Great egret, Crissy Field
Whether in the marsh or along the dunes, you're likely to come across some majestic and sizable waterfowl during a walk at Crissy Field. This great egret, one of the larger members of the heron family, was spotted alongside the marsh waters.
The great egret's signature costume is a yellow bill and long black legs, as opposed to its cousin, the snowy egret, which sports the opposite color combination. Great egrets, found on all continents except Antarctica, average about 40 inches in height with wingspans of up to 57 inches.
The snowy egret also populates Crissy Field marsh. You can distinguish it from its larger cousin, the great egret, by its black bill and yellow feet. The snowy egret is also considerably smaller, standing about 2 feet tall.
Brown pelicans, with wingspans of up to 8 feet, are frequent visitors to Crissy Field, and can often be seen skimming the open waters of the Golden Gate. In the 1970s, research on the negative effects of DDT on brown pelican eggs helped get the pesticide banned.
Occasionally, the pelicans will repeatedly slap their wings against the water, splashing around. It's not entirely clear what drives this behavior, but they may be scavenging for food near the surface of the water.