Great, Blue, Snowy, Heron, Egret — it can get confusing. Why is the blue one a heron and the white ones are egrets? What really is the difference? These are good questions. If you’re confused, you’re not alone. Here Wikipedia is very helpful.
To begin with, the Great Blue Heron, the Great Egret, and the Snowy Egret all belong to the Ardeidae family. That term comes from the Latin ardea and the ancient Greek erodios, both meaning “heron.” The first two are big birds having yellow or yellowish beaks. The Great Blue weighs from 4 to almost 8 lbs with a wingspan of of 66 to 79 inches. The Great Egret weighs from 1.5 to 3.3 lbs and has a wingspan of 52 to 67 inches. They belong to the Ardea genus of the Ardeidae family. The Great Blue Heron is Ardea herodias (heron-like heron), and the Great Egret is Ardea alba (white heron). That at least is the modern naming system. In the past, the Great Egret was often commonly called the great white heron, while scientists formerly assigned it to the Egretta genus, not the Ardea. These sliding and mixed-up labels illustrate the close kinship between these two big birds and the vagueness of the distinction. To make matters more complicated, there is a Great White Heron in Florida and the Caribbean, which may just be a color variation of the Great Blue Heron or may be a separate species — scientists aren’t sure.
Then there’s the Snowy Egret. The Snowy Egret has a black beak and is much smaller than the other two. It weighs less than a pound on the average and has a wingspan of about three feet. It still belongs to the Ardeidae (heron) family, but not to the Ardea (heron) genus. It gets put into the Egretta genus, carrying the name Egretta thula. Egretta comes from the French aigrette meaning little heron. Egrets are not a biologically distinct group from the herons; they carry a different label mainly due to size or color variations.
That’s the ABCs of the three members of the heron family that we see most commonly in and around Cesar Chavez Park. But there’s more here — there’s the Black-crowned Night Heron and the Green Heron — and there are dozens of other heron and egret species worldwide.