Observing Deer Around the Year: White-tailed Deer Phenology
By Mary Shaw
Broadcast 11.10 & 11.13.2021

White-tailed deer fawns. Photo by Larry Smith, CC 2.0.




I am an explorer at heart. I love wandering in a forest, over a mountain ridge, around just this next bend in the trail to see what’s there, to find a new experience. But following the same trail regularly, visiting the same favorite places feeds my sense of adventure equally. There is always something new to experience, even in the places I have visited hundreds of times.

I especially appreciate the chance to observe the same organism or geological feature repeatedly over time. The spring waterfall transformed from roaring cataclysm to gentle trickle over the summer, the grove of larches at the opening of my trail budding and glowing beautiful shades of green, then yellow and gold, then bare-sticked, allowing the sun to shine on the trail. I enjoy looking for what is new each visit and guessing the reasons for what I see. Then I check the field guide or internet or nature app to find out more.

I recently learned that my investigation of these changes and why they happen has a name: phenology. Phenology is the study of “cyclic and seasonal natural phenomena, especially in relation to climate and plant and animal life,” according to the Oxford English Dictionary.

I have the greatest opportunity to observe the phenology of the ever-present white-tailed deer. White-tailed deer are delightful to watch as they graze in the meadow in spring and summer, gather around a fallen spruce to munch on sweet lichens, or leap over fallen logs, their white fluffy tails waving like flags. In the winter they congregate in groups. This helps them stay warm in the cold weather and also makes it easier to move around with many hooves stomping down the snow.

In winter, their diet consists of mostly woody plants. By spring, the does have dispersed from their groups and graze alone on lush grasses and forbs, restoring some fat lost over winter to nurture their gestating fawns. In late June, watching the meadow below my house, I see a fawn peek out of the long grass on spindly legs, covered with a beautiful spotted coat. It meets its mother and nurses for a few minutes before returning to its hiding place. Fawns hide all day in the brush or grass for the first two weeks of life until they are strong enough to flee predators. While it is hiding, its mother stays away so she won’t reveal her fawn’s location. I was surprised to learn that the doe goes so far as to eat her fawn’s feces to further prevent its detection.

In high summer I watch the fawns emerge from the grass, reveling in their ability to run and leap. Soon their spots begin to fade, and by late September, they have disappeared. As autumn progresses, all the deer lose their tan summer color for a denser, grayish coat with thick fur and hollow guard hairs that will keep them warm and offer camouflage in the gray and white forest floor of the coming winter. Autumn is also the time I am most likely to spot a buck with antlers as they move through the forest seeking a receptive doe. The doe avoids the buck and leads him in chases for a day or so before allowing him to mate. I was lucky to capture a couple of such chases on a trail camera last year.

Observing these cyclical changes in appearance and behavior makes me feel that I know this animal, plant, stream—this place. It connects me to my environment in a visceral way. The fact that the arrangement of spots on the fawn’s beautiful red coat will be different tomorrow, never the same again, the transience of the experience, is what makes it so enchanting.

What changes have you noticed on your neighborhood walk or favorite hiking trail? Do you look for delicate white flowers on the serviceberry in your backyard because it bloomed about this time last year? Are you surprised and thrilled by the first Red-winged Blackbird’s song down by the pond in late March? If you anticipate these changes like I do, you find joy in discovering something new in familiar places and recognizing the fascinating nuances of phenology.


Every week since 1991, Field Notes has inquired about Montana’s natural history. Field Notes are written by naturalists, students, and listeners about the puzzle-tree bark, eagle talons, woolly aphids, and giant puffballs of Western, Central and Southwestern Montana and aired weekly on Montana Public Radio.

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