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How Birds Stay Warm
February 05, 2018

(Miss Penny doing a balancing act on Yolanda's chair.)

At the bottom is the puzzle Sophie helped me with last week.

The puzzle was surprisingly challenging, even with Sophie's help.

I will also post that picture, in case you missed it last week.

We enter the first full week of February (Already).

It is time to clean and sanitize feeders and water sources, if you can.

Often a quick spray with rubbing alcohol will do in a pinch.

Alcohol evaporates, and leaves no harmful residue, while killing off germs and cooties.

And here in the Great Lakes Region, winter has reappeared, and with a firm hand.

Birds are feeding at a fevered pitch, as snow fell most of the weekend.

Yes, after three January thaws, we are back in the deep freeze and a beautiful white landscape once again.

If it's going to be winter, I would rather have it white, not brown, gray, and ugly.

(Sophie and Snickers sleeping with Karen.)

Again, don't forget the upcoming

Great Backyard Bird Count.

It is February 16-19 this year.

Come on and help out.

Become an amateur scientist for a weekend.

Go to the above site and sign up.

February is also 'National Bird Feeding Month'.

Because natural supplies are at a premium this time of year, Congress has recognized the need for birds and the need for us to help our feathered friends.

While birds congregate at the feeders, in parks or elsewhere, it is a good time to participate in the GBBC.

Birds need our help with food to survive winter, as natural sources become less and less.

Here are some important ways that "Nature" helps birds to stay warm during the cold winter.

I write on this every so often, is it time for a refresher course, or maybe some new information?


You may know, I like to take evening walks.

Often the Fur kids (dogs), will join me.

But this real cold weather makes it difficult for them.

Not to mention the snow is too much for the little pooches to walk through.

Winter poses several challenges for our birds as well, especially when the temperatures dip, and dip some more.

We don't often think about, or wonder how our birds survive the colds nights.

You just know they do, or at least you hope they do.

Even those moments in the deep South, Desert regions or the Pacific coast where a cold snap, or several inches or feet of snow fall, can effect a bird population.

Winter brings extreme cold temperature, strong winds, driving snow and rain.

Nights seem to last forever.

14 - 16 hours of darkness, and in some locations more darkness than that.

That doesn't leave a whole lot of time for birds (and all wildlife), to forage and feed.

Not to mention a dwindling food source.

Yet, many birds must at least triple their normal intake to survive.

And do it in half the time.

Each winter we lose many of our feathered friends to the rigors of winter.

It's how "Nature" works.

Survival of the fittest.

Passing on the strongest genes.

Birds have many adaptations to survive the extremes of winter.

Some birds migrate.

Some adjust their diet habits.

Birds such as Chickadees and American goldfinches add feathers in preparation for winter.

Yes, the typical chickadee or goldfinch is covered with about 1,000 feathers during the summer.

By the time winter arrives, they have doubled that count to more than 2,000 feathers.

For a small bird, that can be some serious added bulk and weight.

During cold, windy or just a plain nasty day, birds will fluff up their feathers.

By doing this, they create dead air pockets, much like insulation or a double pain window.

This reduces the heat loss by up to 30%.

Extra feathers and fluffing isn't enough to make it through a cold winter day, yet alone the cold, long dark nights.

Nature provides additional help.

If you've been with me any length of time, you have read about blood circulation and bird legs.

Birds have a unique circulatory system in there legs to help them cope with cold temperatures.

Pay attention to this now.

Warm arterial blood from the birds interior, which is on its way to the bird's legs and feet, passes through a network of small passages that runs alongside the cold returning blood veins from the feet.

The network of vessels acts like a radiator and exchanges the heat from the out-going warm arterial blood to the cold venous blood.

By warming up the old blood, no heat is lost and the feet receive a constant supply of life sustaining blood.

This is also why water fowl can swim in near freezing water and not get cold.

In the summer, this works as a bit of an air conditioner.

A Side Note:

Because the blood doesn't warm up a bird's feet and because of the scales (no skin, no sweat or evaporation), birds don't freeze to metal poles or birdbaths.

