By Linda Cole
If you are in the habit of taking your dog for a late night walk, it’s always a good idea to carry a flashlight to look for other animals that might be wandering about. It’s important because you certainly don’t want to be surprised by a predator that could put you and your dog at risk. But can you really tell what animal is lurking in the darkness by the reflective color of their eyes? Read on to see.
I like to hide CANIDAE treats around my dogs’ pen to give them some stimulation hunting for them. Occasionally they miss one or two treats, which means some wild critter will find the tasty tidbit sooner or later. While checking the pen one night before putting the dogs outside, the beam from my flashlight caught a blue reflection from an animal on the other side of the fence. Then another pair of green eyes was staring into the light. It turned out to be a couple of raccoons. What’s interesting about the reflective eye color of animals is that the color can vary for different reasons. Raccoons can actually have green, yellow or blue reflective eyes.
The eyes of cats and dogs see best in the low light of twilight. They are classified as crepuscular rather than nocturnal, but both species are hunters who can see well enough to catch nocturnal prey. Animals of the night have eyes that are designed to help them see better in the dark, with a special surface just behind their retina called the tapetum lucidum that reflects light. It’s a mirror-like reflective membrane that sends light back through the retina a second time, giving the light an extra chance to hit rods which are sensitive to light. This enables nocturnal animals to use all available light to help them see, and the reflective light of their eyes we pick up in a flashlight beam can give us an idea of which critter is staring at us – but it’s not reliable. Observing how the animal behaves and how far off the ground the eyes are is a better way of knowing if it’s a deer, coyote or another animal.
It can be unnerving to see an animal watching you when a flashlight or other light source reflects off their eyes. You can get a general idea of which critter has you in their sight, but the color of a specific animal can vary depending on the angle and type of light source (LED or incandescent from a flashlight, car headlights, moonlight). Reflective eye color can also vary depending on the animal’s age, health, amount of zinc or riboflavin in the tapetum lucidum, amount of pigmentation inside the retina, eye color and distortions within the lens. The colors produced by the tapetum can be white, green, blue, yellow, orange or red. Alligators and crocodiles are famous for their red reflective eyes at night. It’s possible for two animals from the same species to have different reflective eye colors.
When you shine a light at whitetail deer, they generally stand and stare back with white, green or yellow reflective eyes trying to figure out if you’re friend or foe. The distance of the eyes from the ground depends on if they are lying down or standing. A wandering coyote will give your light a passing glance as he tries to get out of it. He will look back at the light, but doesn’t stare at it. Their eye color can be a yellowish-green. Cats will often give you a good look at the color of their eyes, which can be green, yellow or red, but they also give you glances as they try to get out of the light as soon as possible. Opossums can have a red, greenish or white reflective color and may look away, but they are more apt to keep staring, especially if looking down from a tree. If you see small white eyes staring at you from the grass or close to the ground, it’s probably a spider or mouse. Dogs can have a blue, yellow, green, orange, turquoise or red eye shine. Red is likely caused by the light reflecting off of blood vessels.
It’s prudent to be aware of your surroundings, especially at night, and know the nocturnal animals that live and hunt in your area. You might not be able to identify an animal by reflective eye color, but you can usually tell by their behavior. Knowing what to look for can help keep you and your dog from a confrontation with a nighttime predator.
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