Ivorybill woodpecker

"The population of the largest woodpecker in North America, the crow-size ivorybill, was already small by March 1938, when guide J. J. Kuhn and ornithologist James Tanner banded this baby in a Louisiana swamp. After jumping from its nest, the little ivorybill "climbed up Kuhn's arm . . . until it reached his shoulder . . . and gave a few sharp taps on his cap. . . . Upward it climbed until it was perched on the cap," wrote Tanner, who returned it to its nest. Though Tanner sighted the same bird the next year, only a few more ivorybills were ever seen, anywhere. The last confirmed sighting was in 1971 in southern Louisiana..." (Image and text from National Geographic website)