Reflections in nature: Daylight saving time coincides with peak deer hours

The Pennsylvania Game Commission has advised motorists to slow down and stay alert as deer become increasingly active. Daylight saving time, which ended on Saturday, saw an increase in vehicle traffic between sunset and sunrise, which coincides with peak times for deer activity.

Deer become more active in the fall leading up to their fall breeding season, commonly called the rut. Around this time of year, many yearlings disperse from the areas where they were born, sometimes traveling dozens of miles to find new areas. Adult bucks often travel through their habitats in search of deer. If a doe is encountered, the buck will sometimes chase the doe.

While I’m driving, Mary Alice often reads or does crossword puzzles, but when she goes home at night on Route 14, she’s always on the lookout for a deer that might be on the road or along the road.

All nocturnal animals have so-called eye shine, caused by tapetum lucidum, a Latin word meaning bright carpet. This tapetum lucidum, which lies behind the retina, reflects light back through the retina, increasing an animal’s superior night vision. When artificial light falls on an animal’s eyes, the eyes appear to glow.

Although deer have yellow eyes, dogs and cats have green eyes, coyotes green-gold, opossums dull orange, skunks amber and foxes white. I have never read the following in a book or magazine, but an old raccoon hunter once told me that a male raccoon’s eyes have a red glow, while the female’s eyes have a yellow glow. He went on to say that this only includes adults.

Most nocturnal animals have acute hearing, sensation, smell and night vision. There are some animals, such as the bat with its radar hunting, that have additional skills. The great horned owl uses its ears to find prey. This owl’s ears are located in the facial disc, with one ear located higher on the head than the other. The great horned owl must turn its head until both ears pick up the same decibel sound.

At this exact moment the owl will look at what is making the sound and be able to see its prey.

Nocturnal animals use the same space and eat the same food as diurnal animals. During the day, insect-eating birds feed on nectar-sipping butterflies. At night, the nightjar family (whipworms and nighthawks) feed on nectar-sipping moths and other insects.

Some animals, such as mice and voles, are nocturnal, not because they can see better at night, but because they feel safer and, to a greater extent, these animals are hidden from predators. Hawks search for rodents and small mammals during the day and owls take over the hunt at night.

Most daytime animals, including humans, do not have this tapetum lucidum, which is why our night vision is mediocre compared to nocturnal animals. Our night vision increases when we are in an area of total darkness. After about 30 minutes in the dark, a person has optimal night vision.

However, when a flashlight is turned on or a cigarette is lit, our night vision becomes limited. The US military states that it takes 30 minutes for someone to regain their best night vision.

When a flash is used to take a photo, the eyes of the person in the photo may appear red. Because we humans do not have a tapetum in our eyes, this red eye occurs when the flash illuminates the blood vessels at the back of our eyes. If the source of the flash is anything other than a camera flash, there will be no red-eye.

I’m sure you’ve all heard someone say it “they had the deer in the headlights” Look. This describes a person who is so stunned that he can no longer move, with his eyes wide open and unable to find words.

A light shined on a deer’s eyes at night will cause the deer to become confused and the images to become blurry. Often the deer just stands there. However, if the deer runs away after the light shines on its eyes, night vision returns immediately.

It is illegal to hunt deer at night with lights. In Pennsylvania we call this jacklighting. This term has its origins in colonial times, when people went deer hunting at night. Since there were no flashlights, the hunters lit baskets of pine knots, which burned brighter and longer than other pine knots.

As a conservationist, I have spent many nights searching areas for spotlights crossing the sky. Most of the time the flashes in the sky were simply families looking for deer. However, every now and then I caught a jacklighter and an arrest was made.

Animals aren’t the only creatures that have eye shine. There are fish – especially walleye – that have a white eye shine. Some species of spiders have eye shine, but this eye shine is not the result of tapetum lucidum.

Humans have imitated this nocturnal eye glow found in animals by creating reflectors that shine when light is thrown on them, to help us drive safely at night. Just one of the many things we have copied from wild animals.

Bill Bower is a retired Pennsylvania Game Commission Wildlife Officer. Read his blog and listen to his podcasts about the outdoors at www.onemaningreen.com.