Saturday, November 10, 2007

Mr. Kestrel Gets Lunch and Battles Wits with Crows


American Kestrel, Falco sparverius
Considered a true Falcon; It's about the size of a Blue Jay. And, thank goodness, a plucky country individual who could not have cared less that I was watching.
12:04:40PM
Temperature- 43 F.
Overcast
Smoke from Autumn leaf burning
Wind-Irregular gusts
County Road M

12:05:01PM Hunting success depends to a great extent on surprise. Kestrel sits quietly on an electrical wire first scanning one area and then another. Suddenly he stoops into a ditch.


12 05 24 He reappears, no prey, and selects a new position on the wire.

12:06:11PM Another swoop, and he returns to a new wire position with something small in his talons perhaps an invertebrate and eats it before I get a look.

12 08 12 New perch on wire adjacent to field of corn stubble. He looks alert and tenses.

12:08:31PM He triangulates, then the tension is released. He scans.

12:10:33PM Suddenly his head whips around, he's off the wire, hovers in the air, and then dives.



12:11:34PM Another new perch, slightly more screened by trees. He lands with a vole in his talons.

12:11:45PM Kestrel scans the area at his level.

12:12:18PM Then begins to prepare prey.

12:13:01PM See the contraction of his muscles as he attempts to get the prey open. Also note spot on top of head.

12:13:17PM

12:15:01PM

12:15:55PM

12:16:40PM Wing flap. Gust of wind? Just loss of balance due to holding prey on wire?

12:17:18PM Head up from eating. Listening?

12:17:49PM He's very alert and turns to watch opposite direction. Note how he has "squatted" on the prey, obscuring it partially. A completely different stance than his previous perching with the vole. He's up and then heads down into the cornfield stubble. I can't spot him.

12:19:37PM Suddenly Kestrel smartly maneuvers back towards me through the more densely vegetated portion of the border of the cornfield and lands on the sign. I can't see if he still has the vole or not. He watches as three American Crows fly over the cornfield.
A threesome of crows is often the number in a group that harasses other creatures for food. At the Red-tail nest at St. John the Divine, three crows work together in attempts to molest the eyasses. It was three Crows who attempted to steal the freshly caught prey of a Red-tail I watched mantling her catch in a cornfield last Autumn. They circled her on the ground getting closer and closer until she took off for the woods carrying her dinner with the Crows pursuing her for all they were worth.
But in this case the Crows seem to have flown over Kestrel. Kestrel takes to the air, whips through the branches in the hedgerow as only a falcon can do, and out of sight. I then see him again apparently coming from the cornfield he'd disappeared into previously. This time I can see the prey in his small very sharp talons. He hot wings it across the road and into a tree that is still densely leafed. He intends to eat dinner in a more secluded spot.
Did he stash his vole in the cornfield and then retrieve it again? I lean towards that ploy. But perhaps he only pretended to hide it and then squatted on his prey behind the edge of the sign as the Crows flew over. Either way, he's a very clever Kestrel.
Donegal Browne


















Friday, November 09, 2007

The Downy Woodpecker Makes A Visit


Downy Woodpecker, Picoides pubescens, female calls.


Suddenly there she is on top of the wire circle. She looks down at the suet and begins to descend towards it using beak, toes, and tail.
First she tries to access the suet with both feet still on the wire and bracing her tail on that side as well----She leaned. Unsatisfactory. (She's got a very hummingbird-like expression on her face. I'm wondering if it's manifested by focus over a lengthy beak.)
She moves her left foot to the feeder and braces her tail straight down against the wire. This seems to work better and she begins eating, her head and chisel shaped beak rapidly jackhammering the suet. She has a very long tongue which is barbed and sticky. It's barbed and sticky in order to retrieve insects and larvae from crevices and from under bark. Woodpeckers have bones in their tongues and like hummingbirds they fork in the rear and curl up around the skull. Add the muscles that control the tongue and you have the hyoid apparatus.
She stares fixedly and then goes for the jackhammer movement once again.

There's an abrupt stop and she stares north and east. The directions from which most predators come from in this location . Look at those toes. Her feet are zygodactyl, two toes in front and two in back like those of parrots and cuckoos. In the photo above she's extended the rear toes laterally or in an ectropodactyll manner.


When I zoomed in on one of her feet, it was very odd because it looked like she was wearing little scaly work gloves. The photo is somewhat deceiving.


