Yesterday afternoon, as northeast winds raked Sarasota Bay, I watched as several species of birds used the same fishing technique. Ospreys, belted kingfishers and royal terns all took advantage of the steady wind in their effort to snare prey.
After riding the wind southward, each would turn to face it head-on, hovering with the aid of its lifting force and working their way northward. If their dives were successful, they veered off to enjoy their meal in a sheltered location; when their attempts were aborted or futile, they would continue moving upwind until a fish was snared or until they chose to ride southward once again.
While most animal behavior (excluding that of humans and other intelligent species) is instinctual, the observed sail fishing is most likely learned through experience. Indeed, the birds also benefitted from the sun position (behind them while fishing) which clearly improved their ability to spot their prey. Had the wind been from the south, forcing them to look into the sun's glare and surface reflection, they would surely have not used it in this way. Then again, my limited observations hardly qualify as a scientific study.
