The Dog’s Color Vision and What It Means for Our Training

Dog Sniffing

When training dogs in any scent detection discipline, we should use colors that are difficult for them to see so to compel them to use their noses (and not their eyes) to find the target (picture from Joy of Living).


Do dogs see colors? Does that affect our dog training in any way? These are the questions I will answer today.

In the early 1980s, we performed some tests at the Ethology Institute Cambridge to determine whether dogs were colorblind as the popular view says. The conclusion of our experiments was that they could distinguish between some colors and could not discriminate certain other colors. They are not completely color blind (seeing only shades of gray). They were more like some people who see colors though not the full spectrum. However, we could not determine, at the time, whether the color discrimination of the dogs was due to differentiating between real colors or various shades of gray. Meanwhile, more modern research has cast some light on these questions.




Eyes contain light catching cells (cones) that respond to color. Canines have fewer cones than humans, which implies that, in principle, their color vision cannot be as good as ours. To see colors, we need various types of cones, which can detect different wavelengths of light. We have three types of cones, which gives us the possibility to register what we call the whole range of color vision.

Researchers at the University of California at Santa Barbara tested in the late 1980s the color vision of dogs. Their studies confirm that dogs see color, though not as well differentiated as humans do. For us, the rainbow looks violet, blue, blue-green, green, yellow, orange and red. For a dog, we presume it looks dark blue, light blue, gray, light yellow, darker yellow, and very dark gray. They seem to see violet as blue (like many humans).




Studies performed by Russian scientists demonstrated that dogs tend to discriminate real color rather than brightness cues. Dogs have a dichromatic color vision, which means that they have two types of cones in their eyes. They match any color they register with no more than two pure spectral lights. Placental mammals are in general dichromatic. The ability to see long wavelengths necessary to distinguish red from green seems to have disappeared during evolution, probably after the Triassic period. Dichromatic vision is, though, good to distinguish colors in dim light, favoring the most nocturnal animals.

Trichromats, like most humans, have three color-detecting cones (blue, green and red) and can distinguish between 100 different gradations of color. Honeybees are also trichromatic seeing ultraviolet, blue and green instead of blue, green and red.


Dog color vision.

Human = A and C. Dog = B and D. It is difficult for the dog to discriminate between red and green.


The term color blind is, therefore, somehow misleading. Some animals developed the ability to see some colors and others to see other colors all depending on what mutations appeared and the subsequent costs and benefits each strategy implied for their struggle for survival.

What does this mean for our communication and training of our dogs? Since dogs find it difficult to distinguish between certain reds and greens (like some humans do), we should choose toys and training aids in other colors. For example, light blue or yellow are much easier colors for a dog to detect. On the other side, when training them in any scent detection discipline, we should use colors for the targets that are difficult for them to see so to compel them to use their noses and not their eyes.


Kasparson, A. et al. 2013. Colour cues proved to be more informative for dogs than brightness. Proceedings of the Royal Society.
Neitz, J. et al. 1989. Color Vision in the Dog. In Visual Neuroscience, 3, 119-125. Cambridge University Press.

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Do You Like Canine Scent Detection?

Our new Canine Scent Detection Course consists of two parts or two lessons: lesson 1 theory, which you can take online, and lesson 2 practice, which you can take by attending one of my workshops. Chances are you’ll find a convenient location, for we are planning three in the USA, three in Europe, two/three in Australia/New Zealand and one in Mexico. Please, visit our Facebook page regularly for more news.

For more info and a video clips from our canine scent detection workshops, please, go to the course page. The workshops run typically over three days with most teams passing the double blind test on Sunday afternoon. Watch the videos and you’ll be surprised with what we achieve in only three days.


Nosework in 1984

Illustration by Alice Rasmussen for my book from 1984 where I write that næsearbejde (= nose work) is not only for the professionals but for all companion dogs as well independently of the breed.


Scent detection has fascinated me since my early days as a student of biology and I was training detection animals already at the beginning of the 1980s. I have trained dogs, rats and guinea pigs to detect narcotics, explosives, blood, vinyl, fungus, landmines, tuberculosis, tobacco—and they excelled in all fields.

Almost all my detection work has been for the police, armed forces or other professional agencies. Yet, I wrote about scent detection in the beginning of the 1980s in my first book, “Psychology rather than Power,” which was published in Danish. Back in 1984, I called it “nose work” (directly translated from the Danish = næsearbejde). I recommended all dog owners to stimulate their dogs by giving them detection work starting with their daily rations. We even did some research on that and the results were extremely positive: the dogs stimulated by means of detection work showed improvement in many aspects of their otherwise problematic behavior. My recommendation remains the same. Physical exercise is, of course, necessary, but do not forget to stimulate your dog’s “nose” as well, maybe its primary source of information about its world.


Roger Abrantes in 1984 with a Siberian Husky.

Yours truly in 1984 with a Siberian Husky, an “untrainable” dog, as everybody used to say. This was when my book “Psychology rather than Power” created a stir. We were then right at the beginning of the animal training revolution.


I write this blog 30 days after I started. 30 days, 30 blogs, 75, 764 readers and 187,756 page views. Yes, I’ll continue blogging as long as you keep clicking that magic button “like”— my reinforcer.

I won’t hold you any longer. I know you want to go and click the course link to watch the movies. Enjoy!

PS—Please, don’t click all at the same time. Our server has been boiling since last week.


Roger Abrantes

Canine Scent Detection

Dog Sniffing Bag

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