Tag Archives | birds

Floating Dinosaur Birds

American White Pelican

American White Pelican

What California bird weighs five pounds more than our ten-pound eagles, has a wingspan two feet longer than the eagles’ seven feet, and a beak twice as long as a great blue heron’s? What bird is rumored to eat its own young, and also to feed its young with its own blood? What bird is noted in a 1910 poem by Dixon Lanier Merritt as wonderful because “His bill will hold more than his belican”?

Yes, the bird is the American White Pelican. (And yes, the poem is by Dixon Merritt, not Ogden Nash.)

These old birds, with fossil relatives going back half way to the dinosaurs, are shy of people, and remain an infrequent sight in Shasta County. But they are here. They nest along the shallow lakes of north-eastern California, and they winter even closer, throughout the Sacramento River Delta. Occasionally we spot them.

American White Pelican Group In Flight

On a quiet summer day they might float high overhead. They typically proceed in a silent group of fifteen or so, with not a single one of them deigning to speak or flap a wing. Their long bills spear forward like a pteradactyl’s; their motionless, extended wings show black flight feathers on otherwise snowy plumage. They hang in the summer-blue sky, still as pallbearers, seeming beyond the rule of something as mundane as gravity.

But of course they are fellow Earthlings, and sometimes will tilt Earthward and glide severally into a water-ski landing on a shallow lake. They prefer shallow lakes because of their feeding style.

Brown Pelican Dive

Brown Pelican Dive

Their coastal cousins, the brown pelicans, plunge into the water and scoop a beak-full of ocean and, they hope, stunned fish. White pelicans, on the other hand, paddle along the surface to find their food. Frequently they group together to swim-herd fish into shallow coves, where they can more easily scoop a mouthful of prey, either from their normal floating position or by tipping tail-up like a mallard. White pelicans will swallow salamanders and crawdads, but they mostly dine on warm-water fish like carp and minnows.

Each spring, the adults’ beaks brighten from yellow to orange, and they develop a rounded ornamental fin on their upper bills—an accessory that perhaps one must be a pelican to admire. The mated pair scrapes out a hollow in sand or gravel where the female lays 2-3 eggs. Only one of the young will usually fledge. Their in-nest competition is fierce.

While incubating or otherwise resting, pelicans often tuck their bills down their front sides. It may be this habit and the red-orange bill of the breeding season that fostered the mistaken myth that adult pelicans feed the young their blood. They do not.

American White Pelican Resting

As for the grisly tale that parent pelicans eat their offspring: adult pelicans do not carry food to their young in their pouched beaks. They swallow the food and then regurgitate it for the nestling. On its part, the baby stimulates regurgitation by sticking its own beak down its parent’s throat. The scene looks very much like the parent is eating its baby, head first. The feeding practice and the tale it inspired are primitive and perhaps galling; but the unpretentious dining style seems to have worked for 30 million years.

White pelicans declined for the first half of last century, perhaps in part due to the loss of a major nesting rookery when the progenitors of the Westlands Water District drained Tulare Lake, which at the time was the largest lake surface west of the Mississippi. But now the pelicans are recuperating—into new trouble, expanding into the southeast where catfish farms create rich feeding grounds.

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A Thanksgiving Celebration                           of the part of the bird we don’t eat

Peregrine Falcon

Peregrine Falcon

Bill, neb, schnoz – whatever it’s called, a bird’s beak is its second most important appendage after its wings. Since birds’ upper limbs are devoted to flight, the beak is vitally important in manipulating objects for feeding and nest building. Although some species are able to use feet for those purposes, many rely entirely on their bills.

The upper and lower mandibles comprising the beak are bony structures covered with keratin, a substance similar to human fingernails – and also similarly, constantly growing. The keratin layer may be very rigid and powerful as in the woodpeckers, whose beaks can drill nest holes or tease out insects in hardwood trees. In some species such as puffins and White Pelicans, the keratin forms projections during breeding season, presumably to enhance their attractiveness to prospective mates. These ornaments are shed after nesting time.

Icthyornis dispar

Icthyornis dispar

So, how did the toothed jaws of ancestral dinosaurs become transformed into modern beaks? A strong hint is offered by the recently reconstructed fossils of an ancient sea bird, Icthyornis dispar, that lived alongside dinosaurs 87 to 82 million years ago. Although it had dinosaur-like teeth, its long, narrow jaw was tipped by a tiny beak that it could have used like tweezers to grasp objects. The scientist that led the effort to reconstruct this bird said that it pecked like a bird, but bit like a dinosaur.

