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Can Weather Affect Migration?
April 15, 2019
Hi,

Earth shine.

Last week Monday there were a few thin clouds that were lurking about.

The clouds show on the camera, but not here.

Oh well.

I wanted to see if they would come through the picture with the moonshine.

They are there, I'm not sure if you can see them, however.

Spring.

This week it was one step forward and two, maybe Three giant steps back.

From 70 degrees (F.) to a couple of snow events.

Thankfully we didn't get slammed like parts of the Northern Plains area did.

30 inches of snow in April?

I would cry.

The Red Maple is in Bloom right now, I showed the buds from the same tree 2-3 weeks ago.

All trees blossom, some species are even so picky as to go male plant, and a separate female plant.

They are known as Dioecious plants.

Ginkgo Trees, and Holly are two species that require one of each to reproduce.

Monoecious plants have male flowers and female flowers in separate structures on the same plant.

Think Squashes, corn and so on.

Most plants are Hermaphroditic.

A plant that produces both male and female reproduction systems and in the same flower.

Wow, I still remember that stuff after all these years.

Backyard bird patterns have changed, yet there is still plenty of activity.

Fewer birds visit the feeders these days.

A crescendo of bird songs fill the air from dawn to dusk.

Goldfinches are pretty much back to full color.

A Mourning dove gathers nesting material.

The Male robin is listening for food (worms), not looking for something as one might think.

Juncos remain, but most are females these days.

Blue Jays, Nuthatches, Woodpeckers, Titmice, Cardinals, Robins, and more.

Yes, the air is filled with song and movement.

I love nature.

Backyard bird patterns have changed, yet there is still plenty of activity.

A crescendo of bird songs fill the air from dawn to dusk.

Goldfinches are pretty much back to full color.

A Mourning dove gathers nesting material.

The Male robin is listening for food (worms), not looking for something as one might think.

Juncos remain, but most are females these days.

Blue Jays, Nuthatches, Woodpeckers, Titmice, Cardinals, Robins, and more.

Yes, the air is filled with song and movement.

I love nature.

Brandy and Snickers are being treated for Hookworm.

The Animal Hospital, suggests that Brandy came home with them and passed things on to Snickers.

Bloody and runny stools are not good.

Snickers has been normal, must take time for incubation.

I'm not sure if the cats can get it from the dogs, nothing was said about that.

The girls are finally getting along for the most part.

Brandy wants to play all the time.

Snickers has to stop things once in a while.

No matter, fur kids are a hoot.

To bad they don't come potty trained.

This week I conclude Bird Migration.

There truly is much to learn and understand,

I hope to share a few basics about weather and Migration.

Enjoy.

What external factors prepare birds to migrate?

Last week I mentioned how the length of day and intensity of the sun stimulates the pituitary gland and this accelerates the growth of the gonads and all other metabolic processes, including the development of the thyroid, to prepare the bird for migration.

What external factors affect time of migration?

So, if pituitary functions and variations in day length were the only factors, migration would occur regularly every year.

Such a lack of flexibility could be catastrophic for migrants because of variations in biological and meteorological conditions.

Environmental factors such as weather, arrival of spring, flowering, foliage, insect hatching and availability of food vary from year to year.

The pituitary prepares the bird for migration.

The proper ecological conditions are necessary to trigger it.

Birds can be exhausted and emaciated by the time they reach stopping areas.

They gorge themselves to replenish their fat reserves before preparing for the next leg of the flight.

Does the temperature affect migration?

Weather and temperature are very important-the first cold front of the fall usually brings with it flocks of migrating geese.

Many birds follow a temperature gradient as they return to nest in the spring.

Birds vary in sensitivity toward temperature and other environmental conditions.

Some years, in the South, up here in the North and parts in between, migrating birds are caught in poor weather conditions.

A freak snowstorm.

Winds and heavy rain may blow in.

Cold temperatures that keep the insects from flying.

All conditions that have killed off thousands of birds on any given year.

Often the yearlings and inexperienced males take off before they should, (experience dictates to slow down and live another day).

Many species of birds depend on the weather conditions to initiate migration (both spring and fall).

Once migration begins the patterns of their flight depend on temperature and barometric pressure.

Other birds such as swifts, swallows and orioles are less weather dependent and the dates of their departure and arrival occur with regularity each year.

The swallows at Capistrano, for example.

How does the weather affect migration?

Weather is one of the chief external influences on migration.

Cool air masses moving south in the fall can trigger migratory flight.

Cool air brings high pressure, low or falling temperatures and winds moving in the direction of flight and clear skies.

If the cool air meets warmer air, clouds, precipitation and fog may result.

Fog, especially, causes birds to descend to the ground and cease migration.

Sudden changes in the weather can be disastrous for birds.

In the spring a warm, moist mass of air (low pressure with higher or rising temperatures) moving north over the Gulf of Mexico can start a wave of migrating birds to move northward from the American Tropics or southern United States.

A southward moving cold front meeting such a warm air mass can result in heavy rains and high winds.

This can stop migration immediately or within 24 hours.

These spring 'groundings' of migrants may occur when the migrating birds literally fall into sheltered areas seeking food and refuge. This can be disastrous if the migrants are forced down into the ocean drowning thousands of birds.

Resumption of southerly winds and rising temperatures starts migration northward again.

Next Sunday (April 21) is Resurrection Sunday.

Every year I try to send out a message where I can hopefully 'Glorify God'.

Well, it is time to fly.

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

God Bless.

“All endings are also beginnings;

we just don't know it at the time.”

Mitch Albom(B - 1958)

American author, journalist,

screenwriter, dramatist,

radio and television broadcaster.

I spent my teen and young adult years reading Mitch's column in the Detroit Free Press.

He is a very talented writer (Tuesdays With Morrie).

His quote does ring true.

God's word.

"Praise be to the God and Father of our Lord Jesus Christ! In his great mercy he has given us new birth into a living hope through the resurrection of Jesus Christ from the dead".

1 Peter 1:3

"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



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Gardening For Wildlife.


























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