The Egret with the sway catches the prey . . . maybe

When I was last in Florida, I enjoyed a few marvelous moments of unexpected urban birding. As I was heading back at the end of the day, I spotted a Great Egret (Ardea alba) just outside of the hotel where I stayed.


This would make a fine advertisement for the hotel. 15 December 2009, at the corner of S. Hamden Dr. and S. Gulfview Blvd.



I was concerned about scaring him away, but then he started slinking hither rather than whither.


And then it became obvious that he was not at all concerned with me and my camera.


I had been spotting those little lizards all over Clearwater Beach. I considered trying to photograph them but gave up; they were too speedy. The Egret provided me with an opportunity for a secondary capture.


The Egret did not seem to mind passers-by (some of whom also photographed him) or the auto traffic of the busy S. Gulfview Blvd.


This is urban birding. The Egret makes a grand leap over the hedge. In the background, there is the gas station at the very conveniently located convenience store where Bayway Dr. meets S. Gulfview Blvd (and love those petrol prices).

The terrestrial hunting technique of the Egret involves slow and patient pacing along the foliage. Just prior to a bill stab motion, side-to-side oscillation of the neck and, to a lesser degree, the head occurs. This has been reported in the literature as neck swaying and head swaying.Willard, 1977 It has been suggested that the purpose of this swaying may be to perturb prey, as well as to adjust for the slight parallax, helping the Egret to visually localize the prey.

In this case, perturbation was achieved, but the meal was not.

And in this case, the perturbation was quite a clumsy success.

Compared to five other species of Herons and Egrets, the Great Egret was reported to have the lowest ratio of success to bill stab attempts at about 13% while other head and/or neck swayers demonstrated a success rate of at least 50%.Rodgers, 1983

The Egret strikes and misses.

Nevertheless, the performance of this Great Egret was great and excellent among his species. On my watch, his success rate was near 50%. The Egret shows us how it is done.

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~ by finchwench on Tuesday, 2 February 2010.

One Response to “The Egret with the sway catches the prey . . . maybe”

  1. Lovely set of pictures!

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