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Those Dreaded Cowbirds
June 08, 2009
Welcome and blessings.
Thank you everyone that commented on last week's positive quote and thought.
We are powerful and creative people.
The temperatures are still below normal around here.
That isn't so bad as it still feels very much like May.
Most of my May bloomers are still showing off (Lupines in my garden).
Because of the cooler days, windows are still wide open and the electric bill gets a rest.
Now that isn't so bad is it?
This was one of those hectic week-ends.
Yolanda went in for surgery on Friday to have a Baclofin pump inserted and a line running from her groin area to her spine.
We brought her home late on Saturday and spent a good portion of the middle of the night (Sunday morning) cleaning up messes etc.
Baclofin helps with the spasicity of her leg muscles and hopefully help us with transfers and theropy.
Like the poor girl hasn't been through enough through the years.
Prayers go out to all readers. I know of some that are in real need.
SNOW in June?
Come on now............
upon further observations, I see it is the fuzzy seeds from the many Cotton wood trees in the area.
Though the stuff can mess with pool filters, several birds enjoy the fluffy down as they are busy collecting it for nests.
June is also strawberry season and that too is running late.
I realize that many of you are veterans of the strawberry patch, but in case there is one or two of you that may not know this.
Strawberries do not ripen any more after they are picked.
You must pick them red and ripe if you want ripe berries.
Fresh grown strawberries are the best.
Keep bird netting over your crop to keep the robins and other fruit pickers at bay.
It can be frustrating, having a small patch and finding your fruits half eaten.
Birds and more birds fill the yards as they are busy feeding fledgelings insects and fruits.
Still other birds are building their first nest while others are working on batch number 2.
The house wrens are happy with their home.
I have another nest box tucked away in a thick tall shrub.
Now, the chickadees knew it was there all along, but the late arriving wrens by-passed as the other boxes are in the open more.
Well, we have Black-capped chickadees nesting now as well (my favorite little bird).
A bit late for them, but I'll take it.
Cedar Waxwings are visiting the tree tops insect hunting.
Typically, we don't have Waxwings this time of year here in my little corner.
Keep you hummingbird feeders cleaned and filled (Aspects jewel box window feeder).
Even in the cooler weather many of us are having, the sun still beats hot on glass and plastic hummer feeders.
This time of year, cleaning every 2 to 3 days is a good habit to practice.
Sometimes more often.
Hummingbird feeders are becoming more popular as many want to attract these flying jewels.
To often newbies and well intended people, put up a feeder and forget it.
Then, they wonder why they don't have hummers.
Important information, read feeding hummingbirds.
Dead insects poison the sugar water.
Hummers may feed and get sick or die.
Feeders typically are a supplement for flowers and nectar, but as more habitat is destroyed, the more the diminutive bird needs human help.
Develop good practices and habits and you will be rewarded.
Planting attractive flowers will bring them in as well.
Have you noticed one or several dead sparrows or other small birds in your yard or gardens?
A couple of weeks ago, I witnessed a brutal attack by a Common grackle on a house sparrow.
A few other times I have heard the ruckus, but have never witnessed the after math like I have this year.
No less than 8 dead sparrows in the past two weeks and many of them have their heads pecked open and brains eaten.
I know grackles are a member of the crow family, and I know they eat babies etc.
I even know they killed sparrows and other smaller birds from time to time, but I did not know they had a thing for sparrow or bird brains.
If you come across a sparrow or other small bird and the head is mutilated, you can figure a grackle has been there first.
Grackle populations are up around here, I'm sure that plays a part in what is going on.
Well, that brings me to this week's main topic.
Yes, another bird that is near the bottom of most bird lovers list.
In this case, Brown-headed cowbirds.
The Brown-headed Cowbird (Molothrus ater):
North America's most notorious brood parasite.
The Brown-headed Cowbird is one of two species of cowbirds found in North America. The other is the Bronze-headed cowbird, found in the southwest United States.
Both species are brood parasites that lay their eggs in the nests other birds.
Formerly occurring in the central grasslands of North America, wholesale clearing of forested land has allowed the Brown-headed cowbird to extend its range across most of North America, and to increase its population dramatically.
Yes, they thrive in open lands and woods edge where many of our song birds nest.
Incapable of nesting, incubating, or raising babies, the Brown-headed Cowbird found one solution.
Instead of building their own nests, incubating their own eggs and raising their own nestlings, Brown-headed Cowbirds have a different breeding strategy.
It lays its eggs in the nests of other birds.
More than 220 host species have been parasitized by cowbirds.
Cowbird chicks have been successfully reared by over 150 host species, with songbirds comprising the majority of hosts.
Notice, that in most cases, the cowbird eggs is larger and very similar in coloration. In most cases, this give the cowbird chick another advantage.
Brown-headed Cowbirds occupy most of North America south of the Arctic, but this large range has occurred only recently and is the result of human-induced factors.
Prior to the arrival of Europeans in North America, cowbirds were nomadic, following the large herds of bison that roamed across the Great Plains.
It is believed that this localization kept the population in check.
According to researchers, Cowbirds are prolific egg layers, laying 40 to as many as 80 eggs in a season.
Now that is reproduction.
Female cowbirds search for nests by quietly observing other birds, and also by making hard landings on leafy branches while flapping their wings as if intentionally trying to flush birds off their nests.
When a cowbird lays an egg, it usually tosses a host egg out of the nest.
Many hosts donít seem to notice the replacement, and when they do, if they try to toss out the cowbirdís huge egg with their relatively tiny bill, they sometimes scratch or pierce their own eggs.
