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Fall Migration Part III
October 24, 2011
Thank you Lord, my nephew is home safe and sound from Afghanistan.
It isn't a popular place to be, and many have perished, but we haven't been attacked since we started bringing it to them.
Allow me to take a moment to Thank All of our Military Men an Women past and present.
Freedom isn't Free, it comes at a great cost.
Prayers for all that have lost loved ones.
Thank You for this moment.
The Dark-eyed juncos have made it to my part of SW. Michigan this past weekend.
The pictures of the butterflies were taken this past Monday.
A sunny and 55 degree day gave me some late season guests.
Even a Monarch or two stopped by (really late bloomers).
Top picture is a Buckeye, followed by a Red Admiral and then the Monarch.
The Red Admiral and Buckeye will simply hibernate when it becomes to cold to function and pop out in the spring.
The Monarch is unable to move when the temperatures drop below 40 degrees F. and will eventually perish if they can't make their way to wintering grounds.
Thankfully I still have some blooms for them to nectar on and yes, we are enjoying them too.
Yard and garden work is continuing at a snails pace, when the weather allows me to get outside that is.
Here are a couple of tips for you, if you don't already employ them.
As you cut down and clean up beds, you may consider leaving in your gardens, what was healthy plant material.
Stuff like hosta foliage, iris
Toss your vegetable based garbage out in the gardens and beds.
Allow it to decompose and enrich the earth on location.
All fungus and virus infected plants, you want to discard in the trash (no compost).
Okay, it may look a little messy, but who cares?
Work it into the soil now.
Grass clippings are mostly nitrogen and decays quickly.
Tree leaves (trees in general) are mostly carbon and are slower to break down, but everything thing needs carbon.
Mulch your leaves and spread them on top or better yet, till or dig them in.
By turning over your soil in the fall, you accomplish a couple of things.
First, the plant material gets a jump on decomposition and is pretty much broken down when it is time to plant next spring,
Second, the dirt clogs will dissolve away over winter, leaving you a nice oxygen rich unpacked soil ready to plant in net spring (without having to dig again).
Excess mulched leaves can be used as mulch or a winter cover.
Be sure to mulch leaves, especially maples as they will form a mat that deters water, sun and oxygen from reaching the surface.
All woody perennials like Agastache (hyssop), Perovskia (Russian sage), Lavandula (lavender), etc. should wait till spring to cut back.
This hold true for Buddleia (butterfly bush).
Especially if you live in the more temperate zones (3-6).
Over the past few weeks, I have been writing on birds and bird migration.
You discovered that birds are equipped with very special and unique lungs (unlike any other creature) and special muscles to draw on the oxygen rich blood.
You understand how hormones and length of day are the primary indicators for migration.
Well, I've dug into the archives once again and decided to finish off the series today and next week.
With all of the special equipment "Nature" has provided our avian friends, there is still one more unique item.
Healthy feathers serve many purposes for birds, it could be for mating purposes or for migration.
Over the next couple of weeks I hope to give you a better understanding and the important rolls that feathers have in a bird's life.
Whether this is a refresher course, or new to you.
Sit back and enjoy.
I realize these newsletters are much too lengthy, but I figure you deserve a bit more than just a few basics on any topic.
To do it right, you deserve to have more information given to you than a simple paragraph or two.
And I will try to deliver.
Thank you for your patience, take your time, and once again, enjoy.
For the past few weeks, I've talked on bird migration.
From the special and unique muscles and lungs that birds have.
To staging and migration itself.
Flight and migration also requires another piece of unique equipment, only possessed by birds.
The mighty feather.
While adult and breeding plumage is crucial for the reproduction of a species.
Flight and Migration require strong and healthy feathers.
The replacement of all or part of the feathers is called a molt or Moult.
For every one's sake, I will use 'molt', in this letter.
A feather is a "dead" structure, somewhat like your hair or nails, except your hair and nails continue to grow.
We can cut off split ends and trim up and manicure cracked nails.
Since feathers cannot heal themselves when damaged or keep growing like a finger nail or hair, they have to be completely replaced.
Damaged and worn out feathers are replaced during a molt.
When a feather that has been lost, it completely is replaced immediately.
The hardness or strength of a feather is caused by the formation of the protein keratin.
Molts produce feathers that match the age and sex of the bird, and sometimes the season.
Molting, like migration occurs mostly in response to a mixture of hormonal changes brought about by seasonal changes (typically length of day).
The entire process is complex and many questions remain regarding how the process takes place.
Often Einstein like equations are used to show body weight, energy used and so on.
No need to bore you with that stuff, (besides I don't understand all of it myself).
A basic understanding of molting patterns can however, be a useful aid in identifying many species and in determining their age.
In temperate zones, cue for molt initiation is day length, which has an effect on the hormone levels that ultimately control molt progression.
Molting is very costly, as it consumes energy and can cost a bird in its ability to fly.
The bird replaces 25 – 40 percent of its dry mass, drawing on protein and energy reserves to make and grow new feathers and to offset the effects of reduced insulation and flight ability.
Because it is so costly, molt is often interrupted in order to begin breeding activities or for migration.
Common white terns molt almost continuously to replace their easily worn, unpigmented feathers, but interrupt molt upon laying an egg.
Some migratory birds like the Peregrine Falcon and American Golden Plover will interrupt molt to migrate and resume it at the end of migration.
Something we don't think about when we think about birds molting is this.