Red-breasted Sapsucker

Red-breasted Sapsucker

Over the millennia since then, adaptation to many different foods and environments has led to the vast variety of bills seen in modern birds. Form follows function, and so we have finch and sparrow beaks that act as crackers for seed-opening; eagles with shredders to tear apart meat; woodpeckers with chisels to bore into wood for insects; hummingbird probes used to reach into flowers for nectar; heron and kingfisher spears for skewering fish or frogs; and the warblers’ tweezers for grabbing insects. Not all birds have beaks specialized for a single purpose – the omnivorous crow has a versatile beak that all by itself can be likened to a Swiss army knife.

American Crow

American Crow photo courtesy of Ingrid Taylar

Most birds have little or no sense of smell, but there are notable exceptions. Vultures find the carrion they eat by odor – a characteristic taken advantage of by oil pipeline companies. By including a decay molecule in the crude oil, oil companies attract a cloud of vultures to leaks. The vultures, in turn, are followed by pipeline tenders with repair equipment. At sea, the tables are turned. Some seabirds can follow an odor plume to locate dead fish – and in this case the birds take advantage of the humans to detect fishing boats and their discards.

Generally, nostrils are on the part of birds’ beaks close to the head. However, New Zealand’s distinctive kiwi has nostrils near the tip of the beak where its well-developed sense of smell helps it find the insects and earthworms that it eats in the leaf litter.

Kiwi

Kiwi

The flamingo feeds in a manner as distinctive as its tropical appearance. It partially submerges its beak in prey-rich water, holding it upside down so that the upper mandible is below the lower mandible. It draws in large amounts of water and sieves out small organisms by means of hair-like projections on its beak. Thus, it is a filter-feeder, a characteristic it shares with baleen whales and oysters!

American Flamingo

American Flamingo

Our familiar hummingbirds have tropical cousins with amazingly long or fantastically curved beaks that match the corolla tubes of the flowers they feed from. Scientists who study them think that they are partnered in an “arms race” against other flowers and birds. As the flower and the hummingbird team becomes increasingly matched to just each other, they become physiologically committed to just their unique flower-bird relationship, and they exclude other species from their activity. It is as if they are in a long process of being wedded to each other.

Anna's Hummingbird

Anna’s Hummingbird

You don’t have to travel to exotic places or visit zoos to see these amazing beaks in action. Notice the different ways the house finches and the nuthatches that visit your feeders get into the seeds that they eat. Look at the bills of the birds in your yard – do they look like tweezers, probes or chisels? Then watch and see how the bird uses its beak. This makes another way to enjoy the birds around us.

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Fall River Christmas Bird Count

Participants will meet at the Fall River Hotel in Fall River Mills for a family-style breakfast and assignments. From Redding, take Hwy. 299E for approximately 75 miles. After crossing the Fall River, take the second right and look for the hotel on the right. Every year, some birders spend the night at this quaint hotel (Phone: 530-336-5550) and avoid the early morning drive. Eastern Shasta County birders are especially invited to participate. After the count, compilation will be held at Round Table Pizza on Lake Blvd. behind MacDonald’s Restaurant in Redding. The room at Round Table Pizza is reserved for us from 5:30pm to 8:30pm. Please RSVP to Bob & Carol Yutzy (boby@c-zone.net) if you hope/plan to participate and let them know if you want breakfast at the hotel so we can give them an estimated number of folks for breakfast.

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Family/Beginner Bird Walk at Turtle Bay

We invite beginners of all ages to our introductory walks on the first Saturday of each month. The walks begin at 9am and meet in the parking lot near the Monolith structure at the South end of the Sheraton Hotel. Binoculars and field guides will be available to loan. Call Roberta Winchell, 530-945-8342, for more information.

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Mid-week Field Trip at Clover Creek

In previous Novembers, Clover Creek Preserve has had some real treats for birders (though not guaranteed), including White-tailed Kite, Cedar Waxwing and Say’s Phoebe. More likely are a variety of sparrows such as Fox Sparrow and Lark Sparrow. Several duck species will be there: Ruddy Duck, Ring-necked Duck, occasionally Green-winged Teal and others. The vernal pools (if filled) may attract Greater and Lesser Yellowlegs. Open space birds such as American Pipit, Western Bluebird and Western Meadowlark are usual. Join trip leader Linda Aldrich in the parking lot off Shasta View at Venus Street at 8:00 am for this half-day trip.

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