Bronx River Education

It’s an egret, for sure, but what kind?

July 9, 2009

On Wednesday morning, Josue, Cici and I introduced a group of students involved in the creation of a school mural to the Bronx River Forest and the Bronx River. On our reconnaissance of the area just prior to the walk, we came across an egret foraging while standing on a pile of recently accumulated detritus. The newly expanded island in the stream caused eddies and small ponds that offered great hunting grounds for the egret. As we watched, the egret moved its long, muscular neck almost imperceptibly before jabbing it into the water and coming up with a slender fish about 3 inches long ( a tessellated darter?) Egrets and herons differ from storks and flamingos in that their necks are hunting tools. The powerful muscles allow them to thrust down into the water in search of prey. You can best note the difference when in flight as the birds with the stronger muscles coil their necks back while those that just use their necks to reach down and filter the water fly with their necks stretched out straight. We kept as quit as possible and left the egret to finish its fishing somewhat in private.

But what kind of an egret was it? A Snowy Egret? A Great White Egret? The answer is in the beak and the feet. While the Great White Egret is larger than the Snowy Egret, size sometimes depends on perspective. This is a Great White Egret due to the fact the beak is yellow and the legs and feet are black (not the best view of the feet here), while the Snow Egret has a black beak, black leg and yellow feet. They can also be distinguished by hunting style. The Great White is patient, waiting for prey to come into range while the Snowy will actively kick up the bottom in an effort to stir up game. Makes you wonder if there is some connection between the Snowy’s style and the natural selection that gives it its yellow feet.

DG

Entry Filed under: sighted. .