Here is a better angle and you can see the double toes in the back. I couldn't find out if it is the case in woodpeckers but parrots are hatched with three toes to the front and one to the back. The far third toes in front gradually migrates to the back during chickhood.


Her foot back in a clutch, she goes back to eating.


Downy tails and those of other woodpeckers are marvels. They are a built in brace. But a brace capable of fine motor movement due to large muscles that control the stiff feathers, in some cases independently. The two longest center feathers are pointed. They have longitudinal ridges with hooked barbs that curve in towards the vertical surface creating more tail strength. The center feathers have a nearly unique molt pattern in that they don't molt out until the new ones have fully grown in.
Woodpeckers have a very jerky movement when navigating a tree as they hop with both feet while their tail supports them during the hop. And I would assume also adds some propulsion in the direction of the hop to help counteract gravity. A finely tuned system or gravity would just dump them on the ground unless they took to their wings.

And a favorite wonder I'd never noticed before, a pair of false eyes on the back of her head, formed by tiny dots of white feathers.
As Woodpeckers are all specialized in their specie's choice of habitat, they are more sensitive than some other species when it comes to possible extinction due to habitat loss. And even if their habitat remains but is fragmented to many edges, as cavity nesters, they are vulnerable to cavity predation by aliens such as the European Starling which can devastate their reproduction success.
Donegal Browne









Thursday, November 08, 2007

Battle of the Bath 3 or Mr. Junco gets a bath or else!


But first, one of the overwintering Blue Jays finally allowed me to get a lens on him. I hadn't realized that they had feathers over their cere.


And besides that they've got whiskers like some of the swallows. Look for the black hair-like feathers near the hinge of his beak. The Jay is finishing his molt and there is a view of closed pin feathers, and above them a feather just emerging that looks like a fern. (There does seem to be intelligence in that look, don't you think?)

Now to poor Mr. Junco who's stopped by for a wash. He's dipping his beak in preparation for going in.


Unfortunately Mrs. House Finch arrives. He looks at her pointedly.

She leans in for a drink and Mr. Junco scolds. He was there first after all.

Then they're both off like a shot as Blue Jay takes precedence with he bombs in calling loudly.

Mr Junco hurries back and jumps in.
But leaps out when the female Cardinal arrives. He stares pointedly at her as well.

Then Mrs. House Finch arrives yet again and both smaller birds stare at female Cardinal.

Those two are off and suddenly Mr. Junco looks up. Ah oh.



He's double teamed Mrs. House Finch is back again accompanied by a Goldfinch. They converged from two sides.

Then Mr. Junco's back and going for the moment that he has to himself.

He scopes out the area.


Then goes in head first, legs and wings flailing.


Guess who? It's Mrs. House Finch once again. Though she looks like she'd have been willing to share. She has a "why did he leave" look on her face.

Then I notice Chewie staring at me between blades of grass.


When I looked back at the bath, the Mrs. had gone and two male House Finch are having a staring contest. They have their little finch beaks raised belligerently at each other.

And there she is back again, displacing the boys.

Now Mr Junco is back giving her a piece of his mind.

Then he raises his little beak. But before too long...

The doves move in, but not for long....

Only the Crows and the Jays argue with the squirrels. Speaking of squirrels, One Eye Squirrel came for some sunflower seeds today. His territory must be a distance off as he's not an every day visitor. He was sitting on the top of the picnic table and another male squirrel gave him the aggressive jaw quivering vocalization. One Eye returned the sound and then leaned down and bit a chunk of wood off the edge of the picnic table, jaw still revving. Then another bite, a few steps, and another. After that display, they split the patio in half and kept to their own portions.

In the meantime, the doves have come back for their bath.

They go at it with vigor. I'd just put another batch of warm water in the bird bath not long before.

She notices me.

And then does the exposed wing pit portion of the bath, a move done by most species in the dove and pigeon families. I've always tried to figure out exactly what the advantage is. In the sun, I thought it might be warming the underside but they do it no matter the light. Here it is well on it's way to sunset.

Friend notices me and flees while Doorstep finishes her session.

She checks to make sure I'm still in the same place.

He's back to keep her company.

She takes off. He watched her go and slumped a little. As if he didn't know why she'd left. Well, things are different in and out of breeding season.

The family begins to gather for baths and the nightly meeting of the flock. I see two more on the ground

Then realize that there are three near the patio foraging as well. Wait, that's eight. They seem to have gained a new friend. Perhaps a possible mate for one of the kids come Spring. We'll see.
Donegal Browne