Winter is the time for thick sweaters, hot beverages and snuggling up with a good book by the fireplace. Preparing to spend time outdoors we bundle up in snowpants, warm coats, hats and gloves. Indoors we run our furnaces throughout the coldest months. Staying warm for humans typically means altering our exterior. But what about the wild animals that spend all of their days outdoors. How do they stay warm without the benefit of human comforts? This blog explores the different methods of adaptation to the change of seasons in some of those wild warriors that spend their winters here in the southern tier.
White-tailed Deer
The most common ungulate in the US, the White-tailed deer is native to North America, southern Canada and portions of Central and South America. In the eastern states, deer live their entire lives in the same location. As the air grows cold, those in the north replace their summer fur with a longer hair and a thick undercoat. These browsers will continue to feed on twigs and bark through the winter but at a slower pace. Instead they build up fat stores, reduce their movement, thereby lowering their metabolism, and bed down through the night to conserve energy. This image photographed by Stan Edwards is a white-tailed doe sporting her winter coat.
Additional winter White-tailed doe images photographed by Gina Vaughan (left) and Kelly Frederick Sweet (right).
Eastern Gray Squirrel
Have you ever seen a squirrel in your yard and thought it looked fat, as though it had been eating too much? In fact, it is likely the squirrel has just been preparing for winter. Similar to deer, squirrels in winter climates plan for winter months by fattening up. These reserves help carry them through the long, cold months when food sources are scarce. Another method employed by these small rodents is food caching. During the warmer months squirrels collect nuts and seeds, dig holes and plant them, relying on their excellent spatial memory and sense of smell to relocate their caches during winter. Unrecovered caches often germinate which is why squirrels are responsible for propagating trees, shrubs or other vegetation.
Muskrat
Much like the deer and squirrels, muskrats are also active throughout winter. These semi-aquatic rodents are typically found in marshes, ponds and wetlands. With two layers of dense fur, the outer of which is waterproof, muskrats are well insulated. Their inability to stockpile food, or build up fat reserves forces these omnivorous rodents to hunt for vegetation, small mammals or aquatic invertebrates throughout the seasons. Bill Baburchak's image below is one of a growing population of muskrats at Brick Pond.
Muskrats burrow into banks or dams, often contributing to structure degradation. They may also build lodges with a combination of vegetation and mud. Example of a muskrat lodge photographed at Brick Pond by Teri Franzen.
Snowy Owl
With a population decline of as much as 40% in the last three generations, the Snowy Owl was classified in late 2017 as “Vulnerable” by the IUCN. We wouldn’t know this based on the increasing frequency and strength of winter irruptions that have occurred in the US since 2013. In the past few years, likely due to fluctuations in lemming population in the arctic, we see an increasingly larger number of Snowies wintering in the US. Snowy Owls are physically hardy enough to remain in the Arctic Tundra where they breed. However, when lemming populations plummet, the younger owls find it necessary to move further south during winter months in search of small rodents. These owls like wide open spaces allowing them far views. Because they have traveled far in search of food, they often arrive weary and hungry. If you see one, it is important to view from a respectful distance to avoid influencing their behaviors and further adding to their exhaustion. This owl was photographed, at a safe distance, by Kelly Frederick Sweet in Pennsylvania.
Great Blue Heron
Many Great Blue Herons that breed in the northern states remain in the area throughout winter. Requiring only water and a food source, these hardy waders will often travel only as far as the next open lake, river or pond. This image was photographed by Gina Vaughan one wintry march at the Owego Confluence.
Songbirds
Non-migrating songbirds are commonly attracted to yard feeders during the winter months.
Birds stay warm by fluffing up and trapping heat between their feathers and benefit from their rete mirabile adaptation which is a complex of arteries lying close together. By tucking one leg near their bodies, birds are able to transfer heat to the extended leg. Both behaviors are demonstrated in this image of a White-throated Sparrow photographed by Teri Franzen.
Northern Cardinal
Northern Cardinals are non-migratory songbirds that spend their lives in the same location. This female cardinal showing her chops in the harsh winter wind was photographed by Diana Meyn in January 2019.
White-breasted Nuthatch
White-breasted Nuthatches typically prey on insects during the warmer months. During winter they join foraging flocks that are often led by Chickadees. This nuthatch was photographed by Cheryl Utter in her backyard.
Black-capped Chickadee
Black-capped chickadees are small, gregarious songbirds that join small flocks during the winter months. Similar to squirrels, they are known for caching seed. This chickadee was photographed mid-hop by Cheryl Utter.
Dark-eyed Junco
Typically ground-dwellers, Dark-eyed Juncos nest in forests and can be found wintering in suburban back yards. The following dark-eyed juncos bravely withstanding cold, snow and gusty winds were photographed by Gina Vaughan.
Resource Links
White-tailed Deer
http://wiredtohunt.com/2013/01/31/whitetail-winter-how-deer-survive-the-arctic-freeze/
https://now.tufts.edu/articles/how-do-deer-survive-harsh-winter-weather
https://bigdeerblog.com/?p=4682
https://www.outdoorlife.com/blogs/big-buck-zone/2013/02/do-whitetails-migrate-washington-study-aims-pattern-deer-movement
About the Author
An active member of the Waterman Center board of directors, Teri Franzen is a professional wildlife photographer, videographer, writer, naturalist and conservationist working to promote natural history awareness through photography education. With a strong emphasis on ethics, Teri is passionate about observing and photographing wildlife on its terms, wild, unaltered and undisturbed.