digging through a pop-science site back last Spring, when I ran into an article about reindeer and UV. Yikes! It was an epiphany. For once, here was some real scientific study on the underpinnings of this whole UV thing.

Look, all this supposed scientific study about UV Suppression and whitetail deer really has never answered some basic questions. They know a whitetail’s eyeball can sense UV. That’s about it. The rest of it? Conjecture, hype, hoo-haw, smart marketing and spin. I laid probably the most fiendish part of the whole plot out for you last year:

. . . The UV brighteners in clothing? All that piffle with the black light and such? Nonsense. If you have a fabric or any substance that glows under black light, it is not sending out UV. If it did, you could not see it. Rather, UV brighteners in fabric, detergent, etc. are fluorescing. What that means is they are absorbing one frequency of light (UV ) and retransmitting it in another visible part of the spectrum. Let’s all take a deep breath and give a big DUH!

However, the question remained for me: So assuming deer see UV, how does that figure into their survival? For instance, we can see the color Red. Does that mean we are attracted to red or repelled by it? The answer is sort of complex, isn’t it? A flashing red light may mean warning. It could also mean we are approaching a brothel. A red piece of food might be a cherry Gummi bear or a red hot Mongolian pepper, right? With deer and UV, what does it mean?

Read this  article on reindeer from from ScienceCodex.com:

From ScienceCodex.com

According to this, reindeer see in UV as an adaption to dealing with snow. They see the UV reflecting off snow. What makes them alert to danger? The lack of UV coming off urine-stained snow caused by predators as well as the lack of UV coming from the fur on the predators themselves. It also helps them find lichen.

Professor Jeffery continued “When we used cameras that could pick up UV, we noticed that there are some very important things that absorb UV light and therefore appear black, contrasting strongly with the snow. This includes urine – a sign of predators or competitors; lichens – a major food source in winter; and fur, making predators such as wolves very easy to see despite being camouflaged to other animals that can’t see UV.”

What does this mean to you, the hunter?

Simple: At least in the case of reindeer, UV sensitivity is an important survival adaption, but only because they have to deal with snow. White snow reflects UV. White fur does not. Therefore wolves, polar bears and the like will show up darker on a snow field to a reindeer. Also, it allows the reindeer to spot urine on snow a little better. With whitetail, the issues may be the same. They can see UV, but the things that get them honked off are things that ABSORB UV like fur and. . .UV Suppression products. Think about it!!! Maybe instead of going out and buying UV-suppression products and spraying them all over our gear, we should be throwing out our fur hats. I have a black light that ATSKO sent me. Probably I should do a study down the basement soon to see if real fur is darker under black light than fake fur and fleece. My guess is that it is. However, by the time you figure in things like tree bark, dead leaves and the rest of stuff you find in the forest, the whole thing is so jumbled, I do not think a fur hat would amount to much. However, it might if you were walking over a field of snow.

That is really what I think; with whitetail, it is a mostly vestigial ability. The UV receptivity really only gives them an edge when they are dealing with vast amounts of show and most whitetails never get more than a short distance from the woods. In forest, even snow covered ones, the advantage of sensing in the UV range quickly attenuates. Bottom line: it means nothing to us and very little to deer.  Of course all of this is just my opinion.

Okay. I have vented my UV-radioactive spleen for the year. I feel better now.



UV and Reindeer — finally some real science! — 1 Comment

  1. Gaffer,

    You have understood the difference between UV reflection and fluorescence, which is more than Atsko has done; however, you need to appreciate that most humans cannot see in the near ultraviolet. Although if you remove the lens of the eye in cataract surgery, you will see in the UV. The adult human lens contains a yellow pigment that absorbs most of the incoming UV wavelengths; children lack the pigment, so they have rudimentary UV vision. OTOH, a white-tailed deer doesn’t have these yellow pigments and is always capable of vision in the ultraviolet. Their flag (tail) is highly UV reflective, enabling them to follow one another at high speed in dim light.

    As for turkeys, they, like most diurnal birds, have four types of cones in their eyes – for red, green, blue, and UV. Ducks, geese, as well. Also trout (an outrageous plug for my book “The New Scientific Angling – Trout and Ultraviolet Vision”).

    Just like visible camouflage, you should use UV camouflage that reflects the same percentage of UV as your surroundings.

    Sorry for the tirade. Have a good weekend.

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