Archive for February, 2020

29
Feb 20

A tea-kettle Song

The elegant stance of a Carolina Wren makes it look like it owns the world and knows it. (G. Thomas Bancroft)

The elegant stance of a Carolina Wren makes it look like it owns the world and knows it. This bird is frequently encountered on Christmas Bird Counts in the Eastern United States. (G. Thomas Bancroft)

A loud booming song came rattling up the ravine. It sounded like “tea-kettle-tea-kettle-tea-kettle” then a pause and more “tea-kettle-tea-kettles.” I jumped from foot to foot, trying to stay warm as I scanned the deciduous hardwood forest. The temperature hung around freezing, and I hadn’t brought enough layers to Pennsylvania for doing this Christmas Bird Count. 

The melody jumped to the other side of the gully, but nothing seemed to have moved under the massive red oaks and hickories. The bird should be hopping through the leafless bushes, maybe clinging to the bark on one of those trees, or zipping along a branch, all places that it should be easily visible. I shuffled to my left twenty paces, trying to get the blood moving, and started a systematic search. I knew what the bird was, a Carolina Wren, but for some unknown reason, I desperately wanted to see it. They don’t live in Seattle where I do now.

The Carolina Wren moves up the log, probing amont the wood for possible morsels on this cold winter day. (G. Thomas Bancroft)

The Carolina Wren moves up the log, probing among the wood for possible morsels on this cold winter day. (G. Thomas Bancroft)

These guys are small and chunky with a reddish-brown back and cap. Their white eyebrow and dark eyeline give them a distinguished look, and that long barred tail radiates energy. They always seem to be at high speeds, tackling life with gusto. Maybe it was envy that made me want to find it.

This was one of the first birds I’d learned as a small child. My sisters still have the farm where I grew up, and our place was just a quarter-mile up the hill from this location. For several years, a pair tried to nest in a little shed. A small cardboard box sat on a high shelf just above the lawnmower. They built their little grass cup in there and laid their creamy-white eggs with rusty brown spots. I’d try to sneak in and pull out the lawnmower without disturbing them. I don’t know if they ever were successful there. Once, late in the summer, I used a step ladder to look into the box and found four cold eggs still nicely clumped in the perfectly woven nest. That shed is gone now.

These little birds remind me of the Bewick’s Wrens that live in my Seattle yard. Bewick’s occasionally visit my suet in winter, and when it is warm, one will sing from the tops of bushes in my front yard. These two species are in separate genera but closely related. When we had heavy snows on the farm, Carolina Wrens occasionally came to our feeders, but their primary food was insects and spiders even in winter. 

The relative abundance of Carolina Wrens calculated from eBird Data by scientists at Cornel Laboratory of Ornithology

The general warming of the Eastern United States over the last fifty years has allowed Carolina Wrens to move north and increase in numbers. Severe winters, especially ones with snow that lasts for several weeks, knockback populations substantially. Christmas Bird Count data for Pennsylvania shows a significant crash after a particularly harsh winter in the mid-1990s. This wren has bounced back, though.

Christmas Bird Count data for Pennsylvania shows that populations of Carolina Wrens were depressed following a hard winter in the mid-1990s.

Perhaps, it’s that ability to recover after a catastrophe that was making me want to find this bird. A decade ago, I moved to Seattle following my wife’s death and a job loss. It took a while to find the right conditions, to find friends, to ….. 

A Carolina Wren sings its te-kettle tea-kettle song to let everyone know it is here. (G. Thomas Bancroft)

A Carolina Wren sings its tea-kettle tea-kettle song to let everyone know it is here in Pennsylvania and that he owns this place. Their songs are loud and easily heard from a long distance. (G. Thomas Bancroft)

che-wortel, che-wortel, che-wortel” interrupted my thoughts. It came from farther down the valley and closer to the trail. The wren had moved, and I hurried along. There it sat, bouncing up and down on those two thin legs, looking left and right, no indication of being cold.

A pair lived in this ravine throughout those years following the population crash. Another couple lived through those times in the black walnut grove around my boyhood home. They tried to nest a few times on the back porch of that house where my sisters still live. These birds persevered through those hard times.

The wren flitted up through a bush and looked right at me. It seemed to say, “What are you thinking about? Get on with it!” It then darted left and dashed down over the hill. I stared for a while and then turned to continue my count. That ball of energy had somehow warmed me up.

