A vocabulary of landscape — a landscape of words
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shearwater
A shearwater is a long-winged seabird that flies by banking in long arcs, tilting until a wingtip nearly touches the surface, using the wind gradient just above the waves to travel enormous distances at almost no muscular cost. It comes to land only to breed, in burrows on islands at night, and it is helpless ashore. Several species make transequatorial migrations of tens of thousands of miles a year.
Etymology
The English name is for the flight: the bird appears to shear or cut the water with a wingtip. The technique is called dynamic soaring and it exploits the fact that wind moves more slowly right at the surface than a few feet above it, so a bird crossing repeatedly between the two layers extracts energy from the difference.
Notes
The Manx shearwater is the record holder for demonstrated navigation. One taken from its burrow in Wales and released in Boston returned to the same burrow in twelve and a half days, having crossed the Atlantic. Individuals of the species have been recorded at over fifty years old, which means a single bird can cover a distance equivalent to several round trips to the moon.