How Wildlife Survive Winter

How Wildlife Survive Winter

It’s hard to imagine spending the entire winter outside. As humans, we’re lucky we can keep warm indoors. Wildlife must either migrate, adapt or enter a state known as dormancy during the cold winter months.

Dormancy is when an organism’s metabolism slows down for a period of time. It’s triggered by environmental conditions like cold weather, reduced light and lack of food. Normal activities like running, eating and breathing use up large amounts of energy which are hard to recover in winter. It’s a useful strategy to conserve energy.

There are several types of animal dormancy including diapause, brumation and hibernation.

Diapause 

Diapause is a type of dormancy used by insects and other arthropods like spiders. The ability to enter diapause allows insects to temporarily stop their development until environmental conditions improve. This is often in the spring or summer. Diapause can happen at any time during their life cycle, however, it’s most common during the pupa life stage such as moths in their cocoon. When the weather gets cold, these animals seek shelter in a variety of places like under logs, bark, or soil.

Cross orbweaver. Photo credit: Jon Clayton

Brumation  

Brumation is a type of dormancy used by cold-blooded animals like reptiles and amphibians. They depend on their environment to regulate their body temperature. When temperatures and daylight hours drop, there is less heat in their environment. As a result, they must slow down and seek refuge in areas that remain ice-free to prevent their bodies from freezing. They move into underground crevices, deeper underwater or bury themselves in mud.

Animals in brumation generally do not eat, but on warmer days they may wake up to move or drink water. In the Credit River Watershed, this includes species like the eastern garter snake and northern map turtle.

Eastern garter snake mating ball. Photo credit: Sara Labrie

Hibernation 

The word hibernation is often used to refer to any animal that goes dormant during the winter. However, this type of dormancy only applies to warm-blooded animals. They can control their internal temperatures using their energy reserves. This is why you often see mammals fattening up or storing food in the fall. It’s so they have enough energy to get through the winter. They will seek refuge in areas like dens or burrows.

Hibernating mammals include true hibernators and light hibernators. True hibernators, like woodchucks, enter deep sleep and have a very low body temperature, a little bit above freezing. In contrast, light hibernators have a higher body temperature and can periodically wake up on warmer days to move or eat, including racoons, and eastern chipmunks.

Raccoon. Photo credit: Jon Clayton

Learn more about the animals in the Credit River Watershed.

By CVC’s Christina Kovacs, Specialist, Natural Heritage Management

5 Comment

Leave a Comment

Data and information released from Credit Valley Conservation (CVC) are provided on an 'AS IS' basis, without warranty of any kind, including without limitation the warranties of merchantability, fitness for a particular purpose and non-infringement.

Availability of this data and information does not constitute scientific publication. Data and/or information may contain errors or be incomplete. CVC and its employees make no representation or warranty, express or implied, including without limitation any warranties of merchantability or fitness for a particular purpose or warranties as to the identity or ownership of data or information, the quality, accuracy or completeness of data or information, or that the use of such data or information will not infringe any patent, intellectual property or proprietary rights of any party. CVC shall not be liable for any claim for any loss, harm, illness or other damage or injury arising from access to or use of data or information, including without limitation any direct, indirect, incidental, exemplary, special or consequential damages, even if advised of the possibility of such damages.

In accordance with scientific standards, appropriate acknowledgment of CVC should be made in any publications or other disclosures concerning data or information made available by CVC.
DATA DISCLAIMER