The Carolina Wren leans to its left and stares right at me as if its asking me a question. (G. Thomas Bancroft)

The Carolina Wren leans to its left and stares right at me as if it’s asking me a question. (G. Thomas Bancroft)

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21
Feb 20

Red-collared Widowbird

The Red-collared Widowbird landed on an exposed branch after doing his fluttering display over the adjacent grasslands in Nairobi National Park. (Thomas Bancroft)

The Red-collared Widowbird landed on an exposed branch after doing his fluttering display over the adjacent grasslands in Nairobi National Park. (Thomas Bancroft)

A long black tube-like bird came fluttering across the grasses. It seemed to be flying barely, flopping through the air, like a balance beam gymnast having trouble. “Can we stop?” I shouted to our driver. The slender shape was not quite vertical to the ground. I was standing in the back of a Landcruiser with my head out the roof, and there was no way I could hold binoculars still enough to train them on this creature.

It appeared all black, skinny, and extremely long, but I could get no details in the gray light. Body size seemed like our North American Red-winged Blackbird, but the tail was three, maybe four times the length of a blackbird’s tail. Males of African widowbirds are supposed to have extremely long tails that they use to attract females. So long, that its length can inhibit their ability to fly or so it seems.

“Is this a widowbird?” I called to Robinson, our guide and driver in Nairobi National Park.

“Yes, Red-collared, a male,” he had his binoculars up and was watching it come closer and closer.

I held my breath, hoping it might land nearby. Evolutionary, widowbirds are fascinating. The eight recognized species are all polygynous. Males vigorously defend a territory from all others, and they do a flight display to entice a female into their space. This individual was performing right now.

The longer his tail, the more likely a male Red-collared Widowbird will mate with several females. A more intense red collar will indicate that he is dominate over other males. Nairobi National Park, Kenya. (Thomas Bancroft)

The longer his tail, the more likely a male Red-collared Widowbird will mate with several females. A more intense red collar will indicate that he is dominant over other males. Nairobi National Park, Kenya. (Thomas Bancroft)

Widowbirds occur in the savannas of Africa and like areas were the grasses and short brush intertwine. Similar habitat to the Impala and Hartebeest that I’d seen earlier that day.

If a female shows interest, a male Red-collared Widowbird will use a partially built nest as a prop when he courts her. If she likes the nest structure and his performance, she might stay, accept the nest, and mate with him. But he doesn’t help the female finish the nest, incubate the eggs, or feed the young. So, by pairing with the male, the female gets the use of his territory and his sperm, nothing else. 

Presumably, she can evaluate the territory when moving through it, and in some respects, this will reflect the quality of the male, too. Good males will usually hold the best patches. She needs a safe place for her nest, one that will tend to protect it from predators, and an excellent area to find food for her young. But how else can she judge the “genetic” quality of the male?

The two central tail feathers on this male Red-collared Widowbird were still growing. Perhaps, these shorter feathers would make him less desirable to females. They use tail length as a que of his status. Nairobi National Park, Kenya. (Thomas Bancroft)

The two central tail feathers on this male Red-collared Widowbird were still growing. Perhaps, these shorter feathers would make him less desirable to females. They use tail length as an indicator of his quality. Nairobi National Park, Kenya. (Thomas Bancroft)

Experiments done by ornithologists showed that she focuses on the length of his tail. Males with longer tails tend to mate with more females than those with shorter ones. This drives selection on males for even longer ones, and they now have a tail during the breeding season that it is so long that it appears to hinder their ability to fly. Presumably, being able to survive with such an extravagant tail indicates their superiority. But what do males key on when they compete among themselves?

The male widowbird flew onto a bare branch not far from our vehicle, and his long tail blew back and forth in the wind. A bright crimson collar surrounded a black face and bill. Even in the subdued light, it radiated an intensity of red that surprised me. Of any birds, these males have the highest levels of carotenoids in those feathers. The concentrations of lutein and zeaxanthin help give that intense red color.

Converting nutrients into this red pigment is a costly process, requiring extra energy and a specialized metabolic pathway. But it is this red collar that tells other males an individual’s status. Scientists have manipulated the size and intensity of these collars and found that males with smaller or less bright ones had a harder time securing a territory or holding one. The researchers concluded that the “redness” of the collar and, to a lesser extent, its size indicated the dominance status of a male.

I jerked my hand down; it had been rubbing my beard for the last few minutes. I’d just turned 68 the previous week and had been wearing hair on my face for only five months. This widowbird was making me wonder why I kept it.  Last summer, I had let it grow on a week-long camping trip and discovered that some hair follicles on my cheeks and chin had stopped making melanin. The beard was a mixture of gray and brown, different from the solid brown on my head. 

After the camping trip, I let it continue to thicken because I wanted to see the mosaic of grays and browns when the beard was fuller. I had three weeks before a trip back east to see my sisters and planned to have it cut by then. The weekend before my flight, I went hiking with my nephew, and he talked me out of shaving it. To my surprise, my sisters liked it. They said something like, “It gives you a distinguished look.”  Later a friend said she thought it gave me a “professorial bearing.”

