Common Grackles Dining on Acorns

If you happen to be outside when a flock of grackles arrives, you may want to take shelter!  It may rain acorns!

When mature acorns are abundant in early autumn, flocks of grackles noisely move from tree to tree feasting on the juicy nut meats. The first time a roaming flock landed in the oaks over my house, it sounded like hail was pelting the roof.  I looked out on the deck to see leaves, twigs and pieces of acorns falling like rain from Southern Red Oaks overhanging the house and deck.

Common Grackles noisily feasting in a Red Oak.

While we usually think of grackles as feeding in fields and on the ground, they also dine in trees.  While most of the grackles were in the limbs, some were also foraging on the ground underneath, picking up fallen nut pieces. It was the nut pieces with their serrated edges that intriqued me.  I wondered how they were cracking them open. 

Some birds swallow acorns whole, like wild turkey and some species of pigeons.  They can rely on their strong gullet muscle to crush them for digestion.  Blue Jays pound the acorns with their beak to break them and eat the soft meat inside.  Grackles, on the other hand, have special mouth parts and a strong beak that equips them for breaking acorns.  Their hard palate has a projection referred to as a "keel" that extends downward.  Bird beaks are hinged but they can also flex and move side ways slightly.  Grackles push the acorn against the keel, scoring the shell until it cracks open and the soft interior is exposed.  The edges of the broken acorn look a bit like they've been primatively sawed.  The grackle eats part of the nut and the rest drops to the ground for flock mates to eat.

The acorns of the Southern Red Oak are bright orange on the inside.

The next time a flock of grackles lands in a tree in your yard, step outside to see what's going on.  It's magical.  Besides the sound of their calls and the energy of activity, they are also acrobats!  Some will be hanging upside down to reach acorns!

Resources:
A. J. Marshall, Biology and Comparative Physiology of Birds, Vol 1:  The Common Grackle (Quiscalus) has a hard keel projecting downward from the horny palate and regularly uses this in opening acorns or cracking corn.

Birds of North America/Common Grackle:  Bill has hard, internal keel projecting downward from horny palate, which is sharper and more abrupt anteriorly.  This keel extends below level of tomia [toothed projections along edge of beak] and is used as sawing adaptation to open acorns, which are often completely scored around shorter diameter and then cracked by adduction.

You may also enjoy these bird behavior posts:
Tail Signals from a Spruce Grouse
Delightful Limpkin

Bird Parents and a Killdeer Ball of Fluff

I was headed out of my office tonight to go home.  As I was locking the door, a Northern Mockingbird flew toward me, squawked and landed on the step railing near me.  I said, "What?  Do you have a youngster out here somewhere?" (Yes, I do talk to birds.)

I looked around without moving and discovered a pristine juvenile sitting on the sidewalk, two feet away.  

Killdeer chick above.

The white edging of the juvenile's plumage was brilliant against pale gray feathers and when she looked up at me, her yellow gape was SO yellow.  I wondered if she had just fledged.  I stood without moving and coaxed, "You need to fly."   A few beats later, she flew to the holly with parent close behind.

Bird parents.  They are loyal, hard working, vigilant.

And that brings me to killdeer. Along with mockingbirds, this is a bird I have known and loved since childhood.  I first became acquainted with them in farm pastures, their loud cries on the wing unmistakable.  My latest encounter was last week in the grocery parking lot.  But it was not until my June visit to Brevard County, FL, on my way to the Pelican Island Overlook at Sebastian Inlet, that I actually witnessed the famous broken wing display.  Immediately, I was on the alert for young.  

And what we found (I was with Marge Bell and Jim Angy of Brevard County) was this little fluff ball, busily foraging on long legs.  If you enlarge the image below, you can see the webs on the chick's feet.  Though killdeer, a plover species, are found in many dry open places frequented by people, such as ball parks, gravel roads, abandoned fields and parking lots, they are also wetland birds.  And both the adults and juveniles are proficient swimmers.

But our visit with the juvenile was cut short by an unhappy parent who let out an ear-piercing alarm call.

She got our attention and the attention of the juvenile who immediately adopted a crouched, motionless posture and blended with the dead debris on the ground.

Nature at her best.

To see my previous posts on the Space Coast, Brevard County, FL click here

For more Brevard County Links visit:
Space Coast Beach Buzz
Jim Angy Photography
Space Coast Wildflowers

Linked to Bird Photography Weekly #99 at Birdfreak.com to promote the conservation of our world's birds.

And don't miss your chance to win a free copy of the 8th Edition of Simpson and Day's Field Guide to the Birds of Australia. Visit my book review and leave your comment before midnight (EDT) July 31st.  The Winner will be announced August 1st and receive their free copy directly from Penguin Australia.  Good luck!

Berry Dining--Sapsucker Style

It was his soft mewy call that caught my attention, that distinctive low whine that sounds a bit like a cat's mew--the wintering call of a Yellow-bellied sapsucker.

Besides dining on sap and insects, these woodpeckers also happen to like holly berries. And since there is a holly within view of my window, its handy to look out from time to time to see whose come to dine.