When a host bird does remove a cowbird egg, the cowbird may return to destroy the remaining eggs.
Some host birds may successfully raise both a cowbird and one or two of their own, but in some species, the cowbird is almost always the only survivor.
Neotropical migrants with limited ranges, such as Kirtlandís warbler, are exceptionally vulnerable to cowbird parasitism.
Here in Michigan, The Department of Natural Resources has taken an active roll and plucks the cowbird eggs from known nests.
By doing so and better land management, Kirtland's warbler population is growing and expanding every year.
The worst case scenario may be experienced by the Black-capped Vireo, which breeds in scrubland in a very restricted and shrinking range in Oklahoma and Texas.
With Black-capped vireos, research shows as many as 90% of their nests fall victom to cowbirds.
In the 1980's at one Oklahoma site untrapped for cowbirds, 14 of 15 observed nests were parasitized. That entire population is now believed extirpated.
But in areas where cowbird parasitism levels are reduced to 3 percent of observed nests, many female vireos successfully fledge two vireo broods in a season.
In the Wichita Mountains in Oklahoma, wildlife managers have been trapping more than 90 percent of local cowbirds every spring and summer since the 1980s.
Here, the Black-capped Vireo population, though precariously localized, now thrives, along with Painted Buntings, Summer Tanagers, Blue-gray Gnatcatchers, and other songbirds that produce many more young every year without nest parasitism.Here is the the Cowbird key to success.
While most song bird eggs hatch in 12 to 14 days, (the Black-capped Vireo has an unusually long incubation period of 14-17 days).
Cowbirds hatch in 10, 11 and maybe 12 days, so it always has at least one day head start, but is 4 or 5 days old by the time the first vireo hatches.
Each time a songbird returns to its nest, it feeds the baby with the widest gape, which normally is the hungriest baby.
If the cowbird is larger than the other nestlings, it gets the lionís share.
This leaves a virtual 0% chance for the host eggs to hatch and survive.
Again, many ornithologists believe that cowbird numbers were once limited by high winter mortality and scattered bison herds.
Once bison were killed off, they introduced cattle and started growing crops such as winter wheat, vastly increasing cowbird winter survival and giving their burgeoning numbers an ever-expanding range.
Today, agriculture, development, and forest fragmentation maintain cowbird numbers at high levels.
The most effective way to compensate is to manage cowbirds.
Can you help?
It is illegal to remove native cowbird eggs without official blessings.
I'm not going to say.
Populations of Brown-headed Cowbirds are increasing at an alarming rate in many regions, estimated to be between 50 and 80 million birds (depending on what report you read).
Because they are brood parasites, they are a particular threat to populations of many other species of birds, especially endangered species such as Kirtland's Warbler.
Arguably, reduction of Brown-headed Cowbird populations would be of benefit to many other songbird and gamebird species.
Well, its time to fly for now.
Before I go, here is your positive thought for the week.
(Can you see the Chickadee above the box? I know poor quality.)
A friend is one who sees through you and still enjoys the view.
Wilma Askinas (1926- ) American Author
This one can sting...........
It can also be a blessing.
Actually, I think it is a blessing.
I have friends that know me, yet still want to be around me.
Do they see a clouded view?
Do they see a ray of sunshine?
Do they see a jumbled up mess and hang out with me because I'm good time?
Maybe they see a beautiful garden in me and all I need is a few weeds pulled and pointed down the right path.
Maybe they see through me and see I'm a good person despite some short comings.
As the saying goes "Beauty Is In The Eye Of The Beholder."
What kind of friends do I want?
The one that sees me as good time charlie, or the one that sees a decent person.
Maybe, all I need is a little tweaking.
A little support.
Maybe I need a wake up call or reality check.
A friend sees through that.
True friends let you know.
You and I look at the same swamp.
I may see a breeding ground for mosquitoes, stagnant water that can smell, etc.
You see a swamp full of life.
A swamp is home to several birds and small mammals.
a swamp helps to filter pollutants from reaching lakes and our drinking water.
Swamps are full of life, you explain to me.
You tell me I only have to look.
To open my eyes.
You show me.
When I open my eyes, I can see through the swamp.
I see what it is really about.
I see the true beauty.
Friends can look through us, see our faults and scars and still see the real beauty within.
Isn't it a blessing?
Others that care enough and can still enjoy the view.
People that can stand being around us.
A good friend is a blessing.
One you can let know you love them is even more rare.
now, From a man's point...........................
It is difficult if not rare to admit you have a friend you can hug and tell him you love him.
I am blessed to have one such friend (Jim) and to have a rare relationship with another man that we can freely hug and use the "L" word.
Jim and I both know we would go to battle for each other.
We share secrets men don't talk about etc.
We expect the other to say your wrong when it's needed, to chastise and then to support.
We also know there will be a hug and an "I'm here for you brother."
Friends that see through, and still enjoy the view.
Often, he is more of a brother to me than my brothers are.
I would love to have more friends like him.
Do we get on each others nerves from time to time?
The closet of relationships have these issues.
A friend will see right through your short comings, your habits, abilities and inabilities.
A friend knows what you may not see.
A friend looks through you and still enjoys the view.
These are people you need to say thank you to.
Tell them how you feel and what they mean to you.
Maybe thank them for putting up with you :-)
For keeping you going.
Friends that make you smile.
Now share that smile with friends and strangers.
You just might start a new friendship and all because of a smile.
Something else to consider.
Sometimes that friend can see your dreams and help you reach them (if you allow them in).
I know this isn't a typical pump you up positive quote, but this is worth mentioning many times over.
Until next time
God's many blessings.
"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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