Readers’ wildlife photographs

May 13, 2014 • 4:35 am

Stephen Barnard just keeps them coming. First, a panoramic view of the Nature Conservancy’s Silver Creek Preserve in Idaho. Barnard lives near here and, I believe, takes many of his photographs in the area:

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A mated pair of American avocets (Recurvirostra americana) feeding:

Avocets, feeding

An osprey (Pandion haliaetus), described by the Cornell bird site as “unique among North American raptors for its diet of live fish and ability to dive into water to catch them.”

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Finally, another avocet, in flight:

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14 thoughts on “Readers’ wildlife photographs

  1. Have there been seen any avocets with the beak curved the other way?

    Would the biomechanics work with a curved in the opposite direction?
    I know nothing about the lifestyle of avocets (unless they’re known as fossils?), but from the pictures, they appear to skim food from the air-water interface. The sector length of the beak which intersects the air-water interface (with modifications from surface tension) is going to relate to the amount of food per skim. If you look at the geometry (I could try to do this with formal maths, but just sketching it should be sufficient), that requires a concave-upwards beak profile. As long as the bird’s head is above water level. (Corollary : straight bills for penetrating straight into material, but concave-down for beaks whose mode of action depends on the neck or hips pivoting.
    what does Wikipedia say?

    Avocets have long legs and long, thin, upcurved bills (giving their scientific name Recurvirostra) which they sweep from side to side when feeding in the brackish or saline wetlands they prefer.

    I honestly did not know that before searching just now ; it’s just another demonstration of the predictive power of science. Maybe not as “up there” as Darwin’s Butterfly, but I like it.
    Checking further, I come across examples such as

    This Long-billed Curlew, like other shorebirds, has a long narrow bill for probing in mud and sand for insects and worms.

    Which fits my prediction pretty well. And there are also flamingoes, which feed by sweeping their bills side to side at the water surface, but have a concave-down beak … because they feed with their heads upside down. Which actually fits my model.

    1. They feed in the silt, most likely on small crustaceans and insect nymphs, often plunging their heads underwater.

    2. I think you missed the point of my question. The beak is curved to the bird’s _right_ as well. I was asking if any were ever spotted with the beak curved to the _left_.

      1. I didn’t notice that.
        Stephen Barnard seems to know more about this sort of dinosaur, so I think that’s a question for him. They’re a bit under-fossilised for me, really.
        Mind you, that does raise a question for me … would I be able to distinguish between left-to-right versus right-to-left sweeps in a trace fossil? That is a very good question, which I am going to have to think about.

        1. I don’t believe their bills are turned to one side or the other. They’re merely turned upward.

  2. That bend in the river is obviously one of your favorite spots, and for good reason.

    Is that a dust devil in the distance almost in the middle of the frame? Or is it a vehicle (etc.) kicking up dirt…?

    b&

    1. That Justin, a farm hand, drilling (i.e., planting) alfalfa in one of my fields.

      By the way, I’m happy to report that I’m no longer selling barley to Coors and Budweiser. I don’t like Coors’s politics and I don’t like either beer. I’ve planted 20 acres of a new barley variety for craft beer.

  3. Nature Conservancy is doing good there in Idaho, apparently. I wish they had done so well up by my sister’s outside of Missoula in the Potomac Valley, where they got hold of a piece then traded it, allowing a logging company to come in and decimate an old mature forest and destroy hillsides where there were several very rare species of plants and leave giant slash piles warting up the hillsides.

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