Some of the sapsuckers that visit the yard have come down from the higher elevations in the nearby Smoky Mountains. Others have traveled to winter here from more northern breeding grounds. November to late March is the time of year we get to enjoy their visits in the lower elevations of the Tennessee Valley.

Watching this male forage on berries not only provided enjoyment, it raised many questions as well. Like, do birds actually loose their balance and misjudge their footing? Maybe that seems obvious, but it's not something we often see or consider. It certainly seemed to be the case with this sapsucker. In the image below you'll see one foot dangling while he appears to have caught himself with his chin. (Click the image to enlarge.)

But he recovered quickly and moved right on to pluck another berry.

And then eyed another one.

And as he plucks this berry, take a look at the image below. It appears he's holding one, maybe two, berries in his gullet while adding another one. Just how does that work? How long will he hold them there? And how many can he collect there at one time?

I don't know the answers, so if anyone one else happens to know or knows an expert who knows, or can recommend a resource, that would be great.

While browsing the subject of sapsucker dining, I did learn another new tidbit about their habits. Sapsuckers lap the sap from their excavated tree wells in much the same way as hummingbirds lap nectar from flowers or feeders. But unlike hummers, the Yellow-bellied sapsucker has hairs on his tongue that help facilitate the lapping of sap. To see an image of a sapsucker's tongue, click this link to Hilton Pond Center.

Above, is another image of the same sapsucker perched on the tree stump in front of the holly. Though Yellow-bellied sapsuckers can sometimes look drab because of their blended plumage, this backlit male was striking with his crimson throat and cap, the sharp contrast between black and white areas of plumage, and that golden glow on his belly

Besides being my first bird photographs for 2010, he earned the honor of becoming my first bird sketch of the new year, too. And I can say I am happy to hear their soft mewy calls mixed in with the other woodpecker calls in the area.

Linked to Bird Photography Weekly #72 at Birdfreak.com to promote the conservation of our world's birds.

Who's Boss?

There's a favorite perch near my front door. It happens to be the stump of an old apple tree, long since down, positioned, very handily, in front of a holly bush. And right in front of the holly stands the bird bath, a favorite place for birds to visit in the winter when they're looking for an unfrozen source of water. Most every bird eyeing the feeders or stopping by for a drink, will at some point take their turn on the old apple stump. Mockingbirds, jays, towhees, sparrows, titmice, chickadees and Downies, and most recently, a male Red-bellied Woodpecker. It's the taking turns part that has caught my attention recently, on more than one occasion.

Watching the birds interact at the feeders can sometimes be surprising. Mostly, they seem to come in waves, each bird, taking their turn, peacefully waiting for whoever is feeding to grab their seed and go. But I see other types of behavior, as well, like two titmice, a goldfinch, and a Downy, all feeding at the same time. Or when the seemingly peaceful White-breasted Nuthatch starts wing-flexing and warning everyone else away. And then there's the Bluejay who sometimes flies in like a thug and dethrones the Mockingbird from the holly perch.

I've seen many birds shy away from the Mockingbird, but this is clearly not always the case. On this occasion, a Red-bellied male landed on the perch. I slowly nudged the door open with my foot, hoping to get an image or two without disturbing him. With my eye to the camera, and my focus on the woodpecker, I heard a commotion but didn't pause to look until I had captured the two images below.

In the first, the woodpecker has flared his wings and tail and faces the intruder, a Mockingbird, with his beak high. If you enlarge the image and check the very top, you'll see a bird foot on the perch.

The Mockingbird tried one more time to claim his spot, but not only did the woodpecker not budge, he moved toward him. The Mockingbird settled for a nearby limb and the Red-belly reigned...this time.

Doesn't he look regal with his sunlit red head and fanned tail?

So regal, that I thought he deserved a place in my sketchbook.

And there was space for the mocker, too.

What can I say? They're all boss!

Linked to Bird Photography Weekly #70 at Birdfreak.com to promote the conservation of our world's birds.

Tufted Titmouse--Singing in the Rain

If someone were to ask me, why do you love birds so much? I might have to answer, have you ever met a Tufted Titmouse?

Today is a cold, rainy November day, the kind of day we expect to have this time of year in east Tennessee. But after yesterday's brilliant sunshine, who can complain. And this one was brightened for me by the colorful Tufted Titmouse family, one of whom landed on the empty feeding table outside my door and scolded loudly. (click on images to enlarge)

After I put the suet out, I noticed him happily singing on the holly. I stepped out with my camera hoping he would continue and let me get a few images. As you can see, he didn't seem to mind. Even when a couple of chickadees flew in, attempting to dethrone him, he just turned and sang some more.

A colorful part of every season, these little birds are so much fun to have around. If you haven't met one, introduce yourself!

Linked to Bird Photography Weekly #65 at Birdfreak.com to promote the conservation of our world's birds.

Posture is Everything!

