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Fall Migration Begins. Part 1
October 06, 2008
A cup of hot chocolate please, and save me a spot near the fireplace.
How fast the weather can change this time of year. The last week of September blessed us with temperatures in the upper 70's and low 80's.
This past week struggled to reach 60 degrees and I'm not sure if we managed that at all.
A 30 degree swing is a huge difference.
Sprinkle in some rain and high humidity and days become a chilly damp.
I suppose that is a down side of living near so many bodies of water.
Temperatures promise to be warmer this coming week.
Even with the chill and some cool nights, we still haven't had a killing frost yet.
Fall colors are slow to arrive this year (though there are some trees changing).
According to the local Meteorologists, fall colors in Michigan are running a couple of weeks behind because of the abundance of rain this summer and above normal temperatures we' had in September.
I've managed to get some fall clean up done.
Pulling weeds, transplanting, cutting back some perennials and removing diseased foliage.
Pulling up old veggie plants and of course, the "Honey do list" that never has an end to it.
"DO NOT" place diseased or fungus filled foliage in your compost piles.
Germs and bacteria can winter over and even multiply in your compost.
Be sure that all sick foliage is tossed.
The last thing you want is an influx of Blackspot, Powdery mildew or a Blight running rampet in your gardens.
There is so much to do this time of year, even if it means the end of a season.
With my new positive attitude (choke, cough) I have so much to look forward to yet with garden chores and wildlife that is all around.
Even when I'm digging or pulling, the air is filled with nature's sounds.
American robins are returning from their late summer hangouts.
With the bumper crop of American goldfinches, I am still blessed with the sights and sounds of offspring begging and seed heads bobbing from these true beauties of our yards.On a cool sunny afternoon this past week, I heard a familiar sound.
The sound of Sandhill cranes flying South.
Now I search the sky and found a flock of around 30 Cranes.
I wonder if they will stop over in Michigan, near Battle Creek at the Baker Sanctuary, where several thousand of these giants use as a safe place and staging area.
Michigan reader, if you get the chance this coming weekend, October 11th and 12th is the
No matter where you live, I urge you to take in the sights of the cranes.
One of these years, I hope to take in the spectical of an estemated 500,000 crane on the Platt River in Nebraska.
Now this is why you keep your flowers as long as possible and why you keep your hummers feeders stocked with fresh nectar water.
My resident hummers left September 25th, yet on October 1and 2. A strange hummingbird stopped by to feed and re-charge.
Daytime temperatures in the low 50's and nighttime temps. in the 30's.
Had I pulled up the salvia and taken the feeders down I never would've seen this tiny jewel.
The little bird had no reason to stop by my yard.
Except, I still had the welcome sign out and the free buffet was still stocked.
Now, if for some reason the "Closed for the Season" sign was up, I would have missed this opportunity.
What would happen to this hummingbird if my yard wasn't still open for business?
The hummer didn't look like it was starving, but my offerings just might get it over the hump and onto its next destination point.
This is October in Michigan.
You know it.
Hey, it's not the first year this has happened.
Hummingbirds like this one still have to make it to Mexico or at least Florida or the Gulf Coast.
Typically, birds that get a late start on heading South are this year's fledglings and from time to time an adult that has some mixed signals.
Because hummers don't flock, stage or follow parents, it happens that some birds don't get it right off the bat.
Now these hummers have to make it to their winter grounds. That means they still must cross several states to get there.
Will you be ready for them?
Cooler temperatures are also a good time to pet Bumble bees.
You may think I'm nuts or something, but it is possible and fun to do.
The bee will not attack you, they have better things to do.
Besides, the cool temperatures slow their body activities and are much easier to approach.
It is a nice task to help over come a fear and you can impress some friends or family members.
Approach slow and pet carefully.
If and when the Bumble lifts a front leg, it is letting you know she is getting agitated.
These non aggresive bees pose no threat unless you handle them step on them bare footed (as a child) or get to close to the nest.
I have yet to be attacked or stung for petting a Bumble.
Last week I started on "Fall Migration."
This week is "Part II" on Fall Migration.
It's now October.
Fall colors are slow in coming this year and I still have tomatoes.
One thing you can be sure of is Fall Migration.
Almost like a time clock.
When you see flocks of birds flying overhead in the fall, they usually are flying south toward their wintering grounds.
How far South they go depends on the type, or species of bird.
As you may know, some birds travel farther than others.
And this is the same species of bird.
For example, in some species females and young birds fly farther south than males.
