By chance, I looked out the window as an enormous bullfrog hopped across the lawn. He made two long leaps then sat very still. As moments turned to minutes I realized that I probably wouldn’t have seen him if he hadn’t been leaping at the precise second I looked outside. Sitting still he was hard to spot. Finally, the bullfrog made a couple more leaps, then sat still again. It occurred to me that the bullfrog was heading north, away from our pond. There are no ponds in that direction. Frogs need ponds to survive, especially in winter when they burrow into the muddy bottom. Where was this frog going and why?
Such questions got me thinking about winter survival strategies of various animals.
Beavers, also pond denizens, use a different strategy. They build houses, or lodges, out of piles of tree branches. They also store green sticks by driving them into the bottom mud and thus have protected access to their food supply.
The black and red ants also build houses. These look like mounds of short bits of straw and other vegetation. These nests can be several feet wide and a couple of feet high! Ants overwinter in the core of these nests. The nests stay amazingly dry inside.
One could argue that honey bees also live in a house (usually supplied by people). They store honey in the honeycomb. The bees build their honeycomb on embossed sheets of beeswax supplied by the beekeeper. They can also can build walls of honeycomb inside structures such as hollow trees. Bees actually heat their hives by shivering, and survive winter by forming dense clusters around the queen. As well as shivering, the bees continuously circulate from inside the cluster to the outer edges and back.
Pine bark beetles survive winter as larvae. Their larvae live under the bark and constantly eat the soft wood. The beetle larvae generate alcohols in their bodies that act as anti-freeze which allow them to survive cold temperatures.
Bears have to eat a lot, to store the fat they need to survive winter. They minimize their energy use by hibernating, or sleeping most of the time. Bears are renowned for living in caves, but caves are not always available. Bears will also overwinter in hollows under stumps, or may dig holes into the ground, creating dens.
Under the heading of overwinter strategies, the most obvious one that comes to mind is the highly visible migration of birds south. It is very common in late September or early October to see and hear large flocks of song birds assembling and preparing for migration. On days with northwest winds are blowing, you might hear the honking of geese in the sky, and observe their classic V-formations, flying south to places such as California or Mexico.
I suppose you could say that people do all of these! Mostly we live in houses that are heated. But we also build mobile houses (motorhomes) so that we can migrate south to places like California or Mexico. At which place we sleep a lot and eat a lot. And emulating pine beetles we may build up our alcohol content, to help thwart the cold weather! I just hopewe don’t make the same mistake as the bullfrog, and that we go north, instead of south!