I just paid a visit to Operation Migration's website to see how training went this morning. What I discovered was a wonderful video clip, something you will want to see, a pair of wild Whooping cranes threat posturing.
When you view the video below, you will see two adult Whooping cranes walking with their heads down showing their bald, bright red skin patch. Cranes can engorge this skin patch with blood, making it larger and redder. When they hold their heads down, the skin patch is prominent and represents a warning to intruders that an attack could follow.

Chris Gullikson, one of Operation Migration's costume-clad pilots and the videographer, is also posturing by holding the red head of his Whooping crane hand puppet high in the same position. Size matters in the Whooping crane world and Chris, whose human shape is covered with a white costume, represents a larger threat in crane posture language.

As you view the video below, don't miss the stomping that occurs early while the bird to the right is still in the shadows. He repeats it later. You can hear it as well. Stomping is an additional threat behavior. Also, remember that Whooping cranes are five feet tall with a wing-span of seven feet!

The reason for the encounter? Chris is at Necedah National Wildlife Refuge and is discouraging the pair from interfering with the ultralight migration training by trying to lure the juveniles away. You can see Chris' shadow as you view the video. At the end of the clip, the pair flies over to another wild crane who has trespassed into their territory. After they chase him off, they sound the unison call, trumpeting their successful defense of territory. The unison call also serves to strengthen the pair bond.

Great clip, Chris and Operation Migration! Threat posturing, a rare glimpse into the lifestyle and personality of Whooping cranes.

Check out migration training as it progresses at Operation Migration's field journal or by watching the cranecam as training is underway. And don't forget to Give A Whoop!

Linked to Bird Photography Weekly #49 at Birdfreak.com to promote the conservation of our world's birds.

Barn Swallow Juveniles in Action

When its summer time and you're freezing inside a building, the best thing I know to do is step outside for a while.

And so I did. And while doing so I discovered these adorable swallow juveniles resting on a ledge. In the air overhead were dozens more juveniles and adults flying and calling. What a delight to listen and watch their acrobatic aerial displays over the man-made pond and fountain. Not only were the swallows catching insects attracted to the water, but they also flew along the surface to drink. Amazing to watch. And the thought of these juveniles learning and practicing feeding and drinking in flight was pure delight. I watched them take flight more than once, returning a few minutes later to rest and preen. (Or maybe it was their young cousins' turn to rest.)
Swallows were among the earliest birds to capture my interest as a child. Having grown up around barns and having a barn of my own in later years, I've always considered them endearing companions and neighbors.

A nesting pair of barn swallows frequently perched on my barn gate in the early mornings and chattered while I fed horses. Even while feeding their young, they went about their business accepting my presence as readily as I accepted theirs.
Linked to Bird Photography Weekly #45 at Birdfreak.com to promote the conservation of our world's birds.

Greater Sandhill Cranes—Are We Dancing?

I’m leaving the backyard for a bit to muse about sandhill cranes and their enchanting behavior, a species that captured my heart about ten years ago. But I'm not alone. People have watched them for centuries and used their behavior to symbolize good health, long life, peace and happiness.
And this reverence is well-earned. Like many animal and bird species, cranes mate for life, are territorial and protective of their families, and show emotion, including grief when a mate is lost. Sandhill cranes migrate in large flocks of family groups. You hear them even before you see them, that wonderful melodious call that fills the air and causes you to look up with wonder. And then you hear the tiny "peeps". The juveniles, though nearly the size of their parents, still have their chick voices until their vocal chords mature sometime near the end of their first year.
Animal behavior has always been one of my loves, second only to people behavior. So it was with great pleasure that I attended an eight-hour crane behavior workshop at Bosque del Apache National Wildlife Refuge in San Antonio, New Mexico several years ago.Sandhill cranes are peace-loving birds but it is their wonderful array of postural communication that allows them to co-exist in harmony while in wintering flocks of thousands. Though they do not require a large territory while staging, they still have territorial boundaries within the feeding area and they protect their feeding space with determination.
The crane above is not dancing. Though elegant and full of grace, he is displaying aggression. Cranes use a variety of postures and vocalizations to let intruders know they aren’t welcome.

Among the postures are the head down position below, showing the bald red patch which can be engorged with blood to intensify color and display aggression or excitement.Above you see a crane family with the male in front with head down, the juvenile in the middle and the female in the back. You will see some mud stains on the adults from painting themselves, a ritual that is of uncertain purpose but believed to be a part of courtship and an assist to camouflage while nesting.
Notice that the juvenile below still has rust feathers on his head and his wings and he has not yet developed the adult white facial marking. The rust feathers on the juvenile are more uniform in appearance than the painted mud stains on adult breeding birds.

The feather ruffling you see below serves as a mild threat called a ruffle threat--a general expression, "you better not mess with me".

And the crane below, after issuing some warning calls, is getting into some serious displays of attitude and intent to defend his feeding territory.
These behaviors are usually sufficient to cause the intruder to back off. But when retreat does not occur the dispute intensifies and dust flies.

Cranes avoid physical disputes whenever possible using calls and posturing. When disagreements escalate to the point of contact, they are settled rapidly and peace is restored. Maybe the human species could learn a few pointers from cranes.