Like Dark eyed juncos. Then there is the largest group of birds that we see during migrations.
these are known as or called "neotropical migrants."
They got this name because these species of birds migrate in the fall all the way to Mexico, Central America and South American countries, plus the Caribbean Islands.
Some of these birds will fly thousands of miles every fall and spring.
About 300 of the 650 bird species that nest in North America are neotropical migrants.
They include warblers, vireos, orioles, hummingbirds, swallows, swifts, shorebirds, and some birds of prey.
The neotropical migrants make up 50-70 percent of the bird species of deciduous forests and prairies in the central and eastern United States and Canada.
During migration, some birds lose as much as one fourth to one half of their entire body weight, so it is very important that they store up enough fat for energy.
Just think how much weight you would lose if you lost half of your body weight!
How smaller birds ever store enough to make these flights is still a wonder to scientists.
This is why it is so important for birds to gorge, so they can store up reserves.
Flocks may descend on your feeders, lawns and fields eating just about everything in sight.
Fats and energy supplies that take weeks to build up are burned up in a matter of days or in some cases, a day and night of non stop flight over a large body of water.
Birds can blacken the sky and become deafening as they flock to staging areas getting ready for the right time.
When the internal time clock says "It's Time" to go.
You may hear a lot about 'flyways' the notion being that birds move in defined corridors, like traffic down a road. Traditionally, birders talked about four main flyways: Pacific, Central, Mississippi and Atlantic.
Research indicates that this can be a misleading way to think about migration.
Instead, imagine broad bands, like test patterns on a television, or waves rippling down the continent.
Sure, geographic features can funnel birds, narrowing the bands.
Mountain chains like the Cascades and Sierra Nevada, Rockies, and the Appalachians present barriers and also opportunities.
Raptors coast the 'thermals' or (updrafts of warmer air) found along the ranges.
Hawk mountain in Pensilvania is a prime location to spot kettles of hawks.
A hawk kettle can be any amount of hawks whirling around.
Kettle counts can be a handful or tens of thousands.
South pointing peninsulas funnel birds in the Autumn, just as a North pointing peninsulas funnel them in Spring.
Birds moving down the coast find the land narrowing beneath them and they become concentrated at the peninsula's tip.
So, how do you find a good spot to observe the fall migration?
Three words: habitat, habitat, and habitat.
Birds will congregate where they can find something to eat and protection from predators.
If you know your birds even a little bit, you can find habitats where they congregate.
Birds tend to commence migration in large numbers only when they have a favorable tail wind.
In North America the winds north in spring and south in autumn are ideal to assist seasonal migrations.
Once started however, only very bad weather will stop them.
Many birds fly high when migrating because of prevailing winds at higher altitudes and also because the cold at these altitudes helps them disperse all the heat being generated by their flight muscles.
Many species of waterfowl fly at 18,000 feet and some higher.
Some must fly over the Himalayan Mountains, an altitude over 29,000 feet.
Not all birds from a summer breeding site overwinter at the same area.
What happens, come autumn, if a male bird meets a female bird in the breeding grounds who has a different over wintering site?
Whose site do they go to now they are a pair?
In many species the pair bond breaks up at the end of the breeding season, but some like swans mate for life.
In the case of the Bewick's Swan the male decides where to fly to for the winter and the female follows him.
However, the female decides when it is time to travel back to the tundra for another year's breeding.
The reverse scenario is when birds with different breeding sites overwinter in the same area.
If pairing commences on the over wintering ground, whose breeding ground to they return to.
The answer may be different for different species.
For example, the male Mallard duck follows the female.
Timing of migration is a mix of internal stimulus.
Feeding binges are followed by the aggregate tendency into flocks.
Once the pre-migration flock is gathered, the feeding continues while the birds wait for suitable weather conditions.
Thus while the birds' internal clock probably releases the hormonal triggers at a fairly accurate date each year, the availability of food and the presiding weather conditions can decide when the migration start each year.
As I mentioned last week, length of day triggers migration, but food is the driving force behind it.
Okay, here is an interesting point that you may not realize or understand.
In fall, migratory populations that nest farthest south migrate first to the winter range because they finish nesting first.
For example, the breeding range of the Black-and-white Warbler covers much of the eastern United States and southern Canada northwest through the prairies.
It spends the winter in southern Florida, the West Indies, southern and eastern Mexico, Central America, and northwestern South America.
In the southern part of its breeding range, it nests in April, but those summering in New Brunswick do not reach their nesting grounds before the middle of May.
That means 50 days are required to cross the breeding range, and if 60 days are allowed for reproductive activities and molting, they would not be ready to start southward before the middle of July.
