Subnivium Ecosystem Harbors Life

Subnivium Ecosystem Harbors Life

We humans don’t always like the winter snow for its inconvenience and sometimes safety threat. For many animals, the snow-cover makes winter the best time of year. Scientists who study life in this seasonal microenvironment under the snow call it the subnivium ecosystem. It allows many species of plants and animals to exist that could not survive without snow.

The first scientific writings about the subnivium world were circulated by a lepidopterist (a scientist who studies butterflies) named Vladimir Nabokov. Nabokov was investigating butterflies whose caterpillars eat plants known as blue lupines. These butterflies lay their eggs on the stems of the lupines a few inches above the ground. When snow covers the area, the eggs are protected from the very low temperatures of the mountains where the butterflies live. Scientists conducted a study of those same butterflies in 2019 when there was a significant decrease in the snow cover. They found a 43% decrease in the number of butterflies produced.

This is just one example of life in the subnivium ecosystem. Ruffed grouse burrow into the snow at night and stay in an igloo-like area that can be 50 degrees warmer than the outside air. In wintertime, a surprising number of animals live in the warmer subnivium ecosystem. Wolverines, martens, voles, mice, shrews, red squirrels, and even bears take advantage of heavy snow cover. The protection of snow allows abundant life at high elevations and in polar areas.

Every part of Earth is home to living things because of the design of the animals and plants and the design of water that gives snow thermodynamic properties. It is easy to overlook the statement God made to Job about “the treasures of the snow” (Job 38:22). The simplicity of those words describes a whole world of life in the subnivium ecosystem and the treasure of water stored on snow-covered mountains. The treasure house of snow speaks of the intelligence built into every corner of creation.

— John N. Clayton © 2021

Data from National Wildlife magazine, February-March 2021.

Shivering in the Cold

Shivering in the Cold
As I write this on January 21, my outdoor thermometer says that the temperature here in Michigan is -5 degrees Fahrenheit. I just graded a correspondence course from a young lady who lives in Tennessee. She asked, “How can the squirrels I see outside live when it is so cold here, and not even shiver?” It was 35 degrees Fahrenheit where she lives. Why don’t we see squirrels and other animals shivering in the cold?

Recently an atheist said that if God did exist, He wouldn’t make incredibly cold places like Alaska. In his mind, God is just too cruel to believe in. He would rather have the whole planet be like where he lives in central Florida.

There are so many problems with that view it would take much more space to discuss them all. The fact is that many animals are designed for the cold, right on down to making their bodies not feel it. The February/March 2019 issue of National Wildlife (page 8) has an interesting discussion about species of animals that have cold-sensing nerve cells that don’t feel temperatures below 68 degrees F. This allows an animal’s body temperature to drop for long periods so they can hibernate. They do not experience the cold that would keep them awake. Animals that don’t hibernate can survive and be active in temperatures as low as 35 degrees F without feeling the cold, and they can do so for up to nine months.

There are many benefits of animal hibernation both for them and for the ecosystems in which they live. God is sensitive to the problems produced by very cold conditions or even uncomfortable temperatures for humans. He has designed not only the conditions but also the physiological makeup of the living things that exist within those systems so they won’t be left shivering in the cold.
–John N. Clayton © 2019

Cormorants Find Fish in Muddy Waters

Cormorants Find Fish in Muddy Waters
Several years ago a flock of cormorants arrived on the St. Joseph River near our home. The river was close to flood stage. The water was so muddy that you couldn’t see the bottom even if the water had been only an inch deep. Those birds demonstrated that cormorants find fish in muddy waters.

The birds landed in a large tree on an island in the middle of the river. Very soon after they landed, one took off and dove into the river. A minute or so later it came to the surface with a fish in its beak. For the rest of the day, we saw these fishing birds dive and catch fish, sometimes staying under water for a very long time. I wondered how they could do that because sight in the water was non-existent.

In the October/November 2017, issue of National Wildlife (page 8), there is an article explaining how cormorants and other fish-eating birds manage when the water is so loaded with mud that they can’t see. Scientists at the University of Southern Denmark have studied the hearing of the great cormorant. They discovered that this seabird has a specialized sense of hearing tuned to a very narrow frequency range. The frequency is the same as the sound produced by herring and sculpin fish as they swim in the water. Those fish are the primary prey of the cormorant and sculpin live on the bottom of water bodies where it is dark, and the water is often dirty.

There are over 800 species of birds that find their food underwater. Since these cormorants find fish in muddy waters, the scientists on this project predict that other aquatic birds also use specialized hearing to catch fish. We see this as another design that God gave these creatures for survival.
–John N. Clayton © 2017