The Condor/24 (6)/Perching Pelicans

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Perching Pelicans. — Three times in the past three years I have seen individuals of the California Brown Pelican (Pelecanus californicus) perch on the wire stretched just above the top of the rail of our pier. This wire is about ⅛ inch in diameter and it is stretched fairly taut, being supported at intervals of about ten feet by upright spikes so that its height above the pier rail is about four inches.

At 7:52 a. m. on September 19, 1922, while working at the end of the pier I noticed a Brown Pelican alight on the rail about one hundred feet away. I quickly took a fairly comfortable position with the intention of observing the bird's actions as carefully as possible. I could see his feet distinctly and his toes seemed to curl around and grasp the wire in the same way as those of a perching bird. He was standing almost erect and teetering a good deal in an effort to find his balance. Several times the pelican tried to stoop to a sitting posture but with very unsettling results. Once while trying to preen his breast feathers he almost fell over backward and had to flap his wings vigorously to get balanced again. Finally he became satisfied with the erect posture and remained in it for probably ten minutes. In the erect posture for a time his balancing movements were so nearly imperceptible at one hundred feet distance that I would not have been able to detect them if I had not had the advantage of a series of cross wires on a gate within about thirty feet of the bird. By use of these wires I was able to estimate that at best there was rhythmic movement of the head up and down through a distance of at least a half inch, varied every few seconds by a longer swing of two to three inches.

Just before this relatively stable period he had lifted first one foot and then the other several times as though the wire hurt his feet. Indeed, this performance reminded me very much of a barefoot boy trying to stand on a hot pavement. At the end of the quiet period the pelican began side-stepping and walked on the wire a distance of about four feet at the end of which he turned around facing in the opposite direction. Ii making the turn he got a good deal unbalanced and saved himself from falling by stepping onto the wooden rail with one foot. He again assumed the erect position and remained thus for some little time until excited by the screeching of a flock of gulls which flew near him. At 8:15 he flew away after having perched on the small wire for twenty-three minutes.

When first alighting he had been facing the pier and away from the water. The half turn made after the side-stepping performance brought him into a position facing the water. Before beginning the side-stepping he had made several efforts to stoop, with very strong appearance of getting ready to fly. Every effort to stoop destroyed his balance and he could not get a good jump into the air for starting flight. I do not think it possible that he could have gotten enough jump to enable him to clear the opposite rail. Whatever the actual reason for the half turn it certainly put him into position (facing the water) to launch easily into flight.

I have mentioned a failure to keep balance while attempting to preen. There were two or three fairly successful attempts but they were confined to very small adjustments of breast feathers with very brief action. At various times in the perching period the head was rotated from side to side but this did not involve much shifting in weight and was not very disturbing to balance.

The three cases which I have seen indicate that pelicans do have perching ambitions and that they can make a very creditable showing in a difficult situation. Do such performances indicate vestigial or initiatory tendencies in behavior? — W. E. Allen, Scripps Institution for Biological Research of the University of California, La Jolla, September 20, 1922.