Regal Western-Bird
Hesperornis regalis
(Marsh, 1872)
    The Inland Sea of late Cretaceous North America is warm and fertile.  Fish, squid, and ammonites ply its waters, and these creatures are preyed upon by a variety of predators.  While the fish are prey to elasmosaurs and larger fish, and the ammonites are prey to mosasaurs, the principle predator of the squid is Hesperornis regalis.

    H. regalis and its kin, the hesperornithiforms, are extremely successful birds and they occupy most of the world's oceans.  Having lost the powers of flight long ago, these birds are completely aquatic. Their wings are almost nonexistent and their legs stick out from their bodies at right angles, creating a form that is extremely streamlined and efficient for swimming, but useless anywhere but in water.  Indeed, H. regalis and its kin are completely helpless on land, able  to move only by digging into the sand with their legs and pushing in the manner of sea turtles.  In the ocean, however, these birds are very fast, plowing rapidly through the water with sharp strokes from their legs.  The feet of H. regalis are very large and its toes possess flattened pads to provide greater push.

    Although H. regalis is quite fast, lacking wings, it has no efficient means of turning without slowing forward momentum ( Toby White ).  Each turn must be made with sidewars stroaks of its back legs and so H. regalis, more-or-less relegated to moving in strait lines if it wishes to move quickly.  It cannot effectively hunt fish because it lacks their cornering abilities, but squid, which also lack the means of turning while moving forward, are the perfect prey for H. regalis .  These large birds hunt in small flocks, diving into schools of squid and then flitting back and forth with quick bursts of speed.  Each burst is accompanied by a twist of the mobile neck and a snap of the tooth-lined beak.  Soon, the school of squid has dispersed and the H. regalis are fed.


Thanks to Toby White for his inspirational essay and his collaberation, and Ray Stanford, of course.

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© Daniel Bensen 2000
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