Then with an assumed return 50-day trip South, the earliest migrants from the northern areas would not reach the Gulf Coast until September.
Since adults and young have been observed on the northern coast of South America by August 21, it is very likely that they must have come from the southern part of the nesting area.
Some of you live in the Southern 1/2 of the United States and have mentioned the lack of hummingbirds.
As I mentioned earlier in this letter.
Though my regular hummers departed on their normal times, a stranger came to visit on October 1st and 2nd.
Now, these hummers have to go somewhere.
Your local birds may be gone, but expect our northern hummers within the next few weeks as the bottle neck their way to Texas and the Gulf Coast.
Expect this with several species of migrating birds.
There are many examples of northern birds showing up along the Gulf Coast states as southern breeding birds arrive at their winter homes in South America.
What does that mean you?
It means there is a lot of migration going on and you have a good month or two of watching birds.
Characteristically, one will observe a few early individuals come into an area followed by a much larger volume of migrants.
This peak will then gradually taper off to a few lingering stragglers.
How do scientists know where birds go in winter?
Traditionally, the only way to find out where an individual bird went was to capture and mark it, then wait for someone to find it again by chance.
Though the odds are small, sometimes birds are recovered far from where they were originally captured.
For example, over a period of 40 years, biologists at the Long Point Bird Observatory in Ontario, Canada, placed aluminum bands on the legs of 39,044 Swainson’s Thrushes.
Only two of these thrushes were recovered on their wintering grounds, by members of the Asheninka native community in northern Peru!
In recent years, satellite transmitters have given scientists an unprecedented opportunity to track birds around the globe.
The transmitters emit signals that are picked up by space satellites and reported to a computer back on earth.
Using this technique, scientists have documented a Peregrine Falcon migrating from Alberta, Canada, to Mazatlán, Mexico.
They have tracked Swallow-tailed Kites from Florida and Georgia to previously unknown wintering grounds in Brazil, some 5,000 miles away.
A Swainson’s Hawk traveled from California to the pampas of Argentina, where it revealed a gathering of thousands of other Swainson’s Hawks, including hawks that had been banded in California, Colorado, and Saskatchewan, Canada.
In most cases, ornithologists know little about exactly where birds from particular regions spend the winter.
Often the best information they have is based on where the species is found at different times of the year.
North American birds vary widely in their travels.
Some birds simply cross a state line or fly from the mountains to the valley.
Some birds travel from the Arctic, they may winter in your backyard or half a world away.
Still other birds pack the speedos and suntan lotion and head for the tropics.
Your homework assignment is to find out where your birds go for the winter and where your winter migrants come from.
No matter where you live, you can build a list of migrants.
Where do they come from and where do they go.
No grade, just satisfaction on your part.
Now Here Are Some Migratory Marvels:
Body lengths traveled by a Rufous Hummingbird between Alaska and its winter range in Mexico:
Miles to the gallon used by a Blackpoll Warbler on migration if it burned gasoline instead of body fat:
Miles traveled by an Arctic Tern in its annual round trip between Arctic breeding grounds and Antarctic seas:
Estimated number of birds detected by radar passing over Cape Cod, Massachusetts, on a single autumn night:
Sources: Smithsonian Migratory Bird Center.
I thought I could get migration done in two letters, but Part 3 will be next week.
I hope you don't mind.
There have been some interesting studies on migration and I want to share a few of them with you and some of my thoughts as well (this is where I get myself in trouble sometimes).
How do they do it?
When do they sleep and much more.
Creation is a grand thing and displayed on a grand stage for all of us to enjoy.
Our Living Planet.
Be sure to tune in next week.
It's time to fly.
Before I go, here is your thought for the week.
Attitude determines altitude.
A very simple thought with profound results.
In nature, attitude is survival.
Wake up with a poor attitude or or an I don't feel like that today, you could be a goner.
Thankfully, birds have the right attitude so they can reach the needed alttitude.
Do you have the right attitude?
Are you reaching your maximum altitude?
It not to late.
Sure, for some of us it is to late physically.
But what about emotionally and mentally?
Have you stretched your wings?
Are you going to scratch with the turkeys or soar with the eagle?
Me, I want to soar with the eagles.
You can too, by starting today with the right attitude.
Nothing gets you in the right mood faster than a big smile.
Wear that smile and share that smile.
The first step is up to you <
Until next time my friend
"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,
PS. If you enjoy these letters, please forward them to friends, family and co-workers. Better yet, have them sign up so they can recieve their own letters.
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