Snowy Egrets: Foot-dragging and Aerial Feeding

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     Aerial feeding by Snowy Egrets has been observed by many people. Among the various forms that have been described are: hovering to retrieve surface food, agitating the water with one or both feet while hovering (hovering-stirring), capturing prey from the water while continuing in direct flight (dipping), and dragging one or both feet in the water while catching prey during direct flight (foot-dragging).

     Examples of foot-dragging behavior observed at the Bayou Sauvage NWR in Louisiana (2013) and Merritt Island NWR in Florida (2015) are shown below - foot-dragging (photos 1-4), striking behavior during foot-dragging (photos 5-8), and successful capture of minnows (photos 9-12).

Click on the images to see a larger view.

Snowy Egret Foot-dragging, Bayou Sauvage NWR (LA), 2013

D300S, 300mm f/4 + 1.7x tc, handheld
1/3200 sec at f/7.1, ISO 500

Snowy Egret Foot-dragging, Bayou Sauvage NWR (LA), 2013

Snowy Egret Foot-dragging, Merritt Island NWR (TX), 2015

D4, 500mm f/4, handheld
1/2500 sec at f/10, ISO 1100

Snowy Egret Foot-dragging, Merritt Island NWR (TX), 2015

Snowy Egret Foot-dragging, Merritt Island NWR (TX), 2015

D4, 500mm f/4, handheld
1/2500 sec at f/10, ISO 900

Snowy Egret Foot-dragging, Merritt Island NWR (TX), 2015

Snowy Egret Foot-dragging, Merritt Island NWR (TX), 2015

D4, 500mm f/4, handheld
1/2500 sec at f/10, ISO 900

Snowy Egret Foot-dragging, Merritt Island NWR (TX), 2015

The foot-dragging Snowy Egret is in the left edge of the pool of water, below and to the left of the Roseate Spoonbill.

Snowy Egret, Striking while Foot-dragging, Bayou Sauvage NWR (LA), 2013

D7100, 300mm f/4 + 1.7x tc, handheld
1/5000 sec at f/8, ISO 640

Snowy Egret, Striking while Foot-dragging, Bayou Sauvage NWR (LA), 2013

Snowy Egret, Striking while Foot-dragging, Merritt Island NWR (TX), 2015

D4, 500mm f/4, handheld
1/2500 sec at f/10, ISO 1250

Snowy Egret, Striking while Foot-dragging, Merritt Island NWR (TX), 2015

Snowy Egret, Striking while Foot-dragging, Merritt Island NWR (TX), 2015

D4, 500mm f/4, handheld
1/2500 sec at f/10, ISO 1000

Snowy Egret, Striking while Foot-dragging, Merritt Island NWR (TX), 2015

Snowy Egret, Striking while Foot-dragging, Bayou Sauvage NWR (LA), 2013

D7100, 300mm f/4 + 1.7x tc, handheld
1/5000 sec at f/8, ISO 640

Snowy Egret, Striking while Foot-dragging, Bayou Sauvage NWR (LA), 2013

Snowy Egret with minnow captured while foot-dragging, Merritt Island NWR (TX), 2015

D4, 500mm f/4, handheld
1/2500 sec at f/10, ISO 1100

Snowy Egret with minnow captured while foot-dragging, Merritt Island NWR (TX), 2015

Snowy Egret with minnow captured while foot-dragging, Merritt Island NWR (TX), 2015

D4, 500mm f/4, handheld
1/2500 sec at f/10, ISO 1000

Snowy Egret with minnow captured while foot-dragging, Merritt Island NWR (TX), 2015

Snowy Egret with minnow captured while foot-dragging, Merritt Island NWR (TX), 2015

D4, 500mm f/4, handheld
1/2500 sec at f/10, ISO 1250

Snowy Egret with minnow captured while foot-dragging, Merritt Island NWR (TX), 2015

Snowy Egret with minnow captured while foot-dragging, Merritt Island NWR (TX), 2015

D300S, 80-400mm f/4.5-5.6 + 1.4x tc, handheld
1/4000 sec at f/8, ISO 800

Snowy Egret with minnow captured while foot-dragging, Merritt Island NWR (TX), 2015

     The actual function of the foot-dragging is unclear, based upon the literature I have been able to access. Suggested functions include startling prey, slowing forward momentum, and steering or stabilization effects. One of the interesting ideas about why the birds engage in this energy consuming behavior is that, in areas where numerous alligators are present, it may be less hazardous than feeding while wading or perched near the water (Davis and Jackson, 2000).

References

Kushlan, J. A. 1972. Aerial feeding in the Snowy Egret. Wilson Bulletin 84:199-200.

Kushlan, J. A. 1976. Feeding behavior of North American Herons. Auk 93:86-94.

Davis, W.E. and Jackson, J.A. 2000. Aerial foraging by Tricolored Herons, Snowy, and Great Egrets. Florida Field Naturalist 28(4):192-194.

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David Sparks

I retired in 2005 after 40 years of research and teaching at the University of Alabama in Birmingham (24 years), the University of Pennsylvania (8 years) and the Baylor College of Medicine (8 years). Photography is my retirement hobby.

Nature photography, especially bird photography, combines a number of things that I really enjoy: bird-watching, being outdoors, photography, travel, messing about with computers, and learning new skills and concepts.  I now spend much of my time engaged in these activities.

David Sibley in the preface to The Sibley Guide to Birds wrote "Birds are beautiful, in spectacular as well as subtle ways; their colors, shapes, actions, and sounds are among the most aesthetically pleasing in nature."  My goal is to acquire images that capture the beauty and uniqueness of selected species as well as images that highlight the engaging behaviors the birds exhibit.