I digress.

Fat, is another important winter weather survival adaption.

Fat acts as an insulator, in addition to an energy reserve.

During the day, birds eat to build up fat reserves.

On average, a bird can put on up to 15% to 20% of body weight in fat before it becomes to heavy to fly.

Now remember, days are shorter and cold.

Birds have to eat enough to survive the day as well as replenish the fat reserves.

The smaller he bird, the higher the metabolism (more energy burned).

Birds don't have brown fat, the kind we have.

Instead they have white fat.

White fat is a high-energy fuel used to power the bird's warming process.


Thermogenesis is a fancy name for shivering.

You can't really see it, but all birds shiver in the cold of winter.

From the largest of birds like eagles and water fowl to the smallest of birds, like hummingbirds.

They all shiver to maintain their core body temperature at about 106 to 109 degrees, depending on the species.

That is an amazing high temperature compared to the surrounding air temperatures.

This past week in some locations, that is more than a 150 degree difference.


Shivering produces heat five times their normal basel rate and can maintain a normal body temperature for six to eight hours at temperatures dropping to minus 70 degrees Fahrenheit.

Without shivering the bird's body temperature would quickly drop and the bird would become hypothermic.

I might add this, penguins only shiver if a patch of skin is showing, or there is some feather damage.

Penguins are a different sort.

At night, birds such as the little chickadee take shivering, or lack of one step further.

To conserve heat and energy, chickadees can lower their body temperature by interrupting their shivering.

These periods of inactivity allow the bird's body temperature to slowly cool, until it drops about 10 or 12 degrees.

At this point, the bird enters a state of unconsciousness called torpor.

Respiration and heart rate will also drop during this period.

Isn't Nature wonderful?


As morning nears, the periods of inactivity decrease until the bird is constantly shivering once again.

The body temperature is back in the normal range and the bird regains consciousness.

The results of this torpid state is an energy savings of up to 20% during a typical winter night. (much like you and me turning the thermostat down before we go to bed).

Conserving energy is very important when you consider how little fat a bird can store.

Based on a daily increase of body fat of 15% a typical chickadee has about 16 to 24 hours of fat or energy reserves to carry it through a winter night.

That my friend is why it is imperative that a bird gets out early in the morning and stays out late to find food regardless of the weather.

If it doesn't replenish its fat reserves every day, the bird will not have enough energy to make it through the next night and will die.

There was a time when the natural world provided food for most wildlife.

With the constant shrinking of habitat, winter protection and food supplies continue to shrink.

You can increase the odds for birds and some mammals by simply filling your feeders with their favorite food and offering suet.

Fresh water is important as well.

When birds are required to eat icy cold snow, it takes valuable energy to warm that snow as it passes through.

Next time you trudge out into the cold or even the warmth to fill your feeders, think of this...............

God has provided birds with some wonderful tools to survive, whether it is migration, blood circulation, change of diet, added feathers, or shivering.

Birds are truly a wonder for us to enjoy.

In one way, it is unfortunate that many birds now need our help to survive.

Yet look at the education and joy we get out of caring and feeding our birds.

Not to mention that feel good all over feeling we get.

Well, it's time to fly for now.

Before I go, here is your positive thought for the week.

God Bless.

“Reflect upon your present blessings,

of which every man has many

not on your past misfortunes,

of which all men have some.”

Charles Dickens

Reflect, don't dwell on the past.

The past can be a great teacher, if you allow it to be.

Now from the Bible.

“Forget the former things;

do not dwell on the past.

See, I am doing a new thing!

Now it springs up;

do you not perceive it?

I am making a way in the wilderness and streams in the wasteland".

Isaiah 43:18-19

"Treat the earth well:

It was not given to you by your parents,

It was loaned to you by your children.

We do not inherit the Earth from our ancestors,

We borrow it from our Children."

Ancient Indian Proverb.

A Blessed week to you .

Your friend indeed,

Ron Patterson

PS. If you enjoy these letters, please forward them to friends, family and co-workers.

Better yet, have them sign up so they can receive their own letters.

Gardening For Wildlife.

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