Ecolog: Here is an example of such behavior. I'll appreciate comments and references.
On August 15, the Santo Tomás came to a medium-sized island they called "La Asunción," after the Ascension of the Virgin Mary. Nubbled with sand and gravel, the island looked made of plaster. The patina, it turned out, came from the excrement of pelicans. Captain Peguero and Father Ascensión took a scouting party ashore. They found a pelican flapping one wing. The other was tied to its body. Although it couldn't move, piles of sardines lay around its webbed feet. Father Ascensión realized that "as he could not catch them by reason of his captivity," other pelicans had brought the fish, "so merciful are these birds." Ascensión also realized that the trapped bird was a native trick for fishing without getting wet. Once pelicans had brought enough, natives would leap from a bush, chase the birds away, and "obtain sufficient fish without great labor." Ascensión released the bird. Here's a link to the (secondary) source: http://www.sandiegoreader.com/news/2011/oct/26/unforgettable/ WT PS: My apologies to the individual with whom I corresponded several months ago on this subject; I can't find the correspondence in my files, and I don't remember his or her name.