The male widowbird shifted his stance in the bush, and his red collar seemed to shimmer in the mid-day light. Perhaps, he was a dominant male, possessing a high-quality collar that intimidated other males, and his long black tail might be irresistible to females. He then flicked that tail and flew out over the grassland, waving it back and forth as he fluttered a few feet above the vegetation.

“You ready,” Robinson asked as the car started to drift forward.

“Yes,” came out as I rubbed my facial hair, wondering its significance for a single man at my age.

The intensity of red in the collar of this widowbird is an indicator of his dominance among male Red-collared Widowbirds. Males with bright red collars tend to hold the best territories. Nairobi National Park, Kenya (Thomas Bancroft)

The intensity of red in the collar of this widowbird is an indicator of his dominance among male Red-collared Widowbirds. Males with bright red collars tend to hold the best territories. Nairobi National Park, Kenya (Thomas Bancroft)

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14
Feb 20

The Pied-billed Grebe – A Not So Mundane Bird

The bill on this Pied-billed Grebe still had the dark ring around it that is typical of the breeding season. This one was in a small pond in Magnuson Park and It was mid January. (G. Thomas Bancroft)

The bill on this Pied-billed Grebe still had the dark ring around it that is typical of the breeding season. This one was in a small pond in Magnuson Park and it was mid-January. (G. Thomas Bancroft)

A movement caught my eye on the chilly January day. The glimpse had come from under the leafless branches of some willows and cottonwoods where a small pond was tucked in a thicket. I froze but could see nothing until I slowly crouched down. There, floating on the water, was a football-sized mass of feathers, tan along the waterline and darker above. It had two black eyes that glared at me from a smallish head, probably wondering if I was friend or foe.  A tiny Pied-billed Grebe drifted less than 20 feet from me.

Typically, they slink away, so I decided to settle here and see what it would do. These grebes are permanent residents in the Puget Trough, but over much of the United States, they are migratory. People seldom see them flying because they travel at night and rarely fly to escape a disturbance. Usually, Pied-bills dive and swim away, often undetected. People on birding outings will often comment, “Oh, it’s just a grebe,” wanting I presume to see something more colorful, bigger, less mundane.

The distribution of Pied-billed Grebes in the Western Hemisphere as calculated from eBird Data by scientists at Cornel Laboratory of Ornithology.

Their distribution is fascinating with breeding populations in both North and South America. Although a few are in Hispaniola, Puerto Rico, and Central America, generally, a big geographic gap exists between those groups on each continent. 

The Pied-billed Grebe sat motionless in the water after surfacing from a dive. They are permanent residents in the Puget Sound area of Washington. (G. Thomas Bancroft)

The Pied-billed Grebe sat motionless in the water after surfacing from a dive. They are permanent residents in the Puget Sound area of Washington. (G. Thomas Bancroft)

For North America, the animation of weekly abundance data from eBird showed that in January, Pied-bills were concentrated in Florida and along the Southeast coastal plains and across into Texas and Northeastern Mexico. Lots were also in the central valley of California and then a few here in Puget Sound. Some were scattered elsewhere, especially Central Mexico and near the Gulf of California. By March, birds had moved into the Great Plains and by late April had extended into the Canadian prairies, Central Washington, and British Columbia. Their numbers in the Southeast had plummeted by April, but those in central California remained pretty constant. In the fall, they started to head back toward the Gulf Coast.

https://ebird.org/science/status-and-trends/pibgre/abundance-map-weekly?forceLogin=true

In South America, the migration was in the opposite direction. In late January, lots were in Northeastern Brazil and then scattered to northern Argentina. As the year progressed, they migrated south to breed from Southern Brazil into Central Argentina. A few were also in Chile, Equator, and Columbia. Of all the grebe species in the Western Hemisphere, Pied-bills have the most extensive distribution. 

The pied-billed Grebe slowly turned in the calm waters at Magnuson Park. It then just sank into the water and disappeared. (G. Thomas Bancroft)

The pied-billed Grebe slowly turned in the calm waters at Magnuson Park. It then just sank into the water and disappeared. (G. Thomas Bancroft)

The one in Magnuson Park, a protected area in Seattle, slowly turned a complete circle while keeping one eye on me. Its back and sides had water droplets beaded on the feathers. Those feathers seemed slicked down but waterproof. The bill still had the black ring mid-way out and the bluish-white base. Usually, they lose that band, and the bill becomes more yellowish-brown in the non-breeding season. Perhaps, its breeding hormones were still flowing here in January.

The bird radiated a sense of pride, confidence. In Celtic mythology, the grebe guards the spirit world and helps humans find beauty where they otherwise might not. The contours of its body, the S-shape of its neck, the tautness of its muscles all projected splendor. 

