Winter is Coming: How Animals Prep for Winter in the Wild

 

Winter is Coming: How Animals Prep for Winter in the Wild

Written by Kristine Manganelli (Somerset County 4-H Coordinator)

Eastern Gray Squirrel

Eastern Gray Squirrel

As we move further into fall and approach winter, you may notice animals in a scurry on the ground. Eventually, you will also notice fewer animals out and about. This is because winter is a risky time for warm-blooded animals. The freezing temperatures and scarcity of food leaves many species vulnerable during this season. But as nature is full of incredible phenomenon, animals have developed techniques and adaptations to survive.

In a recent post we discussed the process of deciduous trees shedding leaves in autumn ahead of the winter season. They do this to be ready for dormancy, the state of slowing or suspending physical functions. As winter approaches, the tree must prepare for freezing temperatures as they cannot take frozen water in through their roots. During the rest of the year, water is evaporated from the leaves, so shedding them allows the tree to preserve water for the season.

But what about the rest of the critters in the forest? How do they survive the winter when they cannot put on mittens or scarves, and cannot sit in front of a fire or sleep in a heated house? Below are examples of winter survival tactics.

Hoarding Food- Animals that do not leave the area will begin to create food caches (or stockpiles of food) in the months and weeks ahead of winter to be used when resources are scarce. Squirrels and chipmunks can be seen gathering acorns, nuts, and mushrooms before hiding or burying them in a process called “scattered hoarding”. They spread their stashes to avoid thievery, and a single squirrel may have hundreds or even thousands of hiding spots. They have even been observed attempting to deceive others by digging fake holes.

Many mammals will eat as much as they can to store fat reserves that will be used later, as well as add a layer of insulation for warmth. As winter approaches, some species like bears enter hyperphagia, a biological need to eat and drink as much as possible in order to gain weight for the long winter. Starting in the fall, groundhogs may eat up to one pound of food per day!

Changing Appearance- Many animals such as rabbits, foxes, and white-tailed deer have adapted by growing a thicker winter coat, or changing color to blend in with the changing winter landscape. Their brown fur will become gray to match the woods when the green fades away and they become barren and snow covered. Despite this extra layer of fur, white-tailed deer may lose up to 30% of their body weight in the winter because of the extra energy used to keep warm.

Black Bear

Black Bear

Hibernation or Dormancy - An excellent way to survive the winter is to avoid it all together. Some animals like bears will spend a majority of their time in the winter sleeping in a tight ball to retain warmth within their nest or den. They will occasionally come out to gather food or enjoy a rare warm day. This allows them to maintain survivable temperatures and use less energy, ultimately requiring less food.

Other animals such as bats and groundhogs go into a deeper rest called hibernation. During hibernation, an animal slows down its body functions for months, and won’t return to normal until spring. During this time, the animal enters a deep sleep where their breathing rate, heart rate, and body temperature will drop significantly. This state allows them to conserve so much energy that they do not need to eat.

Resistance or Tolerance to the Cold - Animals such as mice, moles, and foxes remain mostly active during the winter when they may spend most of their time in “subnivean tunnels” or a layer between the ground and the snowpack. In this space, it actually stays at 32 degrees or above, even if temperatures plunge.

Migration - Another way animals avoid winter is to migrate (or move from one location to another) to an area with a warmer climate where they won’t have to struggle to stay warm, and the food supply remains at normal levels. You may notice birds such as geese flying through our area, making their way south for this very reason. The familiar “V” pattern that they fly in actually serves a purpose as each bird flies slightly lower than the one in front of it. This strategy reduces wind resistance which helps them conserve energy.

Some creatures travel great distances to escape winter; you may remember our blog post about hummingbirds and monarch butterflies migrating thousands of miles to Mexico! But migration is not always such a long journey, some animals will simply migrate from a higher altitude on a mountain, to the base of the mountain, where temperatures and weather are more mild.

Get Outside

During the winter season it is more challenging for animals to find fresh food and water. Here are 3 easy ways to help make life easier for wildlife this winter.

  • Feed the birds
    Put out bird seed and make your own bird feeder using these directions.

  • Break the ice
    Put out fresh water in bird baths and make sure any water in your yard is accessible for animals to drink by breaking or melting any ice that forms.

  • Let your garden go wild
    Leave your garden undisturbed – piles of leaves can make the perfect habitat for animals and insects to hide, rest and hibernate.
    Save the task of cleaning out your garden until early spring.

Sources:

 
Somerset County 4-H