Many birds go through a quick series of plumages in their first months of life, and then cycle between a basic, or winter, plumage worn for most of the year and an alternate, or breeding, plumage worn only during spring and summer.
This may bore you to tears, but here is a plumage sequence and molt.
Many bird watchers are used to thinking of the often brighter summer plumage as a bird's main look, so this system may confuse you at first.
Birds that have a breeding and non breeding plumage are usually in the non breeding plumage for a longer period of time from late summer or early fall to early spring.
Often following a full molt.
In most north-temperate passerines, the first and adult prebasic molts usually take place from July–September, just after the breeding season.
Prebasic molt usually takes place on the breeding grounds, but may take place during fall migration or on the winter grounds.
In adults, the prebasic molt is usually complete and results in the adult basic plumage.
In first or hatch-year birds, it is referred to as the first prebasic molt and results in the first prebasic plumage.
The first prebasic molt is not complete, since the feathers of the primaries and tail are often not replaced.
The second prebasic molt is complete, and results in the second basic plumage, which is generally the adult definitive plumage (adult basic plumage).
Many birds don't reach their true adult colors until the second basic molt (much longer for some birds like Bald Eagles).
This may or may not deter mating, depending on species, locations and other factors.
The basic plumage is generally worn during fall, winter, and early spring.
In first or hatch-year birds, it is called the first basic plumage and is not the definitive (final adult) plumage, since the feathers of the wings and tail are generally not replaced in the first prebasic molt.
These feathers retain qualities of the juvenile plumage, making birds in their first basic plumage generally distinguishable from those in their adult basic plumage.
The adult basic plumage is the definitive plumage to which adults return after every breeding season.
Juvenile passerines generally achieve the adult basic plumage by their second basic plumage.
Some non passerines (gulls, eagles) and some passerines (orioles, manakins and even goldfinches) take more than 2 years to reach the definitive plumage.
In some birds, the prebasic molt is the only molt that occurs annually; thus, breeding occurs in the basic plumage for these species (American Robin and the woodpeckers).
In most passerines, the prealternate molt causes the replacement of the basic plumage with the alternate plumage during winter or spring.
In hatch-year birds, it is called the first prealternate molt and results in the first alternate plumage.
In adults, it is referred to as the adult prealternate molt and results in the adult prealternate plumage.
Prealternate molts are generally partial, though the extent of the prealternate molt varies substantially among species and between male and female.
Alternate plumage In adults is referred to as the adult alternate plumage, whereas in hatch-year birds, it is the first alternate plumage.
In many passerines, the adult alternate plumages of males differ from their adult basic plumages, whereas in females, both plumages are similar.
Birds in their first alternate plumage are generally duller than those in the adult alternate plumage.
There are two kinds of molts with different degrees of feather replacement.
In a complete molt all feathers are replaced.
In a partial molt only some feathers are replaced.
It takes a lot of energy to build new feathers.
Molting is, therefore, often timed to coincide with periods of less strenuous demands, such as after nesting or before migration.
Still, some birds molt during migration.
Some birds molt after migration.
Some birds start and stop during migration.
There is no definite time for molting.
Molting, like migration takes place all through the calendar year.
Indeed, it may take a Bald Eagle a few years to finish a single molt cycle, only to start all over again .
It takes a good 5 years and a series of molts to reach adult Bald Eagle plumage.
How often do birds molt?
This varies by species, but almost all birds fall into one of the following three categories.
Many species have one complete molt per year.
Chickadees, Flycatchers, Hawks, Hummingbirds, Jays, Swallows, Thrushes, Vireos, Woodpeckers, Owls and hundreds of other species.
Some species have a complete molt after nesting, molting into their basic plumage.
These species then have a prenuptial molt of body feathers that results in their bright breeding plumage.
Species with this molt pattern include:
Buntings, Tanagers, Warblers and American Goldfinches.
While females of these species usually look very similar on a year-round basis, they do go through a partial prenuptial molt and can be described as being in alternate plumage for part of the year.
The male American goldfinch undergoes a complete molt in the late summer/fall that results in a drab olive green to dull brownish/yellow bird with typical goldfinch wings.
In spring the male American goldfinch undergoes a partial molt, including the body feathers.
The new body feathers are a brilliant rich canary yellow color.
Some species undergo two complete molts each year.
Bobolinks for example, go through two complete molts.
After breeding all the feathers are molted and the male looks very much like the female and this often confuses bird watchers.
For spring or mating, he goes through another complete molt to get his beautiful black and white 'Bobolink' colors once again.
Some species acquire their adult plumage in a single year.
Others require up to five years (eagles) to reach full adult plumage.
Gulls are often broken into categories such as a "three-year gull" or "four year gull," based on how long it takes the bird to reach full adult plumage.
Some birds of a same species will start molting earlier and others later.
Still other birds like waterfowl have some different molting schedules all together.
Molting patterns vary by:
Individual birds of the same species.
By individual feathers.
Next week I'll go over a few basics and add some more to it.
I'll may write a short bit on certain species like hummingbirds, swallows, loons and a few other birds that our 'Creator' has given special adaptations and schedules to molting.
What to offer birds at your feeders and why.
Interesting or not, you now have a basic understanding of molting.
Well, it is time to fly for now.
Before I go, here is your positive thought for the week.
You can preach a better sermon with your life than with your lips.
Oliver Goldsmith (1728-1774) Irish Writer
From the Good Book.......
Who is wise and understanding among you?
Let him show it by his good life,
By deeds done in the humility that comes from wisdom.
James 3:13 (NIV)
"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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