Suddenly, the grebe just sank out of sight, hardly making a ripple. No dive, it just dropped as if it was a rock gently placed on the surface. The bird must have compressed its body feathers, squeezing out the trapped air, and tightened its chest muscles to make its air sacks smaller, decreasing its buoyancy.  

I shook my head as I got back to my feet. Birds are so marvelous.

The Pied-billed Grebe glared at me from a small pond in Magnuson Park. Water droplets were beaded across its back and sides. (G. Thomas Bancroft)

The Pied-billed Grebe glared at me from a small pond in Magnuson Park. Water droplets were beaded across its back and sides. (G. Thomas Bancroft)

A version of this essay first appeared in the Washington Ornithological Newsletter #184.

http://wos.org/documents/wosnws/wosnews184.pdf#page=8

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7
Feb 20

Two Bachelors on the African Plains

An impala looks intently into the African Plains.

There, in the long green grass, stood two male impalas. Their curved horns rose several feet above their heads. With dark chestnut brown on their backs and a brownish white across their bellies, they blended into the savanna colors. Last night’s rain had slicked their fir down, but they showed no indication of being chilled. One raised its head, turning from nibbling on grass to stare right at me. I stood in the back of our vehicle with both hands gripping my binoculars, and my eyes studying every detail of these athletes. Here was the quintessential animal of the African plains, the one that everyone shows gracefully running while doing spectacular leaps. 

The Impala stared right at me, eyes intense, ears pointed forward.
The impala raised its head and stared right at me. He pricked forward both his ears and looked intently, finally deciding I was not a threat and went back to feeding.

His eyes seemed intense, the facial expression was inquisitive, and he’d pricked his two ears forward. The left one had two large tears partway out, well healed. Perhaps, a thorn snagged the ear as the antelope bounded through the scrub. His muzzle, though, really drew me. Its softness and roundness gave it a delicate mien. The lines of the nostrils came down to a split upper lip and then joined with the curved mouth. White fir-covered this area, contrasting with the chestnut of the body as if he had put on frosty lipstick that morning. 

Those glossy black horns, though, rose elegantly into the air. They came up from the head, going away from each other, then curving back and up more. Their length impressive, and black rings curled around each, giving them a carved look. The generic name for this species, Aepyceros, means “high-horned” and comes from ancient Greek. I switched to photographing him and began to wonder how someone could shoot such a beauty and mount his head on a wooden plate. But was that what I was doing with a camera, capturing my trophy? Possibly, I would print and attach a portrait of this guy on my wall. My shooting didn’t seem to affect him in the least.

An impala chews on grass.
The impala chewed the grass slowly, gradually pulling the long stems into its mouth. He twitched his ears back and forth, always attentive to what was around him. Africa is full of predators that like to eat this antelope.

He turned back to munching on grass, and the other one began to urinate right in front of us. These were two bachelor males, hanging out together. A male expends a lot of energy to maintain a harem of a couple of dozen females. He usually doesn’t have the experience or strength until he is three or four years old. Then he might successfully push out a harem owner and become the dominant one. He may only be able to keep that position for a short time before he, too, is supplanted. Maybe these were young males that hadn’t made that attempt. They looked fit, in prime condition. Perhaps they regularly practice fighting among themselves, preparing for their opportunity.

Two impalas graze on the African plains in Nairobi National Park.
Two impalas graze on the African plains in Nairobi National Park.

For about a decade, I’ve been a bachelor, too. After my wife died, I dated a few women, and at one point I’d thought I’d found someone to spend the rest of my days with. But the stress I was under then, caused by closing an organization down and laying off all the staff, put a rift into that hope. Impala males are under constant pressure when they are defending a group of females. They must run back and forth, keeping an eye on all their does and looking for rival males who might want to usurp their position or snitch a female away. It wears them out, burns up their energy reserves, exhausts them. But it gives them a chance for sex and therefore leaving progeny. Companionship doesn’t seem to be part of it.

These two males looked like buddies, spending their days together, helping each other detect predators, finding the right morsels to chew, and sharing their experiences and thoughts. For me, that seems to be what is essential now, as I’m about to complete my seventh decade on this planet. Someone to discuss these sightings, to hear what the other saw that I failed to notice, and to find joy in the other’s thoughts, reactions, would be nice. Life develops more dimensions when it can be seen through another set of eyes. 

The back of the impalas head.
The rain had slicked down the impala’s fir, giving it texture. He’d pricked his ears forward to see what might be approaching on the African Plains.

These two impalas started to mosey into the bush, picking at grass pieces, nipping on twigs. Maybe, they were headed to a secluded spot where they could bed down and chew their cuds, processing a second time that quick meal of the morning. Now, that is a good life!

The impala twists its head to look behind it.
On December 5th, I saw my first impala. This male was grazing on the edge of a thicket in Nairobi National Park. They are more elegant and graceful than I’d imagined.
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