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Bird Lungs, How Birds Breathe
October 02, 2017
Welcome to October.
(Honey Bee on Aster, notice the pollen sack.)
It is finally beginning to feel a bit like Fall around here.
At least temperature wise that is.
We did make Lake Michigan one last time this past Tuesday.
The lake water was the warmest
Record breaking heat will do that.
The warmth of the sun on these cooler days feels good on the face.
The fur kids find a sunny spot in the house and take a nap.
The bees find the flowers (Asters) that are in the sun and have a pollen fest.
As the sun moves across the sky, the bees drift to find the sun once again.
I Love Nature.
A late season Monarch gets into the nectaring as well, pictures show the butterfly on the Asters, and on a waning Phlox.
The heat and a couple of busy days kept us away from 'ARTPRIZE' this past week, we will see if we can make it this week.
We haven't missed a year up till now.
Yolanda and her gang from Hope has been to some art already and are scheduled again this week.
Poor Akita, Had her teeth cleaned last Monday, she came home with five less teeth.
Kind of makes me feel bad, but the Vet says it is quite common in small dogs.
Pain pills and soft food have helped.
By weeks end, she was her diva self, once again.
(A recently fledged Norther Cardinal waiting to be fed.)
First of the month my friend.
Time to clean ans sanitize feeders and water sources.
Might as well clean out any nest boxes (bird houses), that need it.
Birds are really special creatures.
At least they are to me.
As long as I can recall, birds have held a special place in my life.
I'm not sure if it is the freedom of flight or the ability to go just about anywhere, or simply the colors.
No matter, birds are indeed special and in many ways unique.
You and I know they are the only creatures with feathers.
We know that with all the similarities with birds as a whole, there are also many, many differences among species.
From feeding habits and what they feed on, to nesting, migrations and where they live.
With all of this to attract us to them, and to attract them to our yards,'Nature'has also equipped with some unique features besides having feathers.
How Birds Breathe:
Birds have lungs and air sacs, which direct air through the lungs in a one-way air flow. This one way air flow lets birds maintain a high metabolic rate.
They have lungs and tiny nostrils at the top of their beaks, used for breathing.
This is the plain and simple answer.
Like us, birds need to breathe air in and out of their lungs in order to fulfill the cycle of bringing oxygen into the body to be used in metabolism and also to take the waste CO2 away from the body.
However, unlike us, when a bird breathes the air does not go simply in and out of the lungs in a simple u-shaped path.
Instead birds have a number of large extensions called 'air sacs' and hollow (pneumatized) bones all interconnected to their lungs.
These allow the air to flow around in a grand circle meaning this,
Birds can have fresh oxygen rich air in their lungs all the time.
Also unlike us mammals, a bird's breathing is not driven into and out of the lungs by means of a diaphragm.
In birds, breathing is controlled by muscular contractions of the rib cage that reduce or increase the overall size of the body cavity and thus force air out of the various air sacs.
Air is breathed in through two nostrils situated at the base of the bill (except in Kiwis where they are at the tip of the bill and gannets where nostrils have become redundant and breathing is through the mouth).
The air enters the 'trachea' then passes down the throat until it reaches the syrinx (a bird's vocal chords).
Here the trachea divides into two 'bronchi' before passing through the lungs.
The freshly inhaled air goes first, not to the lungs, but to the abdominal air sacs.
Yes, air sacs.
These are the largest and most important of a bird's air sacs.
Some of this inhaled air goes to the posterior air sacs also.
, their destination.
When the bird breathes out this air moves from these air sacs into the lungs.
When the bird breathes in again, this air moves from the lungs to the interclavicular, thoracic and anterior air sacs.
When the bird breathes out a second time the air passes up the bronchus and out of the bird's system.
It takes two breaths and not one for air to pass in and out of a bird's respiratory system.
Also important to note is the fact that air passes right through the lungs, this allows for an almost continuous flow of air over the 'alveoli' and for a greater exchange rate in gases.
This exchange rate is also enhanced by the fact that bird alveoli are 10 to 100 times smaller than ours giving a far greater surface area per volume for gaseous exchange to take place.
Unidirectional flow means that air moving through bird lungs is largely fresh air & has a higher oxygen content.
In contrast, air flow is 'bidirectional' in mammals, moving back and forth into and out of the lungs.
As a result, air coming into a mammal's lungs is mixed with 'old' air (air that has been in the lungs for a while) & this 'mixed air' has less oxygen.
With less oxygen, other mammals become winded and fatigued.
(I'm winded and fatigued by walking a couple of flights of stairs.)
This plays a vital roll in migration.
In bird lungs, more oxygen is available to diffuse into the blood at a constant rate which in turn, keeps a bird from fatigue and from running out of breathe.
Think of the diminutive Ruby-throated hummingbird?
These jewels fly non stop, up to 500 miles across the Gulf f Mexico, to reach their wintering grounds.
Some Snow geese will fly non stop, from the Arctic, to the southern States of America, and make the trip non stop.
Well fed and full of energy, birds can fly a long distance, only to stop for food, sleep and their destination.
500 miles, non stop.
Creation is amazing.
Well, it is time to fly for now.
Before I go, here is your positive thought for the week.
"Even if it's a little thing, do something for those who need help, something for which you get no pay but the privilege of doing it".
We are privileged to help others.
Have you ever looked at it from that angle?
For I know the plans I have for you," declares the LORD, "plans to prosper you and not to harm you, plans to give you hope and a future.
"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.
Your friend indeed,
Better yet, have them sign up so they can receive their own letters.
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